WorldWideScience

Sample records for school speed zones

  1. Speeds in school zones.

    Science.gov (United States)

    2009-02-01

    School speed zones are frequently requested traffic controls for school areas, based on the common belief : that if the transportation agency would only install a reduced speed limit, then drivers would no longer : speed through the area. This resear...

  2. A Review of Vehicles Speed on School Safety Zone Areas in Pekanbaru City

    Science.gov (United States)

    Dwi Putri, Lusi; Soehardi, Fitridawati; Saleh, Alfian

    2017-12-01

    School Safety Zone is a location or region on particular roads that are time-based speed zone to set the speed of the vehicle in the school environment. The maximum speed limit permits entering a School Safety Zone, especially in Pekanbaru City is 25 km / h and an outline of the speed limit permit vehicles that pass through the School Safety Zone in Indonesia is generally 20-30 km / h. However, the vehicles speeds that pass School Safety Zone are higher than permit speeds.To ensure the level of vehicle offense across the territory of the School Safety Zone so it is necessary a primary data which is taken randomly based on field survey for 3 days at schools that has that facility ie SDN 3 Jalan Kesehatan Pekanbaru City, SDN 68 Jalan Balam Ujung Kota Pekanbaru and SDN 143 Jalan Taskurun Kota Pekanbaru. Furthermore, the data were taken in good condition that is at 6:30 to 7:30 am and at 12:00 to 13:00 pm. In addition, the data obtained is mileage and travel time of the vehicle. Both of these data can generate good speed value that passes through the area of School Safety Zone. Based on the research findings, the vehicle speed passing through the area of School Safety Zone is incompatible with speed permit at 35 km / h with a maximum average percentage of the rate of offense in the area of the school zone is 91.7%. This indicates that the vehicle passes School Safety Zone not following the rules of the maximum limit area and can be potentially harmful to elementary school students.

  3. Driver speed limit compliance in school zones : assessing the impact of sign saturation.

    Science.gov (United States)

    2013-10-01

    School zones are often viewed as an effective way to reduce driving speeds and thereby improve : safety near our nations schools. The effect of school zones on reducing driving speeds, however, is : minimal at best. Studies have shown that over 90...

  4. S3: School Zone Safety System Based on Wireless Sensor Network

    Science.gov (United States)

    Yoo, Seong-eun; Chong, Poh Kit; Kim, Daeyoung

    2009-01-01

    School zones are areas near schools that have lower speed limits and where illegally parked vehicles pose a threat to school children by obstructing them from the view of drivers. However, these laws are regularly flouted. Thus, we propose a novel wireless sensor network application called School zone Safety System (S3) to help regulate the speed limit and to prevent illegal parking in school zones. S3 detects illegally parked vehicles, and warns the driver and records the license plate number. To reduce the traveling speed of vehicles in a school zone, S3 measures the speed of vehicles and displays the speed to the driver via an LED display, and also captures the image of the speeding vehicle with a speed camera. We developed a state machine based vehicle detection algorithm for S3. From extensive experiments in our testbeds and data from a real school zone, it is shown that the system can detect all kinds of vehicles, and has an accuracy of over 95% for speed measurement. We modeled the battery life time of a sensor node and validated the model with a downscaled measurement; we estimate the battery life time to be over 2 years. We have deployed S3 in 15 school zones in 2007, and we have demonstrated the robustness of S3 by operating them for over 1 year. PMID:22454567

  5. Driver behavior and accident frequency in school zones: Assessing the impact of sign saturation.

    Science.gov (United States)

    Strawderman, Lesley; Rahman, Md Mahmudur; Huang, Yunchen; Nandi, Apurba

    2015-09-01

    Based on the models of human information processing, if a driver observes too many of the same signs, he or she may no longer pay attention to those signs. In the case of school zones, this expected effect may lead to non-compliance to posted speeds, negatively impacting safety around nearby schools. This study aims to investigate the effect of the number of nearby school zones on driver behavior (vehicle speed and compliance) and accident frequency. As a measure of the density of school zones, this study introduced and defined a new term sign saturation and presented a methodology to calculate sign saturation for school zones. Results found a significant effect of sign saturation on vehicle speed, compliance, and accident frequency. This study also examined the speeding behavior in school zones for different time of the day and day of the week. Results found that speeding was more prevalent in the early mornings and during the weekends. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Evaluation of Ohio work zone speed zones process.

    Science.gov (United States)

    2014-06-01

    This report describes the methodology and results of analyses performed to determine the effectiveness of Ohio Department of Transportation processes for establishing work zone speed zones. Researchers observed motorists speed choice upstream of a...

  7. Perils of using speed zone data to assess real-world compliance to speed limits.

    Science.gov (United States)

    Chevalier, Anna; Clarke, Elizabeth; Chevalier, Aran John; Brown, Julie; Coxon, Kristy; Ivers, Rebecca; Keay, Lisa

    2017-11-17

    Real-world driving studies, including those involving speeding alert devices and autonomous vehicles, can gauge an individual vehicle's speeding behavior by comparing measured speed with mapped speed zone data. However, there are complexities with developing and maintaining a database of mapped speed zones over a large geographic area that may lead to inaccuracies within the data set. When this approach is applied to large-scale real-world driving data or speeding alert device data to determine speeding behavior, these inaccuracies may result in invalid identification of speeding. We investigated speeding events based on service provider speed zone data. We compared service provider speed zone data (Speed Alert by Smart Car Technologies Pty Ltd., Ultimo, NSW, Australia) against a second set of speed zone data (Google Maps Application Programming Interface [API] mapped speed zones). We found a systematic error in the zones where speed limits of 50-60 km/h, typical of local roads, were allocated to high-speed motorways, which produced false speed limits in the speed zone database. The result was detection of false-positive high-range speeding. Through comparison of the service provider speed zone data against a second set of speed zone data, we were able to identify and eliminate data most affected by this systematic error, thereby establishing a data set of speeding events with a high level of sensitivity (a true positive rate of 92% or 6,412/6,960). Mapped speed zones can be a source of error in real-world driving when examining vehicle speed. We explored the types of inaccuracies found within speed zone data and recommend that a second set of speed zone data be utilized when investigating speeding behavior or developing mapped speed zone data to minimize inaccuracy in estimates of speeding.

  8. Evaluation of variable advisory speed limits in work zones.

    Science.gov (United States)

    2013-08-01

    Variable advisory speed limit (VASL) systems could be effective at both urban and rural work zones, at both uncongested and congested sites. At uncongested urban work zones, the average speeds with VASL were lower than without VASL. But the standard ...

  9. Drug-Free School Zones: Taking Charge.

    Science.gov (United States)

    Thomas, Carol F.

    Information for planning and implementing drug-free school zones within a broader school-community prevention and intervention program is provided in this guidebook. The first section provides background information on drug-free school zone legislation and common elements of drug-free school zones. The risk and protective factors for alcohol and…

  10. Evaluation of electronic speed limit signs on US 30.

    Science.gov (United States)

    2011-09-01

    This study documents the speed : reduction impacts of two dynamic, : electronic school zone speed limit signs : at United Community Schools between : Ames and Boone, Iowa. The school : facility is situated along US Highway 30, : a rural four-lane div...

  11. Soil Heavy Metal Concentration Patterns at Two Speed Zones along ...

    African Journals Online (AJOL)

    Soil Heavy Metal Concentration Patterns at Two Speed Zones along the Gaborone- Tlokweng Border Post Highway, Southeast Botswana. ... Since 1988 Botswana has been experiencing an unprecedented increase in vehicular traffic which is suspected to be having contamination effects on soils along heavily used roads ...

  12. Effect of In-Vehicle Audio Warning System on Driver’s Speed Control Performance in Transition Zones from Rural Areas to Urban Areas

    Directory of Open Access Journals (Sweden)

    Xuedong Yan

    2016-06-01

    Full Text Available Speeding is a major contributing factor to traffic crashes and frequently happens in areas where there is a mutation in speed limits, such as the transition zones that connect urban areas from rural areas. The purpose of this study is to investigate the effects of an in-vehicle audio warning system and lit speed limit sign on preventing drivers’ speeding behavior in transition zones. A high-fidelity driving simulator was used to establish a roadway network with the transition zone. A total of 41 participants were recruited for this experiment, and the driving speed performance data were collected from the simulator. The experimental results display that the implementation of the audio warning system could significantly reduce drivers’ operating speed before they entered the urban area, while the lit speed limit sign had a minimal effect on improving the drivers’ speed control performance. Without consideration of different types of speed limit signs, it is found that male drivers generally had a higher operating speed both upstream and in the transition zones and have a larger maximum deceleration for speed reduction than female drivers. Moreover, the drivers who had medium-level driving experience had the higher operating speed and were more likely to have speeding behaviors in the transition zones than those who had low-level and high-level driving experience in the transition zones.

  13. Cutting zone area and chip morphology in high-speed cutting of titanium alloy Ti-6Al-4V

    International Nuclear Information System (INIS)

    Ke, Qing Chan; Xu, Daochun; Xiong, Dan Ping

    2017-01-01

    The titanium alloy Ti-6Al-4V has superior properties but poor machinability, yet is widely used in aerospace and biomedical industries. Chip formation and cutting zone area are important factors that have received limited attention. Thus, we propose a high-speed orthogonal cutting model for serrated chip formation. The high speed orthogonal cutting of Ti-6Al-4V was studied with a cutting speed of 10-160 m/min and a feed of 0.07-0.11 mm/r. Using theoretical models and experimental results, parameters such as chip shape, serration level, slip angle, and shear slip distance were investigated. Cutting zone boundaries (tool-chip contact length, length of shear plane, and critical slip plane) and cutting zone area were obtained. The results showed that discontinuous, long-curling, and continuous chips were formed at low, medium, and high speeds, respectively. Serration level, shear slip distance, and slip angle rose with increasing cutting speed. The length of shear plane, tool-chip contact, and critical slip plane varied subtly with increased cutting speed, and rose noticeably with increased feed. Cutting zone area grew weakly with increased cutting speed, levelling off at high cutting speed; however, it rose noticeably with increased feed. This study furthers our understanding of the shear slip phenomenon and the mechanism of serrated chip formation

  14. Cutting zone area and chip morphology in high-speed cutting of titanium alloy Ti-6Al-4V

    Energy Technology Data Exchange (ETDEWEB)

    Ke, Qing Chan; Xu, Daochun; Xiong, Dan Ping [School of Technology, Beijing Forestry University, Beijing (China)

    2017-01-15

    The titanium alloy Ti-6Al-4V has superior properties but poor machinability, yet is widely used in aerospace and biomedical industries. Chip formation and cutting zone area are important factors that have received limited attention. Thus, we propose a high-speed orthogonal cutting model for serrated chip formation. The high speed orthogonal cutting of Ti-6Al-4V was studied with a cutting speed of 10-160 m/min and a feed of 0.07-0.11 mm/r. Using theoretical models and experimental results, parameters such as chip shape, serration level, slip angle, and shear slip distance were investigated. Cutting zone boundaries (tool-chip contact length, length of shear plane, and critical slip plane) and cutting zone area were obtained. The results showed that discontinuous, long-curling, and continuous chips were formed at low, medium, and high speeds, respectively. Serration level, shear slip distance, and slip angle rose with increasing cutting speed. The length of shear plane, tool-chip contact, and critical slip plane varied subtly with increased cutting speed, and rose noticeably with increased feed. Cutting zone area grew weakly with increased cutting speed, levelling off at high cutting speed; however, it rose noticeably with increased feed. This study furthers our understanding of the shear slip phenomenon and the mechanism of serrated chip formation.

  15. Effects of tool speeds and corresponding torque/energy on stir zone formation during friction stir welding/processing

    International Nuclear Information System (INIS)

    Cui, S; Chen, Z W

    2009-01-01

    The way processing parameters and the measurable thermomechanical responses relate to the individual and combined flows forming the different processed zones during friction stir welding/processing has been studied. Experimentally, a cast Al-7Si-0.3Mg alloy was used to provide readily identifiable processed zones. A series of friction stir experiments covering a wide range of tool forward and rotation speeds were conducted followed by the measurement of individual and combined stir areas. It has been found that the basic modes of material flow did not change but the relative volume of each flow depended on both forward and rotation speeds. The trends observed in the present data explain how pin rotation relates to the material transportation mechanism and the associated torque required. This data also explains how forward speed, not rotation speed, relates to specific energy and the volume of the total stir zone.

  16. Predicting self-pollution inside school buses using a CFD and multi-zone coupled model

    Science.gov (United States)

    Li, Fei; Lee, Eon S.; Liu, Junjie; Zhu, Yifang

    2015-04-01

    The in-cabin environment of a school bus is important for children's health. The pollutants from a bus's own exhaust contribute to children's overall exposure to air pollutants inside the school bus cabin. In this study, we adapted a coupled model originally developed for indoor environment to determine the relative contribution of the bus own exhaust to the in-cabin pollutant concentrations. The coupled model uses CFD (computational fluent dynamics) model to simulate outside concentration and CONTAM (a multi-zone model) for inside the school bus. The model was validated with experimental data in the literature. Using the validated model, we analyzed the effects of vehicle speed and tailpipe location on self-pollution inside the bus cabin. We confirmed that the pollution released from the tailpipe can penetrate into the bus cabin through gaps in the back emergency door. We found the pollution concentration inside school buses was the highest when buses were driven at a medium speed. In addition, locating the tailpipe on the side, behind the rear axle resulted in less self-pollution since there is less time for the suction effect to take place. The developed theoretical framework can be generalized to study other types of buses. These findings can be used in developing policy recommendations for reducing human exposure to air pollution inside buses.

  17. Examining the impact of ASE (automated speed enforcement) in work zones on driver attention : final report.

    Science.gov (United States)

    2016-01-01

    Each year, there are over 500 fatal crashes in work zones in the U.S., with over 100 road construction workers : killed on work sites (NSC, 2011; FARS, 2011). Speed and distraction are among the top contributing factors to : work zone crashes (Garber...

  18. Reduction Vehicle Speed Using GPS Android Smart Phone Programming

    Directory of Open Access Journals (Sweden)

    Sameer Sami Hassan

    2017-07-01

    Full Text Available Today the new generation of smart phone such as Samsung galaxy, Sony, Motorola, HTC is used to build smart applications that made the human life more comfortable and safe. The Android open source operating system with java programming language can be used to develop such applications. In this paper a new software application has been developed using Samsung, galaxy note smart phone to control the speed of vehicle using GPS and Android programming for such smart phone. By collecting the speed and location information from Global Position System (GPS receiver and using the global map application programming interface to determine the location nearby university, school and hospital in Baghdad city. The application will be check the speed of vehicle in zone of school, hospital and university using GPS information. If the speed over the limit the application produce sound alarm to reduce the speed to set up limit.

  19. Effects of automated speed enforcement in Montgomery County, Maryland, on vehicle speeds, public opinion, and crashes.

    Science.gov (United States)

    Hu, Wen; McCartt, Anne T

    2016-09-01

    In May 2007, Montgomery County, Maryland, implemented an automated speed enforcement program, with cameras allowed on residential streets with speed limits of 35 mph or lower and in school zones. In 2009, the state speed camera law increased the enforcement threshold from 11 to 12 mph over the speed limit and restricted school zone enforcement hours. In 2012, the county began using a corridor approach, in which cameras were periodically moved along the length of a roadway segment. The long-term effects of the speed camera program on travel speeds, public attitudes, and crashes were evaluated. Changes in travel speeds at camera sites from 6 months before the program began to 7½ years after were compared with changes in speeds at control sites in the nearby Virginia counties of Fairfax and Arlington. A telephone survey of Montgomery County drivers was conducted in Fall 2014 to examine attitudes and experiences related to automated speed enforcement. Using data on crashes during 2004-2013, logistic regression models examined the program's effects on the likelihood that a crash involved an incapacitating or fatal injury on camera-eligible roads and on potential spillover roads in Montgomery County, using crashes in Fairfax County on similar roads as controls. About 7½ years after the program began, speed cameras were associated with a 10% reduction in mean speeds and a 62% reduction in the likelihood that a vehicle was traveling more than 10 mph above the speed limit at camera sites. When interviewed in Fall 2014, 95% of drivers were aware of the camera program, 62% favored it, and most had received a camera ticket or knew someone else who had. The overall effect of the camera program in its modified form, including both the law change and the corridor approach, was a 39% reduction in the likelihood that a crash resulted in an incapacitating or fatal injury. Speed cameras alone were associated with a 19% reduction in the likelihood that a crash resulted in an

  20. Coordinated Speed Oscillations in Schooling Killifish Enrich Social Communication

    Science.gov (United States)

    Swain, Daniel T.; Couzin, Iain D.; Leonard, Naomi Ehrich

    2015-10-01

    We examine the spatial dynamics of individuals in small schools of banded killifish ( Fundulus diaphanus) that exhibit rhythmic, oscillating speed, typically with sustained, coordinated, out-of-phase speed oscillations as they move around a shallow water tank. We show that the relative motion among the fish yields a periodically time-varying network of social interactions that enriches visually driven social communication. The oscillations lead to the regular making and breaking of occlusions, which we term "switching." We show that the rate of convergence to consensus (biologically, the capacity for individuals in groups to achieve effective coordinated motion) governed by the switching outperforms static alternatives, and performs as well as the less practical case of every fish sensing every other fish. We show further that the oscillations in speed yield oscillations in relative bearing between fish over a range that includes the angles previously predicted to be optimal for a fish to detect changes in heading and speed of its neighbors. To investigate systematically, we derive and analyze a dynamic model of interacting agents that move with oscillatory speed. We show that coordinated circular motion of the school leads to systematic cycling of spatial ordering of agents and possibilities for enriched spatial density of measurements of the external environment. Our results highlight the potential benefits of dynamic communication topologies in collective animal behavior, and suggest new, useful control laws for the distributed coordination of mobile robotic networks.

  1. Raising the speed limit from 75 to 80mph on Utah rural interstates: Effects on vehicle speeds and speed variance.

    Science.gov (United States)

    Hu, Wen

    2017-06-01

    In November 2010 and October 2013, Utah increased speed limits on sections of rural interstates from 75 to 80mph. Effects on vehicle speeds and speed variance were examined. Speeds were measured in May 2010 and May 2014 within the new 80mph zones, and at a nearby spillover site and at more distant control sites where speed limits remained 75mph. Log-linear regression models estimated percentage changes in speed variance and mean speeds for passenger vehicles and large trucks associated with the speed limit increase. Logistic regression models estimated effects on the probability of passenger vehicles exceeding 80, 85, or 90mph and large trucks exceeding 80mph. Within the 80mph zones and at the spillover location in 2014, mean passenger vehicle speeds were significantly higher (4.1% and 3.5%, respectively), as were the probabilities that passenger vehicles exceeded 80mph (122.3% and 88.5%, respectively), than would have been expected without the speed limit increase. Probabilities that passenger vehicles exceeded 85 and 90mph were non-significantly higher than expected within the 80mph zones. For large trucks, the mean speed and probability of exceeding 80mph were higher than expected within the 80mph zones. Only the increase in mean speed was significant. Raising the speed limit was associated with non-significant increases in speed variance. The study adds to the wealth of evidence that increasing speed limits leads to higher travel speeds and an increased probability of exceeding the new speed limit. Results moreover contradict the claim that increasing speed limits reduces speed variance. Although the estimated increases in mean vehicle speeds may appear modest, prior research suggests such increases would be associated with substantial increases in fatal or injury crashes. This should be considered by lawmakers considering increasing speed limits. Copyright © 2017 Elsevier Ltd and National Safety Council. All rights reserved.

  2. Exploring stop-go decision zones at rural high-speed intersections with flashing green signal and insufficient yellow time in China.

    Science.gov (United States)

    Tang, Keshuang; Xu, Yanqing; Wang, Fen; Oguchi, Takashi

    2016-10-01

    The objective of this study is to empirically analyze and model the stop-go decision behavior of drivers at rural high-speed intersections in China, where a flashing green signal of 3s followed by a yellow signal of 3s is commonly applied to end a green phase. 1, 186 high-resolution vehicle trajectories were collected at four typical high-speed intersection approaches in Shanghai and used for the identification of actual stop-go decision zones and the modeling of stop-go decision behavior. Results indicate that the presence of flashing green significantly changed the theoretical decision zones based on the conventional Dilemma Zone theory. The actual stop-go decision zones at the study intersections were thus formulated and identified based on the empirical data. Binary Logistic model and Fuzzy Logic model were then developed to further explore the impacts of flashing green on the stop-go behavior of drivers. It was found that the Fuzzy Logic model could produce comparably good estimation results as compared to the traditional Binary Logistic models. The findings of this study could contribute the development of effective dilemma zone protection strategies, the improvement of stop-go decision model embedded in the microscopic traffic simulation software and the proper design of signal change and clearance intervals at high-speed intersections in China. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Wind speed change regionalization in China (1961–2012

    Directory of Open Access Journals (Sweden)

    Pei-Jun Shi

    2015-06-01

    Full Text Available This research quantitatively recognized the wind speed change using wind speed trend and trend of wind speed variability from 1961 to 2012 and regionalized the wind speed change on a county-level basis. The mean wind speed observation data and linear fitting method were used. The findings suggested that level-I regionalization includes six zones according to wind speed trend value in different regions, viz. Northeast China–North China substantial declining zone, East–Central China declining zone, Southeast China slightly declining zone, Southwest China very slightly declining zone, Northwest China declining zone, and Qinghai–Tibetan Plateau slightly declining zone. Level-II regionalization divides China into twelve regions based on trend of wind speed variability and the level-I regionalization results.

  4. "AfterZone:" Outcomes for Youth Participating in Providence's Citywide After-School System. Executive Summary

    Science.gov (United States)

    Kauh, Tina J.

    2011-01-01

    This executive summary highlights the main findings from our participation and outcomes analysis of the "AfterZone" initiative--a citywide system-building effort in Providence, Rhode Island, that aims to provide high-quality, accessible out-of-school-time services to middle school youth. The summary briefly defines the AfterZone's unique…

  5. Processing Speed and Intelligence as Predictors of School Achievement: Mediation or Unique Contribution?

    Science.gov (United States)

    Dodonova, Yulia A.; Dodonov, Yury S.

    2012-01-01

    The relationships between processing speed, intelligence, and school achievement were analyzed on a sample of 184 Russian 16-year-old students. Two speeded tasks required the discrimination of simple geometrical shapes and the recognition of the presented meaningless figures. Raven's Advanced Progressive Matrices and the verbal subtests of…

  6. Conflict Management and Resolution Strategies between Teachers and School Leaders in Primary Schools of Wolaita Zone, Ethiopia

    Science.gov (United States)

    Shanka, Engdawork Birhanu; Thuo, Mary

    2017-01-01

    The purpose of this study was to investigate various strategies used to manage and resolve conflict between teachers and school leaders in government primary schools of Wolaita zone. The study employed a descriptive survey design where both quantitative and qualitative approaches were used to correct and analyze data, concurrently. From six…

  7. Variable Speed Limit (VSL) - Best Management Practice [Summary

    Science.gov (United States)

    2012-01-01

    In variable speed limit (VSL) zones, the speed : limit changes in response to traffic congestion, : adverse weather, or road conditions. VSL zones are : often highly automated and have been employed : successfully in several U.S. and European : locat...

  8. Harlem Children's Zone (HCZ) Promise Academy Charter Schools. What Works Clearinghouse Intervention Report

    Science.gov (United States)

    What Works Clearinghouse, 2018

    2018-01-01

    This intervention report presents findings from a systematic review of the "Harlem Children's Zone (HCZ) Promise Academy Charter Schools" conducted using the What Works Clearinghouse (WWC) Procedures and Standards Handbook (version 3.0) and the Charter Schools review protocol (version 3.0). No studies of the "HCZ Promise Academy…

  9. Global shear speed structure of the upper mantle and transition zone

    Science.gov (United States)

    Schaeffer, A. J.; Lebedev, S.

    2013-07-01

    resolution of the imaging. Our new shear speed model is parametrized on a triangular grid with a ˜280 km spacing. In well-sampled continental domains, lateral resolution approaches or exceeds that of regional-scale studies. The close match of known surface expressions of deep structure with the distribution of anomalies in the model provides a useful benchmark. In oceanic regions, spreading ridges are very well resolved, with narrow anomalies in the shallow mantle closely confined near the ridge axis, and those deeper, down to 100-120 km, showing variability in their width and location with respect to the ridge. Major subduction zones worldwide are well captured, extending from shallow depths down to the transition zone. The large size of our waveform fit data set also provides a strong statistical foundation to re-examine the validity field of the JWKB approximation and surface wave ray theory. Our analysis shows that the approximations are likely to be valid within certain time-frequency portions of most seismograms with high signal-to-noise ratios, and these portions can be identified using a set of consistent criteria that we apply in the course of waveform fitting.

  10. Design And Implementation Of Pc Based Over Speed Violation Management For Vehicles On Highway

    Directory of Open Access Journals (Sweden)

    Ni Ni Hlaing

    2015-07-01

    Full Text Available Abstract In the present day scenario traffic rules are frequently violated by the drivers and over speeding occur due to bad driving behavior. So a driver assistance system is provided to prevent over speeding violation of road rules also to display alert messages and gives alerts like road works steep slope school zone in the form of acoustical messages and also in LCD. The proposed system has a reporting displaying and database systemfor over speed violation management. This designed system has the ability to detect the speed of the vehicle in the roads and the main highways and the places where the drivers can use of more speed while driving. The laser transmitter senses the load entered by the vehicle and then the receiver unit sends to the microcontroller. The receiver unit is used by Light Dependent Resistor LDR. If the speed of vehicle exceeds the permissible speed for the highway this information will sent to PC which starts the camera to capture the vehicle. And all the information of vehicle are sent to database system. Then also shows the speed information on LCD.

  11. Food Insecurity and Its Association With School Absenteeism Among Rural School Adolescents in Jimma Zone, Ethiopia.

    Science.gov (United States)

    Tamiru, Dessalegn; Melaku, Yabsira; Belachew, Tefera

    2017-03-01

    Studies showed that poor health and nutrition among school adolescents are major barriers to educational access and achievements in low-income countries. This school-based study was aimed to assess the association of school absenteeism and food insecurity among rural school adolescents from grades 5 to 8 in Jimma zone, Ethiopia. Regression analyses were used to see the strength of association between dependent and independent variables using odds ratio and 95% confidence intervals. Multivariable logistic regression analysis was used to identify the predictor of school absenteeism. Validated tools are used to collect household food insecurity data. Results showed that school absenteeism is significantly high among adolescents from food insecure households when compared to adolescents from food secure households ( P absenteeism was negatively associated with male sex (adjusted odds ratio [AOR] = -0.91, 95% CI -1.85 to -0.03), household food security (adjusted odds ratio = -1.85, 95% CI -3.11 to -0.59), being an elder sibling (AOR = -0.37, 95% CI, -0.62 to -0.12), and mother involvement in decision making (AOR = -0.68, 95% CI, -1.33 to -0.03) while male-headed household was positively associated (AOR = 2.46, 95% CI, 1.37 to 4.56). Generally, this study showed that household food insecurity has significant contribution to school absenteeism among rural adolescents. Therefore, efforts should be made to improve household income earning capacity to reduce the prevalence of school absenteeism among rural school adolescents.

  12. Traffic safety program for school children through safe action and safe condition

    Science.gov (United States)

    Yulianto, Budi; Setiono, Mahmudah, Amirotul Musthofiah Hidayah; Santoso, Anjar Budi

    2017-06-01

    The facts indicate that the rights of pedestrians is on the wane. Many motorists are unwilling to provide a space for pedestrians, even when they want to cross the road at zebra-cross facility. The data of traffic accident in Surakarta City showed that 7.0% of accident victims in 2014 to 2015 were children aged 5-15 or the group of school-aged children. In general, the location of schools is on the edge of the road where a lot of vehicles run at high speed. Hence, it is very dangerous for the school children to cross the road. Pertaining to this issue, the Department of Transportation implements a program named School Safety Zone (ZoSS). ZoSS is a time-dependent speed control zone consisting of road markings, traffic signs, optional traffic signals, and rumble strips. The objective of this study was to evaluate the effectiveness of the ZoSS based on the perception of the users, including the students, teachers, parents, and community. This study was conducted through a series of activities including the distribution of questionnaire to obtain the road users' perceptions. The results showed that most of the respondents understood the meaning, aim, and benefit of ZoSS. However, it also found that traffic sign and method of cross the road (Four-T) was not recognized appropriately by the respondents. ZoSS program was generally ineffective since the pedestrians felt unsafe to cross the road due to the high-speed vehicles.

  13. 78 FR 19103 - Safety Zone; Spanish Navy School Ship San Sebastian El Cano Escort; Bahia de San Juan; San Juan, PR

    Science.gov (United States)

    2013-03-29

    ...-AA00 Safety Zone; Spanish Navy School Ship San Sebastian El Cano Escort; Bahia de San Juan; San Juan... temporary moving safety zone on the waters of Bahia de San Juan during the transit of the Spanish Navy... Channel entrance, and to protect the high ranking officials on board the Spanish Navy School Ship San...

  14. Energy Implications of Retrofitting Retail Sector Rooftop Units with Stepped-Speed and Variable-Speed Functionality

    Energy Technology Data Exchange (ETDEWEB)

    Studer, D.; Romero, R.; Herrmann, L.; Benne, K.

    2012-04-01

    Commercial retailers understand that retrofitting constant-speed RTU fan motors with stepped- or variable-speed alternatives could save significant energy in most U.S. climate zones. However, they lack supporting data, both real-world and simulation based, on the cost effectiveness and climate zone-specific energy savings associated with this measure. Thus, building managers and engineers have been unable to present a compelling business case for fan motor upgrades to upper management. This study uses whole-building energy simulation to estimate the energy impact of this type of measure so retailers can determine its economic feasibility.

  15. Speed of Language Comprehension at 18 Months Old Predicts School-Relevant Outcomes at 54 Months Old in Children Born Preterm.

    Science.gov (United States)

    Marchman, Virginia A; Loi, Elizabeth C; Adams, Katherine A; Ashland, Melanie; Fernald, Anne; Feldman, Heidi M

    2018-04-01

    Identifying which preterm (PT) children are at increased risk of language and learning differences increases opportunities for participation in interventions that improve outcomes. Speed in spoken language comprehension at early stages of language development requires information processing skills that may form the foundation for later language and school-relevant skills. In children born full-term, speed of comprehending words in an eye-tracking task at 2 years old predicted language and nonverbal cognition at 8 years old. Here, we explore the extent to which speed of language comprehension at 1.5 years old predicts both verbal and nonverbal outcomes at 4.5 years old in children born PT. Participants were children born PT (n = 47; ≤32 weeks gestation). Children were tested in the "looking-while-listening" task at 18 months old, adjusted for prematurity, to generate a measure of speed of language comprehension. Parent report and direct assessments of language were also administered. Children were later retested on a test battery of school-relevant skills at 4.5 years old. Speed of language comprehension at 18 months old predicted significant unique variance (12%-31%) in receptive vocabulary, global language abilities, and nonverbal intelligence quotient (IQ) at 4.5 years, controlling for socioeconomic status, gestational age, and medical complications of PT birth. Speed of language comprehension remained uniquely predictive (5%-12%) when also controlling for children's language skills at 18 months old. Individual differences in speed of spoken language comprehension may serve as a marker for neuropsychological processes that are critical for the development of school-relevant linguistic skills and nonverbal IQ in children born PT.

  16. Parapapillary Gamma Zone and Progression of Myopia in School Children: The Beijing Children Eye Study.

    Science.gov (United States)

    Guo, Yin; Liu, Li Juan; Tang, Ping; Feng, Yi; Lv, Yan Yun; Wu, Min; Xu, Liang; Jonas, Jost B

    2018-03-01

    To assess the development and enlargement of the parapapillary gamma zone in school children. This school-based prospective longitudinal study included Chinese children attending grade 1 in 2011 and returning for yearly follow-up examinations until 2016. These examinations consisted of a comprehensive ocular examination with biometry and color fundus photographs. The parents underwent a standardized interview. The parapapillary gamma zone was defined as the area with visible sclera at the temporal optic disc margin, and the optic disc itself was measured on fundus photographs. The study included 294 children (mean age in 2016, 11.4 ± 0.5 years [range, 10-13 years]; mean axial length, 24.1 ± 1.1 mm [range, 21.13-27.29 mm]). In multivariate analysis, larger increases in the gamma zone area during the study period were correlated (coefficient of determination for bivariate analysis [r2], r2 = 0.69) with larger increases in the vertical-to-horizontal disc diameter ratios (P zone area at baseline (P time spent indoors studying (P = 0.015; beta, 0.10; B, 0.09; 95% CI, 0.02-0.17). The development and enlargement of the gamma zone in the temporal parapapillary region were associated with an optic disc rotation around the vertical disc axis as indicated by an increasing vertical-to-horizontal disc diameter ratio. These morphologic findings fit with the notion of a backward pull of the temporal peripapillary sclera through the optic nerve dura mater in axially elongated eyes.

  17. Combinative application of pH-zone-refining and conventional high-speed counter-current chromatography for preparative separation of caged polyprenylated xanthones from gamboge.

    Science.gov (United States)

    Xu, Min; Fu, Wenwei; Zhang, Baojun; Tan, Hongsheng; Xiu, Yanfeng; Xu, Hongxi

    2016-02-01

    An efficient method for the preparative separation of four structurally similar caged xanthones from the crude extracts of gamboge was established, which involves the combination of pH-zone-refining counter-current chromatography and conventional high-speed counter-current chromatography for the first time. pH-zone-refining counter-current chromatography was performed with the solvent system composed of n-hexane/ethyl acetate/methanol/water (7:3:8:2, v/v/v/v), where 0.1% trifluoroacetic acid was added to the upper organic stationary phase as a retainer and 0.03% triethylamine was added to the aqueous mobile phase as an eluter. From 3.157 g of the crude extract, 1.134 g of gambogic acid, 180.5 mg of gambogenic acid and 572.9 mg of a mixture of two other caged polyprenylated xanthones were obtained. The mixture was further separated by conventional high-speed counter-current chromatography with a solvent system composed of n-hexane/ethyl acetate/methanol/water (5:5:10:5, v/v/v/v) and n-hexane/methyl tert-butyl ether/acetonitrile/water (8:2:6:4,v/v/v/v), yielding 11.6 mg of isogambogenic acid and 10.4 mg of β-morellic acid from 218.0 mg of the mixture, respectively. The purities of all four of the compounds were over 95%, as determined by high-performance liquid chromatography, and the chemical structures of the four compounds were confirmed by electrospray ionization mass spectrometry and NMR spectroscopy. The combinative application of pH-zone-refining counter-current chromatography and conventional high-speed counter-current chromatography shows great advantages in isolating and enriching the caged polyprenylated xanthones. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Application of Total Quality Management (TQM) in Secondary School Administration in Umuahia Education Zone

    Science.gov (United States)

    Ejionueme, L. K.; Oyoyo, Anthonia Oluchi

    2015-01-01

    The study was conducted to investigate the application of Total Quality Management (TQM) in secondary school administration in Umuahia Education Zone. Three research questions and one null hypothesis guided the study. Descriptive survey design was employed for the study. The population of the study comprised 1365 administrators. Multi-stage…

  19. Dynamic Speed Adaptation for Path Tracking Based on Curvature Information and Speed Limits.

    Science.gov (United States)

    Gámez Serna, Citlalli; Ruichek, Yassine

    2017-06-14

    A critical concern of autonomous vehicles is safety. Different approaches have tried to enhance driving safety to reduce the number of fatal crashes and severe injuries. As an example, Intelligent Speed Adaptation (ISA) systems warn the driver when the vehicle exceeds the recommended speed limit. However, these systems only take into account fixed speed limits without considering factors like road geometry. In this paper, we consider road curvature with speed limits to automatically adjust vehicle's speed with the ideal one through our proposed Dynamic Speed Adaptation (DSA) method. Furthermore, 'curve analysis extraction' and 'speed limits database creation' are also part of our contribution. An algorithm that analyzes GPS information off-line identifies high curvature segments and estimates the speed for each curve. The speed limit database contains information about the different speed limit zones for each traveled path. Our DSA senses speed limits and curves of the road using GPS information and ensures smooth speed transitions between current and ideal speeds. Through experimental simulations with different control algorithms on real and simulated datasets, we prove that our method is able to significantly reduce lateral errors on sharp curves, to respect speed limits and consequently increase safety and comfort for the passenger.

  20. The role of visual processing speed in reading speed development.

    Science.gov (United States)

    Lobier, Muriel; Dubois, Matthieu; Valdois, Sylviane

    2013-01-01

    A steady increase in reading speed is the hallmark of normal reading acquisition. However, little is known of the influence of visual attention capacity on children's reading speed. The number of distinct visual elements that can be simultaneously processed at a glance (dubbed the visual attention span), predicts single-word reading speed in both normal reading and dyslexic children. However, the exact processes that account for the relationship between the visual attention span and reading speed remain to be specified. We used the Theory of Visual Attention to estimate visual processing speed and visual short-term memory capacity from a multiple letter report task in eight and nine year old children. The visual attention span and text reading speed were also assessed. Results showed that visual processing speed and visual short term memory capacity predicted the visual attention span. Furthermore, visual processing speed predicted reading speed, but visual short term memory capacity did not. Finally, the visual attention span mediated the effect of visual processing speed on reading speed. These results suggest that visual attention capacity could constrain reading speed in elementary school children.

  1. The role of visual processing speed in reading speed development.

    Directory of Open Access Journals (Sweden)

    Muriel Lobier

    Full Text Available A steady increase in reading speed is the hallmark of normal reading acquisition. However, little is known of the influence of visual attention capacity on children's reading speed. The number of distinct visual elements that can be simultaneously processed at a glance (dubbed the visual attention span, predicts single-word reading speed in both normal reading and dyslexic children. However, the exact processes that account for the relationship between the visual attention span and reading speed remain to be specified. We used the Theory of Visual Attention to estimate visual processing speed and visual short-term memory capacity from a multiple letter report task in eight and nine year old children. The visual attention span and text reading speed were also assessed. Results showed that visual processing speed and visual short term memory capacity predicted the visual attention span. Furthermore, visual processing speed predicted reading speed, but visual short term memory capacity did not. Finally, the visual attention span mediated the effect of visual processing speed on reading speed. These results suggest that visual attention capacity could constrain reading speed in elementary school children.

  2. Plastic Zone Analysis of Deep-Buried, Noncircular Tunnel and Application on the High-Speed Railway in the Karst Area

    Directory of Open Access Journals (Sweden)

    Hai Shi

    2017-01-01

    Full Text Available With the conformal mapping function provided by Verruijt, the outland of a noncircular tunnel can be mapped to a circular unit in the complex plane and then spread the analytic function into a Laurent series. The stress unified solution of oval and horseshoe cross section can be determined using Muskhelishvili’s complex variables function method. Subsequently, the solution can be taken into the Griffith strength failure criterion and determine the scale and shape of plastic zone in the tunnel surrounding rock. Aiming at the critical safety thickness between a concealed cave and tunnel in the karst area and determining whether the plastic zone of tunnel surrounding rock is connected with the plastic zone of cave as a judgment standard, the model of critical safety thickness among the concealed caves and tunnels is established. The numerical model is established in comparison with the computing method of rock plate critical safety thickness in actual engineering based on the Doumo tunnel engineering of Shanghai-Kunming (Guizhou segment high-speed railway. The following conclusions can be drawn: the analytical approximation method has less indexes, and the output of this method is approximately close to actual engineering and numerical analysis, in which it is reliable and rational.

  3. TOMOGRAPHY OF PLASMA FLOWS IN THE UPPER SOLAR CONVECTION ZONE USING TIME-DISTANCE INVERSION COMBINING RIDGE AND PHASE-SPEED FILTERING

    International Nuclear Information System (INIS)

    Švanda, Michal

    2013-01-01

    The consistency of time-distance inversions for horizontal components of the plasma flow on supergranular scales in the upper solar convection zone is checked by comparing the results derived using two k-ω filtering procedures—ridge filtering and phase-speed filtering—commonly used in time-distance helioseismology. I show that both approaches result in similar flow estimates when finite-frequency sensitivity kernels are used. I further demonstrate that the performance of the inversion improves (in terms of a simultaneously better averaging kernel and a lower noise level) when the two approaches are combined together in one inversion. Using the combined inversion, I invert for horizontal flows in the upper 10 Mm of the solar convection zone. The flows connected with supergranulation seem to be coherent only for the top ∼5 Mm; deeper down there is a hint of change of the convection scales toward structures larger than supergranules

  4. Evaluation of mobile work zone alarm systems.

    Science.gov (United States)

    2014-06-01

    Maintenance of highways often involves mobile work zones for various types of low speed moving operations such as : striping and sweeping. The speed differential between the moving operation and traffic, and the increasing problem of : distracted dri...

  5. High-Power Laser Cutting of Steel Plates: Heat Affected Zone Analysis

    Directory of Open Access Journals (Sweden)

    Imed Miraoui

    2016-01-01

    Full Text Available The thermal effect of CO2 high-power laser cutting on cut surface of steel plates is investigated. The effect of the input laser cutting parameters on the melted zone depth (MZ, the heat affected zone depth (HAZ, and the microhardness beneath the cut surface is analyzed. A mathematical model is developed to relate the output process parameters to the input laser cutting parameters. Three input process parameters such as laser beam diameter, cutting speed, and laser power are investigated. Mathematical models for the melted zone and the heat affected zone depth are developed by using design of experiment approach (DOE. The results indicate that the input laser cutting parameters have major effect on melted zone, heat affected zone, and microhardness beneath cut surface. The MZ depth, the HAZ depth, and the microhardness beneath cut surface increase as laser power increases, but they decrease with increasing cutting speed. Laser beam diameter has a negligible effect on HAZ depth but it has a remarkable effect on MZ depth and HAZ microhardness. The melted zone depth and the heat affected zone depth can be reduced by increasing laser cutting speed and decreasing laser power and laser beam diameter.

  6. Determining Level of Service for Multilane Median Opening Zone

    Science.gov (United States)

    Ali, Paydar; Johnnie, Ben-Edigbe

    2017-08-01

    The road system is a capital-intensive investment, requiring thorough schematic framework and funding. Roads are built to provide an intrinsic quality of service which satisfies the road users. Roads that provide good services are expected to deliver operational performance that is consistent with their design specifications. Level of service and cumulative percentile speed distribution methods have been used in previous studies to estimate the quality of multilane highway service. Whilst the level of service approach relies on speed/flow curve, the cumulative percentile speed distribution is based solely speed. These estimation methods were used in studies carried out in Johor Malaysia. The aim of the studies is to ascertain the extent of speed reduction caused by midblock U-turn facilities as well as verify which estimation method is more reliable. At selected sites, road segments for both directional flows were divided into free-flow and midblock zones. Traffic volume, speed and vehicle type data for each zone were collected continuously for six weeks. Both estimation methods confirmed that speed reduction would be caused by midblock u-turn facilities. However level of service methods suggested that the quality of service would improve from level F to E or D at midblock zone in spite of speed reduction. Level of service was responding to traffic volume reduction at midblock u-turn facility not travel speed reduction. The studies concluded that since level of service was more responsive to traffic volume reduction than travel speed, it cannot be solely relied upon when assessing the quality of multilane highway service.

  7. An Investigation on Elementary School Students' Level of Math Learning, Using Math E-Books (A Case Study: Pishtazan Computer Primary School, 4th Zone of Tehran

    Directory of Open Access Journals (Sweden)

    Arezoo Naseri

    2016-11-01

    Full Text Available Since the focus on technology exists in all schools and classes, teachers need to know how to apply it in their teaching practices. The use of ICT in education is an undeniable necessity. Since the use of information and communication technology can smooth the paths of teaching-learning process for students, the researchers in this study tried to apply one of the information and communication technology tools, called electronic books (E-books in teaching math. The aim of this study is to examine elementary school students' level of math learning, using math e-books with the focus on teaching multiplication (Case Study: Pishtazan computer primary school, the 4th zone of Tehran. Using a quasi-experimental study, 61 third grade students from two primary schools for girls located in the 4th education zone of Tehran were selected. Math tests were used to collect data. Using T-test for independent samples, the results showed that level of math learning was higher in the students who have been trained with the help of e-book, compared to the students who have been trained through traditional teaching method.

  8. Work zone variable speed limit systems: Effectiveness and system design issues.

    Science.gov (United States)

    2010-03-01

    Variable speed limit (VSL) systems have been used in a number of countries, particularly in Europe, as a method to improve flow and increase safety. VSLs use detectors to collect data on current traffic and/or weather conditions. Posted speed limits ...

  9. Low visual information-processing speed and attention are predictors of fatigue in elementary and junior high school students.

    Science.gov (United States)

    Mizuno, Kei; Tanaka, Masaaki; Fukuda, Sanae; Yamano, Emi; Shigihara, Yoshihito; Imai-Matsumura, Kyoko; Watanabe, Yasuyoshi

    2011-06-14

    Fatigue is a common complaint among elementary and junior high school students, and is known to be associated with reduced academic performance. Recently, we demonstrated that fatigue was correlated with decreased cognitive function in these students. However, no studies have identified cognitive predictors of fatigue. Therefore, we attempted to determine independent cognitive predictors of fatigue in these students. We performed a prospective cohort study. One hundred and forty-two elementary and junior high school students without fatigue participated. They completed a variety of paper-and-pencil tests, including list learning and list recall tests, kana pick-out test, semantic fluency test, figure copying test, digit span forward test, and symbol digit modalities test. The participants also completed computerized cognitive tests (tasks A to E on the modified advanced trail making test). These cognitive tests were used to evaluate motor- and information-processing speed, immediate and delayed memory function, auditory and visual attention, divided and switching attention, retrieval of learned material, and spatial construction. One year after the tests, a questionnaire about fatigue (Japanese version of the Chalder Fatigue Scale) was administered to all the participants. After the follow-up period, we confirmed 40 cases of fatigue among 118 students. In multivariate logistic regression analyses adjusted for grades and gender, poorer performance on visual information-processing speed and attention tasks was associated with increased risk of fatigue. Reduced visual information-processing speed and poor attention are independent predictors of fatigue in elementary and junior high school students. © 2011 Mizuno et al; licensee BioMed Central Ltd.

  10. Low visual information-processing speed and attention are predictors of fatigue in elementary and junior high school students

    Directory of Open Access Journals (Sweden)

    Yamano Emi

    2011-06-01

    Full Text Available Abstract Background Fatigue is a common complaint among elementary and junior high school students, and is known to be associated with reduced academic performance. Recently, we demonstrated that fatigue was correlated with decreased cognitive function in these students. However, no studies have identified cognitive predictors of fatigue. Therefore, we attempted to determine independent cognitive predictors of fatigue in these students. Methods We performed a prospective cohort study. One hundred and forty-two elementary and junior high school students without fatigue participated. They completed a variety of paper-and-pencil tests, including list learning and list recall tests, kana pick-out test, semantic fluency test, figure copying test, digit span forward test, and symbol digit modalities test. The participants also completed computerized cognitive tests (tasks A to E on the modified advanced trail making test. These cognitive tests were used to evaluate motor- and information-processing speed, immediate and delayed memory function, auditory and visual attention, divided and switching attention, retrieval of learned material, and spatial construction. One year after the tests, a questionnaire about fatigue (Japanese version of the Chalder Fatigue Scale was administered to all the participants. Results After the follow-up period, we confirmed 40 cases of fatigue among 118 students. In multivariate logistic regression analyses adjusted for grades and gender, poorer performance on visual information-processing speed and attention tasks was associated with increased risk of fatigue. Conclusions Reduced visual information-processing speed and poor attention are independent predictors of fatigue in elementary and junior high school students.

  11. Household food insecurity and its association with school absenteeism among primary school adolescents in Jimma zone, Ethiopia.

    Science.gov (United States)

    Tamiru, Dessalegn; Argaw, Alemayehu; Gerbaba, Mulusew; Ayana, Girmay; Nigussie, Aderajew; Belachew, Tefera

    2016-08-17

    Household food insecurity and lack of education are two of the most remarkable deprivations which developing countries are currently experiencing. Evidences from different studies showed that health and nutrition problems are major barriers to educational access and achievement in low-income countries which poses a serious challenge on effort towards the achieving Sustainable Development Goals. Evidence on the link between food security and school attendance is very important to address this challenge. This study aimed to assess to what extent food insecurity affects school absenteeism among primary school adolescents. A school based cross-sectional study was conducted among primary school adolescents in Jimma zone from October-November, 2013. Structured questionnaire was used to collect data on the household food security and socio-demographic variables. Data were analyzed using SPSS for windows version 16.0 after checking for missing values and outliers. Multivariable logistic regression analyses were used to determine the association of school absenteeism and food insecurity with independent variables using odds ratio and 95 % of confidence intervals. Variables with p ≤ 0.25 in the bivariate analyses were entered into a multivariable regression analysis to control for associations among the independent variables. The frequency of adolescent school absenteeism was significantly high (50.20 %) among food insecure households (P absenteeism. Household food insecurity was positively associated with lack of maternal education [AOR = 2.26 (0.57, 8.93)] and poor household economic status [AOR = 1.39 (1.18, 2.83)]. However, livestock ownership [AOR = 0.17 (0.06, 0.51)] was negatively associated with household food insecurity. Findings of this study showed that household food insecurity has strong linkage with adolescent school absenteeism. Maternal education and household economic status were significantly associated with household food security

  12. Reduction of speed in work zones using ITS DMS instant feedback to drivers : vehicle speed versus traffic fine.

    Science.gov (United States)

    2014-08-01

    Accidents in work zones produced 17 fatalities in Arizona and 840 fatalities and over 40,000 injuries : nationally in 2009. Motorists nationwide can expect to drive through one active work zone for every 100 : miles driven on the National Highway Sys...

  13. Reduced endogenous Ca2+ buffering speeds active zone Ca2+ signaling.

    Science.gov (United States)

    Delvendahl, Igor; Jablonski, Lukasz; Baade, Carolin; Matveev, Victor; Neher, Erwin; Hallermann, Stefan

    2015-06-09

    Fast synchronous neurotransmitter release at the presynaptic active zone is triggered by local Ca(2+) signals, which are confined in their spatiotemporal extent by endogenous Ca(2+) buffers. However, it remains elusive how rapid and reliable Ca(2+) signaling can be sustained during repetitive release. Here, we established quantitative two-photon Ca(2+) imaging in cerebellar mossy fiber boutons, which fire at exceptionally high rates. We show that endogenous fixed buffers have a surprisingly low Ca(2+)-binding ratio (∼ 15) and low affinity, whereas mobile buffers have high affinity. Experimentally constrained modeling revealed that the low endogenous buffering promotes fast clearance of Ca(2+) from the active zone during repetitive firing. Measuring Ca(2+) signals at different distances from active zones with ultra-high-resolution confirmed our model predictions. Our results lead to the concept that reduced Ca(2+) buffering enables fast active zone Ca(2+) signaling, suggesting that the strength of endogenous Ca(2+) buffering limits the rate of synchronous synaptic transmission.

  14. Determining the drivers' acceptance of EFTCD in highway work zones.

    Science.gov (United States)

    Bai, Yong; Li, Yingfeng

    2011-05-01

    Traffic safety is a major concern in the temporary one-lane, two-way highway work zones due to the increasing of construction and maintenance operations. To prevent rear-end crashes and to mitigate the severity of these crashes caused by the inattentive driving, the utilization of the Emergency Flasher Traffic Control Device (EFTCD) was under consideration by government agencies, in addition to existing temporary traffic control devices installed in the one-lane, two-way highway work zones. The EFTCD was a newly proposed traffic warning device implemented through the use of vehicles' hazard warning flashers. The primary objective of the research project was to investigate the drivers' acceptance of the proposed EFTCD by measuring the mean speed changes of vehicles with and without EFTCD and by evaluating the drivers' opinions of the EFTCD using the survey method. Field experimental results revealed that the EFTCD effectively reduced the mean vehicle speeds in the upstream of two work zones. A slow speed is more likely to reduce the severity of a crash in work zones. In addition, survey results indicated that 60% of the drivers thought the EFTCD signified a need for speed reduction and 82% of drivers recommended the implementation of the EFTCD in one-lane, two-way work zones. These results provide the necessary scientific justifications for the government agencies to decide if the EFTCD should be implemented in the one-lane, two-way highway work zones to prevent rear-end crashes and to mitigate the severity of these crashes. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Age-related changes in crowding and reading speed

    OpenAIRE

    Liu, Rong; Patel, Bhavika N.; Kwon, MiYoung

    2017-01-01

    Crowding, the inability to recognize objects in clutter, is known to play a role in developmental changes in reading speed. Here, we investigated whether crowding also plays a role in age-related changes in reading speed. We recruited 18 young (mean age: 22.6???3.5; range: 18~31) and 21 older adults (mean age: 58.2???7.0; range: 50~73) with normal vision. Reading speed was measured with short blocks of text. The degree of crowding was determined by measuring crowding zone (the distance betwee...

  16. Comparative studies on control systems for a two-blade variable-speed wind turbine with a speed exclusion zone

    International Nuclear Information System (INIS)

    Yang, Jian; Song, Dongran; Dong, Mi; Chen, Sifan; Zou, Libing; Guerrero, Josep M.

    2016-01-01

    To avoid the coincidence between the tower nature frequency and rotational excitation frequency, a SEZ (speed exclusion zone) must be built for a two-blade wind turbine with a full rated converter. According to the literature, two methods of SEZ-crossing could be adopted. However, none of them have been studied in industrial applications, and their performance remains unclear. Moreover, strategies on power regulation operation are not covered. To fully investigate them, this paper develops two control systems for a two-blade WT (wind turbines) with a SEZ. Because control systems play vital roles in determining the performance of the WT, this paper focuses on comparative studies on their operation strategies and performance. In these strategies, optimal designs are introduced to improve existing SEZ algorithms. Moreover, to perform power regulation outside the SEZ, two operation modes are divided in the proposed down power regulation solutions. The developed control systems’ performance is confirmed by simulations and field tests. Two control systems present similar capabilities of power production and SEZ-bridging. Nevertheless, at the cost of significantly increased tower loads, one captures 1% more energy than the other. Overall consideration must be made for the control system selection for a WT with a SEZ. - Highlights: • Two control systems are developed for a two-blade WT with a SEZ. • Three strategies, that is, power optimization, power limitation and power regulation, are discussed. • Optimal designs are adopted to enhance the WT's SEZ-bridging capability. • Simple but effective power regulation solutions are presented. • Simulation and field test results show that Control System 2 produces 1% more energy at the cost of increased tower loads.

  17. Conservation Abilities, Visuospatial Skills, and Numerosity Processing Speed: Association with Math Achievement and Math Difficulties in Elementary School Children

    Science.gov (United States)

    Lambert, Katharina; Spinath, Birgit

    2018-01-01

    The aim of the present study was to investigate the associations between elementary school children's mathematical achievement and their conservation abilities, visuospatial skills, and numerosity processing speed. We also assessed differences in these abilities between children with different types of learning problems. In Study 1 (N = 229), we…

  18. Nugget Structure Evolution with Rotation Speed for High-Rotation-Speed Friction-Stir-Welded 6061 Aluminum Alloy

    Science.gov (United States)

    Zhang, H. J.; Wang, M.; Zhu, Z.; Zhang, X.; Yu, T.; Wu, Z. Q.

    2018-03-01

    High-rotation-speed friction stir welding (HRS-FSW) is a promising technique to reduce the welding loads during FSW and thus facilitates the application of FSW for in situ fabrication and repair. In this study, 6061 aluminum alloy was friction stir welded at high-rotation speeds ranging from 3000 to 7000 rpm at a fixed welding speed of 50 mm/min, and the effects of rotation speed on the nugget zone macro- and microstructures were investigated in detail in order to illuminate the process features. Temperature measurements during HRS-FSW indicated that the peak temperature did not increase consistently with rotation speed; instead, it dropped remarkably at 5000 rpm because of the lowering of material shear stress. The nugget size first increased with rotation speed until 5000 rpm and then decreased due to the change of the dominant tool/workpiece contact condition from sticking to sliding. At the rotation speed of 5000 rpm, where the weld material experienced weaker thermal effect and higher-strain-rate plastic deformation, the nugget exhibited relatively small grain size, large textural intensity, and high dislocation density. Consequently, the joint showed superior nugget hardness and simultaneously a slightly low tensile ductility.

  19. Curriculum Package: Junior High - Middle School Science Lessons. [A Visit to the Louisville, Kentucky Airports: Standiford and Bowman Fields.

    Science.gov (United States)

    Squires, Frances H.

    This science curriculum was written for teachers of children in junior high or middle school. It contains science activities for the following lessons: (1) Anemometers and Wind Speed; (2) Up! Up! and Away; (3) Jet Lag--Time Zones; (4) Inventors; (5) Model Rocketry; (6) Geometry and Kites; and (7) Super Savers. In lesson one, students construct an…

  20. Tensile Properties of Friction Stir Welded Joints of AA 2024-T6 Alloy at Different Welding Speeds

    Science.gov (United States)

    Avula, Dhananjayulu; Devuri, Venkateswarlu; Cheepu, Muralimohan; Dwivedi, Dheerendra Kumar

    2018-03-01

    The influence of welding speed on the friction stir welded joint properties of hardness, tensile properties, defects and microstructure characterization are studied in the present study. The friction stir welding was conducted on AA2014-T6 heat treated alloy with 5 mm thickness plate in butt joint configuration. The welding speed was varied from 8 mm/min to 120 mm/min at the fixed travel speed and load conditions. It is observed that the welding speeds at higher rate with wide range can be possible to weld this alloy at higher rates of tool revolution suggesting that the inherent capability of friction stir welding technique for aluminum 2014 alloys. The strength of the joints gradually increases with enhancing of welding speed. The micro structural observations exhibited the formation of equiaxed grains in the stir zone and slightly in the thermo-mechanically affected zone. In addition, the size of the grains decreases with increase in welding speed owing to the presence of low heat input. Hence the hardness of the joints slightly increased in the stir zones over the other zones of the weld nugget. The joint strength initially increases with the welding speed and starts to decreases after reaching to the maximum value. The relationship between the welding conditions and friction stir welded joint properties has been discussed.

  1. SOUND-SPEED INVERSION OF THE SUN USING A NONLOCAL STATISTICAL CONVECTION THEORY

    International Nuclear Information System (INIS)

    Zhang Chunguang; Deng Licai; Xiong Darun; Christensen-Dalsgaard, Jørgen

    2012-01-01

    Helioseismic inversions reveal a major discrepancy in sound speed between the Sun and the standard solar model just below the base of the solar convection zone. We demonstrate that this discrepancy is caused by the inherent shortcomings of the local mixing-length theory adopted in the standard solar model. Using a self-consistent nonlocal convection theory, we construct an envelope model of the Sun for sound-speed inversion. Our solar model has a very smooth transition from the convective envelope to the radiative interior, and the convective energy flux changes sign crossing the boundaries of the convection zone. It shows evident improvement over the standard solar model, with a significant reduction in the discrepancy in sound speed between the Sun and local convection models.

  2. Seroprevalence and sociocultural conditionants of Chagas disease in school aged children of marginal zones of Asunción

    Directory of Open Access Journals (Sweden)

    Vera Ninfa I.

    1998-01-01

    Full Text Available Chagas disease is becoming a public health problem in Latin America due to the wide distribution, the high prevalence, the magnitude of the damage caused and the difficulties to control it. In Paraguay, the disease is mainly distributed in the departments of Paraguari, Cordillera and Central. Prevalence in marginal zones, where migrations from rural populations and endemic areas make possible the urbanization of the disease, has no been studied yet. This is a descriptive study with a cross-sectional sampling and a probabilistic system recruitment carried out in school aged children from marginal zones of Asuncion to determine the prevalence of Chagas' disease. Serological methods, parasite isolation and questionnaires were used to achieve the goals. Nine hundred and fifty three children were studied to determine the prevalence of Chagas' disease in marginal zones which was 1.4%.

  3. Precision increase in electric drive speed loop of robotic complexes and process lines

    Science.gov (United States)

    Tulegenov, E.; Imanova, A. A.; Platonov, V. V.

    2018-05-01

    The article presents the principles of synthesis of control structures for highprecision electric drives of robotic complexes and manipulators. It has been theoretically shown and experimentally confirmed that improved characteristics of speed maintenance in the zone of significant overloads are achieved in systems of series excitation. They are achieved due to the redistribution of control signals both in the zone of setting the armature current and in the excitation currents. At the same time, the characteristic of the electromagnetic torque becomes linear because the demagnetizing effect of the armature response is compensated by the setting of the excitation current. It is recommended in those cases when it is necessary to extend the range of speed control with a significant reduction in load to apply structures with two-zone speed control. The regulation of the weakening of the excitation flow is more convenient as a function of the voltage in the armature windings.

  4. Rotor aerodynamic power limits at low tip speed ratio using CFD

    DEFF Research Database (Denmark)

    Mikkelsen, Robert Flemming; Sarmast, Sasan; Henningson, Dan

    2014-01-01

    . In the present work we study in detail, using a CFD actuator line model, the flow behavior for rotors at small tip speed ratios. It is shown that the excessive swirl appearing towards the rotor center at small tip speed ratios generates vortex breakdown, causing a recirculating zone in the wake that limits...

  5. Conservation Abilities, Visuospatial Skills, and Numerosity Processing Speed: Association With Math Achievement and Math Difficulties in Elementary School Children.

    Science.gov (United States)

    Lambert, Katharina; Spinath, Birgit

    The aim of the present study was to investigate the associations between elementary school children's mathematical achievement and their conservation abilities, visuospatial skills, and numerosity processing speed. We also assessed differences in these abilities between children with different types of learning problems. In Study 1 ( N = 229), we investigated second to fourth graders and in Study 2 ( N = 120), third and fourth graders. Analyses revealed significant contributions of numerosity processing speed and visuospatial skills to math achievement beyond IQ. Conservation abilities were predictive in Study 1 only. Children with math difficulties showed lower visuospatial skills and conservation abilities than children with typical achievement levels and children with reading and/or spelling difficulties, whereas children with combined difficulties explicitly showed low conservation abilities. These findings provide further evidence for the relations between children's math skills and their visuospatial skills, conservation abilities, and processing speed and contribute to the understanding of deficits that are specific to mathematical difficulties.

  6. High speed capillary zone electrophoresis-mass spectrometry via an electrokinetically pumped sheath flow interface for rapid analysis of amino acids and a protein digest.

    Science.gov (United States)

    Schiavone, Nicole M; Sarver, Scott A; Sun, Liangliang; Wojcik, Roza; Dovichi, Norman J

    2015-06-01

    While capillary zone electrophoresis (CZE) has been used to produce very rapid and efficient separations, coupling these high-speed separations with mass spectrometry (MS) has been challenging. Now, with much faster and sensitive mass spectrometers, it is possible to take full advantage of the CZE speed and reconstruct the fast migrating peaks. Here are three high-speed CZE-MS analyses via an electrokinetically pumped sheath-flow interface. The first separation demonstrates CZE-ESI-MS of an amino acid mixture with a 2-min separation, >50,000 theoretical plates, low micromolar concentration detection limits, and subfemtomole mass detection limits (LTQ XL mass spectrometer). The second separation with our recently improved third-generation CE-MS interface illustrates a 20 amino acid separation in ∼7min with an average over 200,000 plate counts, and results in almost-baseline resolution of structural isomers, leucine and isoleucine. The third separation is of a BSA digest with a reproducible CZE separation and mass spectrometry detection in 2min. CZE-MS/MS analysis of the BSA digest identified 31 peptides, produced 52% sequence coverage, and generated a peak capacity of ∼40 across the 1-min separation window (Q-Exactive mass spectrometer). Copyright © 2015 Elsevier B.V. All rights reserved.

  7. High-Speed Friction Stir Welding of AA7075-T6 Sheet: Microstructure, Mechanical Properties, Micro-texture, and Thermal History

    Science.gov (United States)

    Zhang, Jingyi; Upadhyay, Piyush; Hovanski, Yuri; Field, David P.

    2018-01-01

    Friction stir welding (FSW) is a cost-effective and high-quality joining process for aluminum alloys (especially heat-treatable alloys) that is historically operated at lower joining speeds (up to hundreds of millimeters per minute). In this study, we present a microstructural analysis of friction stir welded AA7075-T6 blanks with high welding speeds up to 3 M/min. Textures, microstructures, mechanical properties, and weld quality are analyzed using TEM, EBSD, metallographic imaging, and Vickers hardness. The higher welding speed results in narrower, stronger heat-affected zones (HAZs) and also higher hardness in the nugget zones. The material flow direction in the nugget zone is found to be leaning towards the welding direction as the welding speed increases. Results are coupled with welding parameters and thermal history to aid in the understanding of the complex material flow and texture gradients within the welds in an effort to optimize welding parameters for high-speed processing.

  8. Cardiorespiratory demands during an inline speed skating marathon race: a case report.

    Science.gov (United States)

    Stangier, Carolin; Abel, Thomas; Mierau, Julia; Hollmann, Wildor; Strüder, Heiko K

    2016-09-01

    This study was designed to investigate the intensity profile during an inline speed skating marathon road race. A highly-trained male athlete (20 y, 73.4 kg, 178 cm, V̇O2 peak: 60.8 mL·kg-1·min-1) participated in a marathon road race. Oxygen uptake (V̇O2), respiratory exchange ratio (RER), heart rate (HR) and speed were measured using a portable gas analysis system with a HR monitor and GPS-Sensor integrated. The athlete´s peak V̇O2, HR and speed at ventilatory thresholds were assessed during an incremental field test (22 km·h-1, increase 2 km·h-1 every 5 min) one week before the race. During the race, the absolute time spent in the "easy intensity zone" (V̇O2 below VT1) was 1 min, 49 min "moderate intensity zone" (V̇O2 between VT1 and VT2), and 26 min in the "hard intensity zone" (V̇O2 above VT2). The average HR was 171±6 bpm, corresponding to 95% of the maximum. This study shows that inline speed skating road races over a marathon are conducted at moderate to high V̇O2 and heart rate levels. The physiological racing pattern is very intermittent, requiring both a high level of aerobic and anaerobic capacity.

  9. Assessment of freeway work zone safety with improved cellular automata model

    Directory of Open Access Journals (Sweden)

    Guohua Liang

    2014-08-01

    Full Text Available To accurately assess the safety of freeway work zones, this paper investigates the safety of vehicle lane change maneuvers with improved cellular automata model. Taking the traffic conflict and standard deviation of operating speed as the evaluation indexes, the study evaluates the freeway work zone safety. With improved deceleration probability in car-following raies and the addition of lanechanging rules under critical state, the lane-changing behavior under critical state is defined as a conflict count. Through 72 schemes of simulation runs, the possible states of the traffic flow are carefully studied. The results show that under the condition of constant saturation traffic conflict count and vehicle speed standard deviation reach their maximums when the mixed rate of heave vehicles is 40%. Meanwhile, in the case of constant heavy vehicles mix, traffic conflict count and vehicle speed standard deviation reach maximum values when saturation rate is 0. 75. Integrating ail simulation results, it is known the traffic safety in freeway work zones is classified into four levels : safe, relatively safe, relatively dangerous, and dangerous.

  10. TEMA and Dot Enumeration Profiles Predict Mental Addition Problem Solving Speed Longitudinally.

    Science.gov (United States)

    Major, Clare S; Paul, Jacob M; Reeve, Robert A

    2017-01-01

    Different math indices can be used to assess math potential at school entry. We evaluated whether standardized math achievement (TEMA-2 performance), core number abilities (dot enumeration, symbolic magnitude comparison), non-verbal intelligence (NVIQ) and visuo-spatial working memory (VSWM), in combination or separately, predicted mental addition problem solving speed over time. We assessed 267 children's TEMA-2, magnitude comparison, dot enumeration, and VSWM abilities at school entry (5 years) and NVIQ at 8 years. Mental addition problem solving speed was assessed at 6, 8, and 10 years. Longitudinal path analysis supported a model in which dot enumeration performance ability profiles and previous mental addition speed predicted future mental addition speed on all occasions, supporting a componential account of math ability. Standardized math achievement and NVIQ predicted mental addition speed at specific time points, while VSWM and symbolic magnitude comparison did not contribute unique variance to the model. The implications of using standardized math achievement and dot enumeration ability to index math learning potential at school entry are discussed.

  11. Apparatus for obtaining electric energy in speed highways

    International Nuclear Information System (INIS)

    Khalatyan, P.R.; Khalatyan, R.P.; Khalatyan, E.P.

    2012-01-01

    The problems of obtaining electricity by means of moving motor-transport are examined. An apparatus installed in the distributive zone of intensive traffic speed highways is proposed. Part of air mass movement of kinetic energy is transformed from the movement of automobiles into electricity

  12. Naturalistic speeding data: Drivers aged 75 years and older

    Directory of Open Access Journals (Sweden)

    Anna Chevalier

    2016-09-01

    Full Text Available The data presented in this article are related to the research article entitled “A longitudinal investigation of the predictors of older drivers׳ speeding behavior” (Chevalier et al., 2016 [1], wherein these speed events were used to investigate older drivers speeding behavior and the influence of cognition, vision, functional decline, and self-reported citations and crashes on speeding behavior over a year of driving. Naturalistic speeding behavior data were collected for up to 52 weeks from volunteer drivers aged 75–94 years (median 80 years, 52% male living in the suburban outskirts of Sydney. Driving data were collected using an in-vehicle monitoring device. Global Positioning System (GPS data were recorded at each second and determined driving speed through triangulation of satellite collected location data. Driving speed data were linked with mapped speed zone data based on a service-provider database. To measure speeding behavior, speed events were defined as driving 1 km/h or more, with a 3% tolerance, above a single speed limit, averaged over 30 s. The data contains a row per 124,374 speed events. This article contains information about data processing and quality control. Keywords: Older drivers, Speed, Road safety, Naturalistic, In-vehicle monitoring, Device

  13. Control of penetration zone GMAW

    Directory of Open Access Journals (Sweden)

    Віталій Петрович Iванов

    2016-11-01

    Full Text Available Thermal properties of the base metal, shielding medium and the nature of the electrode metal transfer to a great extent determine the penetration area formation in gas-arc welding. It is not always possible to take into account the influence of these factors on penetration front forming within the existing models. The aim of the work was to research the penetration area forming in gas-arc welding. The research of the penetration area forming in gas-arc welding of CrNi austenitic steels was made. The parameters of the regime as well as the kind of the gaseous medium influence on the formation of the penetration zone were studied. The article shows a linear proportional relationship between the electrode feed rate and the size of the base metal plate. The penetration area formation mode for welding in argon and carbon dioxide have been worked out. Diameter, feed rate and the speed of the electrode movement have been chosen as the main input parameters. Multiple regression analysis method was used to make up the modes. The relations of the third order that make it possible to take into account the electrode metal transfer and thermal properties change of the materials to be welded were used. These relationships show quite good agreement with the experimental measurements in the calculation of the fusion zone shape with consumable electrode in argon and carbon dioxide. It was determined that the shape of the melting front curve can be shown as a generalized function in which the front motion parameters depend on feed rate and the diameter of the electrode. Penetration zone growth time is determined by the welding speed and is calculated as a discrete function of the distance from the electrode with the spacing along the movement coordinate. The influence of the mode parameters on the formation of the fusion zone has been investigated and the ways to manage and stabilize the weld pool formation have been identified. The modes can be used to develop

  14. Microstructure characterization of the stir zone of submerged friction stir processed aluminum alloy 2219

    International Nuclear Information System (INIS)

    Feng, Xiuli; Liu, Huijie; Lippold, John C.

    2013-01-01

    Aluminum alloy 2219-T6 was friction stir processed using a novel submerged processing technique to facilitate cooling. Processing was conducted at a constant tool traverse speed of 200 mm/min and spindle rotation speeds in the range from 600 to 800 rpm. The microstructural characteristics of the base metal and processed zone, including grain structure and precipitation behavior, were studied using optical microscopy (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Microhardness maps were constructed on polished cross sections of as-processed samples. The effect of tool rotation speed on the microstructure and hardness of the stir zone was investigated. The average grain size of the stir zone was much smaller than that of the base metal, but the hardness was also lower due to the formation of equilibrium θ precipitates from the base metal θ′ precipitates. Stir zone hardness was found to decrease with increasing rotation speed (heat input). The effect of processing conditions on strength (hardness) was rationalized based on the competition between grain refinement strengthening and softening due to precipitate overaging. - Highlights: • SZ grain size (∼ 1 μm) is reduced by over one order of magnitude relative to the BM. • Hardness in the SZ is lower than that of the precipitation strengthened BM. • Metastable θ′ in the base metal transforms to equilibrium θ in the stir zone. • Softening in the SZ results from a decrease of precipitation strengthening

  15. Microstructure characterization of the stir zone of submerged friction stir processed aluminum alloy 2219

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Xiuli, E-mail: feng.97@osu.edu [Welding Engineering Program, Department of Materials Science and Engineering, The Ohio State University, Columbus, OH 43221 (United States); State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Liu, Huijie, E-mail: liuhj@hit.edu.cn [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Lippold, John C., E-mail: lippold.1@osu.edu [Welding Engineering Program, Department of Materials Science and Engineering, The Ohio State University, Columbus, OH 43221 (United States)

    2013-08-15

    Aluminum alloy 2219-T6 was friction stir processed using a novel submerged processing technique to facilitate cooling. Processing was conducted at a constant tool traverse speed of 200 mm/min and spindle rotation speeds in the range from 600 to 800 rpm. The microstructural characteristics of the base metal and processed zone, including grain structure and precipitation behavior, were studied using optical microscopy (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Microhardness maps were constructed on polished cross sections of as-processed samples. The effect of tool rotation speed on the microstructure and hardness of the stir zone was investigated. The average grain size of the stir zone was much smaller than that of the base metal, but the hardness was also lower due to the formation of equilibrium θ precipitates from the base metal θ′ precipitates. Stir zone hardness was found to decrease with increasing rotation speed (heat input). The effect of processing conditions on strength (hardness) was rationalized based on the competition between grain refinement strengthening and softening due to precipitate overaging. - Highlights: • SZ grain size (∼ 1 μm) is reduced by over one order of magnitude relative to the BM. • Hardness in the SZ is lower than that of the precipitation strengthened BM. • Metastable θ′ in the base metal transforms to equilibrium θ in the stir zone. • Softening in the SZ results from a decrease of precipitation strengthening.

  16. Distribution of dilemma zone after intelligent transportation system established

    Science.gov (United States)

    Deng, Yuanchang; Yang, Huiqin; Wu, Linying

    2017-03-01

    Dilemma zone refers to an area where vehicles can neither clear the intersection during the yellow interval nor stop safely before the stop line. The purpose of this paper is to analyzing the distribution of two types of dilemma zone after intelligent transportation system (ITS) established at Outer Ring Roads signalized intersections in Guangzhou Higher Education Mega Center. To collect field data a drone aircraft was used. When calculating the type II dilemma zone's distribution, we considered the information of drivers' aggressiveness, which was classified by driving speed and type I dilemma zone as well. We also compared the two types dilemma zone's distribution before and after ITS established and analyzed the changes, which was brought by ITS.

  17. Public secondary school teachers' attitude to family life education in two geopolitical zones of Nigeria: a comparative analysis.

    Science.gov (United States)

    Okusanya, B O; Isabu, P A

    2010-03-01

    This qualitative study was conducted to assess and compare the attitude of teachers in two geopolitical zones of Nigeria to family life education. Multi stage sample selection was used to pick 6 public secondary schools (3 junior, 3 senior) in each zone. All teachers (221) in the selected schools were surveyed. Pre-tested questionnaires were self administered, responses analyzed and results presented using descriptive frequencies. Where appropriate statistical evaluation was done with Yates corrected Chi square at 95% confidence interval. Katsina respondents were mostly Muslims (92.4%), married (64.8%) and had the National Certificate of Education (62.9%). Ekpoma teachers were mostly Christians (97.4%), married (93.1%) and 67.2% had a University degree. Attendance at a seminar on family life education was by 19% and 25.9% of respondents from Katsina and Ekpoma respectively. Teachers' knowledge of family life education was very good and most teachers in both regions considered it useful but there were geographical disparities in perception and attitude. While teachers in Katsina discussed HIV/AIDS twice more with their students than sexuality (54.3% vs 28%) those in Ekpoma discussed sexuality more than HIV/AIDS (80.2% vs 72.4%). Respondents in Katsina reported three times (60% vs 19.8%) more that parents would object to FLE in schools than those in Ekpoma and also that its introduction would encourage promiscuity amongst the students (53.3% vs 21.6%). While being married positively influenced respondents' perception, their attitude was influenced positively by having university degree and teaching at the senior secondary school. Christians significantly discussed sexuality (Chi square 58.60; RR: 3.03) and HIV/AIDS (Chi square 15.01; RR: 1.50) with students than Muslims. Policy makers need to be aware of the regional differences in teachers' attitude to family life education as this may hinder the implementation of curriculum.

  18. 40 CFR Appendix III to Part 1042 - Not-to-Exceed Zones

    Science.gov (United States)

    2010-07-01

    ... CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE MARINE COMPRESSION-IGNITION ENGINES AND VESSELS Pt. 1042... engines certified using the duty cycle specified in § 1042.505(b)(1), except for variable-speed propulsion... Appendix illustrates the default NTE zone for variable-speed marine engines used with controllable-pitch...

  19. Prevalence of Schistosoma mansoni infection and the therapeutic efficacy of praziquantel among school children in Manna District, Jimma Zone, southwest Ethiopia

    Directory of Open Access Journals (Sweden)

    Mitiku Bajiro

    2016-10-01

    Full Text Available Abstract Background Intestinal schistosomiasis is one of the neglected tropical parasitic diseases caused by Schistosoma mansoni. Currently, the control measures for the disease are mainly based on mass drug administration (MDA with praziquantel (PZQ targeting the school-age children. In Ethiopia, the potential foci for schistosomiasis and therapeutic efficacy of PZQ among school-age children remain poorly explored. Therefore, we determined both the prevalence and intensity of S. mansoni infection and the therapeutic efficacy of PZQ among school children in the Manna District (new foci for S. mansoni, Jimma Zone, southwest Ethiopia. Methods A cross-sectional study was conducted among the school children aged between 6 and 18 years in three primary schools in Manna district from March to April 2014. For diagnosis of S. mansoni, a single stool sample was obtained from each child and processed using single Kato Katz and examined under light microscopy. A questionnaire was used to collect demographic information of the school children participated in the study. School children excreting eggs of S. mansoni were administered with 40 mg/kg of PZQ and re-examined after three weeks post-treatment. The therapeutic efficacy of PZQ against S. mansoni was evaluated by means of cure rate and egg reduction rate. Results The overall prevalence of S. mansoni among the school children in the three primary schools in Manna District was 24.0 %. Higher prevalence was recorded for males 25.6 % (61/238 than for females 22.5 % (59/262. Majority (27.5 % of infection intensity was light with mean faecal egg count (FEC of 202 eggs per gram (EPG. The therapeutic efficacy of PZQ at a dose of 40 mg/kg was highly efficient (cure rate of 99.1 % and egg reduction rate of 99.9 % among the school children in the three primary schools in Manna District. Conclusions The school children in the three primary schools of Manna District, Jimma Zone were at moderate risk of the

  20. Analysis Links Zoning Policies and Disparities

    Science.gov (United States)

    Shah, Nirvi

    2012-01-01

    Location, location, location. This mantra of real estate agents and their clients alike is now the target of a new report from the Brookings Institution linking housing prices and zoning practices to effectively depriving low-income students of high-quality schools. Using test scores from schools in the 100 largest metropolitan areas in the…

  1. Are retailers compliant with zoning regulations that ban tobacco sales near schools in Changsha, China?

    Science.gov (United States)

    Wang, Ling; Lu, Bo; Wewers, Mary Ellen; Foraker, Randi E; Xie, Mengyao; Ferketich, Amy K

    2017-07-01

    Tobacco retail sales are prohibited within 100 m of schools in many large cities in China. However, little is known about the enforcement of this zoning regulation. The objectives of this study were to estimate tobacco retailers' compliance with the regulation, examine the density of tobacco retail stores, describe the types of tobacco products sold in stores and how they are marketed, and determine if there are displays of warning messages in retail stores around schools and in neighbourhoods in Changsha, China. Tobacco retail stores located within 200 m of 36 schools and 36 residential neighbourhoods were audited by trained students with a validated audit form. On average, there were about 3 tobacco retail stores within 100 m of the front entrance of schools. The density of the stores and the types of tobacco products sold in the stores were similar near schools and in neighbourhoods. Over one-fourth of the stores had exterior tobacco advertisements. Interior advertising was slightly less prevalent, and it was most prevalent among tobacco shops (62.5%). Tobacco displays that target children were pervasive, with about 83% of tobacco retail stores displaying cigarettes within 1 m of the floor and 59% displaying cigarettes within 0.3 m of toys and candy. About 40% of stores within 100 m of a school had a visible retail licence. Only 19.6% of the stores had a 'smoke-free' sign and 22.2% had a 'no sales to minors' sign. We observed low enforcement of the regulation that bans tobacco retail sales near schools and high prevalence of tobacco displays that target children in Changsha, China. Chinese officials should act to effectively enforce the regulation bans of tobacco sales near schools. In addition, regulations are urgently needed to limit tobacco marketing practices at the point of sale, especially those targeting youth. 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/.

  2. Historicizing Teaching in Awgni as a Mother Tongue Language at Primary Schools of Awi Nationality Administrative Zone: Challenges and Implementation

    Science.gov (United States)

    Engida, Alemayehu Erkihun

    2015-01-01

    This study examined the challenges facing the teaching as well as the implementation of Awgni as a mother tongue language in primary schools of Awi administrative zone. The need to teach through mother tongue in Ethiopia was widely discussed following the change of the politics in 1991. To this end, the government issued new education and training…

  3. Two-phase modeling of DDT: Structure of the velocity-relaxation zone

    International Nuclear Information System (INIS)

    Kapila, A.K.; Son, S.F.; Bdzil, J.B.; Menikoff, R.; Stewart, D.S.

    1997-01-01

    The structure of the velocity relaxation zone in a hyperbolic, nonconservative, two-phase model is examined in the limit of large drag, and in the context of the problem of deflagration-to-detonation transition in a granular explosive. The primary motivation for the study is the desire to relate the end states across the relaxation zone, which can then be treated as a discontinuity in a reduced, equivelocity model, that is computationally more efficient than its parent. In contrast to a conservative system, where end states across thin zones of rapid variation are determined principally by algebraic statements of conservation, the nonconservative character of the present system requires an explicit consideration of the structure. Starting with the minimum admissible wave speed, the structure is mapped out as the wave speed increases. Several critical wave speeds corresponding to changes in the structure are identified. The archetypal structure is partly dispersed, monotonic, and involves conventional hydrodynamic shocks in one or both phases. The picture is reminiscent of, but more complex than, what is observed in such (simpler) two-phase media as a dusty gas. copyright 1997 American Institute of Physics

  4. The impact of vessel speed reduction on port accidents.

    Science.gov (United States)

    Chang, Young-Tae; Park, Hyosoo

    2016-03-19

    Reduced-speed zones (RSZs) have been designated across the world to control emissions from ships and prevent mammal strikes. While some studies have examined the effectiveness of speed reduction on emissions and mammal preservation, few have analyzed the effects of reduced ship speed on vessel safety. Those few studies have not yet measured the relationship between vessel speed and accidents by using real accident data. To fill this gap in the literature, this study estimates the impact of vessel speed reduction on vessel damages, casualties and frequency of vessel accidents. Accidents in RSZ ports were compared to non-RSZ ports by using U.S. Coast Guard data to capture the speed reduction effects. The results show that speed reduction influenced accident frequency as a result of two factors, the fuel price and the RSZ designation. Every $10 increase in the fuel price led to a 10.3% decrease in the number of accidents, and the RSZ designation reduced vessel accidents by 47.9%. However, the results do not clarify the exact impact of speed reduction on accident casualty. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Influence of Scanning Speed on the Microhardness Property of ...

    African Journals Online (AJOL)

    Akorede

    manufacturing method for processing titanium alloys for aerospace ... through laser metal deposition of Ti6Al4V powder on. Ti6Al4V substrate. II. .... and the microstructures of the clad zone of samples at different scanning speeds are shown in ...

  6. A CDT-Based Heuristic Zone Design Approach for Economic Census Investigators

    Directory of Open Access Journals (Sweden)

    Changixu Cheng

    2015-01-01

    Full Text Available This paper addresses a special zone design problem for economic census investigators that is motivated by a real-world application. This paper presented a heuristic multikernel growth approach via Constrained Delaunay Triangulation (CDT. This approach not only solved the barriers problem but also dealt with the polygon data in zoning procedure. In addition, it uses a new heuristic method to speed up the zoning process greatly on the premise of the required quality of zoning. At last, two special instances for economic census were performed, highlighting the performance of this approach.

  7. Effect of welding parameters (plunge depths of shoulder, pin geometry, and tool rotational speed) on the failure mode and stir zone characteristics of friction stir spot welded aluminum 2024-T3 sheets

    Energy Technology Data Exchange (ETDEWEB)

    Paidar, Moslem; Sarab, Mahsa Lali; Taheri, Morteza; Khodabandeh, Alireza [Islamic Azad University, Tehran (Iran, Islamic Republic of)

    2015-11-15

    The main purpose of this study was to investigate the effect of welding parameters on the failure mode and stir zone characteristics of aluminum alloy 2024-T3 joined by friction stir spot welding. The welding parameters in this work are tool rotational speed, plunge depths of shoulder, and pin geometry. In accordance with the methods of previous investigations, the rotational speeds were set to 630 rpm to 2000 rpm. Two pin geometries with concave shoulder were used: triangular and cylindrical. The plunge depths of the shoulder were 0.3, 0.5 and 0.7 mm. The shoulder diameter and pin height for both geometries were 14 and 2.4 mm, respectively. The diameter of the cylindrical and triangular pins was 5 mm. Results show that the parameters mentioned earlier influence fracture mode under tension shear loading. Two different fracture modes were observed during the examinations. Low-penetration depths and low-rotational speeds lead to shear fracture, whereas high values of these factors cause the tension-shear fracture mode. Fracture of the lower sheet sometimes occurs at high rotational speeds.

  8. Zone refining of sintered, microwave-derived YBCO superconductors

    International Nuclear Information System (INIS)

    Warrier, K.G.K.; Varma, H.K.; Mani, T.V.; Damodaran, A.D.; Balachandran, U.

    1993-07-01

    Post-sintering treatments such as zone melting under thermal gradient has been conducted on sintered YBCO tape cast films. YBCO precursor powder was derived through decomposition of a mixture of nitrates of cations in a microwave oven for ∼4 min. The resulting powder was characterized and made into thin sheets by tape casting and then sintered at 945 C for 5 h. The sintered tapes were subjected to repeated zone refining operations at relatively high speeds of ∼30 mm/h. A microstructure having uniformly oriented grains in the a-b plane throughout the bulk of the sample was obtained by three repeated zone refining operations. Details of precursor preparation, microwave processing and its advantages, zone refining conditions, and microstructural features are presented in this paper

  9. Modeling and experiment of shuttling speed effects on the OSTRYCH

    International Nuclear Information System (INIS)

    Chen, Jyh Jian; Yang, Yao Tsung

    2011-01-01

    A novel OScillatory TheRmal cYcler CHamber (OSTRYCH) has been designed and fabricated in our work. The sample is placed in a fixed chamber, and three constant isothermal zones are established and lined up in the system. The sample is oscillated and comes into contact with three different isothermal zones to complete thermal cycles. The commercial software CFD-ACE+ TM is utilized to investigate the influences of various chamber materials, boundary conditions and moving speeds of the chamber on the temperature distributions inside the chamber. The chamber moves at a specific speed and the boundary conditions with time variations are related to the moving speed. When the chamber moves, the boundary is specified at convection condition or the uniform temperature condition. The user subroutines coded and compiled by the FORTRAN language are introduced into the software to make the numerical results realistic. Results show that regarding the temperature profiles and the standard deviation of the temperature at the Y-cut cross section, the effects of various moving speeds of the chamber on the temperature distributions are negligible at the assigned time duration. The central temperatures of the chamber with various moving speeds are measured. The repeatability and stability of the OSTRYCH are examined. Finally, the experimental results and numerical simulations are compared and shown a similar trend. - Highlights: → Fabricate and test the performance of the OSTRYCH under various operational conditions. → Influences of various materials on the heat transfer. → Central temperatures of the chamber with various moving speeds. → Repeatability and stability of the OSTRYCH. → The experimental results and numerical simulations are shown a similar trend.

  10. REDUCTION IN CUTS SPEED AT THE BEGINNING OF A SORTING SIDINGS, EQUIPPED WITH QUASI-CONTINUOUS SPEED CONTROL SYSTEM

    Directory of Open Access Journals (Sweden)

    O. A. Nazarov

    2016-08-01

    Full Text Available Purpose. Clear and uninterrupted operation of humps depends on the quality of technical equipment and control technology of cuts speed. Technology of interval and purposive regulation of cuts speed is used at most humps. The article discusses ways to reduce the cuts rolling speed to a safe level at the beginning of the sorting sidings equipped with quasi-continuous speed control system. Methodology. It proposed three fundamentally different ways to reduce the cuts rolling speed at the beginning of the sorting siding. The analysis of the ways to reduce cuts rolling speed to a safe level at the beginning of the sorting sidings was conducted using simulation the process of cuts rolling from humps equipped with quasi-continuous speed control. Findings. As a result of analysis, the inappropriateness of opposite elevation using on the roll-out part of the hump after the last separation switch point. Spot regulators of cars speed can be used to reduce the cuts rolling speed at the beginning of the sorting siding, but this leads to a division conditions deterioration on the last separating switch points of long cuts with the following after them short cuts. Reducing the cuts rolling speed at the beginning of the sorting siding can be carried out using the beam on a stationary wagon retarders park brake position. Control Algorithm park brake position is quite simple. All produce should be unhooked from it at a safe speed. If the accuracy of the implementation of the set speed output to unhook from the park brake position is low, it is possible to eliminate the error of point regulators cars speed. Originality. The question where to start location point of wagon retarders zone to reduce speed to cut level requires additional research. Reducing rolling cut the speed at the beginning of the sorting sidings can be carried out using the beam on a stationary wagon retarders park brake position. Practical value. Control Algorithm park brake position is quite

  11. A probabilistic quantitative risk assessment model for the long-term work zone crashes.

    Science.gov (United States)

    Meng, Qiang; Weng, Jinxian; Qu, Xiaobo

    2010-11-01

    Work zones especially long-term work zones increase traffic conflicts and cause safety problems. Proper casualty risk assessment for a work zone is of importance for both traffic safety engineers and travelers. This paper develops a novel probabilistic quantitative risk assessment (QRA) model to evaluate the casualty risk combining frequency and consequence of all accident scenarios triggered by long-term work zone crashes. The casualty risk is measured by the individual risk and societal risk. The individual risk can be interpreted as the frequency of a driver/passenger being killed or injured, and the societal risk describes the relation between frequency and the number of casualties. The proposed probabilistic QRA model consists of the estimation of work zone crash frequency, an event tree and consequence estimation models. There are seven intermediate events--age (A), crash unit (CU), vehicle type (VT), alcohol (AL), light condition (LC), crash type (CT) and severity (S)--in the event tree. Since the estimated value of probability for some intermediate event may have large uncertainty, the uncertainty can thus be characterized by a random variable. The consequence estimation model takes into account the combination effects of speed and emergency medical service response time (ERT) on the consequence of work zone crash. Finally, a numerical example based on the Southeast Michigan work zone crash data is carried out. The numerical results show that there will be a 62% decrease of individual fatality risk and 44% reduction of individual injury risk if the mean travel speed is slowed down by 20%. In addition, there will be a 5% reduction of individual fatality risk and 0.05% reduction of individual injury risk if ERT is reduced by 20%. In other words, slowing down speed is more effective than reducing ERT in the casualty risk mitigation. 2010 Elsevier Ltd. All rights reserved.

  12. "Safe Zone" Classrooms: The Individual Student versus the Community

    Science.gov (United States)

    Kruk, Amber

    2013-01-01

    Independence Day School is a small college preparatory school serving grades 9-12, in rural Illinois. As part of its commitment to creating a safe school for all students, it adopted a "safe zone" classrooms policy. The policy states that classrooms where conversation about homosexuality is permitted are marked with inverted pink…

  13. Energy savings in sea bass swimming in a school: measurements of tail beat frequency and oxygen consumption at different swimming speeds

    DEFF Research Database (Denmark)

    Herskin, J; Steffensen, JF

    1998-01-01

    Tail beat frequency of sea bass, Dicentrarchus labrax (L.) (23.5 ± 0·5 cm, LT), swimming at the front of a school was significantly higher than when swimming at the rear, for all water velocities tested from 14·8 to 32 cm s-1. The logarithm of oxygen consumption rate, and the tail beat frequency...... of solitary swimming sea bass (28·8 ± 0·4 cm, LT), were each correlated linearly with swimming speed, and also with one another. The tail beat frequency of individual fish was 9-14% lower when at the rear of a school than when at the front, corresponding to a 9-23% reduction in oxygen consumption rate....

  14. Tool geometry, rotation and travel speeds effects on the properties of dissimilar magnesium/aluminum friction stir welded lap joints

    International Nuclear Information System (INIS)

    Mohammadi, J.; Behnamian, Y.; Mostafaei, A.; Gerlich, A.P.

    2015-01-01

    Highlights: • Tool geometry, rotation and travel speeds show great effect on the microstructure stability of FSW joint. • Increasing rotation and travel speeds resulted in increasing the tensile strength and ductility of the joints. • Better intermixing between Al/Mg alloys was obtained by tapered threaded pin. • A mechanical interlocking mechanism proposed for higher ductility and superior tensile properties in FSW joints. - Abstract: Lap joint friction stir welding (FSW) between dissimilar AZ31B and Al 6061 alloys sheets was conducted using various welding parameters including tool geometry, rotation and travel speeds. Tapered threaded pin and tapered pin tools were applied to fabricate FSW joints, using different rotation and travel speeds. Metallurgical investigations including X-ray diffraction pattern (XRD), optical microscopy images (OM), scanning electron microscopy equipped with an energy-dispersive X-ray spectroscopy (SEM–EDS) and electron probe microanalysis (EPMA) were used to characterize joints microstructures made with different welding parameters. Intermetallic phases were detected in the weld zone (WZ). Various microstructures were observed in the stir zone which can be attributed to using different travel and rotation speeds. Mechanical evaluation including lap shear fracture load test and microhardness measurements indicated that by simultaneously increasing the tool rotation and travel speeds, the joint tensile strength and ductility reached a maximum value. Microhardness studies and extracted results from stress–strain curves indicated that mechanical properties were affected by FSW process. Furthermore, phase analyses by XRD indicated the presence of intermetallic compounds in the weld zone. Finally, in the Al/Mg dissimilar weld, fractography studies showed that intermetallic compounds formation in the weld zone had an influence on the failure mode

  15. Trend on High-speed Power Line Communication Technology

    Science.gov (United States)

    Ogawa, Osamu

    High-speed power line communication (PLC) is useful technology to easily build the communication networks, because construction of new infrastructure is not necessary. In Europe and America, PLC has been used for broadband networks since the beginning of 21th century. In Japan, high-speed PLC was deregulated only indoor usage in 2006. Afterward it has been widely used for home area network, LAN in hotels and school buildings and so on. And recently, PLC is greatly concerned as communication technology for smart grid network. In this paper, the author surveys the high-speed PLC technology and its current status.

  16. School site walkability and active school transport - association, mediation and moderation

    DEFF Research Database (Denmark)

    Breum, Lars; Toftager, M.; Schipperijn, J.

    2014-01-01

    significantly moderated the association between the school walkability index and AST. This research confirms the association between the urban form surrounding schools and AST. Medium and highly walkable school sites in combination with a distance to school below 2. km, no speeding traffic and many paths...

  17. Theory of auroral zone PiB pulsation spectra

    International Nuclear Information System (INIS)

    Lysak, R.L.

    1988-01-01

    Changes in the auroral zone current system are often accompanied by magnetic pulsations with periods of about 1 s. These so-called bursts of irregular pulsations (PiB) have been observed both on ground magnetograms and with in situ satellite observations. These pulsations can be understood as excitations of a resonant cavity in the topside ionosphere, where the Alfven speed has a strong gradient due to the exponential decrease of density above the ionosphere. These waves have a frequency which scales as the ratio of the Alfven speed at the ionosphere divided by the ionospheric scale height. For a pure exponential Alfven speed profile, the mode frequencies are related to zeros of the zeroth-order Bessel function. For other profiles of the density, and therefore Alfven speed, the frequencies are not exactly given by the simple theory, but the frequency and mode structure are similar provided the Alfven speed sharply increases above the ionosphere

  18. Wind Speed Pattern in Nigeria (A Case Study of Some Coastal and ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Department of Physics and Solar Energy, Bowen University Iwo, Osun State, Nigeria ... ABSTRACT: In this study, wind speeds were analysed using the daily wind data obtained from Nigeria ..... Selected sites from Three Geopolitical Zones in.

  19. A method for processing the critical zone of a carbonate stratum

    Energy Technology Data Exchange (ETDEWEB)

    Dytyuk, L T; Barsukov, A V; Bragina, O A; Kalabina, A V; Samakayev, R Kh

    1982-01-01

    A method is proposed for processing the critical zone of a carbonate stratum by pumping a carbonate rock solvent into it. It is distinguished by the fact that in order to increase the penetration depth of the solvent into the stratum by reducing the speed of interaction of the solvent, a solution of beta-phenoxyvinylphosphonic acid is pumped into the critical zone of the stratum.

  20. Solar-cycle Variations of Meridional Flows in the Solar Convection Zone Using Helioseismic Methods

    Science.gov (United States)

    Lin, Chia-Hsien; Chou, Dean-Yi

    2018-06-01

    The solar meridional flow is an axisymmetric flow in solar meridional planes, extending through the convection zone. Here we study its solar-cycle variations in the convection zone using SOHO/MDI helioseismic data from 1996 to 2010, including two solar minima and one maximum. The travel-time difference between northward and southward acoustic waves is related to the meridional flow along the wave path. Applying the ray approximation and the SOLA inversion method to the travel-time difference measured in a previous study, we obtain the meridional flow distributions in 0.67 ≤ r ≤ 0.96R ⊙ at the minimum and maximum. At the minimum, the flow has a three-layer structure: poleward in the upper convection zone, equatorward in the middle convection zone, and poleward again in the lower convection zone. The flow speed is close to zero within the error bar near the base of the convection zone. The flow distribution changes significantly from the minimum to the maximum. The change above 0.9R ⊙ shows two phenomena: first, the poleward flow speed is reduced at the maximum; second, an additional convergent flow centered at the active latitudes is generated at the maximum. These two phenomena are consistent with the surface meridional flow reported in previous studies. The change in flow extends all the way down to the base of the convection zone, and the pattern of the change below 0.9R ⊙ is more complicated. However, it is clear that the active latitudes play a role in the flow change: the changes in flow speed below and above the active latitudes have opposite signs. This suggests that magnetic fields could be responsible for the flow change.

  1. Subduction factory 1. Theoretical mineralogy, densities, seismic wave speeds, and H2O contents

    Science.gov (United States)

    Hacker, Bradley R.; Abers, Geoffrey A.; Peacock, Simon M.

    2003-01-01

    We present a new compilation of physical properties of minerals relevant to subduction zones and new phase diagrams for mid-ocean ridge basalt, lherzolite, depleted lherzolite, harzburgite, and serpentinite. We use these data to calculate H2O content, density and seismic wave speeds of subduction zone rocks. These calculations provide a new basis for evaluating the subduction factory, including (1) the presence of hydrous phases and the distribution of H2O within a subduction zone; (2) the densification of the subducting slab and resultant effects on measured gravity and slab shape; and (3) the variations in seismic wave speeds resulting from thermal and metamorphic processes at depth. In considering specific examples, we find that for ocean basins worldwide the lower oceanic crust is partially hydrated (measurements. Subducted hydrous crust in cold slabs can persist to several gigapascals at seismic velocities that are several percent slower than the surrounding mantle. Seismic velocities and VP/VS ratios indicate that mantle wedges locally reach 60-80% hydration.

  2. Effect of welding speed on microstructural and mechanical properties of friction stir welded Inconel 600

    International Nuclear Information System (INIS)

    Song, K.H.; Fujii, H.; Nakata, K.

    2009-01-01

    In order to evaluate the properties of a friction stir welded Ni base alloy, Inconel 600 (single phase type) was selected. Sound friction stir welds without weld defect were obtained at 150 and 200 mm/min in welding speed, however, a groove like defect occurred at 250 mm/min. The electron back scattered diffraction (EBSD) method was used to analyze the grain boundary character distribution. As a result, dynamic recrystallization was observed at all conditions, and the grain refinement was achieved in the stir zone, and it was gradually accelerated from 19 μm in average grain size of the base material to 3.4 μm in the stir zone with increasing the welding speed. It also has an effect on the mechanical properties so that friction stir welded zone showed 20% higher microhardness and 10% higher tensile strength than those of base material.

  3. Computation of Acoustic Waves Through Sliding-Zone Interfaces Using an Euler/Navier-Stokes Code

    Science.gov (United States)

    Rumsey, Christopher L.

    1996-01-01

    The effect of a patched sliding-zone interface on the transmission of acoustic waves is examined for two- and three-dimensional model problems. A simple but general interpolation scheme at the patched boundary passes acoustic waves without distortion, provided that a sufficiently small time step is taken. A guideline is provided for the maximum permissible time step or zone speed that gives an acceptable error introduced by the sliding-zone interface.

  4. Computing moving and intermittent queue propagation in highway work zones.

    Science.gov (United States)

    2012-07-01

    Drivers may experience intermittent congestion and moving queue conditions in work zones due to several reasons such as presence of lane closure, roadway geometric changes, higher demand, lower speed, and reduced capacity. The congestion and queue ha...

  5. Effect of FSW welding speed on microstructure and microhardness of Al-0.84Mg-0.69Si-0.76Fe alloy at moderate rotational tool velocity

    Science.gov (United States)

    Chand, Suresh; Vineetha, S.; Madhusudhan, D.; Sai Krishna, CH; Kusuma Devi, G.; Bhawani; Hemarao, K.; Ganesh Naidu, G.

    2018-03-01

    The plate of 7.0 mm thickness was double side welded using friction stir welding is investigated. The rotational velocity of friction stir welding tool is used 1400 rpm. The influence of welding speed on the microstructure and microhardness values of Al-0.84Mg-0.69Si-0.76Fe aluminum alloy is presented. Two welding speeds 25 mm/min and 31.5 mm/min are used. The microhardness values of friction stir weld are measured at various locations from the weld interface. The microhardness values in stir zone of weld are found larger than lower welding speed at constant rotational velocity of 1400 rpm of friction stir welding tool. The similar effects on microhardness values are found in the thermo-mechanically affected zone and heat affected zone. The fine microstructure is observed at 31.5 mm/min welding speed compared to the 25 mm/min welding speed at 1400 rpm.

  6. Numerical study on wake characteristics of high-speed trains

    Science.gov (United States)

    Yao, Shuan-Bao; Sun, Zhen-Xu; Guo, Di-Long; Chen, Da-Wei; Yang, Guo-Wei

    2013-12-01

    Intensive turbulence exists in the wakes of high speed trains, and the aerodynamic performance of the trailing car could deteriorate rapidly due to complicated features of the vortices in the wake zone. As a result, the safety and amenity of high speed trains would face a great challenge. This paper considers mainly the mechanism of vortex formation and evolution in the train flow field. A real CRH2 model is studied, with a leading car, a middle car and a trailing car included. Different running speeds and cross wind conditions are considered, and the approaches of unsteady Reynold-averaged Navier-Stokes (URANS) and detached eddy simulation (DES) are utilized, respectively. Results reveal that DES has better capability of capturing small eddies compared to URANS. However, for large eddies, the effects of two approaches are almost the same. In conditions without cross winds, two large vortex streets stretch from the train nose and interact strongly with each other in the wake zone. With the reinforcement of the ground, a complicated wake vortex system generates and becomes strengthened as the running speed increases. However, the locations of flow separations on the train surface and the separation mechanism keep unchanged. In conditions with cross winds, three large vortices develop along the leeward side of the train, among which the weakest one has no obvious influence on the wake flow while the other two stretch to the tail of the train and combine with the helical vortices in the train wake. Thus, optimization of the aerodynamic performance of the trailing car should be aiming at reducing the intensity of the wake vortex system.

  7. Typing speed, spelling accuracy, and the use of word-prediction ...

    African Journals Online (AJOL)

    Children with spelling difficulties are limited in their participation in all written school activities. We aimed to investigate the influence of word-prediction as a tool on spelling accuracy and typing speed. To this end, we selected 80 Grade 4 – 6 children with spelling difficulties in a school for special needs to participate

  8. Demonstration of innovative techniques for work zone safety data analysis

    Science.gov (United States)

    2009-07-15

    Based upon the results of the simulator data analysis, additional future research can be : identified to validate the driving simulator in terms of similarities with Ohio work zones. For : instance, the speeds observed in the simulator were greater f...

  9. Improvement of automatic control system for high-speed current collectors

    Science.gov (United States)

    Sidorov, O. A.; Goryunov, V. N.; Golubkov, A. S.

    2018-01-01

    The article considers the ways of regulation of pantographs to provide quality and reliability of current collection at high speeds. To assess impact of regulation was proposed integral criterion of the quality of current collection, taking into account efficiency and reliability of operation of the pantograph. The study was carried out using mathematical model of interaction of pantograph and catenary system, allowing to assess contact force and intensity of arcing at the contact zone at different movement speeds. The simulation results allowed us to estimate the efficiency of different methods of regulation of pantographs and determine the best option.

  10. Bureaucratic accountability in the education action zones of South ...

    African Journals Online (AJOL)

    The Education Action Zone program me in Gauteng p rovince, South A frica, has been w idely seen as a very successful school improvement initiative, with particular significance as it represents a unique model of top-down, bureaucratic accountability as a vehicle for turning- around dysfunctional secondary schools. In this ...

  11. Aerobic capacity influences the spatial position of individuals within fish schools

    DEFF Research Database (Denmark)

    Killen, Shaun S.; Marras, Stefano; Steffensen, John Fleng

    2012-01-01

    the rear of schools. These trailing fish required fewer tail beats to swim at the same speed as individuals at the front of schools, indicating that posterior positions provide hydrodynamic benefits that reduce swimming costs. Conversely, fish with high aerobic capacity can withstand increased drag......The schooling behaviour of fish is of great biological importance, playing a crucial role in the foraging and predator avoidance of numerous species. The extent to which physiological performance traits affect the spatial positioning of individual fish within schools is completely unknown. Schools...... of juvenile mullet Liza aurata were filmed at three swim speeds in a swim tunnel, with one focal fish from each school then also measured for standard metabolic rate (SMR), maximal metabolic rate (MMR), aerobic scope (AS) and maximum aerobic swim speed. At faster speeds, fish with lower MMR and AS swam near...

  12. Two-zone elastic-plastic single shock waves in solids.

    Science.gov (United States)

    Zhakhovsky, Vasily V; Budzevich, Mikalai M; Inogamov, Nail A; Oleynik, Ivan I; White, Carter T

    2011-09-23

    By decoupling time and length scales in moving window molecular dynamics shock-wave simulations, a new regime of shock-wave propagation is uncovered characterized by a two-zone elastic-plastic shock-wave structure consisting of a leading elastic front followed by a plastic front, both moving with the same average speed and having a fixed net thickness that can extend to microns. The material in the elastic zone is in a metastable state that supports a pressure that can substantially exceed the critical pressure characteristic of the onset of the well-known split-elastic-plastic, two-wave propagation. The two-zone elastic-plastic wave is a general phenomenon observed in simulations of a broad class of crystalline materials and is within the reach of current experimental techniques.

  13. The use of high-speed imaging in education

    Science.gov (United States)

    Kleine, H.; McNamara, G.; Rayner, J.

    2017-02-01

    Recent improvements in camera technology and the associated improved access to high-speed camera equipment have made it possible to use high-speed imaging not only in a research environment but also specifically for educational purposes. This includes high-speed sequences that are created both with and for a target audience of students in high schools and universities. The primary goal is to engage students in scientific exploration by providing them with a tool that allows them to see and measure otherwise inaccessible phenomena. High-speed imaging has the potential to stimulate students' curiosity as the results are often surprising or may contradict initial assumptions. "Live" demonstrations in class or student- run experiments are highly suitable to have a profound influence on student learning. Another aspect is the production of high-speed images for demonstration purposes. While some of the approaches known from the application of high speed imaging in a research environment can simply be transferred, additional techniques must often be developed to make the results more easily accessible for the targeted audience. This paper describes a range of student-centered activities that can be undertaken which demonstrate how student engagement and learning can be enhanced through the use of high speed imaging using readily available technologies.

  14. Characteristics Analysis and Comparison of High-Speed 4/2 and Hybrid 4/4 Poles Switched Reluctance Motor

    Directory of Open Access Journals (Sweden)

    Grace Firsta Lukman

    2018-01-01

    Full Text Available This paper presents a characteristics analysis and performance comparison of high-speed two-phase 4/2 and hybrid single-phase 4/4 switched reluctance motors (SRMs. Although the motors are advantageous as high-speed drives, both conventional structures have high torque ripple as a result of the presence of the torque dead zone. In this paper, solutions to the torque dead zone problem for each motor are discussed. For the 4/2 SRM, a wide-rotor stepper-type is adopted, while for the 4/4 SRM, the structure is changed to a hybrid by adding permanent magnets (PMs. Both motors have a non-uniform air gap to modify their inductance profile, which leads to the elimination of the torque dead zone. A finite-element method was used to analyze the characteristics of each motor. Then, the manufactured motors were tested through experiments, and lastly, their performance was compared.

  15. The Level of Utilizing Blended Learning in Teaching Science from the Point of View of Science Teachers in Private Schools of Ajman Educational Zone

    Science.gov (United States)

    Al-Derbashi, Khaled Y.; Abed, Osama H.

    2017-01-01

    This study aims to define the level of utilizing blended learning in teaching science from the point of view of science teachers (85 male and female teachers) who are working in private schools of Ajman Educational Zone. The study also aims to find if there are significant differences according to gender, years of experience, or the fact that…

  16. The Effect of Premixed Al-Cu Powder on the Stir Zone in Friction Stir Welding of AA3003-H18

    Science.gov (United States)

    Abnar, B.; Kazeminezhad, M.; Kokabi, A. H.

    2015-02-01

    In this research, 3-mm-thick AA3003-H18 non-heat-treatable aluminum alloy plates were joined by friction stir welding (FSW). It was performed by adding pure Cu and premixed Cu-Al powders at various rotational speeds of 800, 1000, and 1200 rpm and constant traveling speeds of 100 mm/min. At first, the powder was filled into the gap (0.2 or 0.4 mm) between two aluminum alloy plates, and then the FSW process was performed in two passes. The microstructure, mechanical properties, and formation of intermetallic compounds were investigated in both cases of using pure Cu and premixed Al-Cu powders. The results of using pure Cu and premixed Al-Cu powders were compared in the stir zone at various rotational speeds. The copper particle distribution and formation of Al-Cu intermetallic compounds (Al2Cu and AlCu) in the stir zone were desirable using premixed Al-Cu powder into the gap. The hardness values were significantly increased by formation of Al-Cu intermetallic compounds in the stir zone and it was uniform throughout the stir zone when premixed Al-Cu powder was used. Also, longitudinal tensile strength from the stir zone was higher when premixed Al-Cu powder was used instead of pure Cu powder.

  17. Cellular Automata Models of Traffic Behavior in Presence of Speed Breaking Structures

    International Nuclear Information System (INIS)

    Ramachandran, Parthasarathy

    2009-01-01

    In this article, we study traffic flow in the presence of speed breaking structures. The speed breakers are typically used to reduce the local speed of vehicles near certain institutions such as schools and hospitals. Through a cellular automata model we study the impact of such structures on global traffic characteristics. The simulation results indicate that the presence of speed breakers could reduce the global flow under moderate global densities. However, under low and high global density traffic regime the presence of speed breakers does not have an impact on the global flow. Further the speed limit enforced by the speed breaker creates a phase distinction. For a given global density and slowdown probability, as the speed limit enforced by the speed breaker increases, the traffic moves from the reduced flow phase to maximum flow phase. This underlines the importance of proper design of these structures to avoid undesired flow restrictions. (general)

  18. Sleep-related vehicle crashes on low speed roads.

    Science.gov (United States)

    Filtness, A J; Armstrong, K A; Watson, A; Smith, S S

    2017-02-01

    Very little is known about the characteristics of sleep related (SR) crashes occurring on low speed roads compared with current understanding of the role of sleep in crashes occurring on high speed roads e.g. motorways. To address this gap, analyses were undertaken to identify the differences and similarities between (1) SR crashes occurring on roads with low (≤60km/h) and high (≥100km/h) speed limits, and (2) SR crashes and not-SR crashes occurring on roads with low speed limits. Police reports of all crashes occurring on low and high speed roads over a ten year period between 2000 and 2009 were examined for Queensland, Australia. Attending police officers identified all crash attributes, including 'fatigue/fell asleep', which indicates that the police believe the crash to have a causal factor relating to falling asleep, sleepiness due to sleep loss, time of day, or fatigue. Driver or rider involvement in crashes was classified as SR or not-SR. All crash-associated variables were compared using Chi-square tests (Cramer's V=effect size). A series of logistic regression was performed, with driver and crash characteristics as predictors of crash category. A conservative alpha level of 0.001 determined statistical significance. There were 440,855 drivers or riders involved in a crash during this time; 6923 (1.6%) were attributed as SR. SR crashes on low speed roads have similar characteristics to those on high speed roads with young (16-24y) males consistently over represented. SR crashes on low speed roads are noticeably different to not-SR crashes in the same speed zone in that male and young novice drivers are over represented and outcomes are more severe. Of all the SR crashes identified, 41% occurred on low speed roads. SR crashes are not confined to high speed roads. Low speed SR crashes warrant specific investigation because they occur in densely populated areas, exposing a greater number of people to risk and have more severe outcomes than not-SR crashes

  19. Speed Synchronization of Multi Induction Motors with Fuzzy Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    HACHEMI Glaoui

    2013-05-01

    Full Text Available A continuous web winding system is a large-scale, complex interconnected dynamic system with numerous tension zones to transport the web while processing it. There are two control schemes for large-scale system control: the centralized scheme and the decentralized scheme. Centralized control is the traditional control method, which considers all the information about the system to be a single dynamic model and design a control system for this model. Aspeed synchronization control strategy for multiple induction motors, based on adjacent cross-coupling control structure, is developed by employing total sliding mode control method. The proposed controlstrategy is to stabilize speed tracking of each induction motor while synchronizing its speed with the speed of the other motors so as to make speed synchronization error amongst induction motors converge to zero. The global stability and the convergence of the designedcontroller are proved by using Lyapunov method. Simulation results demonstrate the effectiveness of the proposed method.

  20. Increasing FSW join strength by optimizing feed rate, rotating speed and pin angle

    Science.gov (United States)

    Darmadi, Djarot B.; Purnowidodo, Anindito; Siswanto, Eko

    2017-10-01

    Principally the join in Friction Stir Welding (FSW) is formed due to mechanical bonding. At least there are two factors determines the quality of this join, first is the temperature in the area around the interface and secondly the intense of mixing forces in nugget zone to create the mechanical bonding. The adequate temperature creates good flowability of the nugget zone and an intensive mixing force produces homogeneous strong bonding. Based on those two factors in this research the effects of feed rate, rotating speed and pin angle of the FSW process to the tensile strength of resulted join are studied. The true experimental method was used. Feed rate was varied at 24, 42, 55 and 74 mm/minutes and from the experimental results, it can be concluded that the higher feed rate decreases the tensile strength of weld join and it is believed due to the lower heat embedded in the material. Inversely, the higher rotating speed increases the join’s tensile strength as a result of higher heat embedded in base metal and higher mixing force in the nugget zone. The rotating speed were 1842, 2257 and 2904 RPMs. The pin angle determines the direction of mixing force. With variation of pin angle: 0°, 4°, 8° and 12° the higher pin angle generally increases the tensile strength because of more intensive mixing force. For 12° pin angle the lower tensile strength is found since the force tends to push out the nugget area from the joint gap.

  1. Stagnant zone formation on diamond cutting tools during machining

    International Nuclear Information System (INIS)

    Izman, S.; Tamin, M.N.; Mon, T.T.; Venkatesh, V.C.; Shaharoun, A.M.

    2007-01-01

    Formation of an intact region on the rake face of cutting tool during machining is quite common phenomenon but its significance in maintaining tool edge sharpness has not been recognized by many researchers. This region is sometimes called stagnant zone. It is believed that when an intact zone present on the rake face, it delays the crater wear progress and hence maintaining the tool edge sharpness longer. This paper investigates the effect of edge radius, surface roughness of the rake face and cutting parameters on the formation of stagnant zone on two different type of diamond tools i.e. polycrystalline diamond PCD-KD100 and diamond-coated inserts when machining titanium alloy. The used inserta and post-processed chips were examined under FESEM and optical microscope after cutting at three different conditions. Experimental results show that the speed and feel, the tool edge radius, and the tool rake surface roughness significantly affect the stagnant zone formation. (author)

  2. How well does wind speed predict air-sea gas transfer in the sea ice zone? A synthesis of radon deficit profiles in the upper water column of the Arctic Ocean

    Science.gov (United States)

    Loose, B.; Kelly, R. P.; Bigdeli, A.; Williams, W.; Krishfield, R.; Rutgers van der Loeff, M.; Moran, S. B.

    2017-05-01

    We present 34 profiles of radon-deficit from the ice-ocean boundary layer of the Beaufort Sea. Including these 34, there are presently 58 published radon-deficit estimates of air-sea gas transfer velocity (k) in the Arctic Ocean; 52 of these estimates were derived from water covered by 10% sea ice or more. The average value of k collected since 2011 is 4.0 ± 1.2 m d-1. This exceeds the quadratic wind speed prediction of weighted kws = 2.85 m d-1 with mean-weighted wind speed of 6.4 m s-1. We show how ice cover changes the mixed-layer radon budget, and yields an "effective gas transfer velocity." We use these 58 estimates to statistically evaluate the suitability of a wind speed parameterization for k, when the ocean surface is ice covered. Whereas the six profiles taken from the open ocean indicate a statistically good fit to wind speed parameterizations, the same parameterizations could not reproduce k from the sea ice zone. We conclude that techniques for estimating k in the open ocean cannot be similarly applied to determine k in the presence of sea ice. The magnitude of k through gaps in the ice may reach high values as ice cover increases, possibly as a result of focused turbulence dissipation at openings in the free surface. These 58 profiles are presently the most complete set of estimates of k across seasons and variable ice cover; as dissolved tracer budgets they reflect air-sea gas exchange with no impact from air-ice gas exchange.

  3. Conflict resolution and alert zone estimation in air traffic management

    Science.gov (United States)

    Kuo, Vincent Hao-Hung

    The current air traffic control (ATC) system provides separations among all aircraft through pre-defined routes and flight procedures, and active controller participation. In particular, en route separations are achieved by choices of different flight routes, different flight levels, and speed control. During the final descent approach over an extended terminal area, aircraft separations are achieved by speed changes, altitude changes, and path stretching. Recently, a concept of free flight has been proposed for future air traffic management. In the proposed free flight environment, aircraft operators can change flight paths in real time, in order to achieve the best efficiency for the aircraft. Air traffic controllers are only supposed to intervene when situation warrants, to resolve potential conflicts among aircraft. In both cases, there is a region around each aircraft called alert zone. As soon as another aircraft touches the alert zone of own aircraft, either the own aircraft or both aircraft must initiate avoidance maneuvers to resolve a potential conflict. This thesis develops a systematic approach based on nonlinear optimal control theories to estimate alert zones in two aircraft conflict scenarios. Specifically, point-mass aircraft models are used to describe aircraft motions. Separate uses of heading, speed, and altitude control are first examined, and then the synergetic use of two control authorities are studied. Both cooperative maneuvers (in which both aircraft act) and non-cooperative maneuvers (in which the own aircraft acts alone) are considered. Optimal control problems are formulated to minimize the initial relative separation between the two aircraft for all possible initial conditions, subject to the requirement that inter-aircraft separation at any time satisfies the separation requirement. These nonlinear optimal control problems are solved numerically using a collation approach and the NPSOL software line for nonlinear programming. In

  4. Analysis of the heat affected zone in CO2 laser cutting of stainless steel

    Directory of Open Access Journals (Sweden)

    Madić Miloš J.

    2012-01-01

    Full Text Available This paper presents an investigation into the effect of the laser cutting parameters on the heat affected zone in CO2 laser cutting of AISI 304 stainless steel. The mathematical model for the heat affected zone was expressed as a function of the laser cutting parameters such as the laser power, cutting speed, assist gas pressure and focus position using the artificial neural network. To obtain experimental database for the artificial neural network training, laser cutting experiment was planned as per Taguchi’s L27 orthogonal array with three levels for each of the cutting parameter. Using the 27 experimental data sets, the artificial neural network was trained with gradient descent with momentum algorithm and the average absolute percentage error was 2.33%. The testing accuracy was then verified with 6 extra experimental data sets and the average predicting error was 6.46%. Statistically assessed as adequate, the artificial neural network model was then used to investigate the effect of the laser cutting parameters on the heat affected zone. To analyze the main and interaction effect of the laser cutting parameters on the heat affected zone, 2-D and 3-D plots were generated. The analysis revealed that the cutting speed had maximum influence on the heat affected zone followed by the laser power, focus position and assist gas pressure. Finally, using the Monte Carlo method the optimal laser cutting parameter values that minimize the heat affected zone were identified.

  5. Body size affects the strength of social interactions and spatial organization of a schooling fish (Pseudomugil signifer)

    Science.gov (United States)

    Romenskyy, Maksym; Herbert-Read, James E.; Ward, Ashley J. W.; Sumpter, David J. T.

    2017-04-01

    While a rich variety of self-propelled particle models propose to explain the collective motion of fish and other animals, rigorous statistical comparison between models and data remains a challenge. Plausible models should be flexible enough to capture changes in the collective behaviour of animal groups at their different developmental stages and group sizes. Here, we analyse the statistical properties of schooling fish (Pseudomugil signifer) through a combination of experiments and simulations. We make novel use of a Boltzmann inversion method, usually applied in molecular dynamics, to identify the effective potential of the mean force of fish interactions. Specifically, we show that larger fish have a larger repulsion zone, but stronger attraction, resulting in greater alignment in their collective motion. We model the collective dynamics of schools using a self-propelled particle model, modified to include varying particle speed and a local repulsion rule. We demonstrate that the statistical properties of the fish schools are reproduced by our model, thereby capturing a number of features of the behaviour and development of schooling fish.

  6. Surface topography and roughness of high-speed milled AlMn1Cu

    Science.gov (United States)

    Wang, Zhenhua; Yuan, Juntang; Yin, Zengbin; Hu, Xiaoqiu

    2016-10-01

    The aluminum alloy AlMn1Cu has been broadly applied for functional parts production because of its good properties. But few researches about the machining mechanism and the surface roughness were reported. The high-speed milling experiments are carried out in order to improve the machining quality and reveal the machining mechanism. The typical topography features of machined surface are observed by scan electron microscope(SEM). The results show that the milled surface topography is mainly characterized by the plastic shearing deformation surface and material piling zone. The material flows plastically along the end cutting edge of the flat-end milling tool and meanwhile is extruded by the end cutting edge, resulting in that materials partly adhere to the machined surface and form the material piling zone. As the depth of cut and the feed per tooth increase, the plastic flow of materials is strengthened and the machined surface becomes rougher. However, as the cutting speed increases, the plastic flow of materials is weakened and the milled surface becomes smoother. The cutting parameters (e.g. cutting speed, feed per tooth and depth of cut) influencing the surface roughness are analyzed. It can be concluded that the roughness of the machined surface formed by the end cutting edge is less than that by the cylindrical cutting edge when a cylindrical flat-end mill tool is used for milling. The proposed research provides the typical topography features of machined surface of the anti-rust aluminum alloy AlMn1Cu in high speed milling.

  7. A new procedure to measure children's reading speed and accuracy in Italian.

    Science.gov (United States)

    Morlini, Isabella; Stella, Giacomo; Scorza, Maristella

    2014-02-01

    Impaired readers in primary school should be early recognized, in order to asses a targeted intervention within the school and to start a teaching that respects the difficulties in learning to read, to write and to perform calculations. Screening procedures, inside the primary schools aimed at detecting children with difficulties in reading, are of fundamental importance for guaranteeing an early identification of dyslexic children and reducing both the primary negative effects--on learning--and the secondary negative effects--on the development of the personality--of this disturbance. In this study, we propose a new screening procedure measuring reading speed and accuracy. This procedure is very fast (it is exactly 1 min long), simple, cheap and can be provided by teachers without technical knowledge. On the contrary, most of the currently used diagnostic tests are about 10 min long and must be provided by experts. These two major flaws prevent the widespread use of these tests. On the basis of the results obtained in a survey on about 1500 students attending primary school in Italy, we investigate the relationships between variables used in the screening procedure and variables measuring speed and accuracy in the currently used diagnostic tests in Italy. Then, we analyse the validity of the screening procedure from a statistical point of view, and with an explorative factor analysis, we show that reading speed and accuracy seem to be two separate symptoms of the dyslexia phenomenon. Copyright © 2013 John Wiley & Sons, Ltd.

  8. High-Performance Schools: Affordable Green Design for K-12 Schools; Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Plympton, P.; Brown, J.; Stevens, K.

    2004-08-01

    Schools in the United States spend $7.8 billion on energy each year-more than the cost of computers and textbooks combined, according to a 2003 report from the National Center for Education Statistics. The U.S. Department of Energy (DOE) estimates that these high utility bills could be reduced as much as 25% if schools adopt readily available high performance design principles and technologies. Accordingly, hundreds of K-12 schools across the country have made a commitment to improve the learning and teaching environment of schools while saving money and energy and protecting the environment. DOE and its public- and private-sector partners have developed Energy Design Guidelines for High Performance Schools, customized for nine climate zones in U.S. states and territories. These design guidelines provide information for school decision makers and design professionals on the advantages of energy efficiency and renewable energy designs and technologies. With such features as natural day lighting, efficient electric lights, water conservation, and renewable energy, schools in all types of climates are proving that school buildings, and the students and teachers who occupy them, are indeed high performers. This paper describes high performance schools from each of the nine climate zones associated with the Energy Design Guidelines. The nine case studies focus on the high performance design strategies implemented in each school, as well as the cost savings and benefits realized by students, faculty, the community, and the environment.

  9. A numerical study of zone-melting process for the thermoelectric material of Bi2Te3

    Science.gov (United States)

    Chen, W. C.; Wu, Y. C.; Hwang, W. S.; Hsieh, H. L.; Huang, J. Y.; Huang, T. K.

    2015-06-01

    In this study, a numerical model has been established by employing a commercial software; ProCAST, to simulate the variation/distribution of temperature and the subsequent microstructure of Bi2Te3 fabricated by zone-melting technique. Then an experiment is conducted to measure the temperature variation/distribution during the zone-melting process to validate the numerical system. Also, the effects of processing parameters on crystallization microstructure such as moving speed and temperature of heater are numerically evaluated. In the experiment, the Bi2Te3 powder are filled into a 30mm diameter quartz cylinder and the heater is set to 800°C with a moving speed 12.5 mm/hr. A thermocouple is inserted in the Bi2Te3 powder to measure the temperature variation/distribution of the zone-melting process. The temperature variation/distribution measured by experiment is compared to the results of numerical simulation. The results show that our model and the experiment are well matched. Then the model is used to evaluate the crystal formation for Bi2Te3 with a 30mm diameter process. It's found that when the moving speed is slower than 17.5 mm/hr, columnar crystal is obtained. In the end, we use this model to predict the crystal formation of zone-melting process for Bi2Te3 with a 45 mm diameter. The results show that it is difficult to grow columnar crystal when the diameter comes to 45mm.

  10. Effectiveness of Motorcycle speed controlled by speed hump

    Directory of Open Access Journals (Sweden)

    Pornsiri Urapa

    2014-09-01

    Full Text Available Speed humps are one of the traffic calming measures widely accepted to control vehicle speed in the local road. Humps standards from the western countries are designed mainly for the passenger car. This study, therefore, aims to reveal the effectiveness of speed hump to control the motorcycle speed. This study observes the free-flow speed of the riders at the total of 20 speed bumps and humps. They are 0.3-14.8 meter in width and 5-18 centimeter in height. The results reveal that the 85th percentile speeds reduce 15-65 percent when crossing the speed bumps and speed humps. Besides, this study develops the speed model to predict the motorcycle mean speed and 85th percentile speed. It is found that speed humps follow the ITE standard can control motorcycle crossing speeds to be 25-30 Kph which are suitable to travel on the local road.

  11. Effect of Welding Speed on Microstructure and Mechanical Properties due to The Deposition of Reinforcements on Friction Stir Welded Dissimilar Aluminium Alloys

    Directory of Open Access Journals (Sweden)

    Baridula Ravinder Reddy

    2017-01-01

    Full Text Available The strength of the welded joint obtained by solid state stir welding process was found to be improved as compared to fusion welding process. The deposition of reinforcements during friction stir welding process can further enhance the strength of the welded joint by locking the movement of grain boundaries. In the present study, the aluminium alloys AA2024 and AA7075 were welded effectively by depositing the multi-walled carbon nanotubes in to the stir zone. The mechanical properties and microstructures were studied by varying the traverse speed at constant rotational speed. The results show that rotating tool pin stirring action and heat input play an important role in controlling the grain size. The carbon nanotubes were found to be distributed uniformly at a welding speed (traverse speed of 80mm/min. This enhanced the mechanical properties of the welded joint. The microstructure and Electron dispersive X-ray analysis (EDX studies indicate that the deposition of carbon nanotubes in the stir zone was influenced by the traverse speed.

  12. 76 FR 26931 - Safety Zone; Second Annual Space Coast Super Boat Grand Prix, Atlantic Ocean, Cocoa Beach, FL

    Science.gov (United States)

    2011-05-10

    ...-AA00 Safety Zone; Second Annual Space Coast Super Boat Grand Prix, Atlantic Ocean, Cocoa Beach, FL... temporary safety zone on the waters of the Atlantic Ocean east of Cocoa Beach, Florida during the Second... Atlantic Ocean east of Cocoa Beach, Florida. Approximately 30 high-speed power boats will be participating...

  13. Using road markings as a continuous cue for speed choice.

    Science.gov (United States)

    Charlton, Samuel G; Starkey, Nicola J; Malhotra, Neha

    2018-08-01

    The potential for using road markings to indicate speed limits was investigated in a driving simulator over the course of two sessions. Two types of experimental road markings, an "Attentional" set designed to provide visually distinct cues to indicate speed limits of 60, 80 and 100 km/h, and a "Perceptual" set designed to also affect drivers' perception of speed, were compared to a standard undifferentiated set of markings. Participants (n = 20 per group) were assigned to one of four experimental groups (Attentional-Explicit, Attentional-Implicit, Perceptual-Explicit, Perceptual-Implicit) or a Control group (n = 22; standard road markings). The Explicit groups were instructed about the meaning of the road markings while those in the Implicit and Control groups did not receive any explanation. Participants drove five 10 km simulated roads containing three speed zones (60, 80 and 100 km/h) during the first session. The participants returned to the laboratory approximately 3 days later to drive five more trials including roads they had not seen before, a trial that included a secondary task, and a trial where speed signs were removed and only markings were present. The findings indicated that both types of road markings improved drivers' compliance with speed limits compared to the control group, but that explicit instruction as to the meaning of the markings was needed to realise their full benefit. Although previous research has indicated the benefit of road markings used as warnings to indicate speed reductions in advance of horizontal or vertical curves, the findings of the present experiment also suggest that systematically associating road markings with specific speed limits may be a useful way to improve speed limit compliance and increase speed homogeneity. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. GENERATION OF A TYPICAL METEOROLOGICAL YEAR FOR PORT HARCOURT ZONE

    Directory of Open Access Journals (Sweden)

    OGOLOMA O.B.

    2011-04-01

    Full Text Available This paper presents data for the typical meteorological year (TMY for the Port Harcourt climatic zone based on the hourly meteorological data recorded during the period 1983–2002, using the Finkelstein-Schafer statistical method. The data are the global solar radiation, wind velocity, dry bulb temperature, relative humidity, and others. The HVAC outside design conditions for the Port Harcourt climatic zone (latitude 4.44oN, longitude 7.1oE, elevation 20 m were found to be 26.7oC, 78.6% and 3.5 m/s for the dry bulb temperature, relative humidity and wind speed, respectively, and 13.5 MJ/m2/day for the global solar radiation. The TMY data for the zone are shown to be sufficiently reliable for engineering practice.

  15. In the Zone--Bringing Science to the Olympic Games for Students in 2012

    Science.gov (United States)

    Holmes, Leah; Atkinson, Melissa; Schofield, Jonathan

    2012-01-01

    The Wellcome Trust is running a national engagement and education initiative inspired by the London 2012 Olympic and Paralympic Games. "In the Zone" involves sending practical science kits to every UK school and college. Here, we discuss the development of the school activities and how the feedback from pilot schools helped to shape the…

  16. Substance use and associated factors among preparatory school students in Bale Zone, Oromia Regional State, Southeast Ethiopia.

    Science.gov (United States)

    Dida, Nagasa; Kassa, Yibeltal; Sirak, Teshome; Zerga, Ephrem; Dessalegn, Tariku

    2014-08-09

    The use of cigarettes, alcohol, khat, and other substances is a worldwide threat which especially affects young people and which is also common among the youth of Ethiopia. However, its prevalence and associated factors have not been addressed well yet. Thus, this study aimed to assess the prevalence and associated factors of substance use among preparatory school students in Bale Zone, Oromia Regional State, Southeast Ethiopia. An institutional-based cross-sectional study was conducted among 603 randomly selected students from five of eight preparatory schools of Bale Zone, Oromia Regional State, Southeast Ethiopia, in March 2013. The sample size was calculated by a single population proportion formula and allocated proportionally for the schools based on the number of students. A pretested structured questionnaire was used to collect the data. The data were analyzed using SPSS version 16.0. Descriptive, bivariate, and multivariate logistic regressions were employed to identify the predictors of substance use. The overall current prevalence of substance use among the respondents was 34.8% (210). Specifically, 23.6% (102) and 4.6% (28) of the respondents chewed khat and smoked cigarette, respectively. Sex, age, and substance use status of the respondents' father, mother, siblings, and best friend had an association with substance use. Male respondents were about ten times more at risk of practicing substance use compared to female respondents [adjusted odds ratio (AOR) 11.37, 95% confidence interval (CI) 4.42-29.23]. Respondents whose sibling(s) smokes cigarette were four times more likely to use substance (AOR 4.44, 95% CI 1.11-17.79). Respondents whose best friend chews khat were 11 times more likely to use substance when compared with those whose best friend does not practice the given factor (AOR 11.15, 95% CI 4.43-28.07). Respondents whose family uses one or more substances were more likely use substance(s). Respondents whose best friend uses substance(s) were

  17. Spectacles May Improve Reading Speed in Children with Hyperopia

    NARCIS (Netherlands)

    van Rijn, L.J.; Krijnen, J.S.M.; Nefkens-Molster, A.E.; Wensing, K.; Gutker, E.; Knol, D.L.

    2014-01-01

    PURPOSE: The purpose of this study was to investigate the role of (hyperopic or myopic) spectacle correction in reading speed of 9- to 10-year-old children. Methods: Subjects were recruited at their schools. Initial selection was based on reduced distance acuity and/or a positive blur test. Final

  18. Risky sexual behaviors and associated factors among male and female students in Jimma Zone preparatory schools, South West Ethiopia: comparative study.

    Science.gov (United States)

    Fentahun, Netsanet; Mamo, Abebe

    2014-01-01

    Youth engage in risk sexual behavior due to insufficient knowledge of reproductive health and family planning. Youth sexual behavior is important not only because of the possible reproductive outcomes, but also because of sexually transmitted infections. The level of risks and sexual behaviors are different between male and female youth due to sexual exposure and socio-cultural factors. The aim of this study was to compare risky sexual behaviors and associated factors among male and female preparatory school (grades 11 and 12) students in Jimma Zone. A comparative cross-sectional study was conducted in 5 randomly selected preparatory schools of Jimma Zone. A total of 520 students were selected using simple random sampling technique. A structured, pretested and self-administered questionnaire was used to collect data. Both descriptive analysis and binary logistic regressions were performed on the data to understand risky sexual behaviors among students. Twenty-two (25.9%) of male and 25(21.6%) of female students had two or more sexual partners in the last six months. Eighty-three (32.3%), 113(43.5%) male and female students were sexually at risk in the last six months. Only 8(9.4%) of the male and 10(8.6%) of the female students used condom consistently in the last six months. Female students living away from their parents were 3 times more likely to be at risk than students living with their parents (OR 95%CI 3.0(1.48-6.34)). Female students who consumed alcohol were 7 times more likely to be at risk than those who did not consume alcohol (OR 95%CI 7.27(3.36-15.7)). Male students who consumed alcohol were 2.8 times more likely to be at risk than those who did not consumed alcohol (OR 95%CI, 2.81(1.3-6.06)). Male students who chewed khat were 4.6 times more likely to be at risk than students who did not chew khat (OR 95%CI, 4.58(1.95-10.76). Living arrangement, educational status of parents, family connectedness, alcohol consumption and khat-chewing were the major

  19. Seismic Measurement of the Locations of the Base of Convection Zone and Helium Ionization Zone for Stars in the Kepler Seismic LEGACY Sample

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Kuldeep; Lund, Mikkel N.; Aguirre, Víctor Silva [Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Raodeo, Keyuri; Mazumdar, Anwesh [Homi Bhabha Centre for Science Education, TIFR, V. N. Purav Marg, Mankhurd, Mumbai 400088 (India); Antia, H. M. [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Basu, Sarbani, E-mail: kuldeep@phys.au.dk [Astronomy Department, Yale University, P.O. Box 208101, New Haven, CT 065208101 (United States)

    2017-03-01

    Acoustic glitches are regions inside a star where the sound speed or its derivatives change abruptly. These leave a small characteristic oscillatory signature in the stellar oscillation frequencies. With the precision achieved by Kepler seismic data, it is now possible to extract these small amplitude oscillatory signatures, and infer the locations of the glitches. We perform glitch analysis for all the 66 stars in the Kepler seismic LEGACY sample to derive the locations of the base of the envelope convection zone (CZ) and the helium ionization zone. The signature from helium ionization zone is found to be robust for all stars in the sample, whereas the CZ signature is found to be weak and problematic, particularly for relatively massive stars with large errorbars on the oscillation frequencies. We demonstrate that the helium glitch signature can be used to constrain the properties of the helium ionization layers and the helium abundance.

  20. A numerical study of zone-melting process for the thermoelectric material of Bi2Te3

    International Nuclear Information System (INIS)

    Chen, W C; Wu, Y C; Hwang, W S; Hsieh, H L; Huang, J Y; Huang, T K

    2015-01-01

    In this study, a numerical model has been established by employing a commercial software; ProCAST, to simulate the variation/distribution of temperature and the subsequent microstructure of Bi 2 Te 3 fabricated by zone-melting technique. Then an experiment is conducted to measure the temperature variation/distribution during the zone-melting process to validate the numerical system. Also, the effects of processing parameters on crystallization microstructure such as moving speed and temperature of heater are numerically evaluated. In the experiment, the Bi 2 Te 3 powder are filled into a 30mm diameter quartz cylinder and the heater is set to 800°C with a moving speed 12.5 mm/hr. A thermocouple is inserted in the Bi 2 Te 3 powder to measure the temperature variation/distribution of the zone-melting process. The temperature variation/distribution measured by experiment is compared to the results of numerical simulation. The results show that our model and the experiment are well matched. Then the model is used to evaluate the crystal formation for Bi 2 Te 3 with a 30mm diameter process. It's found that when the moving speed is slower than 17.5 mm/hr, columnar crystal is obtained. In the end, we use this model to predict the crystal formation of zone-melting process for Bi 2 Te 3 with a 45 mm diameter. The results show that it is difficult to grow columnar crystal when the diameter comes to 45mm. (paper)

  1. Effect of friction stir welding speed on the microstructure and mechanical properties of a duplex stainless steel

    International Nuclear Information System (INIS)

    Saeid, T.; Abdollah-zadeh, A.; Assadi, H.; Malek Ghaini, F.

    2008-01-01

    The present study focuses on the effect of the welding speed on the microstructure and mechanical properties of the stir zone (SZ) in friction stir welding (FSW) of SAF 2205 duplex stainless steel. A single tool, made of a WC-base material, was used to weld 2 mm-thick plates at a constant rotational speed of 600 rpm. X-ray radiography revealed that sound welds were successfully obtained for the welding speeds in the range of 50-200 mm/min, whereas a groove-like defect was formed at the higher speed of 250 mm/min. Moreover, increasing the welding speed decreased the size of the α and γ grains in the SZ, and hence, improved the mean hardness value and the tensile strength of the SZ. These results are interpreted with respect to interplay between the welding speed and the peak temperature in FSW

  2. Prevalence of refractive error and visual impairment among rural school-age children of Goro District, Gurage Zone, Ethiopia.

    Science.gov (United States)

    Kedir, Jafer; Girma, Abonesh

    2014-10-01

    Refractive error is one of the major causes of blindness and visual impairment in children; but community based studies are scarce especially in rural parts of Ethiopia. So, this study aims to assess the prevalence of refractive error and its magnitude as a cause of visual impairment among school-age children of rural community. This community-based cross-sectional descriptive study was conducted from March 1 to April 30, 2009 in rural villages of Goro district of Gurage Zone, found south west of Addis Ababa, the capital of Ethiopia. A multistage cluster sampling method was used with simple random selection of representative villages in the district. Chi-Square and t-tests were used in the data analysis. A total of 570 school-age children (age 7-15) were evaluated, 54% boys and 46% girls. The prevalence of refractive error was 3.5% (myopia 2.6% and hyperopia 0.9%). Refractive error was the major cause of visual impairment accounting for 54% of all causes in the study group. No child was found wearing corrective spectacles during the study period. Refractive error was the commonest cause of visual impairment in children of the district, but no measures were taken to reduce the burden in the community. So, large scale community level screening for refractive error should be conducted and integrated with regular school eye screening programs. Effective strategies need to be devised to provide low cost corrective spectacles in the rural community.

  3. Fine Tuning the CJ Detonation Speed of a High Explosive products Equation of State

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-05-12

    For high explosive (HE) simulations, inaccuracies of a per cent or two in the detonation wave speed can result from not suficiently resolving the reaction zone width or from small inaccuracies in calibrating the products equation of state (EOS) or from variation of HE lots. More accurate detonation speeds can be obtained by ne tuning the equation of state to compensate. Here we show that two simple EOS transformations can be used to adjust the CJ detonation speed by a couple of per cent with minimal effect on the CJ release isentrope. The two transformations are (1) a shift in the energy origin and (2) a linear scaling of the speci c volume. The effectiveness of the transformations is demonstrated with simulations of the cylinder test for PBX 9502 starting with a products EOS for which the CJ detonation speed is 1 per cent too low.

  4. A parametric investigation of hydrogen hcci combustion using a multi-zone model approach

    International Nuclear Information System (INIS)

    Komninos, N.P.; Hountalas, D.T.; Rakopoulos, C.D.

    2007-01-01

    The purpose of the present study is to examine the effect of various operating variables of a homogeneous charge compression ignition (HCCI) engine fueled with hydrogen, using a multi-zone model developed by the authors. The multi-zone model consists of zones, which are allotted spatial locations within the combustion chamber. The model takes into account heat transfer between the zones and the combustion chamber walls, providing a spatial temperature distribution during the closed part of the engine cycle, i.e. compression, combustion and expansion. Mass transfer between zones is also accounted for, based on the geometric configuration of the zones, and includes the flow of mass in and out of the crevice regions, represented by the crevice zone. Combustion is incorporated using chemical kinetics based on a chemical reaction mechanism for the oxidation of hydrogen. This chemical reaction mechanism also includes the reactions for nitrogen oxides formation. Using the multi-zone model a parametric investigation is conducted, in order to determine the effect of engine speed, equivalence ratio, compression ratio, inlet pressure and inlet temperature, on the performance, combustion characteristics and emissions of an HCCI engine fueled with hydrogen

  5. Microphysical characteristics of squall-line stratiform precipitation and transition zones inferred using an ice particle property-evolving model

    Science.gov (United States)

    Jensen, A. A.; Harrington, J. Y.; Morrison, H.

    2017-12-01

    A quasi-idealized 3D squall line (based on a June 2007 Oklahoma case) is simulated using a novel bulk microphysics scheme called the Ice-Spheroids Habit Model with Aspect-ratio Evolution (ISHMAEL). In ISHMAEL, the evolution of ice particle properties, such as mass, shape, maximum diameter, density, and fall speed, are tracked as these properties evolve from vapor growth, sublimation, riming, and melting. Thus, ice properties evolve from various microphysical processes without needing separate unrimed and rimed ice categories. Simulation results show that ISHMAEL produces both a squall-line transition zone and an enhanced stratiform precipitation region. The ice particle properties produced in this simulation are analyzed and compared to observations to determine the characteristics of ice that lead to the development of these squall-line features. It is shown that rimed particles advected rearward from the convective region produce the enhanced stratiform precipitation region. The development of the transition zone results from hydrometer sorting: the evolution of ice particle properties in the convective region produces specific fall speeds that favor significant ice advecting rearward of the transition zone before reaching the melting level, causing a local minimum in precipitation rate and reflectivity there. Microphysical sensitivity studies, for example turning rime splintering off, that lead to changes in ice particle properties reveal that the fall speed of ice particles largely determines both the location of the enhanced stratiform precipitation region and whether or not a transition zone forms.

  6. Safe Speeds and Credible Speed Limits (SaCredSpeed): New Vision for Decision Making on Speed Management.

    NARCIS (Netherlands)

    Aarts, L. Nes, N. van Wegman, F.C.M. Schagen, I.N.L.G. van & Louwerse, R.

    2009-01-01

    Speed is an inherent characteristic of mobility and a hazard to safety. Several approaches exist of how to manage speed. In the Netherlands, the emphasis has mainly been on harm minimisation during the last decades, due to the implementation of the Sustainable Safety vision. Speed management remains

  7. 4-Meter Gait Speed Test in Chronic Obstructive Pulmonary Disease: INTERRATER RELIABILITY USING A STOPWATCH.

    Science.gov (United States)

    Bisca, Gianna Waldrich; Fava, Lucas Rodrigues; Morita, Andrea Akemi; Machado, Felipe Vilaça Cavallari; Pitta, Fabio; Hernandes, Nidia Aparecida

    2017-12-14

    4-meter gait speed (4MGS) is increasingly used to assess functional performance in patients with chronic obstructive pulmonary disease. However, the current literature lacks information regarding some technical standards for this test. Therefore, the purpose of this study was to compare and to evaluate the interrater reliability between a stopwatch and video recording used as timing systems for the 4MGS in patients with chronic obstructive pulmonary disease, as well as to verify the interrater reliability between 2 observers measuring the 4MGS time using a manual stopwatch. Fifty-one patients performed the 4MGS using 4 different protocols (random order): walking at the usual and maximum speed in a 4-meter course and walking at the same 2 speeds on an 8-m course using a 2-m acceleration zone, a 4-meter timing area, and a 2-m deceleration zone. Gait speed was measured simultaneously using a stopwatch and a video recording. In a subanalysis (n = 24), 2 independent observers timed the 4MGS using a stopwatch. There was no significant difference in comparison between the 2 timing methods (P > .05 for all), and the reliability between video recording and stopwatch was excellent in all 4MGS studied protocols (intraclass correlation coefficient ≥ 0.91). Moreover, when comparing gait speed measured by 2 observers using a stopwatch, no significant difference was found among all proposed protocols (P > .05 for all), and there was also excellent reliability between the 2 independent observers (intraclass correlation coefficient ≥ 0.94). The stopwatch, a low-cost and feasible tool, is reliable as a timing device for the 4MGS in patients with chronic obstructive pulmonary disease.

  8. Comprehensive surface treatment of high-speed steel tool

    Science.gov (United States)

    Fedorov, Sergey V.; Aleshin, Sergey V.; Swe, Min Htet; Abdirova, Raushan D.; Kapitanov, Alexey V.; Egorov, Sergey B.

    2018-03-01

    One of the promising directions of hardening of high-speed steel tool is the creation on their surface of the layered structures with the gradient of physic-chemical properties between the wear-resistant coatings to the base material. Among the methods of such surface modification, a special process takes place based on the use of pulsed high-intensity charged particle beams. The high speed of heating and cooling allows structural-phase transformations in the surface layer, which cannot be realized in a stationary mode. The treatment was conducted in a RITM-SP unit, which constitutes a combination of a source of low-energy high-current electron beams "RITM" and two magnetron spraying systems on a single vacuum chamber. The unit enables deposition of films on the surface of the desired product and subsequent liquid-phase mixing of materials of the film and the substrate by an intense pulse electron beam. The article discusses features of the structure of the subsurface layer of high-speed steel M2, modified by surface alloying of a low-energy high-current electron beam, and its effect on the wear resistance of the tool when dry cutting hard to machine Nickel alloy. A significant decrease of intensity of wear of high-speed steel with combined treatment happens due to the displacement of the zone of wear and decrease the radius of rounding of the cutting edge because of changes in conditions of interaction with the material being treated.

  9. MOTORIC SPEED AND MANUAL DEXTERITY OF CHILDERN WITH IMPAIRED VISION

    Directory of Open Access Journals (Sweden)

    Dženana Radžo Alibegović

    2017-04-01

    Full Text Available The aim of this study was to estimate the motoric speed and manual dexterity of children with visual impairments. The research is covered by a sample size of 35 participants with visual impairment, with ages between 7 and 15 years, of which 19 participants with visual impairment were male and 16 participants with impaired vision were female. The study was conducted in 17 primary schools in the municipality of Tuzla, Bosnia and Herzegovina. The results showed that the motoric speed and manual dexterity of children with visual impairment is evenly developed on the right and left hand, and also on both hands together and that there is a relationship between the motoric speed and manual dexterity of the right and left hand and both hands together.

  10. The effects of casting speed on steel continuous casting process

    Energy Technology Data Exchange (ETDEWEB)

    Sadat, Mohammad; Honarvar Gheysari, Ali; Sadat, Saeid [Islamic Azad University, Department of Mechanics, Mashhad Branch, Mashhad (Iran, Islamic Republic of)

    2011-12-15

    A three dimensional simulation of molten steel flow, heat transfer and solidification in mold and ''secondary cooling zone'' of Continuous Casting machine was performed with consideration of standard k-{epsilon} model. For this purpose, computational fluid dynamics software, FLUENT was utilized. From the simulation standpoint, the main distinction between this work and preceding ones is that, the phase change process (solidification) and flow (turbulent in mold section and laminar in secondary cooling zone) have been coupled and solved jointly instead of dividing it into ''transient heat conduction'' and ''steady fluid flow'' that can lead to more realistic simulation. Determining the appropriate boundary conditions in secondary cooling zone is very complicated because of various forms of heat transfer involved, including natural and forced convection and simultaneous radiation heat transfer. The main objective of this work is to have better understanding of heat transfer and solidification in the continuous casting process. Also, effects of casting speed on heat flux and shell thickness and role of radiation in total heat transfer is discussed. (orig.)

  11. UNDESIRED SPLASH OVER ON EQUIPMENTS USING INDUCTIVE SENSORS FOR MONITORING AUTOMOTIVE VEHICLES' CONTROLLED SPEED

    Directory of Open Access Journals (Sweden)

    Silvio Monteiro

    Full Text Available This article aims to evaluate instruments that oversight traffic flow electronically, using inductive surface sensors, based on the change of local magnetic field. More specifically, we study the possibility of false speed detections, due to the manifestation of the phenomenon called splash over - which means a space splash of the magnetic field lines out of the measuring zone. We show, through the literature, and practical simulations, the damage that can be caused by splash on the correct speed measurement and identification of the car under suspicions. It is also presented solutions to inhibiting unwanted velocity measurements due to this effect.

  12. Improving speed behaviour : the potential of in-car speed assistance and speed limit credibility.

    NARCIS (Netherlands)

    Nes, C.N. van Houtenbos, M. & Schagen, I.N.L.G. van

    2009-01-01

    Speeding is still a common practice on many roads and it contributes to a significant number of crashes. Two new approaches to solve speeding issues are focused on: intelligent speed assistance systems (ISA) and speed limit credibility. Research has indicated that ISA is promising with respect to

  13. Comparison between OpenFOAM CFD & BEM theory for variable speed – variable pitch HAWT

    Directory of Open Access Journals (Sweden)

    ElQatary Islam

    2014-01-01

    Full Text Available OpenFoam is used to compare computational fluid dynamics (CFD with blade element momentum theory (BEM for a variable speed - variable pitch HAWT (Horizontal Axis Wind Turbine. The wind turbine is first designed using the BEM to determine the blade chord, twist and operating conditions. The wind turbine blade has an outer diameter of 14 m, uses a NACA 63–415 profile for the entire blade and root to tip twist distribution of 15deg (Figure 3. The RPM varies from 20–75 for freestream velocities varying between 3–10.5 m/s (variable speed and a constant RPM of 78.78 for velocities ranging between 11–25 m/s (variable pitch. OpenFOAM is used to investigate the wind turbine performance at several operating points including cut-in wind speed (3 m/s, rated wind speed (10.5 m/s and in the variable pitch zone. Simulation results show that in the variable-speed operating range, both CFD and BEM compare reasonably well. This agreement can be attributed to the fact that the complex three-dimensional flow around the turbine blades can be split into two radial segments. For radii less than the mid-span, the flow is three-dimensional, whereas for radii greater than the mid-span, the flow is approximately two-dimensional. Since the majority of the power is produced from sections beyond the mid-span, the agreement between CFD and BEM is reasonable. For the variable-pitch operating range the CFD results and BEM deviate considerably. In this case the majority of the power is produced from the inner sections in which the flow is three-dimensional and can no longer be predicted by the BEM. The results show that differences in pitch angles up to 10deg can result to regulate the power for high wind speeds in the variable-pitch operation zone.

  14. Idle reduction programs and potential benefits to schools

    Science.gov (United States)

    2010-11-01

    School districts in Texas and many other states have, in recent years, increased the walk zones : surrounding schools to a 2-mile perimeter. Inside this perimeter, either no school bus service is : offered, or service is offered only with a fee...

  15. Speed

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Speed. The rate of information transferred per second is the speed of the information. Measured in bits per second. Need for speed on the net: You-Tube phenomenon; IPTV; 3D Video telephony. Online gaming; HDTV.

  16. Speed control at low wind speeds for a variable speed fixed pitch wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Rosmin, N.; Watson, S.J.; Tompson, M. [Loughborough Univ., Loughborough, Leicestershire (United Kingdom)

    2010-03-09

    The maximum power regulation below rated wind speed is regulated by changing the rotor/generator speed at large frequency range in a fixed pitch, variable speed, stall-regulated wind turbine. In order to capture the power at a maximum value the power coefficient is kept at maximum peak point by maintaining the tip speed ratio at its optimum value. The wind industry is moving from stall regulated fixed speed wind turbines to newer improved innovative versions with better reliability. While a stall regulated fixed pitch wind turbine is among the most cost-effective wind turbine on the market, its problems include noise, severe vibrations, high thrust loads and low power efficiency. Therefore, in order to improve such drawbacks, the rotation of the generator speed is made flexible where the rotation can be controlled in variable speed. This paper discussed the development of a simulation model which represented the behaviour of a stall regulated variable speed wind turbine at low wind speed control region by using the closed loop scalar control with adjustable speed drive. The paper provided a description of each sub-model in the wind turbine system and described the scalar control of the induction machine. It was concluded that by using a constant voltage/frequency ratio of the generator's stator side control, the generator speed could be regulated and the generator torque could be controlled to ensure the power coefficient could be maintained close to its maximum value. 38 refs., 1 tab., 10 figs.

  17. Speed, speed variation and crash relationships for urban arterials.

    Science.gov (United States)

    Wang, Xuesong; Zhou, Qingya; Quddus, Mohammed; Fan, Tianxiang; Fang, Shou'en

    2018-04-01

    Speed and speed variation are closely associated with traffic safety. There is, however, a dearth of research on this subject for the case of urban arterials in general, and in the context of developing nations. In downtown Shanghai, the traffic conditions in each direction are very different by time of day, and speed characteristics during peak hours are also greatly different from those during off-peak hours. Considering that traffic demand changes with time and in different directions, arterials in this study were divided into one-way segments by the direction of flow, and time of day was differentiated and controlled for. In terms of data collection, traditional fixed-based methods have been widely used in previous studies, but they fail to capture the spatio-temporal distributions of speed along a road. A new approach is introduced to estimate speed variation by integrating spatio-temporal speed fluctuation of a single vehicle with speed differences between vehicles using taxi-based high frequency GPS data. With this approach, this paper aims to comprehensively establish a relationship between mean speed, speed variation and traffic crashes for the purpose of formulating effective speed management measures, specifically using an urban dataset. From a total of 234 one-way road segments from eight arterials in Shanghai, mean speed, speed variation, geometric design features, traffic volume, and crash data were collected. Because the safety effects of mean speed and speed variation may vary at different segment lengths, arterials with similar signal spacing density were grouped together. To account for potential correlations among these segments, a hierarchical Poisson log-normal model with random effects was developed. Results show that a 1% increase in mean speed on urban arterials was associated with a 0.7% increase in total crashes, and larger speed variation was also associated with increased crash frequency. Copyright © 2018 Elsevier Ltd. All rights

  18. 77 FR 13522 - Safety Zone; Baltimore Air Show, Patapsco River, Baltimore, MD

    Science.gov (United States)

    2012-03-07

    ... public event will consist of military and civilian aircraft performing low-flying, high-speed precision... Harbor. In addition to the air show dates, military and civilian aircraft performing in the air show will...[deg]14'30'' N, longitude 076[deg]36'30'' W; thence to the point of origin. This safety zone will be...

  19. When Schools Become Dead Zones of the Imagination: A Critical Pedagogy Manifesto

    Science.gov (United States)

    Giroux, Henry A.

    2016-01-01

    In this article Henry Giroux discusses corporate school reform movement and its detrimental impact on the public school system such as the closure of public schools in cities such as, Philadelphia, Chicago and New York to make way for charter schools. Giroux argues that corporate school reform is not simply obsessed with measurements that degrade…

  20. Reading component skills in dyslexia: word recognition, comprehension and processing speed.

    Science.gov (United States)

    de Oliveira, Darlene G; da Silva, Patrícia B; Dias, Natália M; Seabra, Alessandra G; Macedo, Elizeu C

    2014-01-01

    The cognitive model of reading comprehension (RC) posits that RC is a result of the interaction between decoding and linguistic comprehension. Recently, the notion of decoding skill was expanded to include word recognition. In addition, some studies suggest that other skills could be integrated into this model, like processing speed, and have consistently indicated that this skill influences and is an important predictor of the main components of the model, such as vocabulary for comprehension and phonological awareness of word recognition. The following study evaluated the components of the RC model and predictive skills in children and adolescents with dyslexia. 40 children and adolescents (8-13 years) were divided in a Dyslexic Group (DG; 18 children, MA = 10.78, SD = 1.66) and control group (CG 22 children, MA = 10.59, SD = 1.86). All were students from the 2nd to 8th grade of elementary school and groups were equivalent in school grade, age, gender, and IQ. Oral and RC, word recognition, processing speed, picture naming, receptive vocabulary, and phonological awareness were assessed. There were no group differences regarding the accuracy in oral and RC, phonological awareness, naming, and vocabulary scores. DG performed worse than the CG in word recognition (general score and orthographic confusion items) and were slower in naming. Results corroborated the literature regarding word recognition and processing speed deficits in dyslexia. However, dyslexics can achieve normal scores on RC test. Data supports the importance of delimitation of different reading strategies embedded in the word recognition component. The role of processing speed in reading problems remain unclear.

  1. Speed-calming measures and their Effect on driving speed

    DEFF Research Database (Denmark)

    Agerholm, Niels; Knudsen, Daniel; Variyeswaran, Kajan

    2017-01-01

    Highlights •Speed humps and chicanes are widespread speed-calming measures. •Humps and chicanes have virtually the same reducing effect on mean speed. •Chicanes reduce speed variation less than humps and might therefore be a less safe measure....

  2. Numerical comparisons of the performance of a hydraulic coupling with different pump rotational speeds

    International Nuclear Information System (INIS)

    Luo, Y; Feng, L H; Liu, S H; Chen, T J; Fan, H G

    2013-01-01

    A hydraulic coupling is a hydrodynamic device for transmitting rotating mechanical power. It is widely used in the machinery industry because of its advantages of high energy transmission efficiency, shock absorption and good adaptability, etc. In this paper, SIMPLEC algorithm and SST k-ω turbulence model were employed to simulate the steady state flows at operating conditions of two different rotational speeds (3000r/min and 7500 r/min) of the pump of a specified hydraulic coupling model. The results indicate the existence of similarity in the distributions of the flow fields between the two speeds, but the efficiency at the optimum condition is larger with higher rotational speed. It is concluded that the similarity principle of the efficiency of the hydraulic couplings does not apply in this case due to the relatively high rotating speed and small geometric specifications. It is also shown that the radially stratified pressure distribution on the torus section becomes more obvious with larger speed ratios, since the centrifugal movement plays more dominant roles over the circulating movement in these situations. When the speed ratio is small, with the completion of the circulating flow, the pressure distribution presents in a more circular pattern around the neutral zone of the torus section

  3. Improved work zone design guidelines and enhanced model of travel delays in work zones : Phase I, portability and scalability of interarrival and service time probability distribution functions for different locations in Ohio and the establishment of impr

    Science.gov (United States)

    2006-01-01

    The project focuses on two major issues - the improvement of current work zone design practices and an analysis of : vehicle interarrival time (IAT) and speed distributions for the development of a digital computer simulation model for : queues and t...

  4. Perception of the Transition Zones from Urban to Suburban Area Using Mobile Eye

    Directory of Open Access Journals (Sweden)

    Paolo Magris

    2014-12-01

    Full Text Available Road users adjust their driving behavior based on the perception of the route and the surrounding environment. The eye-tracking technology allows interpreting the driver behavior, analyzing aspects otherwise not considered in the design stage. This technology has been used for transition zone analysis at town entrances along the SP 610 “Selice Montanara”, to verify the efficiency of gateway created to reduce the input speed in urban areas. Results show that the installation of traffic calming measures at transition zones leads to a change of the environment perception by drivers, and consequently safety increase.

  5. "I Wanted to Go Here": Adolescents' Perspectives on School Choice

    Science.gov (United States)

    Mandic, Sandra; Sandretto, Susan; Hopkins, Debbie; Wilson, Gordon; Moore, Antoni; García Bengoechea, Enrique

    2018-01-01

    New Zealand legislation removing school zones radically reshaped school choice, resulting in increased school stratification from parental choice frequently driven by social factors such as ethnic makeup of the school community. This article considers school choice through the eyes of 1,465 adolescents from 12 secondary schools in Dunedin (New…

  6. The Effects of School Turnaround in Tennessee's Achievement School District and Innovation Zones

    Science.gov (United States)

    Zimmer, Ron; Henry, Gary T.; Kho, Adam

    2017-01-01

    In recent years, the federal government has invested billions of dollars to reform chronically low-performing schools. To fulfill their federal Race to the Top grant agreement, Tennessee implemented three turnaround strategies that adhered to the federal restart and transformation models: (a) placed schools under the auspices of the Achievement…

  7. Development of a high speed extrusion concept using a floating screw sleeve for solid-melt-separation

    Science.gov (United States)

    Karrenberg, Gregor; Wortberg, Johannes

    2015-05-01

    The High-Speed-S-Truder with floating screw sleeve is an alternative extrusion concept with solid-melt-separation. A fairly conventional 35 mm screw with a length of 21 D, which is accelerated by a 75 kW gearless, water cooled synchronous drive, conveys the resin into a 60 mm screw sleeve with a length of 10 D. Inside the sleeve the material is plasticizied and discharged into the outer screw channel of the sleeve through radial bores. Only the solid bed remains inside. The development of a melt pool - and thus a decrease of the plasticizing capacity - is avoided. The sleeve is rotated by drag forces only (approximately 10 - 15 % of the screw speed). Due to the low speed of the screw sleeve molten material is conveyed to a 4 D Dynamic Mixing Ring in a gentle manner. The DMRs floating ring and the screw sleeve are directly coupled. The granules in the screw channel are stopped by a barrier on the screw in front of the mixing device. So nearly no unmelted material can pass the system. For temperature management in the plastification and mixing zone a 3-zone heating/air-cooling system is used. Various kinds of experiments with the High-Speed S-Truder were conducted. Reachable throughputs with different types of material (LDPE, LLDPE, PP, PS) have been tested. Also three screw geometries, which are mainly varying in the channel depth, were compared. Experimental results and theoretical background will be described in this paper.

  8. Overall impact of speed-related initiatives and factors on crash outcomes.

    Science.gov (United States)

    D'Elia, A; Newstead, S; Cameron, M

    2007-01-01

    reinforce the benefits of reducing low level speeding - the central message of "Wipe Off 5". These strategies were implemented across the entire state of Victoria with the intention of covering as many road users as possible. This study aimed to evaluate the overall effectiveness of the speed-related package. The study objectives were: to document the increased speed camera activity in each speed limit zone and in Melbourne compared with the rest of Victoria; to evaluate the overall effect on crash outcomes of the package; to account as far as possible for the effect on crash outcomes of non-speed road safety initiatives and socio-economic factors, which would otherwise influence the speed-related package evaluation; and to examine speed trends in Melbourne and on Victorian rural highways, especially the proportions of vehicles travelling at excessive speeds. This paper presents the results of the evaluation of the overall impact on crash outcomes associated with the speed-related package, after adjusting as far as possible for the effect of non-speed road safety initiatives and socio-economic factors. D'Elia, Newstead and Cameron (2007) document the study results in full.

  9. Rotor aerodynamic power limits at low tip speed ratio using CFD

    International Nuclear Information System (INIS)

    Mikkelsen, Robert F; Sarmast, Sasan; Henningson, Dan; Sørensen, Jens N

    2014-01-01

    When investigating limits of rotor aerodynamic models, the Betz limit serves as a solid marker of an upper limit which no model should be able to exceed. A century ago Joukowsky (1912) proposed a rotor aerodynamic model utilizing a rotating actuator disc with a constant circulation. This model has since then been the subject of much controversy as it predicts a power performance that for all tip speed ratios exceeds the Betz limit and which goes to infinity when the tip speed ratio goes to zero. Recently, it was demonstrated that the Joukowsky model is fully consistent with the inviscid Euler equations and that the apparent inconsistency partly can be explained by the lack of viscous effects (Sprensen and van Kuik [4]). However, even including a term to account for the effect of viscosity at small tip speed ratios, the model still predicts a power yield that exceeds the Betz limit. In the present work we study in detail, using a CFD actuator line model, the flow behavior for rotors at small tip speed ratios. It is shown that the excessive swirl appearing towards the rotor center at small tip speed ratios generates vortex breakdown, causing a recirculating zone in the wake that limits the power yield of the rotor. The appearance of vortex breakdown has a similar effect on the flow behavior as the vortex ring state that usually appears at higher tip speed ratios. Limits to where vortex breakdown might occur with tip speed ratio and rotor loading as parameter are investigated and presented in the paper. The limits found correspond to well-known criterion for vortex breakdown onset for swirling flows in general. By applying a criterion for vortex breakdown in combination with the general momentum theory, the power performance always stays below the Betz limit

  10. Reading component skills in dyslexia: word recognition, comprehension and processing speed

    Directory of Open Access Journals (Sweden)

    Darlene Godoy Oliveira

    2014-11-01

    Full Text Available The cognitive model of reading comprehension posits that reading comprehension is a result of the interaction between decoding and linguistic comprehension. Recently, the notion of decoding skill was expanded to include word recognition. In addition, some studies suggest that other skills could be integrated into this model, like processing speed, and have consistently indicated that this skill influences and is an important predictor of the main components of the model, such as vocabulary for comprehension and phonological awareness of word recognition. The following study evaluated the components of the reading comprehension model and predictive skills in children and adolescents with dyslexia. 40 children and adolescents (8-13 years were divided in a Dyslexic Group (DG, 18 children, MA = 10.78, SD = 1.66 and Control Group (CG 22 children, MA = 10.59, SD = 1.86. All were students from the 2nd to 8th grade of elementary school and groups were equivalent in school grade, age, gender, and IQ. Oral and reading comprehension, word recognition, processing speed, picture naming, receptive vocabulary and phonological awareness were assessed. There were no group differences regarding the accuracy in oral and reading comprehension, phonological awareness, naming, and vocabulary scores. DG performed worse than the CG in word recognition (general score and orthographic confusion items and were slower in naming. Results corroborated the literature regarding word recognition and processing speed deficits in dyslexia. However, dyslexics can achieve normal scores on reading comprehension test. Data supports the importance of delimitation of different reading strategies embedded in the word recognition component. The role of processing speed in reading problems remain unclear.

  11. Resolution of gram quantities of racemates by high-speed counter-current chromatography.

    Science.gov (United States)

    Ma, Y; Ito, Y; Foucault, A

    1995-06-02

    Gram quantities of (+/-)-dinitrobenzoyl amino acids were separated by high-speed counter-current chromatography (CCC) using N-dodecanoyl-L-proline-3,5-dimethylanilide as a chiral selector (CS). Standard and pH-zone-refining CCC techniques were compared. By using the standard technique, 10 mg to a maximum of 1 g of samples was resolved in 2-9 h simply by increasing the concentration of the CS in the stationary phase. By using pH-zone-refining CCC, even more sample (2 g) was efficiently separated in less time (3 h). In both techniques, leakage of CS from the column was negligible. The method requires no solid support and the same column can be used repeatedly to separate a variety of enantiomers by dissolving appropriate chiral selectors in the stationary phase.

  12. Variable population exposure and distributed travel speeds in least-cost tsunami evacuation modelling

    Science.gov (United States)

    Fraser, Stuart A.; Wood, Nathan J.; Johnston, David A.; Leonard, Graham S.; Greening, Paul D.; Rossetto, Tiziana

    2014-01-01

    Evacuation of the population from a tsunami hazard zone is vital to reduce life-loss due to inundation. Geospatial least-cost distance modelling provides one approach to assessing tsunami evacuation potential. Previous models have generally used two static exposure scenarios and fixed travel speeds to represent population movement. Some analyses have assumed immediate departure or a common evacuation departure time for all exposed population. Here, a method is proposed to incorporate time-variable exposure, distributed travel speeds, and uncertain evacuation departure time into an existing anisotropic least-cost path distance framework. The method is demonstrated for hypothetical local-source tsunami evacuation in Napier City, Hawke's Bay, New Zealand. There is significant diurnal variation in pedestrian evacuation potential at the suburb level, although the total number of people unable to evacuate is stable across all scenarios. Whilst some fixed travel speeds approximate a distributed speed approach, others may overestimate evacuation potential. The impact of evacuation departure time is a significant contributor to total evacuation time. This method improves least-cost modelling of evacuation dynamics for evacuation planning, casualty modelling, and development of emergency response training scenarios. However, it requires detailed exposure data, which may preclude its use in many situations.

  13. Balancing High-Speed Rotors at Low Speed

    Science.gov (United States)

    Giordano, J.; Zorzi, E.

    1986-01-01

    Flexible balancing reduces vibrations at operating speeds. Highspeed rotors in turbomachines dynamically balanced at fraction of operating rotor speed. New method takes into account rotor flexible rather than rigid.

  14. Study of school zones with traffic signals : final report, June 2009.

    Science.gov (United States)

    2009-06-01

    One of the most pressing and controversial problems faced by parents, school administrators, law enforcement and transportation professionals throughout the country is the safety of children on their way to and from school. To proactively address thi...

  15. Biopower and School Surveillance Technologies 2.0

    Science.gov (United States)

    Hope, Andrew

    2016-01-01

    In recent years the proliferation, speed and reach of school-based surveillance devices has undergone what could be labelled as a revolution. Drawing upon Foucault's concept of biopower to explore the disciplining of bodies and the biopolitical management of populations, this paper examines "new" school surveillance technologies enabling…

  16. Application of Individualized Speed Thresholds to Interpret Position Specific Running Demands in Elite Professional Rugby Union: A GPS Study.

    Directory of Open Access Journals (Sweden)

    Cillian Reardon

    Full Text Available A number of studies have used GPS technology to categorise rugby union locomotive demands. However, the utility of the results of these studies is confounded by small sample sizes, sub-elite player status and the global application of absolute speed thresholds to all player positions. Furthermore, many of these studies have used GPS units with low sampling frequencies. The aim of the present study was to compare and contrast the high speed running (HSR demands of professional rugby union when utilizing micro-technology units sampling at 10 Hz and applying relative or individualised speed zones. The results of this study indicate that application of individualised speed zones results in a significant shift in the interpretation of the HSR demands of both forwards and backs and positional sub-categories therein. When considering the use of an absolute in comparison to an individualised HSR threshold, there was a significant underestimation for forwards of HSR distance (HSRD (absolute = 269 ± 172.02, individualised = 354.72 ± 99.22, p < 0.001, HSR% (absolute = 5.15 ± 3.18, individualised = 7.06 ± 2.48, p < 0.001 and HSR efforts (HSRE (absolute = 18.81 ± 12.25; individualised = 24.78 ± 8.30, p < 0.001. In contrast, there was a significant overestimation of the same HSR metrics for backs with the use of an absolute threshold (HSRD absolute = 697.79 ± 198.11, individualised = 570.02 ± 171.14, p < 0.001; HSR% absolute = 10.85 ± 2.82, individualised = 8.95 ± 2.76, p < 0.001; HSRE absolute = 41.55 ± 11.25; individualised = 34.54 ± 9.24, p < 0.001. This under- or overestimation associated with an absolute speed zone applies to varying degrees across the ten positional sub-categories analyzed and also to individuals within the same positional sub-category. The results of the present study indicated that although use of an individulised HSR threshold improves the interpretation of the HSR demands on a positional basis, inter

  17. Monitoring speed before and during a speed publicity campaign.

    NARCIS (Netherlands)

    Schagen, I.N.L.G. van Commandeur, J.J.F. Goldenbeld, C. & Stipdonk, H.

    2016-01-01

    Driving speeds were monitored during a period of 16 weeks encompassing different stages of an anti-speeding campaign in the Netherlands. This campaign targeted speed limit violations in built-up areas. The observation periods differed in terms of intensity and media used for the campaign. Small

  18. Pay as You Speed, ISA with incentives for not speeding

    DEFF Research Database (Denmark)

    Lahrmann, Harry Spaabæk; Agerholm, Niels; Tradisauskas, Nerius

    2012-01-01

    The Intelligent Speed Adaptation (ISA) project we describe in this article is based on Pay as You Drive principles. These principles assume that the ISA equipment informs a driver of the speed limit, warns the driver when speeding and calculates penalty points. Each penalty point entails the redu......The Intelligent Speed Adaptation (ISA) project we describe in this article is based on Pay as You Drive principles. These principles assume that the ISA equipment informs a driver of the speed limit, warns the driver when speeding and calculates penalty points. Each penalty point entails...... the reduction of a 30% discount on the driver's car insurance premium, which therefore produced the name, Pay as You Speed. The ISA equipment consists of a GPS-based On Board Unit with a mobile phone connection to a web server. The project was planned for a three-year test period with 300 young car drivers...

  19. Attitudes of School Administrators and Teachers towards the "Smoke-Free Air Zone" Policy in Turkish Schools

    Science.gov (United States)

    Banoglu, Köksal

    2013-01-01

    Objective: Schools are likely to be better able to achieve compliance with smoke-free regulations if principals and teachers perceive the importance of a smoke-free policy. The purpose of this study was to measure teacher and administrator attitudes towards the smoke-free policy in Turkish schools, which promotes a total smoking ban. Method: The…

  20. The Current Practices and Problems of School Based Supervision in ...

    African Journals Online (AJOL)

    The purpose of this study was to identify the current practice and problems of school based supervision in government primary schools of Jile Timuga Woreda of Oromia Zone. A descriptive survey design of research methodology was employed. Regarding sampling, there were 39 primary schools grouped in 10 cluster ...

  1. Improving Working Memory and Processing Speed of Students with Dyslexia in Nigeria

    Science.gov (United States)

    Adubasim, Ijeoma

    2018-01-01

    This study investigated effective strategies for improving working memory and processing speed of students identified with dyslexia in Nigeria. The study adopted a quasi-experimental research design with the population made up of twenty four thousand seven hundred and twenty seven (24,727) senior secondary school students (S.S.2) in all the public…

  2. Mitigating the negative impacts of tall wind turbines on bats: Vertical activity profiles and relationships to wind speed.

    Science.gov (United States)

    Wellig, Sascha D; Nusslé, Sébastien; Miltner, Daniela; Kohle, Oliver; Glaizot, Olivier; Braunisch, Veronika; Obrist, Martin K; Arlettaz, Raphaël

    2018-01-01

    Wind turbines represent a source of hazard for bats, especially through collision with rotor blades. With increasing technical development, tall turbines (rotor-swept zone 50-150 m above ground level) are becoming widespread, yet we lack quantitative information about species active at these heights, which impedes proposing targeted mitigation recommendations for bat-friendly turbine operation. We investigated vertical activity profiles of a bat assemblage, and their relationships to wind speed, within a major valley of the European Alps where tall wind turbines are being deployed. To monitor bat activity we installed automatic recorders at sequentially increasing heights from ground level up to 65 m, with the goal to determine species-specific vertical activity profiles and to link them to wind speed. Bat call sequences were analysed with an automatic algorithm, paying particular attention to mouse-eared bats (Myotis myotis and Myotis blythii) and the European free-tailed bat (Tadarida teniotis), three locally rare species. The most often recorded bats were the Common pipistrelle (Pipistrellus pipistrellus) and Savi's pipistrelle (Hypsugo savii). Mouse-eared bats were rarely recorded, and mostly just above ground, appearing out of risk of collision. T. teniotis had a more evenly distributed vertical activity profile, often being active at rotor level, but its activity at that height ceased above 5 ms-1 wind speed. Overall bat activity in the rotor-swept zone declined with increasing wind speed, dropping below 5% above 5.4 ms-1. Collision risk could be drastically reduced if nocturnal operation of tall wind turbines would be restricted to wind speeds above 5 ms-1. Such measure should be implemented year-round because T. teniotis remains active in winter. This operational restriction is likely to cause only small energy production losses at these tall wind turbines, although further analyses are needed to assess these losses precisely.

  3. Speed in Acquisitions

    DEFF Research Database (Denmark)

    Meglio, Olimpia; King, David R.; Risberg, Annette

    2017-01-01

    The advantage of speed is often invoked by academics and practitioners as an essential condition during post-acquisition integration, frequently without consideration of the impact earlier decisions have on acquisition speed. In this article, we examine the role speed plays in acquisitions across...... the acquisition process using research organized around characteristics that display complexity with respect to acquisition speed. We incorporate existing research with a process perspective of acquisitions in order to present trade-offs, and consider the influence of both stakeholders and the pre......-deal-completion context on acquisition speed, as well as the organization’s capabilities to facilitating that speed. Observed trade-offs suggest both that acquisition speed often requires longer planning time before an acquisition and that associated decisions require managerial judgement. A framework for improving...

  4. Household food insecurity and its association with morbidity report among school adolescent in Jimma zone, Ethiopia.

    Science.gov (United States)

    Tamiru, Dessalegn; Belachew, Tefera

    2018-01-13

    Background Household food insecurity has a substantial contribution to poor health outcomes among young children and adolescents. Food insecurity also affects optimal cognitive development and physiological function of these vulnerable groups. There is a gap of documented data regarding the association of food insecurity and morbidity among school adolescents in Ethiopia. Objective The aim of this study is to assess the interrelationship of household food insecurity and morbidity report among school adolescent in Jimma zone, Ethiopia. Methods A community based cross-sectional study was done from October to November, 2013. Data were gathered using structured questionnaires through interview of students and their caregivers. A total of 1000 students were selected by using simple random sampling methods using their rosters as a frame. Data were also checked for missing values and outliers, and analyzed using SPSS version 16.0. Regression analyses were used to see the strength of association between independent and dependent variables using odds ratios and 95% of confidence intervals. Results Adolescents from food insecure households had more reported illness (39.3%) than adolescents from food secure households (24.7%) (p insecure households were two times more exposed to morbidity [AOR = 2.04(1.32, 3.14)] than adolescents from food secure households. This study also showed that males had 48% less reported illness [AOR = 0.52(0.01, 0.23)] than females. Adolescents who had attended health education had less reported illness [AOR = 0.57(0.38, 0.86)] than those who did not ever attend. This study also showed that having a farmer [AOR = 0.46(0.28, 0.74)] and government employee [AOR = 0.33 (0.17, 0.64)] father were inversely associated with adolescent morbidity. Conclusion The findings of this study showed that household food insecurity, female gender and lack of attending health education had a significant contribution to adolescent morbidity. Therefore, there is a need

  5. Children eat their school lunch too quickly: an exploratory study of the effect on food intake

    Directory of Open Access Journals (Sweden)

    Zandian Modjtaba

    2012-05-01

    Full Text Available Abstract Background Speed of eating, an important aspect of eating behaviour, has recently been related to loss of control of food intake and obesity. Very little time is allocated for lunch at school and thus children may consume food more quickly and food intake may therefore be affected. Study 1 measured the time spent eating lunch in a large group of students eating together for school meals. Study 2 measured the speed of eating and the amount of food eaten in individual school children during normal school lunches and then examined the effect of experimentally increasing or decreasing the speed of eating on total food intake. Methods The time spent eating lunch was measured with a stop watch in 100 children in secondary school. A more detailed study of eating behaviour was then undertaken in 30 secondary school children (18 girls. The amount of food eaten at lunch was recorded by a hidden scale when the children ate amongst their peers and by a scale connected to a computer when they ate individually. When eating individually, feedback on how quickly to eat was visible on the computer screen. The speed of eating could therefore be increased or decreased experimentally using this visual feedback and the total amount of food eaten measured. Results In general, the children spent very little time eating their lunch. The 100 children in Study 1 spent on average (SD just 7 (0.8 minutes eating lunch. The girls in Study 2 consumed their lunch in 5.6 (1.2 minutes and the boys ate theirs in only 6.8 (1.3 minutes. Eating with peers markedly distorted the amount of food eaten for lunch; only two girls and one boy maintained their food intake at the level observed when the children ate individually without external influences (258 (38 g in girls and 289 (73 g in boys. Nine girls ate on average 33% less food and seven girls ate 23% more food whilst the remaining boys ate 26% more food. The average speed of eating during school lunches amongst groups

  6. Children eat their school lunch too quickly: an exploratory study of the effect on food intake.

    Science.gov (United States)

    Zandian, Modjtaba; Ioakimidis, Ioannis; Bergström, Jakob; Brodin, Ulf; Bergh, Cecilia; Leon, Michael; Shield, Julian; Södersten, Per

    2012-05-14

    Speed of eating, an important aspect of eating behaviour, has recently been related to loss of control of food intake and obesity. Very little time is allocated for lunch at school and thus children may consume food more quickly and food intake may therefore be affected. Study 1 measured the time spent eating lunch in a large group of students eating together for school meals. Study 2 measured the speed of eating and the amount of food eaten in individual school children during normal school lunches and then examined the effect of experimentally increasing or decreasing the speed of eating on total food intake. The time spent eating lunch was measured with a stop watch in 100 children in secondary school. A more detailed study of eating behaviour was then undertaken in 30 secondary school children (18 girls). The amount of food eaten at lunch was recorded by a hidden scale when the children ate amongst their peers and by a scale connected to a computer when they ate individually. When eating individually, feedback on how quickly to eat was visible on the computer screen. The speed of eating could therefore be increased or decreased experimentally using this visual feedback and the total amount of food eaten measured. In general, the children spent very little time eating their lunch. The 100 children in Study 1 spent on average (SD) just 7 (0.8) minutes eating lunch. The girls in Study 2 consumed their lunch in 5.6 (1.2) minutes and the boys ate theirs in only 6.8 (1.3) minutes. Eating with peers markedly distorted the amount of food eaten for lunch; only two girls and one boy maintained their food intake at the level observed when the children ate individually without external influences (258 (38) g in girls and 289 (73) g in boys). Nine girls ate on average 33% less food and seven girls ate 23% more food whilst the remaining boys ate 26% more food. The average speed of eating during school lunches amongst groups increased to 183 (53)% in the girls and to 166 (47

  7. Zone separator for multiple zone vessels

    Science.gov (United States)

    Jones, John B.

    1983-02-01

    A solids-gas contact vessel, having two vertically disposed distinct reaction zones, includes a dynamic seal passing solids from an upper to a lower zone and maintaining a gas seal against the transfer of the separate treating gases from one zone to the other, and including a stream of sealing fluid at the seal.

  8. The estimated evacuation time for the emergency planning zone of the Kori nuclear site, with a focus on the precautionary action zone

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jang Hee; Jeong, Jae Jun [School of Mechanical Engineering, Pusan National University, Busan (Korea, Republic of); Shin, Won Ki; Song, Eun Young; Cho, Cheol Woo [Div. of Nuclear Safety, Busan Metropolitan City, Busan (Korea, Republic of)

    2016-09-15

    The emergency planning zone (EPZ) of the city of Busan is divided into the precautionary actions zone (PAZ) and the urgent protective action planning zone; which have a 5-km radius and a 20-km to 21-km radius from the nuclear power plant site, respectively. In this study, we assumed that a severe accident occurred at Shin-Kori nuclear unit 3 and evaluated the dispersion speed of radiological material at each distance at various wind speeds, and estimated the effective dose equivalent and the evacuation time of PAZ residents with the goal of supporting off-site emergency action planning for the nuclear site. The total effective dose equivalent, which shows the effect of released radioactive materials on the residents, was evaluated using the RASCAL 4.2 program. In addition, a survey of 1,036 residents was performed using a standardized questionnaire, and the resident evacuation time according to road and distance was analyzed using the VISSIM 6.0 program. According to the results obtained using the VISSIM and RASCAL programs, it would take approximately 80 to 252.2 minutes for permanent residents to move out of the PAZ boundary, 40 to 197.2 minutes for students, 60 to 232.2 minutes for the infirm, such as elderly people and those in a nursing home or hospital, and 30 to 182.2 minutes for those temporarily within the area. Consequently, in the event of any delay in the evacuation, it is estimated that the residents would be exposed to up to 10 mSv·h-1 of radiation at the Exclusion Area Boundaries (EAB) boundary and 4-6 mSv·h-1 at the PAZ boundary. It was shown that the evacuation time for the residents is adequate in light of the time lapse from the initial moment of a severe accident to the radiation release. However, in order to minimize the evacuation time, it is necessary to maintain a system of close collaboration to avoid traffic congestion and spontaneous evacuation attempts.

  9. The estimated evacuation time for the emergency planning zone of the Kori nuclear site, with a focus on the precautionary action zone

    International Nuclear Information System (INIS)

    Lee, Jang Hee; Jeong, Jae Jun; Shin, Won Ki; Song, Eun Young; Cho, Cheol Woo

    2016-01-01

    The emergency planning zone (EPZ) of the city of Busan is divided into the precautionary actions zone (PAZ) and the urgent protective action planning zone; which have a 5-km radius and a 20-km to 21-km radius from the nuclear power plant site, respectively. In this study, we assumed that a severe accident occurred at Shin-Kori nuclear unit 3 and evaluated the dispersion speed of radiological material at each distance at various wind speeds, and estimated the effective dose equivalent and the evacuation time of PAZ residents with the goal of supporting off-site emergency action planning for the nuclear site. The total effective dose equivalent, which shows the effect of released radioactive materials on the residents, was evaluated using the RASCAL 4.2 program. In addition, a survey of 1,036 residents was performed using a standardized questionnaire, and the resident evacuation time according to road and distance was analyzed using the VISSIM 6.0 program. According to the results obtained using the VISSIM and RASCAL programs, it would take approximately 80 to 252.2 minutes for permanent residents to move out of the PAZ boundary, 40 to 197.2 minutes for students, 60 to 232.2 minutes for the infirm, such as elderly people and those in a nursing home or hospital, and 30 to 182.2 minutes for those temporarily within the area. Consequently, in the event of any delay in the evacuation, it is estimated that the residents would be exposed to up to 10 mSv·h-1 of radiation at the Exclusion Area Boundaries (EAB) boundary and 4-6 mSv·h-1 at the PAZ boundary. It was shown that the evacuation time for the residents is adequate in light of the time lapse from the initial moment of a severe accident to the radiation release. However, in order to minimize the evacuation time, it is necessary to maintain a system of close collaboration to avoid traffic congestion and spontaneous evacuation attempts

  10. Propagation speed and incident direction of transient ionospheric disturbance (TID)

    International Nuclear Information System (INIS)

    Maeda, Sawako; Handa, Shun.

    1978-01-01

    It is well known that large scale transient ionospheric disturbance (ls-TID) of period from 20 min to 3 hours and spatial wave length from hundreds to thousands km among TID's is in close correlation to geomagnetic activity at high latitude. Since TID well agrees with the wave characteristic of internal gravitational waves, it has come to be considered that the internal gravitational waves excited by Lorentz's force and joule heating due to the ionospheric current in auroral zone at the time of substorm cause disturbances to ionosphere electron density. The authors have examined the propagation speed and incident direction of TID using the data observed at 5 min intervals of maximum electron density in F layer during IGY (international geophysical year). The data was processed through a band pass filter because only the waves with period from 20 min to 3 hours were required. Since two proposed modes for ls-TID have been discussed, whose dispersion properties are different, it is necessary to determine the propagation characteristics of ls-TID by observation, and to clarify the propagation mechanism of internal gravitational waves. Therefore, the dependence of propagation speed on period has been investigated. It is concluded that ls-TID was observed at the time of polar magnetic field disturbances, the average propagation speed was about 500 m/s and the incident direction was north-north east for the variation of from 20 min to 3 hours, and as for the dependence of propagation speed on period, the average speed was about 670 m/s for the long period change (approximately 100 min period), and about 440 m/s for short period change (approximately 30 min period) and the dispersion was observed. (Wakatsuki, Y.)

  11. Strength, running speed, agility and balance profiles of 9- to 10-year ...

    African Journals Online (AJOL)

    The purpose of this study was to determine the strength, running speed and agility, and balance profiles of 9- to 10-year old learners and the relation between these skills of the learners. Using a stratified random selection from 20 schools with different socio-economic backgrounds, 862 9- to 10-year-old learners (457 boys; ...

  12. Article 7: Measures of digit span and verbal rehearsal speed in deaf children following more than 10 years of cochlear implantation

    Science.gov (United States)

    Pisoni, David; Kronenberger, William; Roman, Adrienne; Geers, Ann

    2011-01-01

    Precis This paper reports results on the development of immediate memory capacity and verbal rehearsal speed in 112 children with more than ten years of CI use. We found less than half of the sample showed increases in both forward and backward digit spans suggesting disturbances in basic mechanisms related to storage or rehearsal of verbal information. Both spans and verbal rehearsal speeds in elementary school were found to be correlated with speech and language outcomes in high school. These developmental results provide new insights in the elementary neurocognitive information processes associated with high variability in speech and language outcomes. PMID:21832890

  13. Demand and Supply of Teachers to Secondary Schools in Anambra ...

    African Journals Online (AJOL)

    This study investigated the demand and supply of teachers to secondary schools in Anambra State of Nigeria due to school type. The survey design approach was adopted for this study. The population of the study comprised of all the secondary school principals, numbering 259 in the six education zones of Anambra State.

  14. The Role of Search Speed in the Contextual Cueing of Children's Attention.

    Science.gov (United States)

    Darby, Kevin; Burling, Joseph; Yoshida, Hanako

    2014-01-01

    The contextual cueing effect is a robust phenomenon in which repeated exposure to the same arrangement of random elements guides attention to relevant information by constraining search. The effect is measured using an object search task in which a target (e.g., the letter T) is located within repeated or nonrepeated visual contexts (e.g., configurations of the letter L). Decreasing response times for the repeated configurations indicates that contextual information has facilitated search. Although the effect is robust among adult participants, recent attempts to document the effect in children have yielded mixed results. We examined the effect of search speed on contextual cueing with school-aged children, comparing three types of stimuli that promote different search times in order to observe how speed modulates this effect. Reliable effects of search time were found, suggesting that visual search speed uniquely constrains the role of attention toward contextually cued information.

  15. Evaluating Sea water Quality in the Coastal Zone of North Lebanon using Telemac-2DTM

    International Nuclear Information System (INIS)

    Awad, Mohamad; Darwich, T.

    2009-01-01

    The coastal zones of the Mediterranean are undergoing rapid development withgrowing and conflicting demands on the natural resources. Coastal zones are often subjected to irreversible land degradation and environmental deterioration. Lebanon is located in the eastern part of the Mediterranean basin and the integrated management of the environment in the Lebanese coastal zone must be given concern. Most of the successful decisions addressing the environment protection or the elaboration of preventive measures in the coastal zone. These decisions depend on the availability of efficient simulation tools. The existence of these tools can help protecting the environment and establishing the ground for sustainable natural resources in the coastal zones. In this paper, a simulation tool called Telemac-2D TM software was used to simulate the business as usual, pessimistic, and optimistic status of the sea water quality in the coastal zone of Tripoli (North Lebanon). The coastal zone is affected by the effluents of solid and liquid wastes from Abou-Ali river. The different quality states of the coastal zone represent the normal, high, and low flow of the effluents (plume pollutants) from Abou-Ali river. In addition, it represents the variation of different factors such as wind and sea currents speed and direction. This simulation will help the decision makers to implement pre-cautious measures before a disaster takes place by assessing the quality of the sea water near the coastal zones. (author)

  16. 76 FR 54375 - Safety Zone; Thunder on the Gulf, Gulf of Mexico, Orange Beach, AL

    Science.gov (United States)

    2011-09-01

    ...-AA00 Safety Zone; Thunder on the Gulf, Gulf of Mexico, Orange Beach, AL AGENCY: Coast Guard, DHS... portion of the Gulf of Mexico for the waters off Orange Beach, Alabama. This action is necessary for the... conduct a high speed boat race on the Gulf of Mexico, south of Orange Beach, Alabama to occur from October...

  17. Using a cylindrical vortex model to assess the induction zone infront of aligned and yawed rotors

    DEFF Research Database (Denmark)

    Branlard, Emmanuel Simon Pierre; Meyer Forsting, Alexander Raul

    2015-01-01

    . The mean relative error is estimated in the induction zone and foundto be below 0.4% for the aligned flows tested and below 1.3% for the yawed test cases. Thecomputational time required by the analytical model is in the order of thousands of timesless than the one required by the actuator disk simulation.......Analytical formulae for the velocity field induced by a cylindrical vortex wake model areapplied to assess the induction zone in front of aligned and yawed rotors. The results arecompared to actuator disk (AD) simulations for different operating conditions, includingfinite tip-speed ratios...

  18. Parapapillary atrophy: histological gamma zone and delta zone.

    Directory of Open Access Journals (Sweden)

    Jost B Jonas

    Full Text Available BACKGROUND: To examine histomorphometrically the parapapillary region in human eyes. METHODOLOGY/PRINCIPAL FINDINGS: The histomorphometric study included 65 human globes (axial length:21-37 mm. On anterior-posterior histological sections, we measured the distance Bruch's membrane end (BME-optic nerve margin ("Gamma zone", BME-retinal pigment epithelium (RPE ("Beta zone", BME-beginning of non-occluded choriocapillaris, and BME-beginning of photoreceptor layer. "Delta zone" was defined as part of gamma zone in which blood vessels of at least 50 µm diameter were not present over a length of >300 µm. Beta zone (mean length:0.35±0.52 mm was significantly (P = 0.01 larger in the glaucoma group than in the non-glaucomatous group. It was not significantly (P = 0.28 associated with axial length. Beta zone was significantly (P = 0.004 larger than the region with occluded choriocapillaris. Gamma zone (mean length:0.63±1.25 mm was associated with axial length (P50 µm diameter within gamma zone was present only in highly axially elongated globes and was not related with glaucoma. Beta zone (Bruch's membrane without RPE was correlated with glaucoma but not with globe elongation. Since the region with occluded choriocapillaris was smaller than beta zone, complete loss of RPE may have occurred before complete choriocapillaris closure.

  19. Speed and income

    DEFF Research Database (Denmark)

    Fosgerau, Mogens

    2005-01-01

    The relationship between speed and income is established in a microeconomic model focusing on the trade-off between travel time and the risk of receiving a penalty for exceeding the speed limit. This is used to determine when a rational driver will choose to exceed the speed limit. The relationship...... between speed and income is found again in the empirical analysis of a cross-sectional dataset comprising 60,000 observations of car trips. This is used to perform regressions of speed on income, distance travelled, and a number of controls. The results are clearly statistically significant and indicate...... an average income elasticity of speed of 0.02; it is smaller at short distances and about twice as large at the longest distance investigated of 200 km....

  20. Status Of Strategic Management Practices Of Secondary School ...

    African Journals Online (AJOL)

    The purpose of the study was to determine the extent to which principals practice strategic management skills in students' administration in secondary schools in Anambra State. All the two hundred and fifty-nine (259) secondary school principals of the six education zones of Anambra State were used for the study.

  1. Wind effects on coastal zone color scanner chlorophyll patterns in the U.S. Mid-Atlantic Bight during spring 1979

    Science.gov (United States)

    Eslinger, David L.; Iverson, Richard L.

    1986-01-01

    Coastal zone color scanner (CZCS) chlorophyll concentration increases in the Mid-Atlantic Bight were associated with high wind speeds in continental shelf waters during March and May 1979. Maximum spring CZCS chlorophyll concentrations occurred during April when the water column was not thermally stratified and were spatially and temporally associated with reductions in wind speed both in onshelf and in offshelf regions. Increased chlorophyll concentrations in offshelf waters were associated with high wind speeds during May when a deep chlorophyll maximum was present. Chlorophyll patchiness was observed on length scales typical of those controlled by biological processes during the April low-wind period but not during March or May when wind speeds were greater. The spring CZCS chlorophyll maximum in the southern portion of the Mid-Atlantic Bight occurred in response to a reduction in mixed layer depth caused by decreased wind speeds and not by increased water column stratification.

  2. School Brand Management: The Policies, Practices, and Perceptions of Branding and Marketing in New York City's Public High Schools

    Science.gov (United States)

    DiMartino, Catherine; Jessen, Sarah Butler

    2016-01-01

    Over the past 20 years, market-based choice initiatives have become a popular approach to education reform. Since 2002, the New York City Department of Education has opened over 250 high schools, creating a marketplace so widespread that many students no longer have a zoned or neighborhood school. This article uses two New York City--based case…

  3. Effecten van inrichting tot 30 km/uur zone in 15 experimentele gebieden : een evaluatiestudie op basis van integratie van resultaten uit verkeerskundige studies, bewonersonderzoeken en een ongevallenanalyse.

    NARCIS (Netherlands)

    Vis, A.A.

    1992-01-01

    Dutch municipal authorities have been able to institute a maximum speed of 30 km/h roads in zones within built-up areas, since the year 1984. The safety effects of 30 km/h zones are positive. In order to be sure about this, the Ministry of Transport and Public Works has encouraged 15 municipalities

  4. Pay as You Speed, ISA with incentive for not speeding

    DEFF Research Database (Denmark)

    Lahrmann, Harry Spaabæk; Agerholm, Niels; Tradisauskas, Nerius

    2012-01-01

    To simulate a market introduction of Intelligent Speed Adaptation (ISA) and to study the effect of a Pay as You Speed (PAYS) concept, a field trial with 153 drivers was conducted during 2007–2009. The participants drove under PAYS conditions for a shorter or a longer period. The PAYS concept......, with and without incentive crossed with informative ISA present or absent. The results showed that ISA is an efficient tool for reducing speeding particularly on rural roads. The analysis of speed data demonstrated that the proportion of distance driven above the speed where the ISA equipment responded (PDA...... level. Both informative ISA and incentive ISA reduced the PDA, but there was no statistically significant interaction. Informative reduced it more than the incentive....

  5. School choice & social stratification: how intra-district transfers shift the racial/ethnic and economic composition of schools.

    Science.gov (United States)

    Phillips, Kristie J R; Larsen, Elisabeth S; Hausman, Charles

    2015-05-01

    The liberation model hypothesizes that school choice liberates students from underperforming schools by giving them the opportunity to seek academically superior schooling options outside of their neighborhoods. Subsequently, school choice is hypothesized to diminish stratification in schools. Data from one urban school district is analyzed to test these hypotheses. We specifically examine which factors influence the propensity for parents to participate in choice, and how school choice changes the racial/ethnic and economic composition of schools. We further examine how school choice influences similar changes within distinct sociogeographic areas within the district. We find that families who are zoned to more racially/ethnically and economically diverse schools in sociogeographically diverse areas are more likely to participate in school choice. We also find that intra-district choice is associated with a slight increase in social stratification throughout the district, with more substantial stratification occurring in the most demographically diverse areas and schools. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Kinematics and energetic benefits of schooling in the labriform fish, striped surfperch Embiotoca lateralis

    DEFF Research Database (Denmark)

    Johansen, J. L.; Vaknin, R.; Steffensen, John Fleng

    2010-01-01

    Schooling can provide fish with a number of behavioural and ecological advantages, including increased food supply and reduced predator risk. Previous work suggests that fish swimming using body and caudal fin locomotion may also experience energetic advantages when trailing behind neighbours......, based on correlations between swimming speeds and pectoral fin beat frequency and between swimming speeds and oxygen consumption of solitary fish. In addition, leading individuals in a school were estimated to have higher oxygen consumption than solitary individuals swimming at the same speed, based....... However, little is known about the potential energetic advantages associated with schooling in fish that swim using their pectoral fins. Using the striped surfperch Embiotoca lateralis, a labriform fish that swims routinely with its pectoral fins, we found that pectoral fin beat frequencies were...

  7. New Observations on High-Speed Machining of Hardened AISI 4340 Steel Using Alumina-Based Ceramic Tools

    Directory of Open Access Journals (Sweden)

    Mohamed Shalaby

    2018-05-01

    Full Text Available High-speed machining (HSM is used in industry to improve the productivity and quality of the cutting operations. In this investigation, pure alumina ceramics with the addition of ZrO2, and mixed alumina (Al2O3 + TiC tools were used in the dry hard turning of AISI 4340 (52 HRC at different high cutting speeds of 150, 250, 700 and 1000 m/min. It was observed that at cutting speeds of 150 and 250 m/min, pure alumina ceramic tools had better wear resistance than mixed alumina ones. However, upon increasing the cutting speed from 700 to 1000 m/min, mixed alumina ceramic tools outperformed pure ceramic ones. Scanning electron microscopy (SEM and X-ray photoelectron spectroscopy (XPS were used to investigate the worn cutting edges and analyze the obtained results. It was found that the tribo-films formed at the cutting zone during machining affected the wear resistances of the tools and influenced the coefficient of friction at the tool-chip interface. These observations were confirmed by the chip compression ratio results at different cutting conditions. Raising cutting speed to 1000 m/min corresponded to a remarkable decrease in cutting force components in the dry hard turning of AISI 4340 steel.

  8. Fluid-mediated stability and speed-increase for heaving hydrofoils swimming side-by-side

    Science.gov (United States)

    Newbolt, Joel; Zhang, Jun; Ristroph, Leif

    2017-11-01

    As an example of collective motion in active swimmers we study the fluid-mediated interaction between two heaving hydrofoils that swim with a fixed transverse separation (between the heaving mid-heights) but are free to independently choose their forward swimming speeds and positions. Experiments reveal that out-of-phase foils are attracted to a side-by-side configuration which also increases the swimming speed of the pair (up to 59% faster for our parameters), while in-phase foils are repelled from this configuration. Because this type of swimming is qualitatively similar to that of fish and birds this interaction could be important to schooling and flocking.

  9. Effect of tool rotational speed on force generation, microstructure and mechanical properties of friction stir welded Al–Mg–Cr–Mn (AA 5052-O) alloy

    International Nuclear Information System (INIS)

    Moshwan, Raza; Yusof, Farazila; Hassan, M.A.; Rahmat, S.M.

    2015-01-01

    Highlights: • 3 mm thick AA 5052-O alloy plates were successfully joined by FSW process. • The joint was produced at 1000 rpm yielded a maximum tensile strength of 132 MPa. • The dissolution of β-Mg 2 Al 3 intermetallic phases of FSWed joints were reported. • Different axial forces acted on welding tool during welding were investigated. - Abstract: Friction stir welding (FSW) between 3 mm thick AA 5052-O aluminum alloy plates was investigated in the present study. Different welded specimens were produced by employing a constant tool traverse speed of 120 mm/min and by varying rotating speeds from 800 to 3000 rpm. The welded joints were characterized by its appearances, microstructural and mechanical properties at room temperature. The measurement of different forces acted on the tool during the FSW of AA 5052-O plates provided a significant insight to determine the quality of the welded joints. From the appearances of the welded joints it was evident that, except the tool rotational speed of 3000 rpm all other rotational speeds produced sound welded joints with smooth surface. The joint produced at 1000 rpm yielded a maximum tensile strength of 132 MPa which was 74% of the base material strength. Field emission scanning electron microscopy (FESEM) and energy dispersive spectroscopy (EDS) analyses on the stir zone suggested that, β-Mg 2 Al 3 intermetallic phases of the base material were mechanically fractured, smeared and mixed to different geometries due to tool stirring. The dissolution and redistribution of β-Mg 2 Al 3 second phase particles in the stir zone had a considerable effect on the reduction of the tensile strength of the welded joints. The reduction in hardness at the nugget zone (NZ) of the welded joints under different tool rotational speeds could be attributed to the dislocation of Mg-rich phases and segregation of Mg solute atoms at grain boundaries, which drew solute Mg atoms away from the α-aluminum matrix

  10. Effects of Turbulent Reynolds Number on the Displacement Speed Statistics in the Thin Reaction Zones Regime of Turbulent Premixed Combustion

    Directory of Open Access Journals (Sweden)

    Nilanjan Chakraborty

    2011-01-01

    nature of the correlations remains unaffected. The dependence of displacement speed on strain rate and curvature is found to weaken with increasing turbulent Reynolds number when either Damköhler or Karlovitz number is held constant, but the qualitative nature of the correlation remains unaltered. The implications of turbulent Reynolds number effects in the context of Flame Surface Density (FSD modelling have also been addressed, with emphasis on the influence of displacement speed on the curvature and propagation terms in the FSD balance equation.

  11. Comparison of performances of full-speed turbine and half-speed turbine for nuclear power plants

    International Nuclear Information System (INIS)

    Wang Hu; Zhang Weihong; Zhang Qiang; Li Shaohua

    2010-01-01

    The steam turbines of nuclear power plants can be divided into the full-speed turbine and half-speed turbine. Different speed leads to differences in many aspects. Therefore, the rational speed is the key point in the selection of steam turbines. This paper contrasts the economy between the half-speed turbine and full-speed turbine, by calculating the relative internal efficiency of half-speed and full-speed steam turbines with the typical level of 1000 megawatt. At the same time, this paper also calculate the relative speed of high speed water drops in the last stage blade of half-speed turbine and full-speed turbine, to contrast the water erosion between the half-speed turbine and full-speed turbine. The results show that the relative internal efficiency of half-speed turbine is higher than that of the full-speed turbine, and that the security especially the ability of preventing water erosion of half-speed turbine is better than that of the full-speed turbine. (authors)

  12. Een paar kilometer snelheidsdaling bij een school : so what ?

    NARCIS (Netherlands)

    Oei, H.-l.

    1989-01-01

    An experiment was held in The Hague near a school complex with three speed signs. All these signs resulted in a reduction of the speed of cars. It may be assumed that this reduction will result in a reduction of the probability of an accident and injury and of the injury-severity. The quantitative

  13. Influence of Tool Rotational Speed and Post-Weld Heat Treatments on Friction Stir Welded Reduced Activation Ferritic-Martensitic Steel

    Science.gov (United States)

    Manugula, Vijaya L.; Rajulapati, Koteswararao V.; Reddy, G. Madhusudhan; Mythili, R.; Bhanu Sankara Rao, K.

    2017-08-01

    The effects of tool rotational speed (200 and 700 rpm) on evolving microstructure during friction stir welding (FSW) of a reduced activation ferritic-martensitic steel (RAFMS) in the stir zone (SZ), thermo-mechanically affected zone (TMAZ), and heat-affected zone (HAZ) have been explored in detail. The influence of post-weld direct tempering (PWDT: 1033 K (760 °C)/ 90 minutes + air cooling) and post-weld normalizing and tempering (PWNT: 1253 K (980 °C)/30 minutes + air cooling + tempering 1033 K (760 °C)/90 minutes + air cooling) treatments on microstructure and mechanical properties has also been assessed. The base metal (BM) microstructure was tempered martensite comprising Cr-rich M23C6 on prior austenite grain and lath boundaries with intra-lath precipitation of V- and Ta-rich MC precipitates. The tool rotational speed exerted profound influence on evolving microstructure in SZ, TMAZ, and HAZ in the as-welded and post-weld heat-treated states. Very high proportion of prior austenitic grains and martensite lath boundaries in SZ and TMAZ in the as-welded state showed lack of strengthening precipitates, though very high hardness was recorded in SZ irrespective of the tool speed. Very fine-needle-like Fe3C precipitates were found at both the rotational speeds in SZ. The Fe3C was dissolved and fresh precipitation of strengthening precipitates occurred on both prior austenite grain and sub-grain boundaries in SZ during PWNT and PWDT. The post-weld direct tempering caused coarsening and coalescence of strengthening precipitates, in both matrix and grain boundary regions of TMAZ and HAZ, which led to inhomogeneous distribution of hardness across the weld joint. The PWNT heat treatment has shown fresh precipitation of M23C6 on lath and grain boundaries and very fine V-rich MC precipitates in the intragranular regions, which is very much similar to that prevailed in BM prior to FSW. Both the PWDT and PWNT treatments caused considerable reduction in the hardness of SZ

  14. Electric vehicle speed control

    Energy Technology Data Exchange (ETDEWEB)

    Krueger, W.R.; Mc Auliffe, G.N.; Schlageter, G.A.

    1987-06-23

    This patent describes an electric vehicle driven by a DC motor. The vehicle has a field winding, an electric resistance element in circuit with the field winding, a switch in the circuit operative when closed to place. The element in parallel with the field winding weakens the field and increases potential motor speed. Also are relay means for operating the switch, means to determine motor speed, computer means for determining whether the motor speed is increasing or decreasing, and means for operating the relay means to close the switch at a first speed. If the motor speed is increased, it actuates the switch at a second speed lower than the first speed but only if switch has been closed previously and motor speed is decreasing.

  15. Re-Engineering Vocational and Technical Education (VTE) for Sustainable Development in North Central Geo-Political Zone, Nigeria

    Science.gov (United States)

    Sofoluwe, Abayomi Olumade

    2013-01-01

    The purpose of the study is to re-engineer vocational and technical education for sustainable development in the North Central Geo-Political Zone in Nigeria. The research design adopted was a survey inferential type. Stratified random was used to select 36 schools out of 98 schools while 920 students out of 3680 students were sampled. The data…

  16. Competencies Required by Primary School Supervisors: Basis for a ...

    African Journals Online (AJOL)

    competencies supervisors of instruction require for a sustainable Universal Basic Education in primary schools in Anambra State. One research question and one null hypothesis guided the study. The study was carried out in Onitsha Education Zone, specifically, in all the Public Primary Schools in the three Local ...

  17. Critical Speed Control for a Fixed Blade Variable Speed Wind Turbine

    Directory of Open Access Journals (Sweden)

    Morgan Rossander

    2017-10-01

    Full Text Available A critical speed controller for avoiding a certain rotational speed is presented. The controller is useful for variable speed wind turbines with a natural frequency in the operating range. The controller has been simulated, implemented and tested on an open site 12 kW vertical axis wind turbine prototype. The controller is based on an adaptation of the optimum torque control. Two lookup tables and a simple state machine provide the control logic of the controller. The controller requires low computational resources, and no wind speed measurement is needed. The results suggest that the controller is a feasible method for critical speed control. The skipping behavior can be adjusted using only two parameters. While tested on a vertical axis wind turbine, it may be used on any variable speed turbine with the control of generator power.

  18. Impact of tropical cyclone Matmo on mixed zone of the Yellow and Bohai seas

    Science.gov (United States)

    Guo, Jie; Ji, Diansheng; Hou, Chawei; Guo, Kai; Ji, Ling

    2017-12-01

    The Bohai Sea is a low-lying semi-enclosed sea area that is linked to the Yellow Sea via the Bohai straits (mixed zone). Its off shore seabed is shallow, which makes it vulnerable to serious marine meteorological disasters associated with the northward passage of Pacifi c tropical cyclones. Analyses on data of remote sensing and buoy of the mixed zone of the Yellow and Bohai seas indicate that all the wind speed, signifi cant wave height, and salinity (SAL) increased, sea surface temperature decreased, and wind energy density changed considerably during the passage of tropical cyclone Matmo on July 25, 2014. It was found that the SAL inversion layer in the mixed zone of the Yellow and Bohai Seas was caused by the tropical cyclone. Furthermore, it was found that the tropical cyclone transported the northern Yellow Sea cold water mass (NYSCWM) into the mixed zone of the Yellow and Bohai Seas. The NYSCWM has direct infl uence on both the aquaculture and the ecological environment of the region. Therefore, further research is needed to establish the mechanism behind the formation of the SAL inversion layer in the mixed zone, and to determine the infl uence of tropical cyclones on the NYSCWM.

  19. Wear mechanism of CBN cutting tool during high-speed machining of mold steel

    International Nuclear Information System (INIS)

    Farhat, Z.N.

    2003-01-01

    Wear behavior of cubic boron nitride (CBN) cutting tool when cutting P20 tool steel was investigated. Oblique cutting tests were performed on a CNC lathe using five speeds, namely, 240, 600 and 1000 m min -1 . The CBN cutting tools were found to be superior to tungsten carbide (WC) tools. Fourfold increase in productivity and significant reduction in chipping and cratering was achieved for CBN as compared to WC. Wear, as the width of the wear land (VB), was monitored at selected time intervals; furthermore, topography of worn surfaces was performed, using a profilometer. Wear characterization of the rake and the flank surfaces as well as of the collected chips was conducted using a scanning electron microscopy (SEM), backscattered electron imaging and energy depressive X-ray (EDX). It was found that deformation in the chips occurs by localized shear deformation and the dominant wear mechanism at all speeds used was identified to be diffusive wear. At a 1000 m min -1 cutting speed, a secondary wear mechanism was identified, which is melt wear, i.e., formation of low melting point Cr and Mn compounds with the tool material and the subsequent ejection from the cutting zone

  20. A Case Study of Geologic Hazards Affecting School Buildings: Evaluating Seismic Structural Vulnerability and Landslide Hazards at Schools in Aizawl, India

    Science.gov (United States)

    Perley, M. M.; Guo, J.

    2016-12-01

    India's National School Safety Program (NSSP) aims to assess all government schools in earthquake prone regions of the country. To supplement the Mizoram State Government's recent survey of 141 government schools, we screened an additional 16 private and 4 government schools for structural vulnerabilities due to earthquakes, as well as landslide hazards, in Mizoram's capital of Aizawl. We developed a geomorphologically derived landslide susceptibility matrix, which was cross-checked with Aizawl Municipal Corporation's landslide hazard map (provided by Lettis Consultants International), to determine the geologic hazards at each school. Our research indicates that only 7% of the 22 assessed school buildings are located within low landslide hazard zones; 64% of the school buildings, with approximately 9,500 students, are located within very high or high landslide hazard zones. Rapid Visual Screening (RVS) was used to determine the structural earthquake vulnerability of each school building. RVS is an initial vulnerability assessment procedure used to inventory and rank buildings that may be hazardous during an earthquake. Our study indicates that all of the 22 assessed school buildings have a damageability rating of Grade 3 or higher on the 5-grade EMS scale, suggesting a significant vulnerability and potential for damage in buildings, ranging from widespread cracking of columns and beam column joints to collapse. Additionally, 86% of the schools we visited had reinforced concrete buildings constructed before Aizawl's building regulations were passed in 2007, which can be assumed to lack appropriate seismic reinforcement. Using our findings, we will give recommendations to the Government of Mizoram to prevent unnecessary loss of life by minimizing each school's landslide risk and ensuring schools are earthquake-resistant.

  1. The Role of Search Speed in the Contextual Cueing of Children’s Attention

    Science.gov (United States)

    Darby, Kevin; Burling, Joseph; Yoshida, Hanako

    2013-01-01

    The contextual cueing effect is a robust phenomenon in which repeated exposure to the same arrangement of random elements guides attention to relevant information by constraining search. The effect is measured using an object search task in which a target (e.g., the letter T) is located within repeated or nonrepeated visual contexts (e.g., configurations of the letter L). Decreasing response times for the repeated configurations indicates that contextual information has facilitated search. Although the effect is robust among adult participants, recent attempts to document the effect in children have yielded mixed results. We examined the effect of search speed on contextual cueing with school-aged children, comparing three types of stimuli that promote different search times in order to observe how speed modulates this effect. Reliable effects of search time were found, suggesting that visual search speed uniquely constrains the role of attention toward contextually cued information. PMID:24505167

  2. Reliability of a Computerized Neurocognitive Test in Baseline Concussion Testing of High School Athletes.

    Science.gov (United States)

    MacDonald, James; Duerson, Drew

    2015-07-01

    Baseline assessments using computerized neurocognitive tests are frequently used in the management of sport-related concussions. Such testing is often done on an annual basis in a community setting. Reliability is a fundamental test characteristic that should be established for such tests. Our study examined the test-retest reliability of a computerized neurocognitive test in high school athletes over 1 year. Repeated measures design. Two American high schools. High school athletes (N = 117) participating in American football or soccer during the 2011-2012 and 2012-2013 academic years. All study participants completed 2 baseline computerized neurocognitive tests taken 1 year apart at their respective schools. The test measures performance on 4 cognitive tasks: identification speed (Attention), detection speed (Processing Speed), one card learning accuracy (Learning), and one back speed (Working Memory). Reliability was assessed by measuring the intraclass correlation coefficient (ICC) between the repeated measures of the 4 cognitive tasks. Pearson and Spearman correlation coefficients were calculated as a secondary outcome measure. The measure for identification speed performed best (ICC = 0.672; 95% confidence interval, 0.559-0.760) and the measure for one card learning accuracy performed worst (ICC = 0.401; 95% confidence interval, 0.237-0.542). All tests had marginal or low reliability. In a population of high school athletes, computerized neurocognitive testing performed in a community setting demonstrated low to marginal test-retest reliability on baseline assessments 1 year apart. Further investigation should focus on (1) improving the reliability of individual tasks tested, (2) controlling for external factors that might affect test performance, and (3) identifying the ideal time interval to repeat baseline testing in high school athletes. Computerized neurocognitive tests are used frequently in high school athletes, often within a model of baseline testing

  3. Emotional and Behavioral Problems of Afghan Refugees and War-Zone Adolescents

    Directory of Open Access Journals (Sweden)

    Jalil Babapour-Kheiroddin

    2009-02-01

    Full Text Available "nObjective: Wars' stress and violence can have tremendous effects on children's and adolescents' health and general well being; it may result in patterns of bio-psychosocial problems. The goal of this study was to compare emotional and behavioral problems in Afghan refugees and war-zone adolescents. "n Method: One hundred and eighty high school students (90 students in the refugee group and 90 in the war-zone group in Harat were included in this research. All participants completed the Youth Self-Report (YSR. War zone and refugee adolescents were compared based on their scores on different scales of behavioral and emotional problems. "n Results: War-zone adolescents scored significantly higher on Anxious/Depression, Withdrawn, Somatic Complaints, Attention Problems, and Internalizing Problems scales than refugee adolescents. In this study, no significant difference was found between the two groups on Social Problems, Thought Problems, Delinquent Behavior, Aggressive Behavior, and Externalizing scales. "nConclusion: Findings revealed that although asylum is not an ideal condition for children's and adolescents' psychological development and prosperity, it can have a protective role in comparison with war zone's circumstances. Further investigation is needed, however, to elucidate the lack of significant differences in externalizing scales among war zone and refugee adolescents

  4. A joint probability density function of wind speed and direction for wind energy analysis

    International Nuclear Information System (INIS)

    Carta, Jose A.; Ramirez, Penelope; Bueno, Celia

    2008-01-01

    A very flexible joint probability density function of wind speed and direction is presented in this paper for use in wind energy analysis. A method that enables angular-linear distributions to be obtained with specified marginal distributions has been used for this purpose. For the marginal distribution of wind speed we use a singly truncated from below Normal-Weibull mixture distribution. The marginal distribution of wind direction comprises a finite mixture of von Mises distributions. The proposed model is applied in this paper to wind direction and wind speed hourly data recorded at several weather stations located in the Canary Islands (Spain). The suitability of the distributions is judged from the coefficient of determination R 2 . The conclusions reached are that the joint distribution proposed in this paper: (a) can represent unimodal, bimodal and bitangential wind speed frequency distributions, (b) takes into account the frequency of null winds, (c) represents the wind direction regimes in zones with several modes or prevailing wind directions, (d) takes into account the correlation between wind speeds and its directions. It can therefore be used in several tasks involved in the evaluation process of the wind resources available at a potential site. We also conclude that, in the case of the Canary Islands, the proposed model provides better fits in all the cases analysed than those obtained with the models used in the specialised literature on wind energy

  5. Problems and Prospects of Utilizing ICTs in Secondary Schools in ...

    African Journals Online (AJOL)

    Problems and Prospects of Utilizing ICTs in Secondary Schools in Owerri Education Zone, Nigeria. ... Annals of Modern Education ... ICT Education should be included in the secondary school curriculum while provision is made for necessary infrastructural support and massive training and development of skilled manpower ...

  6. Using High Speed Smartphone Cameras and Video Analysis Techniques to Teach Mechanical Wave Physics

    Science.gov (United States)

    Bonato, Jacopo; Gratton, Luigi M.; Onorato, Pasquale; Oss, Stefano

    2017-01-01

    We propose the use of smartphone-based slow-motion video analysis techniques as a valuable tool for investigating physics concepts ruling mechanical wave propagation. The simple experimental activities presented here, suitable for both high school and undergraduate students, allows one to measure, in a simple yet rigorous way, the speed of pulses…

  7. Assessment of indoor and outdoor PM species at schools and residences in a high-altitude Ecuadorian urban center.

    Science.gov (United States)

    Raysoni, Amit U; Armijos, Rodrigo X; Weigel, M Margaret; Montoya, Teresa; Eschanique, Patricia; Racines, Marcia; Li, Wen-Whai

    2016-07-01

    An air monitoring campaign to assess children's environmental exposures in schools and residences, both indoors and outdoors, was conducted in 2010 in three low-income neighborhoods in Z1 (north), Z2 (central), and Z3 (southeast) zones of Quito, Ecuador - a major urban center of 2.2 million inhabitants situated 2850 m above sea level in a narrow mountainous basin. Z1 zone, located in northern Quito, historically experienced emissions from quarries and moderate traffic. Z2 zone was influenced by heavy traffic in contrast to Z3 zone which experienced low traffic densities. Weekly averages of PM samples were collected at schools (one in each zone) and residences (Z1 = 47, Z2 = 45, and Z3 = 41) every month, over a twelve-month period at the three zones. Indoor PM2.5 concentrations ranged from 10.6 ± 4.9 μg/m(3) (Z1 school) to 29.0 ± 30.5 μg/m(3) (Z1 residences) and outdoor PM2.5 concentrations varied from 10.9 ± 3.2 μg/m(3) (Z1 school) to 14.3 ± 10.1 μg/m(3) (Z2 residences), across the three zones. The lowest values for PM10-2.5 for indoor and outdoor microenvironments were recorded at Z2 school, 5.7 ± 2.8 μg/m(3) and 7.9 ± 2.2 μg/m(3), respectively. Outdoor school PM concentrations exhibited stronger associations with corresponding indoor values making them robust proxies for indoor exposures in naturally ventilated Quito public schools. Correlation analysis between the school and residential PM size fractions and the various pollutant and meteorological parameters from central ambient monitoring (CAM) sites suggested varying degrees of temporal relationship. Strong positive correlation was observed for outdoor PM2.5 at Z2 school and its corresponding CAM site (r = 0.77) suggesting common traffic related emissions. Spatial heterogeneity in PM2.5 concentrations between CAM network and sampled sites was assessed using Coefficient of Divergence (COD) analysis. COD values were lower when CAM sites were paired with outdoor

  8. Facile Route to Vertically Aligned High-Aspect Ratio Block Copolymer Films via Dynamic Zone Annealing

    Science.gov (United States)

    Singh, Gurpreet; Kulkarni, Manish; Yager, Kevin; Smilgies, Detlef; Bucknall, David; Karim, Alamgir

    2012-02-01

    Directed assembly of block copolymers (BCP) can be used to fabricate a diversity of nanostructures useful for nanotech applications. The ability to vertically orient etchable high aspect ratio (˜30) ordered BCP domains on flexible substrates via continuous processing methods are particularly attractive for nanomanufacturing. We apply sharp dynamic cold zone annealing (CZA-S) to create etchable, and predominantly vertically oriented 30nm cylindrical domains in 1 μm thick poly(styrene-b-methylmethacrylate) films on low thermal conductivity rigid (quartz) and flexible (PDMS & Kapton) substrates. Under similar static conditions, temporally stable vertical cylinders form within a narrow zone above a critical temperature gradient. Primary ordering mechanism of CZA-S involves sweeping this vertically orienting zone created at maximum thermal gradient. An optimal speed is needed since the process competes with preferential surface wetting dynamics that favors parallel orientation. GISAXS of etched BCP films confirms internal morphology.

  9. Underwater cutting of reactor core internals by CO laser using local-dry-zone creating nozzle

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Osa (Mitsubishi Heavy Industries Ltd., Takasago, Hyogo (Japan). Takasago Research and Development Center); Sugihara, Masaaki; Miya, Kenzo

    1992-11-01

    With a view to practical application of the CO laser to underwater cutting of thick steel plates, a nozzle for creating a local dry zone on the workpiece has been developed and tested. The nozzle directed against the workpiece surface discharges a jet of air, which forms the local dry zone, bounded by a cone of high-speed water jet discharged from a concentric annular outlet. Preliminary tests were performed to optimize the nozzle shape and operating conditions. The resulting nozzle was used with a 5 kW CO laser for actual underwater cutting tests on stainless steel plates: Entirely satisfactory cutting performance was confirmed on various workpiece geometries and working positions. (author).

  10. Wind Speed Preview Measurement and Estimation for Feedforward Control of Wind Turbines

    Science.gov (United States)

    Simley, Eric J.

    Wind turbines typically rely on feedback controllers to maximize power capture in below-rated conditions and regulate rotor speed during above-rated operation. However, measurements of the approaching wind provided by Light Detection and Ranging (lidar) can be used as part of a preview-based, or feedforward, control system in order to improve rotor speed regulation and reduce structural loads. But the effectiveness of preview-based control depends on how accurately lidar can measure the wind that will interact with the turbine. In this thesis, lidar measurement error is determined using a statistical frequency-domain wind field model including wind evolution, or the change in turbulent wind speeds between the time they are measured and when they reach the turbine. Parameters of the National Renewable Energy Laboratory (NREL) 5-MW reference turbine model are used to determine measurement error for a hub-mounted circularly-scanning lidar scenario, based on commercially-available technology, designed to estimate rotor effective uniform and shear wind speed components. By combining the wind field model, lidar model, and turbine parameters, the optimal lidar scan radius and preview distance that yield the minimum mean square measurement error, as well as the resulting minimum achievable error, are found for a variety of wind conditions. With optimized scan scenarios, it is found that relatively low measurement error can be achieved, but the attainable measurement error largely depends on the wind conditions. In addition, the impact of the induction zone, the region upstream of the turbine where the approaching wind speeds are reduced, as well as turbine yaw error on measurement quality is analyzed. In order to minimize the mean square measurement error, an optimal measurement prefilter is employed, which depends on statistics of the correlation between the preview measurements and the wind that interacts with the turbine. However, because the wind speeds encountered by

  11. Measures for speed management.

    NARCIS (Netherlands)

    2009-01-01

    Measures for speed management are essential for limiting the negative effects of driving too fast and at inappropriate speeds. To begin with, safe and credible speed limits need to be determined. Dynamic and variable speed limits that take into account the current circumstances, such as weather

  12. Radiation protection zoning

    International Nuclear Information System (INIS)

    2015-01-01

    Radiation being not visible, the zoning of an area containing radioactive sources is important in terms of safety. Concerning radiation protection, 2 work zones are defined by regulations: the monitored zone and the controlled zone. The ministerial order of 15 may 2006 settles the frontier between the 2 zones in terms of radiation dose rates, the rules for access and the safety standards in both zones. Radioprotection rules and the name of the person responsible for radiation protection must be displayed. The frontier between the 2 zones must be materialized and marked with adequate equipment (specific danger signs and tapes). Both zones are submitted to selective entrance, the access for the controlled zone is limited because of the radiation risk and of the necessity of confining radioactive contamination while the limitation of the access to the monitored zone is due to radiation risk only. (A.C.)

  13. THE EFFECTS OF DIFFERENT MODELS OF SWIMMING TRAINING (DEFINED IN RELATION TO ANAEROBIC THRESHOLD ON THE INCREASE OF SWIM SPEED

    Directory of Open Access Journals (Sweden)

    Dragan Krivokapić

    2007-05-01

    Full Text Available On the sample of 32 fourth grade students of some Belgrade highs schools, who had the physical education classes carried out at the city’s swimming pools, an attempt was made to evaluate the effects of the two different programmes of swimming training in different intensity zones, defi ned relative to the anaerobic threshold. The examinees were divided into two groups out of 15 i.e. 17 participants who were not (according to statistics signifi cantly different in terms of average time and heart frequency during the 400 m swimming test and heart frequency and time measured after 50 m in the moment of reaching the anaerobic threshold. The fi rst training model consisted of swimming at the intensity level within the zone below anaerobic threshold, while the second model involved occasional swimming at a higher intensity sometimes surpassing the anaerobic threshold. The experimentalprogramme with both sub-groups lasted 8 weeks with 3 training sessions per week, 2 ‘of which we’re identical for both experimental groups, with the third one differing regarding the swimming intensity, this in the fi rst group being still in the zone below, and in the second group occasionally in the zone above the anaerobic threshold. The amount of training and the duration were the same in both programmes. The aim of the research , was to evaluate and to compare the effects of the two training models, using as the basic criteria possible changes of average time and heart frequency during the 400 m swimming test and heart frequency and time measured after 50 m in the moment of reaching the anaerobic thereshold. On the basis of the statistical analysis of the obtained data, it is possible to conclude that in both experimental groups there were statistically signifi cant changes of average values concerning all the physiological variables. Although the difference in effi ciency of applied experimental programmes is not defi ned, we can claim that both of experimental

  14. Transformational Leadership in Mozambican Primary Schools

    NARCIS (Netherlands)

    Bazo, M.

    2011-01-01

    In Mozambique the reform of the National Education System takes place through the de-centralisation, privatisation, and reorganisation of teacher training, revitalisation of Zones of Pedagogical Influences (ZIP’s), creation of community schools, creation of capacity for intervention and support at

  15. TESTING STOCK MARKETS’ INTEGRATION FROM CENTRAL AND EASTERN EUROPEAN COUNTRIES WITHIN EURO ZONE

    Directory of Open Access Journals (Sweden)

    Viorica CHIRILA

    2014-10-01

    Full Text Available Stock market integration gives the opportunity of risk diversification on international level. The main effects of this integration are the development of stock markets and economic growth. This paper analyses the integration of stock markets from Central and Eastern Europe using convergence. Beta-convergence gives us information about integration’s speed and sigma-convergence presents information about the degree of integration of stock markets from Central and Eastern Europe on the stock market of Euro Zone.

  16. Changes in speed distribution: Applying aggregated safety effect models to individual vehicle speeds.

    Science.gov (United States)

    Vadeby, Anna; Forsman, Åsa

    2017-06-01

    This study investigated the effect of applying two aggregated models (the Power model and the Exponential model) to individual vehicle speeds instead of mean speeds. This is of particular interest when the measure introduced affects different parts of the speed distribution differently. The aim was to examine how the estimated overall risk was affected when assuming the models are valid on an individual vehicle level. Speed data from two applications of speed measurements were used in the study: an evaluation of movable speed cameras and a national evaluation of new speed limits in Sweden. The results showed that when applied on individual vehicle speed level compared with aggregated level, there was essentially no difference between these for the Power model in the case of injury accidents. However, for fatalities the difference was greater, especially for roads with new cameras where those driving fastest reduced their speed the most. For the case with new speed limits, the individual approach estimated a somewhat smaller effect, reflecting that changes in the 15th percentile (P15) were somewhat larger than changes in P85 in this case. For the Exponential model there was also a clear, although small, difference between applying the model to mean speed changes and individual vehicle speed changes when speed cameras were used. This applied both for injury accidents and fatalities. There were also larger effects for the Exponential model than for the Power model, especially for injury accidents. In conclusion, applying the Power or Exponential model to individual vehicle speeds is an alternative that provides reasonable results in relation to the original Power and Exponential models, but more research is needed to clarify the shape of the individual risk curve. It is not surprising that the impact on severe traffic crashes was larger in situations where those driving fastest reduced their speed the most. Further investigations on use of the Power and/or the

  17. Using a High-Speed Camera to Measure the Speed of Sound

    Science.gov (United States)

    Hack, William Nathan; Baird, William H.

    2012-01-01

    The speed of sound is a physical property that can be measured easily in the lab. However, finding an inexpensive and intuitive way for students to determine this speed has been more involved. The introduction of affordable consumer-grade high-speed cameras (such as the Exilim EX-FC100) makes conceptually simple experiments feasible. Since the…

  18. High speed atom source

    International Nuclear Information System (INIS)

    Hoshino, Hitoshi.

    1990-01-01

    In a high speed atom source, since the speed is not identical between ions and electrons, no sufficient neutralizing effect for ionic rays due to the mixing of the ionic rays and the electron rays can be obtained failing to obtain high speed atomic rays at high density. In view of the above, a speed control means is disposed for equalizing the speed of ions forming ionic rays and the speed of electrons forming electron rays. Further, incident angle of the electron rays and/or ionic rays to a magnet or an electrode is made variable. As a result, the relative speed between the ions and the electrons to the processing direction is reduced to zero, in which the probability of association between the ions and the electrons due to the coulomb force is increased to improve the neutralizing efficiency to easily obtain fine and high density high speed electron rays. Further, by varying the incident angle, a track capable of obtaining an ideal mixing depending on the energy of the neutralized ionic rays is formed. Since the high speed electron rays has such high density, they can be irradiated easily to the minute region of the specimen. (N.H.)

  19. Measuring longitudinal wave speed in solids: two methods and a half

    International Nuclear Information System (INIS)

    Fazio, C; Guastella, I; Sperandeo-Mineo, R M; Tarantino, G

    2006-01-01

    Three methods to analyse longitudinal wave propagation in metallic rods are discussed. Two of these methods also prove to be useful for measuring the sound propagation speed. The experimental results, as well as some interpretative models built in the context of a workshop on mechanical waves at the Graduate School for Pre-Service Physics Teacher Education, Palermo University, are described. Some considerations about observed modifications in trainee teachers' attitudes to utilizing physics experiments to build pedagogical activities are discussed

  20. Fuel conditioning facility zone-to-zone transfer administrative controls

    International Nuclear Information System (INIS)

    Pope, C. L.

    2000-01-01

    The administrative controls associated with transferring containers from one criticality hazard control zone to another in the Argonne National Laboratory (ANL) Fuel Conditioning Facility (FCF) are described. FCF, located at the ANL-West site near Idaho Falls, Idaho, is used to remotely process spent sodium bonded metallic fuel for disposition. The process involves nearly forty widely varying material forms and types, over fifty specific use container types, and over thirty distinct zones where work activities occur. During 1999, over five thousand transfers from one zone to another were conducted. Limits are placed on mass, material form and type, and container types for each zone. Ml material and containers are tracked using the Mass Tracking System (MTG). The MTG uses an Oracle database and numerous applications to manage the database. The database stores information specific to the process, including material composition and mass, container identification number and mass, transfer history, and the operators involved in each transfer. The process is controlled using written procedures which specify the zone, containers, and material involved in a task. Transferring a container from one zone to another is called a zone-to-zone transfer (ZZT). ZZTs consist of four distinct phases, select, request, identify, and completion

  1. Analysis for SEER of variable speed room air conditioner in China. Paper no. IGEC-1-104

    International Nuclear Information System (INIS)

    Yitai, M.; Shengchun, L.; Lirong, M.

    2005-01-01

    In this paper, the calculation method for seasonal energy efficiency ratio (SEER) given in Standard JRA4046-1999 is analyzed and further modified. Based on temperature zone map of U.S., Japan and China and detailed weather data of eight Chinese cities in last 30 years, regional seasonal energy efficiency ratio (RSEER) and energy saving percentage of variable speed room air conditioner are analyzed and compared with various geographical regions in China. It is concluded that RSEER presents the associated effect of season, climate and geography, and therefore should be taken as an evaluation standard for room air conditioner, especially variable speed room air conditioner. Experimental measurements are conducted in the analysis to investigate the effect of energy efficiency ratio (EER) on the improvement of energy saving percentage and SEER. (author)

  2. The Effect of Schooling on Basic Cognition in Selected Nordic Countries

    Directory of Open Access Journals (Sweden)

    Bert Jonsson

    2017-11-01

    Full Text Available The present study investigated schooling effects on cognition. Cognitive data were collected as part of a research project (ProMeal that investigated school meals and measured the intake of school lunch in relation to children’s health, cognitive function, and classroom learning in four Nordic countries, among children between 10–11 years of age. It was found that Finnish pupils attending 4th grade were not, on any measure, outperformed by Norwegian and Icelandic pupils attending 5th and Swedish pupils attending 4th grade on a task measuring working memory capacity, processing speed, inhibition, and in a subsample on response- and attention control. Moreover, boys were found to perform superior to girls on tasks measuring processing speed. However, girls were found to perform better on tasks related to attention and self-control. The results are discussed in relation to the reciprocal association between cognition and schooling and whether these results reflect quality differences between schools in the four Nordic countries; most notably in comparison to Finland.

  3. Focusing on the Whole Student: An Evaluation of Massachusetts's Wraparound Zone Initiative

    Science.gov (United States)

    Gandhi, Allison Gruner; Slama, Rachel; Park, So Jung; Russo, Patrick; Winner, Kendra; Bzura, Robin; Jones, Wehmah; Williamson, Sandra

    2018-01-01

    We used a comparative interrupted time series design to examine the impact of the Massachusetts' Wraparound Zone Initiative on student achievement, attendance, retention, and suspension. This initiative was designed to create coordinated district systems that allow schools to proactively and systematically address students' nonacademic needs. The…

  4. Molecular differences in transition zone and peripheral zone prostate tumors

    Science.gov (United States)

    Sinnott, Jennifer A.; Rider, Jennifer R.; Carlsson, Jessica; Gerke, Travis; Tyekucheva, Svitlana; Penney, Kathryn L.; Sesso, Howard D.; Loda, Massimo; Fall, Katja; Stampfer, Meir J.; Mucci, Lorelei A.; Pawitan, Yudi; Andersson, Sven-Olof; Andrén, Ove

    2015-01-01

    Prostate tumors arise primarily in the peripheral zone (PZ) of the prostate, but 20–30% arise in the transition zone (TZ). Zone of origin may have prognostic value or reflect distinct molecular subtypes; however, it can be difficult to determine in practice. Using whole-genome gene expression, we built a signature of zone using normal tissue from five individuals and found that it successfully classified nine tumors of known zone. Hypothesizing that this signature captures tumor zone of origin, we assessed its relationship with clinical factors among 369 tumors of unknown zone from radical prostatectomies (RPs) and found that tumors that molecularly resembled TZ tumors showed lower mortality (P = 0.09) that was explained by lower Gleason scores (P = 0.009). We further applied the signature to an earlier study of 88 RP and 333 transurethral resection of the prostate (TURP) tumor samples, also of unknown zone, with gene expression on ~6000 genes. We had observed previously substantial expression differences between RP and TURP specimens, and hypothesized that this might be because RPs capture primarily PZ tumors, whereas TURPs capture more TZ tumors. Our signature distinguished these two groups, with an area under the receiver operating characteristic curve of 87% (P zones. Zone of origin may be important to consider in prostate tumor biomarker research. PMID:25870172

  5. Overview of Game Effect on Dynamics of Speed Development in Girls of Primary School Age

    Directory of Open Access Journals (Sweden)

    С. І. Марченко

    2016-12-01

    Full Text Available The reserch objective is to analyze the effect of game means on the dynamics of speed abilities development in girls of the second-fourth grade. Materials and Methods. The participants in the experiment were 104 female pupils of the second grade (n=32, third grade (n=32, and fourth grade (n=40.  Research Methods: theoretical analysis and collation of scientific and methodological literature, method of control testing, pedagogical experiment, methods of mathematical statistics. Results. The study proves the necessity to use game exercises that are rationally balanced in terms of orientation, power and scope with regard to the individual constitutional peculiarities of children in order to achieve the best pedagogical effect in the development of speed abilities. The games performed with the highest swiftness contribute to the development of speed. These exercises require the best efforts, which is why their duration must not exceed 5—10 seconds, the rest intervals must be relatively large — from 40 to 60 seconds. The rest time and load time must not be constant. Conclusions. Selective and directed development of motor abilities requires taking into account the duration and pace (intensity of the performance of the physical exercises.

  6. Epidemiology of intestinal helminthiasis among school children with emphasis on Schistosoma mansoni infection in Wolaita zone, Southern Ethiopia.

    Science.gov (United States)

    Alemayehu, Bereket; Tomass, Zewdneh; Wadilo, Fiseha; Leja, Dawit; Liang, Song; Erko, Berhanu

    2017-06-20

    Intestinal helminth infections are major parasitic diseases causing public health problems in Ethiopia. Although the epidemiology of these infections are well documented in Ethiopia, new transmission foci for schistosomiasis are being reported in different parts of the country. The objective of this study was to assess the prevalence of Schistosoma mansoni and other intestinal helminth infections among school children and determine the endemicity of schistosomiasis in Wolaita Zone, southern Ethiopia. Cross-sectional parasitological and malacological surveys were conducted by collecting stool samples for microscopic examination and snails for intermediate host identification. Stool samples were collected from 503 children and processed for microscopic examination using Kato-Katz and formalin-ether concentration methods. Snails collected from aquatic environments in the study area were identified to species level and Biomphalaria pfeifferi snails, the intermediate host of S. mansoni,, were individually exposed to artificial light in order to induce cercariae shedding. Cercariae shed from snails were used to infect laboratory-bred Swiss albino mice in order to identify the schistosome to species level. The overall prevalence of intestinal helminth infections was 72.2% among school children. S. mansoni infection prevalence was 58.6%. The prevalence and intensity of S. mansoni infections varied among schools and sex of children. Swimming was the only factor reported to be significantly associated with S. mansoni infection (AOR = 2.954, 95% CI:1.962-4.449). Other intestinal helminth species identified were hookworms (27.6%), Ascaris lumbricoides (8.7%), E. vermicularis (2.8%), Taenia species (2.6%), T. trichiura (1.2%) and H. nana (0.6%). Only B. pfeifferi snails collected from streams shed schistosome cercariae and 792 adult S. mansoni worms were harvested from mice exposed to cercariae shed from B. pfeifferi on the 6th week post-exposure. The present study found high

  7. Level of health literacy and factors associated with it among school teachers in an education zone in Colombo, Sri Lanka

    Directory of Open Access Journals (Sweden)

    H. M. B. H. Denuwara

    2017-07-01

    Full Text Available Abstract Background Health literacy refers to people's competencies to access, understand, judge and apply health information in healthcare, disease prevention and health promotion. This study aimed to describe the level of health literacy and the factors associated with it among school teachers in an Education Zone in Colombo, Sri Lanka. Methods A cross-sectional study among 520 teachers measured health literacy using the selfadministered, culturally adapted Sinhalese translation of Health Literacy Survey-European Union (HLS-EU. Health literacy assessment was based on self-reported competencies to access, understand, judge and apply health information in the domains of disease prevention, healthcare and health promotion. Based on a score, respondents were divided into four levels of health literacy as 'inadequate', 'problematic', 'sufficient' and 'excellent' as well as into two levels as 'limited' and 'adequate'. Factors associated with 'limited' health literacy was determined by using univariate analysis and assessing their associations using chi square test. Multivariate analysis was also done using multiple logistic regression to determine factors associated with limited health literacy controlled for confounding effects. A p value of 0.05 determined the significance. Results The response rate was 96.5%. Mean age was 43years (SD = +9.75, 81.7% (n = 410 were females and 66.1% (n = 332 were graduates. Only 3.6% (n = 18 taught the subject health while 18.3% (n = 92 taught science. 'Limited' health literacy was found in 32.5% (95% CI 28.4%–36.6% while 67.5% (95% CI 63.4%–71.6%, 61.2% (95% CI 56.9%-65.5% and 6.4% (95% CI 4.3%–8.5% showed 'adequate', 'sufficient' and 'excellent' levels, respectively. 'Problematic' and 'inadequate' health literacy were 31.5% (95% CI 27.4%-35.6% and 1% (95% CI 0.1%–1.9%. Univariate analysis showed not being a member of health club/welfare group (p = 0.002, having not done any special course on health (p = 0

  8. Level of health literacy and factors associated with it among school teachers in an education zone in Colombo, Sri Lanka.

    Science.gov (United States)

    Denuwara, H M B H; Gunawardena, Nalika Sepali

    2017-07-06

    Health literacy refers to people's competencies to access, understand, judge and apply health information in healthcare, disease prevention and health promotion. This study aimed to describe the level of health literacy and the factors associated with it among school teachers in an Education Zone in Colombo, Sri Lanka. A cross-sectional study among 520 teachers measured health literacy using the selfadministered, culturally adapted Sinhalese translation of Health Literacy Survey-European Union (HLS-EU). Health literacy assessment was based on self-reported competencies to access, understand, judge and apply health information in the domains of disease prevention, healthcare and health promotion. Based on a score, respondents were divided into four levels of health literacy as 'inadequate', 'problematic', 'sufficient' and 'excellent' as well as into two levels as 'limited' and 'adequate'. Factors associated with 'limited' health literacy was determined by using univariate analysis and assessing their associations using chi square test. Multivariate analysis was also done using multiple logistic regression to determine factors associated with limited health literacy controlled for confounding effects. A p value of 0.05 determined the significance. The response rate was 96.5%. Mean age was 43years (SD = +9.75), 81.7% (n = 410) were females and 66.1% (n = 332) were graduates. Only 3.6% (n = 18) taught the subject health while 18.3% (n = 92) taught science. 'Limited' health literacy was found in 32.5% (95% CI 28.4%-36.6%) while 67.5% (95% CI 63.4%-71.6%), 61.2% (95% CI 56.9%-65.5%) and 6.4% (95% CI 4.3%-8.5%) showed 'adequate', 'sufficient' and 'excellent' levels, respectively. 'Problematic' and 'inadequate' health literacy were 31.5% (95% CI 27.4%-35.6%) and 1% (95% CI 0.1%-1.9%). Univariate analysis showed not being a member of health club/welfare group (p = 0.002), having not done any special course on health (p = 0.009), not getting an opportunity to participate

  9. Distribution of Subsurface Flexure zone caused by Uemachi Fault, Japan and its activity

    Science.gov (United States)

    Kitada, N.; Inoue, N.; Takemura, K.; Ito, H.; Mitamura, M.

    2012-12-01

    In Osaka, Uemachi Fault is one of the famous active faults. It across the center of Osaka and lies in N-S direction mainly and is more than 40 km in length. The faults bound sedimentary basins, where thick sedimentary deposits of the Pliocene-Quaternary Osaka Group have accumulated. The deposits consist primarily of sand and marine and non-marine clay, and the clay layers are key markers for the interpretation of glacial and interglacial cycles. In this study, we estimate the width of the flexure zone using a geotechnical borehole database. GI database collects more than 40,000 boreholes and includes both geological information and soil properties around Osaka by the Geo-database Information Committee of Kansai Area. Our results indicate that the deformation associated with the flexure zone is distributed primarily along the splay fault (NE-SW) and not along the main fault, suggesting that the splay fault might be the primary fault at present. We first examined the borehole data along the seismic reflection line and then considered the surrounding area. An Upper Pleistocene marine clay (Ma12) is a good indicator of the flexure zone. We constructed many cross sections in and around the fault zone and classified the deformation form into three categories around the flexure zone. The results of this study allowed us to map the distribution of folding in a zone in the west of the Osaka area. Folding can be classified into three types: (1) Ma12 folding, (2) Ma12 folding that does not continue toward the hanging wall, and (3) folding or displacement of old marine clay. These folding zone trends are N-W strike however these trace are serpentine. These folding zone information are not in worth to estimate the source fault, however these zone will be more serious damaged when the earthquake occurred. Our result agrees well with the average displacement speed of about 0.4 m/ka that was derived by the Headquarters for Earthquake Research Promotion of the Ministry of Education

  10. The effects of Nordic school meals on concentration and school performance in 8- to 11-year-old children in the OPUS School Meal Study: a cluster-randomised, controlled, cross-over trial

    DEFF Research Database (Denmark)

    Sørensen, Louise B.; Dyssegaard, Camilla B.; Damsgaard, Camilla T.

    2015-01-01

    . The OPUS (Optimal well-being, development and health for Danish children through a healthy New Nordic Diet) School Meal Study was a cluster-randomised, controlled, cross-over trial comparing a healthy school meal programme with the usual packed lunch from home (control) each for 3 months (NCT 01457794......It is widely assumed that nutrition can improve school performance in children; however, evidence remains limited and inconclusive. In the present study, we investigated whether serving healthy school meals influenced concentration and school performance of 8- to 11-year-old Danish children...... than reading speed. There was no effect on overall math performance or outcomes from the LRS. In conclusion, school meals did not affect CP, but improved reading performance, which is a complex cognitive activity that involves inference, and increased errors related to impulsivity and inattention...

  11. Effect of priming cooperation or individualism on a collective and interdependent task: changeover speed in the 4 x 100-meter relay race.

    Science.gov (United States)

    Bry, Clémentine; Meyer, Thierry; Oberlé, Dominique; Gherson, Thibault

    2009-06-01

    Priming effects of cooperation vs. individualism were investigated on changeover speed within a 4 x 100-m relay race. Ten teams of four adult beginner athletes ran two relays, a pretest race and an experimental race 3 weeks later. Just before the experimental race, athletes were primed with either cooperation or individualism through a scrambled-sentence task. Comparing to the pretest performance, cooperation priming improved baton speed in the exchange zone (+30 cm/s). Individualism priming did not impair changeover performance. The boundary conditions of priming effects applied to collective and interdependent tasks are discussed within the implicit coordination framework.

  12. Identification and observability problems of the induction motor for sensor-less industrial speed variation; Problemes d'identification et d'observabilite du moteur a induction pour la variation de vitesse industrielle sans capteur

    Energy Technology Data Exchange (ETDEWEB)

    Malrait, F.

    2001-02-15

    In order to improve the efficiency of a speed variator or to make autonomous the control of induction motors without mechanical sensor, the speed variator must integrate with a good precision the parameters of the motor to which it is connected. In this work, an identification phase when the motor is off is proposed. This raises the problem of the modeling of the induction motor and of the power stage (saturation model, voltage drop in the power stage components) in an unusual operation zone for a speed variator. The knowledge of the off-line electrical parameters is thus not sufficient. During normal operation, the thermal drift of resistors leads to a parametric error which can create blocking problems in the low sped domain or which can significantly lower the efficiency. The low-speed zone has been analyzed. This zone contains some intrinsic properties of the induction motor: instability, non-observability (first order). The synthesis of an observer of the induction motor is proposed which is based on the linearization of the system around a trajectory. A construction method has been developed to generate a non-singular observer for a system changing with time and having observability singularities. This result comes from this study on systems having controllability singularities for linear systems with time-variable coefficients. An exogenous loop is explicitly proposed which allows to transform the original system into integrator chains without singularities. (J.S.)

  13. Of floating-zone uranium; Sur l'uranium de zone flottante

    Energy Technology Data Exchange (ETDEWEB)

    Clottes, G [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1965-01-01

    The floating zone method has been chosen in order to purify uranium. The various parameters occurring in this purification technique, have been studied theoretically and technologically. The speed that proves to be the most efficient is 0,7 cm/h, the direction can only upwards, and the fusion must take place under pressure of 10{sup -7} Torr or so. Besides such problems concerning purification, the study of the floating zone stability led us to define a field touching the size and diameter of uranium drops, which, on the one hand coincides with Heywang's conditions and, on the other hand, is compatible with a fusion in the core of the bar. Such field shows that the floating zone can easily apply to bars whose diameter is included between 5 and 10 mm, and that it cannot work out when the diameter exceeds 21 mm. The apparatus, consisting in a means of heating by electronic bombardment under ultra-vacuum is conditioned by the various parameters that have been studied. As the analysis results were insufficient, the uranium thus dealt with has been characterized by metallurgic and physical tests: micrographic tests, measures of microhardness, measures of electric resistivity at a low temperature, have shown a definite purification at the bar-head; these results have been confirmed by the lowering at 270 C of the temperature of recrystallization together with the definite tendency of the refined metal to polygonize. The measures of electric resistivity constitute an easy and quantitative way of figuring out the metal purity. The influence of an impurity on the electric resistivity of uranium has been studied by U-Au alloys with a weak concentration of gold. The two important following points are brought out be these experiences: 1 - the measure of electric resistivity should be worked out on anneal bars in {gamma} phase and cooled. 2 - Gold has a very strong influence on uranium; the value 500 {mu}{omega}cm per cent of gold enabled us to give a total concentration of 20

  14. Estimation of Unsaturated Zone Traveltimes for Rainier Mesa and Shoshone Mountain, Nevada Test Site, Nevada, Using a Source-Responsive Preferential-Flow Model

    Science.gov (United States)

    Ebel, Brian A.; Nimmo, John R.

    2009-01-01

    Traveltimes for contaminant transport by water from a point in the unsaturated zone to the saturated zone are a concern at Rainier Mesa and Shoshone Mountain in the Nevada Test Site, Nevada. Where nuclear tests were conducted in the unsaturated zone, contaminants must traverse hundreds of meters of variably saturated rock before they enter the saturated zone in the carbonate rock, where the regional groundwater system has the potential to carry them substantial distances to a location of concern. The unsaturated-zone portion of the contaminant transport path may cause a significant delay, in addition to the time required to travel within the saturated zone, and thus may be important in the overall evaluation of the potential hazard from contamination. Downward contaminant transport through the unsaturated zone occurs through various processes and pathways; this can lead to a broad distribution of contaminant traveltimes, including exceedingly slow and unexpectedly fast extremes. Though the bulk of mobile contaminant arrives between the time-scale end members, the fastest contaminant transport speed, in other words the speed determined by the combination of possible processes and pathways that would bring a measureable quantity of contaminant to the aquifer in the shortest time, carries particular regulatory significance because of its relevance in formulating the most conservative hazard-prevention scenarios. Unsaturated-zone flow is usually modeled as a diffusive process responding to gravity and pressure gradients as mediated by the unsaturated hydraulic properties of the materials traversed. The mathematical formulation of the diffuse-flow concept is known as Richards' equation, which when coupled to a solute transport equation, such as the advection-dispersion equation, provides a framework to simulate contaminant migration in the unsaturated zone. In recent decades awareness has increased that much fluid flow and contaminant transport within the unsaturated

  15. Estimation of unsaturated zone traveltimes for Rainier Mesa and Shoshone Mountain, Nevada Test Site, Nevada, using a source-responsive preferential-flow model

    Energy Technology Data Exchange (ETDEWEB)

    Brian A. Ebel; John R. Nimmo

    2009-09-11

    Traveltimes for contaminant transport by water from a point in the unsaturated zone to the saturated zone are a concern at Rainier Mesa and Shoshone Mountain in the Nevada Test Site, Nevada. Where nuclear tests were conducted in the unsaturated zone, contaminants must traverse hundreds of meters of variably saturated rock before they enter the saturated zone in the carbonate rock, where the regional groundwater system has the potential to carry them substantial distances to a location of concern. The unsaturated-zone portion of the contaminant transport path may cause a significant delay, in addition to the time required to travel within the saturated zone, and thus may be important in the overall evaluation of the potential hazard from contamination. Downward contaminant transport through the unsaturated zone occurs through various processes and pathways; this can lead to a broad distribution of contaminant traveltimes, including exceedingly slow and unexpectedly fast extremes. Though the bulk of mobile contaminant arrives between the time-scale end members, the fastest contaminant transport speed, in other words the speed determined by the combination of possible processes and pathways that would bring a measureable quantity of contaminant to the aquifer in the shortest time, carries particular regulatory significance because of its relevance in formulating the most conservative hazard-prevention scenarios. Unsaturated-zone flow is usually modeled as a diffusive process responding to gravity and pressure gradients as mediated by the unsaturated hydraulic properties of the materials traversed. The mathematical formulation of the diffuse-flow concept is known as Richards' equation, which when coupled to a solute transport equation, such as the advection-dispersion equation, provides a framework to simulate contaminant migration in the unsaturated zone. In recent decades awareness has increased that much fluid flow and contaminant transport within the

  16. Ship speed optimization: Concepts, models and combined speed-routing scenarios

    DEFF Research Database (Denmark)

    Psaraftis, Harilaos N.; Kontovas, Christos A.

    2014-01-01

    The purpose of this paper is to clarify some important issues as regards ship speed optimization at the operational level and develop models that optimize ship speed for a spectrum of routing scenarios in a single ship setting. The paper's main contribution is the incorporation of those fundament...... parameters and other considerations that weigh heavily in a ship owner's or charterer's speed decision and in his routing decision, wherever relevant. Various examples are given so as to illustrate the properties of the optimal solution and the various trade-offs that are involved....

  17. Analysis of the Corrosion Behavior of an A-TIG Welded SS 409 Weld Fusion Zone

    Science.gov (United States)

    Vidyarthy, R. S.; Dwivedi, D. K.

    2017-11-01

    AISI 409 (SS 409) ferritic stainless steel is generally used as the thick gauge section in freight train wagons, in ocean containers, and in sugar refinery equipment. Activating the flux tungsten inert gas (A-TIG) welding process can reduce the welding cost during fabrication of thick sections. However, corrosion behavior of the A-TIG weld fusion zone is a prime concern for this type of steel. In the present work, the effect of the A-TIG welding process parameters on the corrosion behavior of a weld fusion zone made of 8-mm-thick AISI 409 ferritic stainless-steel plate has been analyzed. Potentiodynamic polarization tests were performed to evaluate the corrosion behavior. The maximum corrosion potential ( E corr) was shown by the weld made using a welding current of 215 A, a welding speed of 95 mm/min, and a flux coating density of 0.81 mg/cm2. The minimum E corr was observed in the weld made using a welding current of 190 A, a welding speed of 120 mm/min, and a flux coating density of 1.40 mg/cm2. The current study also presents the inclusive microstructure-corrosion property relationships using the collective techniques of scanning electron microscopy, energy-dispersive x-ray spectroscopy, and x-ray diffraction.

  18. Teaching high-speed photography and photo-instrumentation

    Science.gov (United States)

    Davidhazy, Andrew

    2005-03-01

    As the tools available to the high speed photographer have become more powerful the underlying technology has increased in complexity and often is beyond the reach of most practitioners in terms of in-the-field troubleshooting or adaptation and this specialization has also driven many systems beyond the reach of high school, community college and undergraduate, non-research funded, universities. In spite of this and with the belief that fundamental techniques, reasoning and approaches have not changed much over the years, several courses in photo-instrumentation at the Imaging and Photographic Technology program at the Rochester Institute of Technology present to a couple dozen undergraduate students a year the principles associated with a various imaging systems and techniques for visualization and data analysis of high speed or "invisible" phenomena. This paper reviews the objectives and philosophy of these courses in the context of a total imaging technology education. It describes and illustrates current topics included in the program. In brief, calibration and time measurement concepts, instantaneous and repetitive time sampling equipment, various visualization technologies, strip and streak cameras and applications using film and improvised digital recorders, basic velocimetry techniques including sensitometric velocimetry and synchro-ballistic photography plus other related techniques are introduced to undergraduate students.

  19. WorkZoneQ user guide for two-lane freeway work zones.

    Science.gov (United States)

    2013-06-01

    WorkZoneQ was developed in Visual Basic for Applications (VBA) to implement the results of the previous study, : Queue and Users Costs in Highway Work Zones. This report contains the WorkZoneQ user guide. WorkZoneQ : consists of eight Excel ...

  20. Delineation of marine ecosystem zones in the northern Arabian Sea during winter

    Directory of Open Access Journals (Sweden)

    S. Shalin

    2018-03-01

    Full Text Available The spatial and temporal variability of marine autotrophic abundance, expressed as chlorophyll concentration, is monitored from space and used to delineate the surface signature of marine ecosystem zones with distinct optical characteristics. An objective zoning method is presented and applied to satellite-derived Chlorophyll a (Chl a data from the northern Arabian Sea (50–75° E and 15–30° N during the winter months (November–March. Principal component analysis (PCA and cluster analysis (CA were used to statistically delineate the Chl a into zones with similar surface distribution patterns and temporal variability. The PCA identifies principal components of variability and the CA splits these into zones based on similar characteristics. Based on the temporal variability of the Chl a pattern within the study area, the statistical clustering revealed six distinct ecological zones. The obtained zones are related to the Longhurst provinces to evaluate how these compared to established ecological provinces. The Chl a variability within each zone was then compared with the variability of oceanic and atmospheric properties viz. mixed-layer depth (MLD, wind speed, sea-surface temperature (SST, photosynthetically active radiation (PAR, nitrate and dust optical thickness (DOT as an indication of atmospheric input of iron to the ocean. The analysis showed that in all zones, peak values of Chl a coincided with low SST and deep MLD. The rate of decrease in SST and the deepening of MLD are observed to trigger the algae bloom events in the first four zones. Lagged cross-correlation analysis shows that peak Chl a follows peak MLD and SST minima. The MLD time lag is shorter than the SST lag by 8 days, indicating that the cool surface conditions might have enhanced mixing, leading to increased primary production in the study area. An analysis of monthly climatological nitrate values showed increased concentrations associated with the deepening

  1. Delineation of marine ecosystem zones in the northern Arabian Sea during winter

    Science.gov (United States)

    Shalin, Saleem; Samuelsen, Annette; Korosov, Anton; Menon, Nandini; Backeberg, Björn C.; Pettersson, Lasse H.

    2018-03-01

    The spatial and temporal variability of marine autotrophic abundance, expressed as chlorophyll concentration, is monitored from space and used to delineate the surface signature of marine ecosystem zones with distinct optical characteristics. An objective zoning method is presented and applied to satellite-derived Chlorophyll a (Chl a) data from the northern Arabian Sea (50-75° E and 15-30° N) during the winter months (November-March). Principal component analysis (PCA) and cluster analysis (CA) were used to statistically delineate the Chl a into zones with similar surface distribution patterns and temporal variability. The PCA identifies principal components of variability and the CA splits these into zones based on similar characteristics. Based on the temporal variability of the Chl a pattern within the study area, the statistical clustering revealed six distinct ecological zones. The obtained zones are related to the Longhurst provinces to evaluate how these compared to established ecological provinces. The Chl a variability within each zone was then compared with the variability of oceanic and atmospheric properties viz. mixed-layer depth (MLD), wind speed, sea-surface temperature (SST), photosynthetically active radiation (PAR), nitrate and dust optical thickness (DOT) as an indication of atmospheric input of iron to the ocean. The analysis showed that in all zones, peak values of Chl a coincided with low SST and deep MLD. The rate of decrease in SST and the deepening of MLD are observed to trigger the algae bloom events in the first four zones. Lagged cross-correlation analysis shows that peak Chl a follows peak MLD and SST minima. The MLD time lag is shorter than the SST lag by 8 days, indicating that the cool surface conditions might have enhanced mixing, leading to increased primary production in the study area. An analysis of monthly climatological nitrate values showed increased concentrations associated with the deepening of the mixed layer. The

  2. ZoneLib

    DEFF Research Database (Denmark)

    Jessen, Jan Jacob; Schiøler, Henrik

    2006-01-01

    We present a dynamic model for climate in a livestock building divided into a number of zones, and a corresponding modular Simulink library (ZoneLib). While most literature in this area consider air flow as a control parameter we show how to model climate dynamics using actual control signals...... development of ZoneLib....

  3. Effects of phonological awareness and naming speed on mathematics skills in children with mild intellectual disabilities.

    Science.gov (United States)

    Foster, Matthew E; Sevcik, Rose A; Romski, Maryann; Morris, Robin D

    2015-01-01

    Both phonological awareness (PA) and naming speed have been identified as two skills related to the development of mathematics skills for children with and without learning disabilities. The purpose of the present study was to investigate the relationships between PA and colour naming speed for 265 elementary school students with mild intellectual disabilities (MID). Participants were assessed using the Comprehensive Test of Phonological Processes and the KeyMath Revised Diagnostic Inventory of Essential Mathematics. Hierarchical regression analyses accounting for the effects of age indicated that children with MID rely on both PA and naming speed when solving mathematics problems, although PA was the more robust indicator of the two. As a whole, these results suggest that children with intellectual disabilities evidence the same types of reading and math relationships as shown for other populations of children.

  4. SUSTENABLE DEVELOPMENT OF THE ROMANIAN ECONOMY BY ADOPTING THE CHINESE MODEL OF SPECIAL ECONOMIC ZONES

    Directory of Open Access Journals (Sweden)

    NEGREA Adrian

    2011-12-01

    Full Text Available The architecture of the Chinese economy began to take shape in the late 1980's, because of the new reforms that the Chinese Communist Party started to take. With the death of Mao Zedong in 1976, the Chinese leadership is taken by Deng Xiaoping, who stated a blitz course in capitalism. The new president encouraged foreign direct investments by creating special economic zones near the costal cities, were foreign companies obtained several tax brakes and other incentives, only to invest in those regions. With the help of statistical data from WTO, IMF, and the World Bank, the current paper analyzes the impact of these special economic zones on the Chinese economy, raging from mutations in the labor market and economic sectors structure and their evolution in the formation of the GDP, FDI inflows, and last but not least external trade and current account situation. On the other hand, the paper tries to make a connection with Romania, computing and predicting, based on the Chinese figures, the way in which the Romanian economy, by creating four economic zones within the counties of Satu Mare, Bihor, Arad, and Constanta, will be able to experience the same growth. The first three counties have been piked up based on their proximity to the Schengen area, and/or on their infrastructure, plain terrain, and a qualified and skilled labour force. Constanta, the only one that resembles with its Chinese counterparts, has been considered because of its capabilities of shipping products right away as they are manufactured. The results would decrease the disparity that exists in revenue levels across Romania, Bucharest leading the group way ahead of the other counties. Foreign direct investments in those areas will attract more others made by the local authorities in the infrastructure (schools, universities, roads, airports, high speed railways. This development will have a direct impact on the current account of the Romania's balance sheet of payments, while

  5. Empowerment Zones and Enterprise Districts - MDC_EnterpriseZone

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Polygon feature class of Miami Dade County Enterprise Zones. Enterprise Zones are special areas in the county where certain incentives from the State are available...

  6. What Are You Measuring? Dimensionality and Reliability Analysis of Ability and Speed in Medical School Didactic Examinations.

    Science.gov (United States)

    Thompson, James J

    2016-01-01

    Summative didactic evaluation often involves multiple choice questions which are then aggregated into exam scores, course scores, and cumulative grade point averages. To be valid, each of these levels should have some relationship to the topic tested (dimensionality) and be sufficiently reproducible between persons (reliability) to justify student ranking. Evaluation of dimensionality is difficult and is complicated by the classic observation that didactic performance involves a generalized component (g) in addition to subtest specific factors. In this work, 183 students were analyzed over two academic years in 13 courses with 44 exams and 3352 questions for both accuracy and speed. Reliability at all levels was good (>0.95). Assessed by bifactor analysis, g effects dominated most levels resulting in essential unidimensionality. Effect sizes on predicted accuracy and speed due to nesting in exams and courses was small. There was little relationship between person ability and person speed. Thus, the hierarchical grading system appears warrented because of its g-dependence.

  7. Uniaxial alignment of triisopropylsilylethynyl pentacene via zone-casting technique.

    Science.gov (United States)

    Su, Yajun; Gao, Xiang; Liu, Jiangang; Xing, Rubo; Han, Yanchun

    2013-09-14

    Uniaxially aligned triisopropylsilylethynyl pentacene (TIPS-pentacene) crystals over a large area were fabricated using zone-casting technique. The array of TIPS-pentacene displayed a high orientation degree with a dichroic ratio (DR) of 0.80. The crystals were arranged with c axis perpendicular to the substrate and the long axis of the ribbon corresponded to the a axis of TIPS-pentacene. The properties of the solutions and the processing parameters were shown to influence the formation of the oriented TIPS-pentacene crystalline array. Solvent with a low boiling point (such as chloroform) favoured the orientation of the ribbon-like crystals. The concentration of the solution should be appropriate, ensuring the crystallization velocity of TIPS-pentacene matching with the receding of the meniscus. Besides, we proved that the casting speed should be large enough to induce a sufficient concentration gradient. The orientation mechanism of TIPS-pentacene was attributed to a synergy of the ordered nuclei and a match between the crystallization velocity and the casting speed. Field effect transistors (FETs) based on the oriented TIPS-pentacene crystalline array showed a mobility of 0.67 cm(2) V(-1) s(-1).

  8. Computer ray tracing speeds.

    Science.gov (United States)

    Robb, P; Pawlowski, B

    1990-05-01

    The results of measuring the ray trace speed and compilation speed of thirty-nine computers in fifty-seven configurations, ranging from personal computers to super computers, are described. A correlation of ray trace speed has been made with the LINPACK benchmark which allows the ray trace speed to be estimated using LINPACK performance data. The results indicate that the latest generation of workstations, using CPUs based on RISC (Reduced Instruction Set Computer) technology, are as fast or faster than mainframe computers in compute-bound situations.

  9. Spectroscopical plasma diagnostics for the procedure optimization in laser-beam high-speed cutting; Spektroskopische Plasmadiagnostik zur Verfahrensoptimierung beim Laserstrahl-Hochgeschwindigkeitsschneiden

    Energy Technology Data Exchange (ETDEWEB)

    Nate, M.

    2001-07-01

    In the present thesis the laser-induced plasma typical for the high- speed cutting process was studied in the region of the interaction zone. For this especially the absorption properties of the plasma for the incident laser radiation and their correlation with the maximally reachable cutting speeds. For this with methods of the spectroscopic plasma diagnostics the influence of different process parameters on the quantities characterizing the plasma, electron density and temperature, was determined. On the base of these values in the framework of an equilibrium model the densities of all particles contained in the plasma were determined. With these values the plasma absorption coefficient was subsequently calculated and the laser radiation absorbed in the plasma estimated.

  10. An Investigation to Determine if Higher Speeds are Obtained with the Diamond Jubilee Gregg Shorthand Method.

    Science.gov (United States)

    Starbuck, Ethel

    The purpose of the study was to determine whether higher shorthand speeds were achieved by high school students in a 1-year shorthand course through the use of Simplified Gregg Shorthand or through the use of Diamond Jubilee (DJ) Gregg Shorthand. The control group consisted of 75 students enrolled in Simplified Shorthand during the years…

  11. Walking speed-related changes in stride time variability: effects of decreased speed

    Directory of Open Access Journals (Sweden)

    Dubost Veronique

    2009-08-01

    Full Text Available Abstract Background Conflicting results have been reported regarding the relationship between stride time variability (STV and walking speed. While some studies failed to establish any relationship, others reported either a linear or a non-linear relationship. We therefore sought to determine the extent to which decrease in self-selected walking speed influenced STV among healthy young adults. Methods The mean value, the standard deviation and the coefficient of variation of stride time, as well as the mean value of stride velocity were recorded while steady-state walking using the GAITRite® system in 29 healthy young adults who walked consecutively at 88%, 79%, 71%, 64%, 58%, 53%, 46% and 39% of their preferred walking speed. Results The decrease in stride velocity increased significantly mean values, SD and CoV of stride time (p Conclusion The results support the assumption that gait variability increases while walking speed decreases and, thus, gait might be more unstable when healthy subjects walk slower compared with their preferred walking speed. Furthermore, these results highlight that a decrease in walking speed can be a potential confounder while evaluating STV.

  12. Psychosocial Variables Associated with Body Composition and Cardiorespiratory Fitness in Middle School Students

    Science.gov (United States)

    Greenleaf, Christy A.; Petrie, Trent A.; Martin, Scott B.

    2010-01-01

    This study examined the associations among self-esteem, depression, physical self-concept, and body satisfaction among 1,022 middle school students who were in the FITNESSGRAM[R] Healthy Fitness Zone[TM] (HFZ) compared to those in the Needs Improvement Zone (NIZ) for body composition and cardiorespiratory fitness. After controlling for…

  13. Slip Zone versus Damage Zone Micromechanics, Arima-Takasuki Tectonic Line, Japan

    Science.gov (United States)

    White, J. C.; Lin, A.

    2017-12-01

    The Arima-Takasuki Tectonic Line (ATTL) of southern Honshu, Japan is defined by historically active faults and multiple splays producing M7 earthquakes. The damage zone of the ATTL comprises a broad zone of crushed, comminuted and pulverized granite/rhyolite1,2containing cm-scale slip zones and highly comminuted injection veins. In this presentation, prior work on the ATTL fault rocks is extending to include microstructural characterization by transmission electron microscopy (TEM) from recent trenching of the primary slip zone, as well as secondary slip zones. This is necessary to adequately characterize the extremely fine-grained material (typically less than 1mm) in both damage and core zones. Damage zone material exhibits generally random textures3 whereas slip zones are macroscopically foliated, and compositionally layered, notwithstanding a fairly homogeneous protolith. The latter reflects fluid-rock interaction during both coseismic and interseismic periods. The slip zones are microstructurally heterogeneous at all scales, comprising not only cataclasites and phyllosilicate (clay)-rich gouge zones, but Fe/Mn pellets or clasts that are contained within gouge. These structures appear to have rolled and would suggest rapid recrystallization and/or growth. A central question related to earthquake recurrence along existing faults is the nature of the gouge. In both near-surface exposures and ongoing drilling at depth, "plastic" or "viscous" gouge zones comprise ultra-fine-grained clay-siliciclastic particles that would not necessarily respond in a simple frictional manner. Depending on whether the plastic nature of these slip zones develops during or after slip, subsequent focusing of slip within them could be complicated. 1 Mitchell, T.A., Ben-Zion, Y., Shimamoto, T., 2011. Ear. Planet. Sci. Lett. 308, 284-297. 2 Lin, A., Yamashita, K, Tanaka, M. J., 2013. Struc. Geol. 48, 3-13. 3 White, J.C., Lin, A. 2016. Proc. AGU Fall Mtg., T42-02 San Francisco.

  14. Prediction and Validation of Heat Release Direct Injection Diesel Engine Using Multi-Zone Model

    Science.gov (United States)

    Anang Nugroho, Bagus; Sugiarto, Bambang; Prawoto; Shalahuddin, Lukman

    2014-04-01

    The objective of this study is to develop simulation model which capable to predict heat release of diesel combustion accurately in efficient computation time. A multi-zone packet model has been applied to solve the combustion phenomena inside diesel cylinder. The model formulations are presented first and then the numerical results are validated on a single cylinder direct injection diesel engine at various engine speed and timing injections. The model were found to be promising to fulfill the objective above.

  15. Mapping Inherited Fractures in the Critical Zone Using Seismic Anisotropy From Circular Surveys

    Science.gov (United States)

    Novitsky, Christopher G.; Holbrook, W. Steven; Carr, Bradley J.; Pasquet, Sylvain; Okaya, David; Flinchum, Brady A.

    2018-04-01

    Weathering and hydrological processes in Earth's shallow subsurface are influenced by inherited bedrock structures, such as bedding planes, faults, joints, and fractures. However, these structures are difficult to observe in soil-mantled landscapes. Steeply dipping structures with a dominant orientation are detectable by seismic anisotropy, with fast wave speeds along the strike of structures. We measured shallow ( 2-4 m) seismic anisotropy using "circle shots," geophones deployed in a circle around a central shot point, in a weathered granite terrain in the Laramie Range of Wyoming. The inferred remnant fracture orientations agree with brittle fracture orientations measured at tens of meters depth in boreholes, demonstrating that bedrock fractures persist through the weathering process into the shallow critical zone. Seismic anisotropy positively correlates with saprolite thickness, suggesting that inherited bedrock fractures may control saprolite thickness by providing preferential pathways for corrosive meteoric waters to access the deep critical zone.

  16. Characterization of wind velocities in the upstream induction zone of a wind turbine using scanning continuous-wave lidars

    DEFF Research Database (Denmark)

    Simley, Eric; Angelou, Nikolas; Mikkelsen, Torben Krogh

    2016-01-01

    As a wind turbine generates power, induced velocities, lower than the freestream velocity, will be present upstream of the turbine due to perturbation of the flow by the rotor. In this study, the upstream induction zone of a 225kW horizontal axis Vestas V27 wind turbine located at the Danish...... Technical University’s Risø campus is investigated using a scanning Light Detection and Ranging (lidar) system. Three short-range continuous-wave “WindScanner” lidars are positioned in the field around the V27 turbine allowing detection of all three components of the wind velocity vectors within...... the induction zone. The time-averaged mean wind speeds at different locations in the upstream induction zone are measured by scanning a horizontal plane at hub height and a vertical plane centered at the middle of the rotor extending roughly 1.5 rotor diameters (D) upstream of the rotor. Turbulence statistics...

  17. Earthquakes Threaten Many American Schools

    Science.gov (United States)

    Bailey, Nancy E.

    2010-01-01

    Millions of U.S. children attend schools that are not safe from earthquakes, even though they are in earthquake-prone zones. Several cities and states have worked to identify and repair unsafe buildings, but many others have done little or nothing to fix the problem. The reasons for ignoring the problem include political and financial ones, but…

  18. Utilization technique on variable speed device

    International Nuclear Information System (INIS)

    1989-12-01

    This reports of workshop on power technology describes using technique on variable speed device, which deals with alternating current situation and prospect of current variable speed device, technical trend and prospect of electronics, reduce expenses by variable speed device, control technique, measurement technology, high voltage variable speed device, recent trend of inverter technology, low voltage and high voltage variable speed device control device, operating variable speed device in cooling fan, FDF application and defect case of variable speed device, cooling pump application of water variable transformer, inverter application and energy effect of ventilation equipment, application of variable speed device and analysis of the result of operation and study for application of variable speed technology.

  19. An Inexpensive and Versatile Version of Kundt's Tube for Measuring the Speed of Sound in Air

    Science.gov (United States)

    Papacosta, Pangratios; Linscheid, Nathan

    2016-01-01

    Experiments that measure the speed of sound in air are common in high schools and colleges. In the Kundt's tube experiment, a horizontal air column is adjusted until a resonance mode is achieved for a specific frequency of sound. When this happens, the cork dust in the tube is disturbed at the displacement antinode regions. The location of the…

  20. A case study of effective practice in mathematics teaching and learning informed by Valsiner's zone theory

    Science.gov (United States)

    Geiger, Vince; Anderson, Judy; Hurrell, Derek

    2017-02-01

    The characteristics that typify an effective teacher of mathematics and the environments that support effective teaching practices have been a long-term focus of educational research. In this article we report on an aspect of a larger study that investigated `best practice' in mathematics teaching and learning across all Australian states and territories. A case study from one Australian state was developed from data collected via classroom observations and semi-structured interviews with school leaders and teachers and analysed using Valsiner's zone theory. A finding of the study is that `successful' practice is strongly tied to school context and the cultural practices that have been developed by school leaders and teachers to optimise student learning opportunities. We illustrate such an alignment of school culture and practice through a vignette based on a case of one `successful' school.

  1. Typing speed, spelling accuracy, and the use of word-prediction

    Directory of Open Access Journals (Sweden)

    Marina Herold

    2008-02-01

    Full Text Available Children with spelling difficulties are limited in their participation in all written school activities. We aimed to investigate the influence of word-prediction as a tool on spelling accuracy and typing speed. To this end, we selected 80 Grade 4 - 6 children with spelling difficulties in a school for special needs to participate in a research project involving a cross-over within-subject design. The research task took the form of entering 30 words through an on-screen keyboard, with and without the use of word-prediction software. The Graded Word Spelling Test served to investigate whether there was a relationship between the children's current spelling knowledge and word-prediction efficacy. The results indicated an increase in spelling accuracy with the use of word-prediction, but at the cost of time and the tendency to use word approximations, and no significant relationship between spelling knowledge and word-prediction efficacy.

  2. Electron Beam Welding of IN792 DS: Effects of Pass Speed and PWHT on Microstructure and Hardness.

    Science.gov (United States)

    Angella, Giuliano; Barbieri, Giuseppe; Donnini, Riccardo; Montanari, Roberto; Richetta, Maria; Varone, Alessandra

    2017-09-05

    Electron Beam (EB) welding has been used to realize seams on 2 mm-thick plates of directionally solidified (DS) IN792 superalloy. The first part of this work evidenced the importance of pre-heating the workpiece to avoid the formation of long cracks in the seam. The comparison of different pre-heating temperatures (PHT) and pass speeds ( v ) allowed the identification of optimal process parameters, namely PHT = 300 °C and v = 2.5 m/min. The microstructural features of the melted zone (MZ); the heat affected zone (HAZ), and base material (BM) were investigated by optical microscopy (OM), scanning electron microscopy (SEM), energy dispersion spectroscopy (EDS), electron back-scattered diffraction (EBSD), X-ray diffraction (XRD), and micro-hardness tests. In the as-welded condition; the structure of directionally oriented grains was completely lost in MZ. The γ' phase in MZ consisted of small (20-40 nm) round shaped particles and its total amount depended on both PHT and welding pass speed, whereas in HAZ, it was the same BM. Even if the amount of γ' phase in MZ was lower than that of the as-received material, the nanometric size of the particles induced an increase in hardness. EDS examinations did not show relevant composition changes in the γ' and γ phases. Post-welding heat treatments (PWHT) at 700 and 750 °C for two hours were performed on the best samples. After PWHTs, the amount of the ordered phase increased, and the effect was more pronounced at 750 °C, while the size of γ' particles in MZ remained almost the same. The hardness profiles measured across the joints showed an upward shift, but peak-valley height was a little lower, indicating more homogeneous features in the different zones.

  3. Wind Speed Perception and Risk

    Science.gov (United States)

    Agdas, Duzgun; Webster, Gregory D.; Masters, Forrest J.

    2012-01-01

    Background How accurately do people perceive extreme wind speeds and how does that perception affect the perceived risk? Prior research on human–wind interaction has focused on comfort levels in urban settings or knock-down thresholds. No systematic experimental research has attempted to assess people's ability to estimate extreme wind speeds and perceptions of their associated risks. Method We exposed 76 people to 10, 20, 30, 40, 50, and 60 mph (4.5, 8.9, 13.4, 17.9, 22.3, and 26.8 m/s) winds in randomized orders and asked them to estimate wind speed and the corresponding risk they felt. Results Multilevel modeling showed that people were accurate at lower wind speeds but overestimated wind speeds at higher levels. Wind speed perceptions mediated the direct relationship between actual wind speeds and perceptions of risk (i.e., the greater the perceived wind speed, the greater the perceived risk). The number of tropical cyclones people had experienced moderated the strength of the actual–perceived wind speed relationship; consequently, mediation was stronger for people who had experienced fewer storms. Conclusion These findings provide a clearer understanding of wind and risk perception, which can aid development of public policy solutions toward communicating the severity and risks associated with natural disasters. PMID:23226230

  4. Wind speed perception and risk.

    Directory of Open Access Journals (Sweden)

    Duzgun Agdas

    Full Text Available BACKGROUND: How accurately do people perceive extreme wind speeds and how does that perception affect the perceived risk? Prior research on human-wind interaction has focused on comfort levels in urban settings or knock-down thresholds. No systematic experimental research has attempted to assess people's ability to estimate extreme wind speeds and perceptions of their associated risks. METHOD: We exposed 76 people to 10, 20, 30, 40, 50, and 60 mph (4.5, 8.9, 13.4, 17.9, 22.3, and 26.8 m/s winds in randomized orders and asked them to estimate wind speed and the corresponding risk they felt. RESULTS: Multilevel modeling showed that people were accurate at lower wind speeds but overestimated wind speeds at higher levels. Wind speed perceptions mediated the direct relationship between actual wind speeds and perceptions of risk (i.e., the greater the perceived wind speed, the greater the perceived risk. The number of tropical cyclones people had experienced moderated the strength of the actual-perceived wind speed relationship; consequently, mediation was stronger for people who had experienced fewer storms. CONCLUSION: These findings provide a clearer understanding of wind and risk perception, which can aid development of public policy solutions toward communicating the severity and risks associated with natural disasters.

  5. Wind speed perception and risk.

    Science.gov (United States)

    Agdas, Duzgun; Webster, Gregory D; Masters, Forrest J

    2012-01-01

    How accurately do people perceive extreme wind speeds and how does that perception affect the perceived risk? Prior research on human-wind interaction has focused on comfort levels in urban settings or knock-down thresholds. No systematic experimental research has attempted to assess people's ability to estimate extreme wind speeds and perceptions of their associated risks. We exposed 76 people to 10, 20, 30, 40, 50, and 60 mph (4.5, 8.9, 13.4, 17.9, 22.3, and 26.8 m/s) winds in randomized orders and asked them to estimate wind speed and the corresponding risk they felt. Multilevel modeling showed that people were accurate at lower wind speeds but overestimated wind speeds at higher levels. Wind speed perceptions mediated the direct relationship between actual wind speeds and perceptions of risk (i.e., the greater the perceived wind speed, the greater the perceived risk). The number of tropical cyclones people had experienced moderated the strength of the actual-perceived wind speed relationship; consequently, mediation was stronger for people who had experienced fewer storms. These findings provide a clearer understanding of wind and risk perception, which can aid development of public policy solutions toward communicating the severity and risks associated with natural disasters.

  6. Simultaneous two-phase flow measurement of spray mixing process by means of high-speed two-color PIV

    International Nuclear Information System (INIS)

    Zhang, Ming; Xu, Min; Hung, David L S

    2014-01-01

    In this article, a novel high-speed two-color PIV optical diagnostic technique has been developed and applied to simultaneously measure the velocity flow-fields of a multi-hole spark-ignition direct injection (SIDI) fuel injector spray and its ambient gas in a high-pressure constant volume chamber. To allow for the phase discrimination between the fuel droplets and ambient gas, a special tracer-filter system was designed. Fluorescent seeding particles with Sauter mean diameter (SMD) of 4.8 µm were used to trace the gas inside the chamber. With a single high-speed Nd:YLF laser sheet (527 nm) as the incident light source, the Mie-scattering signal marked the phase of the fuel spray, while the fluorescent signal generated from the seeding particles tracked the phase of ambient gas. A high-speed camera, with an image-doubler (mounted in front of the camera lens) that divided the camera pixels into two parts focusing on the same field of view, was used to collect the Mie-scattering signal and LIF (laser induced fluorescence) signal simultaneously with two carefully selected optical filters. To accommodate the large dynamic range of velocities in the two phases (1–2 orders of magnitude difference), two separation times (dt) were introduced. This technique was successfully applied to the liquid spray and ambient gas two-phase flow measurement. The measurement accuracy was compared with those from LDV (laser Doppler velocimetry) measurement and good agreement was obtained. Ambient gas motion surrounding the fuel spray was investigated and characterized into three zones. The momentum transfer process between the fuel spray and ambient gas in each zone was analyzed. The two-phase flow interaction under various superheated conditions was investigated. A strengthened momentum transfer from the liquid spray to the ambient was observed with increased superheat degree. (paper)

  7. Epidemiology of intestinal helminthiasis among school children with emphasis on Schistosoma mansoni infection in Wolaita zone, Southern Ethiopia

    Directory of Open Access Journals (Sweden)

    Bereket Alemayehu

    2017-06-01

    Full Text Available Abstract Background Intestinal helminth infections are major parasitic diseases causing public health problems in Ethiopia. Although the epidemiology of these infections are well documented in Ethiopia, new transmission foci for schistosomiasis are being reported in different parts of the country. The objective of this study was to assess the prevalence of Schistosoma mansoni and other intestinal helminth infections among school children and determine the endemicity of schistosomiasis in Wolaita Zone, southern Ethiopia. Methods Cross-sectional parasitological and malacological surveys were conducted by collecting stool samples for microscopic examination and snails for intermediate host identification. Stool samples were collected from 503 children and processed for microscopic examination using Kato-Katz and formalin-ether concentration methods. Snails collected from aquatic environments in the study area were identified to species level and Biomphalaria pfeifferi snails, the intermediate host of S. mansoni,, were individually exposed to artificial light in order to induce cercariae shedding. Cercariae shed from snails were used to infect laboratory-bred Swiss albino mice in order to identify the schistosome to species level. Results The overall prevalence of intestinal helminth infections was 72.2% among school children. S. mansoni infection prevalence was 58.6%. The prevalence and intensity of S. mansoni infections varied among schools and sex of children. Swimming was the only factor reported to be significantly associated with S. mansoni infection (AOR = 2.954, 95% CI:1.962-4.449. Other intestinal helminth species identified were hookworms (27.6%, Ascaris lumbricoides (8.7%, E. vermicularis (2.8%, Taenia species (2.6%, T. trichiura (1.2% and H. nana (0.6%. Only B. pfeifferi snails collected from streams shed schistosome cercariae and 792 adult S. mansoni worms were harvested from mice exposed to cercariae shed from B. pfeifferi on the 6th

  8. Balancing Biomechanical Constraints: Optimal Escape Speeds When There Is a Trade-off between Speed and Maneuverability.

    Science.gov (United States)

    Clemente, C J; Wilson, R S

    2015-12-01

    The ability for prey to escape a pursuing predator is dependent both on the prey's speed away from the threat and on their ability to rapidly change directions, or maneuverability. Given that the biomechanical trade-off between speed and maneuverability limits the simultaneous maximization of both performance traits, animals should not select their fastest possible speeds when running away from a pursuing predator but rather a speed that maximizes the probability of successful escape. We explored how variation in the relationship between speed and maneuverability-or the shape of the trade-off-affects the optimal choice of speed for escaping predators. We used tablet-based games that simulated interactions between predators and prey (human subjects acting as predators attempting to capture "prey" moving across a screen). By defining a specific relationship between speed and maneuverability, we could test the survival of each of the possible behavioral choices available to this phenotype, i.e., the best combination of speed and maneuverability for prey fitness, based on their ability to escape. We found that the shape of the trade-off function affected the prey's optimal speed for success in escaping, the prey's maximum performance in escaping, and the breadth of speeds over which the prey's performance was high. The optimal speed for escape varied only when the trade-off between speed and maneuverability was non-linear. Phenotypes possessing trade-off functions for which maneuverability was only compromised at high speeds exhibited lower optimal speeds. Phenotypes that exhibited greater increases in maneuverability for any decrease in speed were more likely to have broader ranges of performance, meaning that individuals could attain their maximum performance across a broader range of speeds. We also found that there was a differential response of the subject's learning to these different components of locomotion. With increased experience through repeated trials

  9. Swarming, schooling, milling: phase diagram of a data-driven fish school model

    Science.gov (United States)

    Calovi, Daniel S.; Lopez, Ugo; Ngo, Sandrine; Sire, Clément; Chaté, Hugues; Theraulaz, Guy

    2014-01-01

    We determine the basic phase diagram of the fish school model derived from data by Gautrais et al (2012 PLoS Comput. Biol. 8 e1002678), exploring its parameter space beyond the parameter values determined experimentally on groups of barred flagtails (Kuhlia mugil) swimming in a shallow tank. A modified model is studied alongside the original one, in which an additional frontal preference is introduced in the stimulus/response function to account for the angular weighting of interactions. Our study, mostly limited to groups of moderate size (in the order of 100 individuals), focused not only on the transition to schooling induced by increasing the swimming speed, but also on the conditions under which a school can exhibit milling dynamics and the corresponding behavioural transitions. We show the existence of a transition region between milling and schooling, in which the school exhibits multistability and intermittence between schooling and milling for the same combination of individual parameters. We also show that milling does not occur for arbitrarily large groups, mainly due to a distance dependence interaction of the model and information propagation delays in the school, which cause conflicting reactions for large groups. We finally discuss the biological significance of our findings, especially the dependence of behavioural transitions on social interactions, which were reported by Gautrais et al to be adaptive in the experimental conditions.

  10. Swarming, schooling, milling: phase diagram of a data-driven fish school model

    International Nuclear Information System (INIS)

    Calovi, Daniel S; Lopez, Ugo; Theraulaz, Guy; Ngo, Sandrine; Chaté, Hugues; Sire, Clément

    2014-01-01

    We determine the basic phase diagram of the fish school model derived from data by Gautrais et al (2012 PLoS Comput. Biol. 8 e1002678), exploring its parameter space beyond the parameter values determined experimentally on groups of barred flagtails (Kuhlia mugil) swimming in a shallow tank. A modified model is studied alongside the original one, in which an additional frontal preference is introduced in the stimulus/response function to account for the angular weighting of interactions. Our study, mostly limited to groups of moderate size (in the order of 100 individuals), focused not only on the transition to schooling induced by increasing the swimming speed, but also on the conditions under which a school can exhibit milling dynamics and the corresponding behavioural transitions. We show the existence of a transition region between milling and schooling, in which the school exhibits multistability and intermittence between schooling and milling for the same combination of individual parameters. We also show that milling does not occur for arbitrarily large groups, mainly due to a distance dependence interaction of the model and information propagation delays in the school, which cause conflicting reactions for large groups. We finally discuss the biological significance of our findings, especially the dependence of behavioural transitions on social interactions, which were reported by Gautrais et al to be adaptive in the experimental conditions. (paper)

  11. HELIOSEISMIC INVESTIGATION OF EMERGING MAGNETIC FLUX IN THE SOLAR CONVECTION ZONE

    Energy Technology Data Exchange (ETDEWEB)

    Ilonidis, Stathis; Zhao, Junwei; Hartlep, Thomas, E-mail: ilonidis@stanford.edu [W. W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305-4085 (United States)

    2013-11-10

    Helioseismology is capable of detecting signatures of emerging sunspot regions in the solar interior before they appear at the surface. Here we present measurements that show the rising motion of the acoustic travel-time perturbation signatures in the deep convection zone, and study the possible physical origin of these signatures using observational and numerical simulation data. Our results show that the detected signatures first appear at deeper layers and then rise, with velocities of up to 1 km s{sup –1}, to shallower regions. We find evidences that these signatures may not be caused by subsurface flows or wave-speed perturbations, but are associated with acoustic power variations and frequency shifts of the cross-covariance function measured in the emerging-flux region. We also confirm with the use of numerical simulation data that phase travel-time shifts can be associated with frequency shifts related to acoustic power variations. The results of this work reveal the rising motion of magnetic flux in the deep convection zone and explain the large amplitude of the detected perturbation signatures.

  12. HELIOSEISMIC INVESTIGATION OF EMERGING MAGNETIC FLUX IN THE SOLAR CONVECTION ZONE

    International Nuclear Information System (INIS)

    Ilonidis, Stathis; Zhao, Junwei; Hartlep, Thomas

    2013-01-01

    Helioseismology is capable of detecting signatures of emerging sunspot regions in the solar interior before they appear at the surface. Here we present measurements that show the rising motion of the acoustic travel-time perturbation signatures in the deep convection zone, and study the possible physical origin of these signatures using observational and numerical simulation data. Our results show that the detected signatures first appear at deeper layers and then rise, with velocities of up to 1 km s –1 , to shallower regions. We find evidences that these signatures may not be caused by subsurface flows or wave-speed perturbations, but are associated with acoustic power variations and frequency shifts of the cross-covariance function measured in the emerging-flux region. We also confirm with the use of numerical simulation data that phase travel-time shifts can be associated with frequency shifts related to acoustic power variations. The results of this work reveal the rising motion of magnetic flux in the deep convection zone and explain the large amplitude of the detected perturbation signatures

  13. Cognitive Risk Factors for Specific Learning Disorder: Processing Speed, Temporal Processing, and Working Memory.

    Science.gov (United States)

    Moll, Kristina; Göbel, Silke M; Gooch, Debbie; Landerl, Karin; Snowling, Margaret J

    2016-01-01

    High comorbidity rates between reading disorder (RD) and mathematics disorder (MD) indicate that, although the cognitive core deficits underlying these disorders are distinct, additional domain-general risk factors might be shared between the disorders. Three domain-general cognitive abilities were investigated in children with RD and MD: processing speed, temporal processing, and working memory. Since attention problems frequently co-occur with learning disorders, the study examined whether these three factors, which are known to be associated with attention problems, account for the comorbidity between these disorders. The sample comprised 99 primary school children in four groups: children with RD, children with MD, children with both disorders (RD+MD), and typically developing children (TD controls). Measures of processing speed, temporal processing, and memory were analyzed in a series of ANCOVAs including attention ratings as covariate. All three risk factors were associated with poor attention. After controlling for attention, associations with RD and MD differed: Although deficits in verbal memory were associated with both RD and MD, reduced processing speed was related to RD, but not MD; and the association with RD was restricted to processing speed for familiar nameable symbols. In contrast, impairments in temporal processing and visuospatial memory were associated with MD, but not RD. © Hammill Institute on Disabilities 2014.

  14. Spatial Vertical Directionality and Correlation of Low-Frequency Ambient Noise in Deep Ocean Direct-Arrival Zones

    Directory of Open Access Journals (Sweden)

    Qiulong Yang

    2018-01-01

    Full Text Available Wind-driven and distant shipping noise sources contribute to the total noise field in the deep ocean direct-arrival zones. Wind-driven and distant shipping noise sources may significantly and simultaneously affect the spatial characteristics of the total noise field to some extent. In this work, a ray approach and parabolic equation solution method were jointly utilized to model the low-frequency ambient noise field in a range-dependent deep ocean environment by considering their calculation accuracy and efficiency in near-field wind-driven and far-field distant shipping noise fields. The reanalysis databases of National Center of Environment Prediction (NCEP and Volunteer Observation System (VOS were used to model the ambient noise source intensity and distribution. Spatial vertical directionality and correlation were analyzed in three scenarios that correspond to three wind speed conditions. The noise field was dominated by distant shipping noise sources when the wind speed was less than 3 m/s, and then the spatial vertical directionality and vertical correlation of the total noise field were nearly consistent with those of distant shipping noise field. The total noise field was completely dominated by near field wind generated noise sources when the wind speed was greater than 12 m/s at 150 Hz, and then the spatial vertical correlation coefficient and directionality pattern of the total noise field was approximately consistent with that of the wind-driven noise field. The spatial characteristics of the total noise field for wind speeds between 3 m/s and 12 m/s were the weighted results of wind-driven and distant shipping noise fields. Furthermore, the spatial characteristics of low-frequency ambient noise field were compared with the classical Cron/Sherman deep water noise field coherence function. Simulation results with the described modeling method showed good agreement with the experimental measurement results based on the vertical line

  15. Spatial Vertical Directionality and Correlation of Low-Frequency Ambient Noise in Deep Ocean Direct-Arrival Zones

    Science.gov (United States)

    Yang, Qiulong; Yang, Kunde; Cao, Ran; Duan, Shunli

    2018-01-01

    Wind-driven and distant shipping noise sources contribute to the total noise field in the deep ocean direct-arrival zones. Wind-driven and distant shipping noise sources may significantly and simultaneously affect the spatial characteristics of the total noise field to some extent. In this work, a ray approach and parabolic equation solution method were jointly utilized to model the low-frequency ambient noise field in a range-dependent deep ocean environment by considering their calculation accuracy and efficiency in near-field wind-driven and far-field distant shipping noise fields. The reanalysis databases of National Center of Environment Prediction (NCEP) and Volunteer Observation System (VOS) were used to model the ambient noise source intensity and distribution. Spatial vertical directionality and correlation were analyzed in three scenarios that correspond to three wind speed conditions. The noise field was dominated by distant shipping noise sources when the wind speed was less than 3 m/s, and then the spatial vertical directionality and vertical correlation of the total noise field were nearly consistent with those of distant shipping noise field. The total noise field was completely dominated by near field wind generated noise sources when the wind speed was greater than 12 m/s at 150 Hz, and then the spatial vertical correlation coefficient and directionality pattern of the total noise field was approximately consistent with that of the wind-driven noise field. The spatial characteristics of the total noise field for wind speeds between 3 m/s and 12 m/s were the weighted results of wind-driven and distant shipping noise fields. Furthermore, the spatial characteristics of low-frequency ambient noise field were compared with the classical Cron/Sherman deep water noise field coherence function. Simulation results with the described modeling method showed good agreement with the experimental measurement results based on the vertical line array deployed near

  16. Real time forecasting for an experimental oil spill in the arctic marginal ice zone

    International Nuclear Information System (INIS)

    Reed, M.; Aamo, O.M.

    1994-01-01

    The conference paper deals with the oil spill trajectory and weathering model OILMAP used to forecast spill trajectories for an experimental oil spill in the Barents Sea marginal ice zone. The model includes capabilities to enter graphically and display environmental data governing oil behavior: ice fields, tidal and background current fields, and wind time series, as well as geographical map information. Forecasts can also be updated from observations such as airplane overflights. The model performed well when wind was ''off-ice'' and speeds were relatively low (3-7 m/sec), with ice cover between 60% and 90%. Errors in forecasting the trajectory could be directly attributed to errors in the wind forecasts. Appropriate drift parameters for oil and ice were about 2.5% of the wind speed, with an Ekman veering angle of 35 o to the right. Ice sheets were typically 1 m thick. When the wind became ''on-ice'', speeds increased to about 10 m/sec, and trajectory simulations began to diverge from the observations, with observed drift parameters being 1.5% of the wind speed with a 60 o veering angle. Although, simple assumptions for the large scale movement of oil in dense ice fields appear appropriate, the importance of good wind forecasts as a basis for reliable trajectory prognoses cannot be overstated. 6 refs., 9 figs

  17. Speed management : enforcement and new technologies.

    NARCIS (Netherlands)

    Wegman, F.C.M. & Goldenbeld, C.

    2006-01-01

    Due to the massive character of speeding and inappropriate travel speeds, speed management continues to be an important and challenging policy area. Estimates are that in about a quarter to one third of fatal crashes excessive speeds are involved, making speed one of the crucial factors in road

  18. Results of Summer Enrichment Program to Promote High School Students' Interest in Engineering

    Science.gov (United States)

    Hart, Brenda; McAnulty, Kate

    2014-01-01

    For more than thirty years, personnel from the University of Louisville J.B. Speed School of Engineering have presented a summer program targeting high school students historically underrepresented in engineering fields. INSPIRE provides these students with an introduction to careers in engineering and assists the students in planning their…

  19. High-speed AC motors

    Energy Technology Data Exchange (ETDEWEB)

    Jokinen, T.; Arkkio, A. [Helsinki University of Technology Laboratory of Electromechanics, Otaniemi (Finland)

    1997-12-31

    The paper deals with various types of highspeed electric motors, and their limiting powers. Standard machines with laminated rotors can be utilised if the speed is moderate. The solid rotor construction makes it possible to reach higher power and speed levels than those of laminated rotors. The development work on high-speed motors done at Helsinki University of Technology is presented, too. (orig.) 12 refs.

  20. Comparison of physical activities of female football players in junior high school and high school.

    Science.gov (United States)

    Inoue, Yuri; Otani, Yoshitaka; Takemasa, Seiichi

    2017-08-01

    [Purpose] This study aimed to compare physical activities between junior high school and high school female football players in order to explain the factors that predispose to a higher incidence of sports injuries in high school female football players. [Subjects and Methods] Twenty-nine female football players participated. Finger floor distance, the center of pressure during single limb stance with eyes open and closed, the 40-m linear sprint time, hip abduction and extension muscle strength and isokinetic knee flexion and extension peak torque were measured. The modified Star Excursion Balance Test, the three-steps bounding test and three-steps hopping tests, agility test 1 (Step 50), agility test 2 (Forward run), curl-up test for 30 seconds and the Yo-Yo intermittent recovery test were performed. [Results] The high school group was only significantly faster than the junior high school group in the 40-m linear sprint time and in the agility tests. The distance of the bounding test in the high school group was longer than that in the junior high school group. [Conclusion] Agility and speed increase with growth; however, muscle strength and balance do not develop alongside. This unbalanced development may cause a higher incidence of sports injuries in high school football players.

  1. Everyone Deserves a Speeding Ticket.

    Science.gov (United States)

    Burris, Harold

    1993-01-01

    Presents a first day physics activity having students determine the fine for a speeding ticket if the speeds considered include the earth's rotation and revolution speed, and the movement through the galaxy. (MDH)

  2. Conjecture with water and rheological control for subducting slab in the mantle transition zone

    Directory of Open Access Journals (Sweden)

    Fumiko Tajima

    2015-01-01

    Full Text Available Seismic observations have shown structural variation near the base of the mantle transition zone (MTZ where subducted cold slabs, as visualized with high seismic speed anomalies (HSSAs, flatten to form stagnant slabs or sink further into the lower mantle. The different slab behaviors were also accompanied by variation of the “660 km” discontinuity depths and low viscosity layers (LVLs beneath the MTZ that are suggested by geoid inversion studies. We address that deep water transport by subducted slabs and dehydration from hydrous slabs could affect the physical properties of mantle minerals and govern slab dynamics. A systematic series of three-dimensional numerical simulation has been conducted to examine the effects of viscosity reduction or contrast between slab materials on slab behaviors near the base of the MTZ. We found that the viscosity reduction of subducted crustal material leads to a separation of crustal material from the slab main body and its transient stagnation in the MTZ. The once trapped crustal materials in the MTZ eventually sink into the lower mantle within 20–30 My from the start of the plate subduction. The results suggest crustal material recycle in the whole mantle that is consistent with evidence from mantle geochemistry as opposed to a two-layer mantle convection model. Because of the smaller capacity of water content in lower mantle minerals than in MTZ minerals, dehydration should occur at the phase transformation depth, ∼660 km. The variation of the discontinuity depths and highly localized low seismic speed anomaly (LSSA zones observed from seismic P waveforms in a relatively high frequency band (∼1 Hz support the hypothesis of dehydration from hydrous slabs at the phase boundary. The LSSAs which correspond to dehydration induced fluids are likely to be very local, given very small hydrogen (H+ diffusivity associated with subducted slabs. The image of such local LSSA zones embedded in HSSAs may not

  3. The influence of cooling parameters on the speed of continuous steel casting

    Science.gov (United States)

    Tirian, G. O.; Gheorghiu, C. A.; Hepuţ, T.; Chioncel, C. P.

    2018-01-01

    This paper analyzes the cooling parameters of the continuous casting speed. In the researches carried out we aimed to establish some correlation equations between the parameters characterizing the continuous casting process, the temperature of the steel at the entrance to the crystallizer, the superheating of the steel and the flow of the cooling water in the crystallizer and different zones of the secondary cooling. Parallel to these parameters were also the values for the casting speed. The research was made for the casting of round ϕ270mm semi-finished steel products. The steel was developed in an electric EBT furnace with a capacity of 100t, treated in L.F. (Ladle - Furnace) and VD (Vacuum-Degassing) and poured in a 5-wire continuous casting plant. The obtained data was processed in MATLAB using three types of correlation equations. The obtained results are presented both in the analytical and graphical form, each correlation being analyzed from the technological point of view, indicating the optimal values for the independent parameters monitored. In the analysis we present a comparison between the results obtained after the three types of equations for each correlation.

  4. Fault zone hydrogeology

    Science.gov (United States)

    Bense, V. F.; Gleeson, T.; Loveless, S. E.; Bour, O.; Scibek, J.

    2013-12-01

    Deformation along faults in the shallow crust (research effort of structural geologists and hydrogeologists. However, we find that these disciplines often use different methods with little interaction between them. In this review, we document the current multi-disciplinary understanding of fault zone hydrogeology. We discuss surface- and subsurface observations from diverse rock types from unlithified and lithified clastic sediments through to carbonate, crystalline, and volcanic rocks. For each rock type, we evaluate geological deformation mechanisms, hydrogeologic observations and conceptual models of fault zone hydrogeology. Outcrop observations indicate that fault zones commonly have a permeability structure suggesting they should act as complex conduit-barrier systems in which along-fault flow is encouraged and across-fault flow is impeded. Hydrogeological observations of fault zones reported in the literature show a broad qualitative agreement with outcrop-based conceptual models of fault zone hydrogeology. Nevertheless, the specific impact of a particular fault permeability structure on fault zone hydrogeology can only be assessed when the hydrogeological context of the fault zone is considered and not from outcrop observations alone. To gain a more integrated, comprehensive understanding of fault zone hydrogeology, we foresee numerous synergistic opportunities and challenges for the discipline of structural geology and hydrogeology to co-evolve and address remaining challenges by co-locating study areas, sharing approaches and fusing data, developing conceptual models from hydrogeologic data, numerical modeling, and training interdisciplinary scientists.

  5. Investigation of the Impact of the Upstream Induction Zone on LIDAR Measurement Accuracy for Wind Turbine Control Applications using Large-Eddy Simulation

    International Nuclear Information System (INIS)

    Simley, Eric; Pao, Lucy Y; Gebraad, Pieter; Churchfield, Matthew

    2014-01-01

    Several sources of error exist in lidar measurements for feedforward control of wind turbines including the ability to detect only radial velocities, spatial averaging, and wind evolution. This paper investigates another potential source of error: the upstream induction zone. The induction zone can directly affect lidar measurements and presents an opportunity for further decorrelation between upstream wind and the wind that interacts with the rotor. The impact of the induction zone is investigated using the combined CFD and aeroelastic code SOWFA. Lidar measurements are simulated upstream of a 5 MW turbine rotor and the true wind disturbances are found using a wind speed estimator and turbine outputs. Lidar performance in the absence of an induction zone is determined by simulating lidar measurements and the turbine response using the aeroelastic code FAST with wind inputs taken far upstream of the original turbine location in the SOWFA wind field. Results indicate that while measurement quality strongly depends on the amount of wind evolution, the induction zone has little effect. However, the optimal lidar preview distance and circular scan radius change slightly due to the presence of the induction zone

  6. Estimation of effective wind speed

    Science.gov (United States)

    Østergaard, K. Z.; Brath, P.; Stoustrup, J.

    2007-07-01

    The wind speed has a huge impact on the dynamic response of wind turbine. Because of this, many control algorithms use a measure of the wind speed to increase performance, e.g. by gain scheduling and feed forward. Unfortunately, no accurate measurement of the effective wind speed is online available from direct measurements, which means that it must be estimated in order to make such control methods applicable in practice. In this paper a new method is presented for the estimation of the effective wind speed. First, the rotor speed and aerodynamic torque are estimated by a combined state and input observer. These two variables combined with the measured pitch angle is then used to calculate the effective wind speed by an inversion of a static aerodynamic model.

  7. An Investigation of TIG welding parameters on microhardness and microstructure of heat affected zone of HSLA steel

    Science.gov (United States)

    Musa, M. H. A.; Maleque, M. A.; Ali, M. Y.

    2018-01-01

    Nowadays a wide variety of metal joining methods are used in fabrication industries. In this study, the effect of various welding parameters of the TIG welding process on microhardness, depth, and microstructure of the heat-affected zone (HAZ) of L450 HSLA steel and optimizing these process parameters following Taguchi experimental design was investigated. The microhardness tended to increase significantly with the increase of welding speed from 1.0 to 2.5 mm/s whereas the width of HAZ decreased. The current and arc voltage was found to be less significant in relative comparison. Microstructures of the welded samples were also studied to analyze the changes in the microstructure of the material in terms of ferrite, pearlite, bainite, and martensite formations. Welding speed was found to be the most significant factors leading to changes in microhardness and metallurgical properties. The increase of welding heat input caused an increase in width (depth) of HAZ and the growth of prior austenite grains and then enlarged the grain size of coarse grain heat affected zone (CGHAZ). However, the amount of martensite in the HAZ decreased accompanied by an opposite change of paint. It was observed that the hardness properties and the microstructural feature of HAZ area was strongly affected by the welding parameters.

  8. Effect of Exercise Program Speed, Agility, and Quickness (SAQ) in Improving Speed, Agility, and Acceleration

    Science.gov (United States)

    Azmi, K.; Kusnanik, N. W.

    2018-01-01

    This study aimed to analyze the effect of speed, agility and quickness training program to increase in speed, agility and acceleration. This study was conducted at 26 soccer players and divided into 2 groups with 13 players each group. Group 1 was given SAQ training program, and Group 2 conventional training program for 8 weeks. This study used a quantitative approach with quasi-experimental method. The design of this study used a matching-only design. Data was collected by testing 30-meter sprint (speed), agility t-test (agility), and run 10 meters (acceleration) during the pretest and posttest. Furthermore, the data was analyzed using paired sample t-test and independent t-test. The results showed: that there was a significant effect of speed, agility and quickness training program in improving in speed, agility and acceleration. In summary, it can be concluded that the speed, agility and quickness training program can improve the speed, agility and acceleration of the soccer players.

  9. Factors Influencing Examination Malpractice in Secondary Schools ...

    African Journals Online (AJOL)

    The main purpose of this study was to investigate factors influencing examination malpractice in some selected secondary schools in Cross River State, Nigeria. A sample of one thousand two hundred (1200) students were selected across the three educational zones of Ogoja, Ikom and Calabar using stratified, random ...

  10. A Survey of Secondary School Students' Reading Strategy Use ...

    African Journals Online (AJOL)

    A Survey of Secondary School Students' Reading Strategy Use, Teachers' ... Jimma Zone as well as their English teachers' perceived use of reading strategies ... 16 items that deal with the reading strategies they use when they teach reading ...

  11. Self-monitoring of driving speed.

    Science.gov (United States)

    Etzioni, Shelly; Erev, Ido; Ishaq, Robert; Elias, Wafa; Shiftan, Yoram

    2017-09-01

    In-vehicle data recorders (IVDR) have been found to facilitate safe driving and are highly valuable in accident analysis. Nevertheless, it is not easy to convince drivers to use them. Part of the difficulty is related to the "Big Brother" concern: installing IVDR impairs the drivers' privacy. The "Big Brother" concern can be mitigated by adding a turn-off switch to the IVDR. However, this addition comes at the expense of increasing speed variability between drivers, which is known to impair safety. The current experimental study examines the significance of this negative effect of a turn-off switch under two experimental settings representing different incentive structures: small and large fines for speeding. 199 students were asked to participate in a computerized speeding dilemma task, where they could control the speed of their "car" using "brake" and "speed" buttons, corresponding to automatic car foot pedals. The participants in two experimental conditions had IVDR installed in their "cars", and were told that they could turn it off at any time. Driving with active IVDR implied some probability of "fines" for speeding, and the two experimental groups differed with respect to the fine's magnitude, small or large. The results indicate that the option to use IVDR reduced speeding and speed variance. In addition, the results indicate that the reduction of speed variability was maximal in the small fine group. These results suggest that using IVDR with gentle fines and with a turn-off option maintains the positive effect of IVDR, addresses the "Big Brother" concern, and does not increase speed variance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Speed mathematics

    CERN Document Server

    Handley, Bill

    2012-01-01

    This new, revised edition of the bestselling Speed Mathematics features new chapters on memorising numbers and general information, calculating statistics and compound interest, square roots, logarithms and easy trig calculations. Written so anyone can understand, this book teaches simple strategies that will enable readers to make lightning-quick calculations. People who excel at mathematics use better strategies than the rest of us; they are not necessarily more intelligent. With Speed Mathematics you'll discover methods to make maths easy and fun. This book is perfect for stud

  13. Modeling pedestrian crossing speed profiles considering speed change behavior for the safety assessment of signalized intersections.

    Science.gov (United States)

    Iryo-Asano, Miho; Alhajyaseen, Wael K M

    2017-11-01

    Pedestrian safety is one of the most challenging issues in road networks. Understanding how pedestrians maneuver across an intersection is the key to applying countermeasures against traffic crashes. It is known that the behaviors of pedestrians at signalized crosswalks are significantly different from those in ordinary walking spaces, and they are highly influenced by signal indication, potential conflicts with vehicles, and intersection geometries. One of the most important characteristics of pedestrian behavior at crosswalks is the possible sudden speed change while crossing. Such sudden behavioral change may not be expected by conflicting vehicles, which may lead to hazardous situations. This study aims to quantitatively model the sudden speed changes of pedestrians as they cross signalized crosswalks under uncongested conditions. Pedestrian speed profiles are collected from empirical data and speed change events are extracted assuming that the speed profiles are stepwise functions. The occurrence of speed change events is described by a discrete choice model as a function of the necessary walking speed to complete crossing before the red interval ends, current speed, and the presence of turning vehicles in the conflict area. The amount of speed change before and after the event is modeled using regression analysis. A Monte Carlo simulation is applied for the entire speed profile of the pedestrians. The results show that the model can represent the pedestrian travel time distribution more accurately than the constant speed model. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Integrated Optimization of Speed Profiles and Power Split for a Tram with Hybrid Energy Storage Systems on a Signalized Route

    Directory of Open Access Journals (Sweden)

    Zhuang Xiao

    2018-02-01

    Full Text Available A tram with on-board hybrid energy storage systems based on batteries and supercapacitors is a new option for the urban traffic system. This configuration enables the tram to operate in both catenary zones and catenary-free zones, and the storage of regenerative braking energy for later usage. This paper presents a multiple phases integrated optimization (MPIO method for the coordination of speed profiles and power split considering the signal control strategy. The objective is to minimize the equivalent total energy consumption of all the power sources, which includes both the energy from the traction substation and energy storage systems. The constraints contain running time, variable gradients and curves, speed limits, power balance and signal time at some intersections. The integrated optimization problem is formulated as a multiple phases model based on the characters of the signalized route. An integrated calculation framework, using hp-adaptive pseudospectral method, is proposed for the integrated optimization problem. The effectiveness of the method is verified under fixed time signal (FTS control strategy and tram priority signal (TPS control strategy. Illustrative results show that this method can be successfully applied for trams with hybrid energy storage systems to improve their energy efficiency.

  15. On use of weld zone temperatures for online monitoring of weld quality in friction stir welding of naturally aged aluminium alloys

    International Nuclear Information System (INIS)

    Imam, Murshid; Biswas, Kajal; Racherla, Vikranth

    2013-01-01

    Highlights: • FSWs for 6063-T4 AA are done at different process parameters and sheet thicknesses. • Weld nugget zone and heat affected zone temperatures are monitored for each case. • Microstructural and mechanical characterisation of welds is done in all cases. • Weld ductility is found to be particularly sensitive to weld zone temperatures. • Strong correlation is found between WNZ and HAZ temperatures and weld properties. - Abstract: 6063-T4 aluminium alloy sheets of 3 and 6 mm thicknesses were friction stir butt welded using a square tool pin at a wide range of tool rotational speeds. Properties of obtained welds were characterised using tensile tests, optical micrographs, X-ray diffraction, and transmission electron microscopy. Shape, size, and distribution of precipitates in weld zones, and strength and ductility of welds were seen to directly correlate with peak temperatures in weld nugget and heat affected zones, independent of sheet thickness. In addition, fluctuations in measured temperature profiles, for 3 mm sheets, were seen to correlate with an increase in scatter of weld nugget zone properties for 3 mm sheets. Optimal weld strength and ductility were obtained for peak weld nugget zone temperatures of around 450 °C and corresponding peak heat affected zone temperatures of around 360–380 °C. Results obtained suggest that, at least for naturally aged aluminium alloys, nature of temperature evolution and magnitudes of peak temperatures in weld nugget and heat affected zones provide information on uniformity of properties in weld zones, overaging of heat affected zones, and formation of tunnel defects from improper material mixing at low weld zone temperatures

  16. Low speed phaselock speed control system. [for brushless dc motor

    Science.gov (United States)

    Fulcher, R. W.; Sudey, J. (Inventor)

    1975-01-01

    A motor speed control system for an electronically commutated brushless dc motor is provided which includes a phaselock loop with bidirectional torque control for locking the frequency output of a high density encoder, responsive to actual speed conditions, to a reference frequency signal, corresponding to the desired speed. The system includes a phase comparator, which produces an output in accordance with the difference in phase between the reference and encoder frequency signals, and an integrator-digital-to-analog converter unit, which converts the comparator output into an analog error signal voltage. Compensation circuitry, including a biasing means, is provided to convert the analog error signal voltage to a bidirectional error signal voltage which is utilized by an absolute value amplifier, rotational decoder, power amplifier-commutators, and an arrangement of commutation circuitry.

  17. Traffic speed management

    Directory of Open Access Journals (Sweden)

    Subotić Jovana Lj.

    2014-01-01

    Full Text Available Speed, and vehicles themselves, affect the level of service and road safety, quality of life, noise from traffic, the environment, health, air pollution, emission of carbon dioxide, global warming, the economy and consumption of non-renewable energy such as oil. Therefore, the speed management of the traffic of multiple significance and that should be primarily to provide effective and economical conditions of the modern and preventive protection of human life as the greatest treasure and then the material resources. The way to accomplish this is by using various (different measures such as: appropriate planning and projecting roads and streets, speed control, the legislation, enforcement, campaigns, education, advanced technologies (ITS.

  18. Particle count and black carbon measurements at schools in Las Vegas, NV and in the greater Salt Lake City, UT area.

    Science.gov (United States)

    Brown, Steven G; Vaughn, David L; Roberts, Paul T

    2017-11-01

    As part of two separate studies aimed to characterize ambient pollutant concentrations at schools in urban areas, we compare black carbon and particle count measurements at Adcock Elementary in Las Vegas, NV (April-June 2013), and Hunter High School in the West Valley City area of greater Salt Lake City, UT (February 2012). Both schools are in urban environments, but Adcock Elementary is next to the U.S. 95 freeway. Black carbon (BC) concentrations were 13% higher at Adcock compared to Hunter, while particle count concentrations were 60% higher. When wind speeds were low-less than 2 m/sec-both BC and particle count concentrations were significantly higher at Adcock, while concentrations at Hunter did not have as strong a variation with wind speed. When wind speeds were less than 2 m/sec, emissions from the adjacent freeway greatly affected concentrations at Adcock, regardless of wind direction. At both sites, BC and particle count concentrations peaked in the morning during commute hours. At Adcock, particle count also peaked during midday or early afternoon, when BC was low and conditions were conducive to new particle formation. While this midday peak occurred at Adcock on roughly 45% of the measured days, it occurred on only about 25% of the days at Hunter, since conditions for particle formation (higher solar radiation, lower wind speeds, lower relative humidity) were more conducive at Adcock. Thus, children attending these schools are likely to be exposed to pollution peaks during school drop-off in the morning, when BC and particle count concentrations peak, and often again during lunchtime recess when particle count peaks again. Particle count concentrations at two schools were shown to typically be independent of BC or other pollutants. At a school in close proximity to a major freeway, particle count concentrations were high during the midday and when wind speeds were low, regardless of wind direction, showing a large area of effect from roadway emissions

  19. Activity profile of 10-12-year-old Danish school girls participating in “FIFA 11 for Health” for Europe

    DEFF Research Database (Denmark)

    Ørntoft, Christina Øyangen; Madsen, Mads; Lind, Rune Rasmussen

    sessions were delivered during school time by trained teachers over 11-week-period, 2x45 min per week. Methods: A total of 34 girls were monitored. The activity profile was monitored using the ZXY tracking system (ChyronHego, Norway), during 4 of the 22 “FIFA 11 for Health” in Europe sessions for a total......Introduction: To evaluate activity profile of the girls in the health education programme, “FIFA 11 for Health” for Europe and to examine potential differences between girls involved in leisure-time sports club activities, i.e. football and other sports, and non-sport-club active girls. The 22...... of 34 girls of which 8 were football club active, 15 were involved in other leisure-time sports and 11 were non-sport-club active. Distance covered in various speed zones (Walking (0-4 km/h), jogging (4.1-8.0 km/h), running (8.1-12.0 km/h), high intensity running (12.1-16.0 km/h) and sprinting (>16 km...

  20. Flicker Mitigation by Speed Control of Permanent Magnet Synchronous Generator Variable-Speed Wind Turbines

    DEFF Research Database (Denmark)

    Hu, Weihao; Zhang, Yunqian; Chen, Zhe

    2013-01-01

    operation. A new method of flicker mitigation by controlling the rotational speed is proposed. It smoothes the 3p active power oscillations from wind shear and tower shadow effects of the wind turbine by varying the rotational speed of the PMSG. Simulation results show that damping the 3p active power...... oscillation by using the flicker mitigation speed controller is an effective means for flicker mitigation of variable speed wind turbines with full-scale back-to-back power converters and PMSG during continuous operation.......Grid-connected wind turbines are fluctuating power sources that may produce flicker during continuous operation. This paper presents a simulation model of a MW-level variable speed wind turbine with a full-scale back-to-back power converter and permanent magnet synchronous generator (PMSG...

  1. Grey Wolf based control for speed ripple reduction at low speed operation of PMSM drives.

    Science.gov (United States)

    Djerioui, Ali; Houari, Azeddine; Ait-Ahmed, Mourad; Benkhoris, Mohamed-Fouad; Chouder, Aissa; Machmoum, Mohamed

    2018-03-01

    Speed ripple at low speed-high torque operation of Permanent Magnet Synchronous Machine (PMSM) drives is considered as one of the major issues to be treated. The presented work proposes an efficient PMSM speed controller based on Grey Wolf (GW) algorithm to ensure a high-performance control for speed ripple reduction at low speed operation. The main idea of the proposed control algorithm is to propose a specific objective function in order to incorporate the advantage of fast optimization process of the GW optimizer. The role of GW optimizer is to find the optimal input controls that satisfy the speed tracking requirements. The synthesis methodology of the proposed control algorithm is detailed and the feasibility and performances of the proposed speed controller is confirmed by simulation and experimental results. The GW algorithm is a model-free controller and the parameters of its objective function are easy to be tuned. The GW controller is compared to PI one on real test bench. Then, the superiority of the first algorithm is highlighted. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  2. Intelligent Speed Adaptation in Company Vehicles

    DEFF Research Database (Denmark)

    Agerholm, Niels; Tradisauskas, Nerius; Waagepetersen, Rasmus

    2008-01-01

    This paper describes an intelligent speed adaptation project for company vehicles. The intelligent speed adaptation function in the project is both information and incentive, which means that the intelligent speed adaptation equipment gives a warning as well as penalty points if the driver...... is speeding. Each month the driver with that monthpsilas fewest points wins an award. The paper presents results concerning speed attitude on the first three of a planned 12 months test period. In all 26 vehicles and 51 drivers from six companies participate in the project. The key result is that speeding...

  3. Speed regulating Effects of Incentive-based Intelligent Speed Adaptation in the short and medium term

    DEFF Research Database (Denmark)

    Agerholm, Niels

    Speed regulating Effects of Incentive-based Intelligent Speed Adaptation in the short and medium term Despite massive improvements in vehicles’ safety equipment, more information and safer road network, inappropriate road safety is still causing that more than 250 people are killed and several...... thousands injured each year in Denmark. Until a few years ago the number of fatalities in most countries had decreased while the amount of traffic increased. However, this trend has been replaced by a more uncertain development towards a constant or even somewhat increasing risk. Inappropriate speeding...... is a central cause for the high number of fatalities on the roads. Despite speed limits, speed limit violating driving behaviour is still widespread in Denmark. Traditional solutions to prevent speed violation have been enforcement, information, and enhanced road design. It seems, however, hard to achieve...

  4. Circuit Regulates Speed Of dc Motor

    Science.gov (United States)

    Weaver, Charles; Padden, Robin; Brown, Floyd A., Jr.

    1990-01-01

    Driving circuit regulates speed of small dc permanent-magnet motor in tape recorder. Two nested feedback loops maintain speed within 1 percent of constant value. Inner loop provides coarse regulation, while outer loop removes most of variation in speed that remains in the presence of regulation by the inner loop. Compares speed of motor with commanded speed and adjusts current supplied to motor accordingly.

  5. An Analysis of Variable-Speed Wind Turbine Power-Control Methods with Fluctuating Wind Speed

    Directory of Open Access Journals (Sweden)

    Seung-Il Moon

    2013-07-01

    Full Text Available Variable-speed wind turbines (VSWTs typically use a maximum power-point tracking (MPPT method to optimize wind-energy acquisition. MPPT can be implemented by regulating the rotor speed or by adjusting the active power. The former, termed speed-control mode (SCM, employs a speed controller to regulate the rotor, while the latter, termed power-control mode (PCM, uses an active power controller to optimize the power. They are fundamentally equivalent; however, since they use a different controller at the outer control loop of the machine-side converter (MSC controller, the time dependence of the control system differs depending on whether SCM or PCM is used. We have compared and analyzed the power quality and the power coefficient when these two different control modes were used in fluctuating wind speeds through computer simulations. The contrast between the two methods was larger when the wind-speed fluctuations were greater. Furthermore, we found that SCM was preferable to PCM in terms of the power coefficient, but PCM was superior in terms of power quality and system stability.

  6. Flicker Mitigation by Speed Control of Permanent Magnet Synchronous Generator Variable-Speed Wind Turbines

    Directory of Open Access Journals (Sweden)

    Yanting Hu

    2013-07-01

    Full Text Available Grid-connected wind turbines are fluctuating power sources that may produce flicker during continuous operation. This paper presents a simulation model of a MW-level variable speed wind turbine with a full-scale back-to-back power converter and permanent magnet synchronous generator (PMSG developed in the simulation tool of PSCAD/EMTDC. Flicker emission of this system is investigated. The 3p (three times per revolution power oscillation due to wind shear and tower shadow effects is the significant part in the flicker emission of variable speed wind turbines with PMSG during continuous operation. A new method of flicker mitigation by controlling the rotational speed is proposed. It smoothes the 3p active power oscillations from wind shear and tower shadow effects of the wind turbine by varying the rotational speed of the PMSG. Simulation results show that damping the 3p active power oscillation by using the flicker mitigation speed controller is an effective means for flicker mitigation of variable speed wind turbines with full-scale back-to-back power converters and PMSG during continuous operation.

  7. Introducing a system of wind speed distributions for modeling properties of wind speed regimes around the world

    International Nuclear Information System (INIS)

    Jung, Christopher; Schindler, Dirk; Laible, Jessica; Buchholz, Alexander

    2017-01-01

    Highlights: • Evaluation of statistical properties of 10,016 empirical wind speed distributions. • Analysis of the shape of empirical wind speed distributions by L-moment ratios. • Introduction of a new system of wind speed distributions (Swd). • Random forests classification of the most appropriate distribution. • Comprehensive goodness of Swd fit evaluation on a global scale. - Abstract: Accurate modeling of empirical wind speed distributions is a crucial step in the estimation of average wind turbine power output. For this purpose, the Weibull distribution has often been fitted to empirical wind speed distributions. However, the Weibull distribution has been found to be insufficient to reproduce many wind speed regimes existing around the world. Results from previous studies demonstrate that numerous one-component distributions as well as mixture distributions provide a better goodness-of-fit to empirical wind speed distributions than the Weibull distribution. Moreover, there is considerable interest to apply a single system of distributions that can be utilized to reproduce the large majority of near-surface wind speed regimes existing around the world. Therefore, a system of wind speed distributions was developed that is capable of reproducing the main characteristics of existing wind speed regimes. The proposed system consists of two one-component distributions (Kappa and Wakeby) and one mixture distribution (Burr-Generalized Extreme Value). A random forests classifier was trained in order to select the most appropriate of these three distributions for each of 10,016 globally distributed empirical wind speed distributions. The shape of the empirical wind speed distributions was described by L-moment ratios. The L-moment ratios were used as predictor variables for the random forests classifier. The goodness-of-fit of the system of wind speed distributions was evaluated according to eleven goodness-of-fit metrics, which were merged into one

  8. 33 CFR 165.169 - Safety and Security Zones: New York Marine Inspection Zone and Captain of the Port Zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety and Security Zones: New... Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY... Areas First Coast Guard District § 165.169 Safety and Security Zones: New York Marine Inspection Zone...

  9. Drivers' perceptions regarding speeding and driving on urban residential streets with a 30 km/h speed limit

    Directory of Open Access Journals (Sweden)

    Do Duy Dinh

    2013-07-01

    Full Text Available Previous studies have shown very little information regarding drivers' opinions, attitudes and behaviours with respect to speeding and driving on urban residential streets with a 30 km/h speed limit. The present research aims to address this issue by conducting a questionnaire study with a sample of 367 Japanese drivers. The results showed that drivers tended to have positive beliefs about complying with the 30 km/h speed limit and understand the negative consequences of speeding; however, a majority of the drivers considered breaking the speed limit as a way to reduce their travel time. While the extent of speeding was found to be very serious, a number of drivers still supported the use of a 30 km/h speed limit on residential streets and favoured protecting the right of vulnerable street users. The logistic regression models developed in this study identified that the drivers who did not support the 30 km/h speed limit were associated with those who had committed traffic-law violations, who had negative beliefs about complying with the speed limit, who did not consider residents' opinions, who believed it is acceptable for them to drive at a high speed, and who felt it difficult to refrain from speeding. With regard to anti-speeding countermeasures, under drivers' point of view, streets should be designed to make the 30 km/h speed limit more credible, although this study also showed evidence supporting the application of public awareness programmes and social campaigns as speeding interventions. In addition, this research investigated drivers' speed choices in various specific driving circumstances, and six underlying factors affecting drivers' speed choices were determined. On the basic of the findings, the implications and suggestions for speeding interventions were also discussed.

  10. possible relationship between school performance and motor skills: a neural network approach. DOI: 10.5007/1980-0037.2011v13n5p373

    Directory of Open Access Journals (Sweden)

    Andrzej Tukiendorf

    2011-08-01

    Full Text Available The aim of this study was to answer the question whether a relationship exists between school grades reflecting humanistic, synthesis, ecological, and physical skills and motor skills (speed and power in middle school adolescents. The following tests were used for the evaluation of the particular motor skills: plate tapping test for the measurement of upper limb speed, Fleishman test for the measurement of lower limb speed, medicine ball throwing for the evaluation of upper limb power, and standing broad jump for lower limb power testing. The data were analyzed using a neural network approach. The results indicated that the school grades of middle school adolescents can be used to predict motor power. In this case, the linear correlation coefficient (r between the actual and predicted data exceeded the level of r = 0.9. In particular, a strong statistical impact of ecological, synthesis and physical skills on power performance was established. In contrast, a weaker correlation was observed with motor speed performance (r < 0.6. More attention should be paid to the possible relationship between school grades and motor skills in children and adolescents. This information is important, particularly for the selection of youngsters with advanced motor skills at an early age.

  11. 33 CFR 165.814 - Security Zones; Captain of the Port Houston-Galveston Zone.

    Science.gov (United States)

    2010-07-01

    ... Port Houston-Galveston Zone. 165.814 Section 165.814 Navigation and Navigable Waters COAST GUARD... § 165.814 Security Zones; Captain of the Port Houston-Galveston Zone. (a) Location. The following areas are designated as security zones: (1) Houston, Texas. The Houston Ship Channel and all associated...

  12. Effective speed management through automatic enforcement.

    NARCIS (Netherlands)

    Oei, H.-l.

    1994-01-01

    This paper analyses several aspects of the Dutch experience of speed enforcement, and presents the results of some speed management experiments in The Netherlands, using automatic warning of speeders and enforcement of speeding. Traditional approaches to manage speed there have not resulted in

  13. [Combustion zone investigation and modelling in fuel flexible suspension fired boilers]. Result summary and status

    Energy Technology Data Exchange (ETDEWEB)

    Lovmand Hvid, S.

    2011-12-15

    The project has been designed to obtain data from a power plant boiler with co-combustion, partly to gain greater knowledge of particle turnover in the fuel zone, partly to support the development of modeling tools. Data collection occurred at Studstrup Power Station Unit 4, where the fuel is a combination of coal and biomass. The boiler is equipped with 24 dust burners, four of which have been converted to firing with biomass. Measurements have been carried out in the flame zone with different fuels: coal alone, coal + straw and coal + wood. During the experiments velocity fields, temperature fields and gas concentration fields were measured in the firing zone. Also, particle samples from the flame zone ware collected. Several measurements are performed with well-known techniques, but in addition, the project developed new optical measurement methods based on UV spectroscopy. They allow measuring other gases than the hitherto known methods and allow you to gain insight into the dynamic variations beyond just mean fields. The collection of particle samples from the boiler was, as expected, a very challenging task under the given conditions, but was carried out with a largely satisfactory result. Analysis of the samples has initially failed to lead to an increased recognition of the speed of the conversion process, but the samples will be analyzed in more detail in other projects. (LN)

  14. Speed control variable rate irrigation

    Science.gov (United States)

    Speed control variable rate irrigation (VRI) is used to address within field variability by controlling a moving sprinkler’s travel speed to vary the application depth. Changes in speed are commonly practiced over areas that slope, pond or where soil texture is predominantly different. Dynamic presc...

  15. PERSONALITY AND SPEEDING

    Directory of Open Access Journals (Sweden)

    Richard TAY

    2003-01-01

    Full Text Available While there has been extensive research on the effect of sensation seeking on risky driving, relatively little research has been conducted on Type-A personality. The motivations for speeding are likely to be different for each group and these differences have important implications for the design, implementation and expected efficacy of road safety countermeasures. This paper examines the influence of sensation seeking and Type-A behavior pattern on speeding behaviour. A sample of 139 staff and students in an Australian university were surveyed in July 2001 to gather information on their gender, age, personality and self-reported speeding behaviour. The data were analysed using correlations and analysis of variance procedures. Finally, some implications for road safety are discussed.

  16. Small portable speed calculator

    Science.gov (United States)

    Burch, J. L.; Billions, J. C.

    1973-01-01

    Calculator is adapted stopwatch calibrated for fast accurate measurement of speeds. Single assembled unit is rugged, self-contained, and relatively inexpensive to manufacture. Potential market includes automobile-speed enforcement, railroads, and field-test facilities.

  17. Low Speed Control for Automatic Welding

    Science.gov (United States)

    Iceland, W. E.

    1982-01-01

    Amplifier module allows rotating positioner of automatic welding machine to operate at speeds below normal range. Low speeds are precisely regulated by a servomechanism as are normal-range speeds. Addition of module to standard welding machine makes it unnecessary to purchase new equipment for low-speed welding.

  18. Influence of the Overlapping Factor and Welding Speed on T-Joint Welding of Ti6Al4V and Inconel 600 Using Low-Power Fiber Laser

    Directory of Open Access Journals (Sweden)

    Shamini Janasekaran

    2016-06-01

    Full Text Available Double-sided laser beam welding of skin-stringer joints is an established method for many applications. However, in certain cases with limited accessibility, single-sided laser beam joining is considered. In the present study, single-sided welding of titanium alloy Ti6Al4V and nickel-based alloy Inconel 600 in a T-joint configuration was carried out using continuous-wave (CW, low-power Ytterbium (Yb-fiber laser. The influence of the overlapping factor and welding speed of the laser beam on weld morphology and properties was investigated using scanning electron microscopy (SEM and X-ray diffraction (XRD, respectively. XRD analysis revealed the presence of intermetallic layers containing NiTi and NiTi2 at the skin-stringer joint. The strength of the joints was evaluated using pull testing, while the hardness of the joints was analyzed using Vickers hardness measurement at the base metal (BM, fusion zone (FZ and heat-affected zone (HAZ. The results showed that the highest force needed to break the samples apart was approximately 150 N at a laser welding power of 250 W, welding speed of 40 mm/s and overlapping factor of 50%. During low-power single-sided laser welding, the properties of the T-joints were affected by the overlapping factor and laser welding speed.

  19. Empowerment Zone: Texas School Beats the Odds with a Shared Commitment to Student Learning

    Science.gov (United States)

    Berkey, Timothy; Dow, Elizabeth

    2008-01-01

    The odds were stacked against the new elementary school from the beginning. In its favor, the school was a beautiful building with an established principal. Beyond that, anyone would predict that the first year would be tough. The staff consisted of new teachers and transfers from across the district. The students were reassigned from two…

  20. Unconscious Local Motion Alters Global Image Speed

    Science.gov (United States)

    Khuu, Sieu K.; Chung, Charles Y. L.; Lord, Stephanie; Pearson, Joel

    2014-01-01

    Accurate motion perception of self and object speed is crucial for successful interaction in the world. The context in which we make such speed judgments has a profound effect on their accuracy. Misperceptions of motion speed caused by the context can have drastic consequences in real world situations, but they also reveal much about the underlying mechanisms of motion perception. Here we show that motion signals suppressed from awareness can warp simultaneous conscious speed perception. In Experiment 1, we measured global speed discrimination thresholds using an annulus of 8 local Gabor elements. We show that physically removing local elements from the array attenuated global speed discrimination. However, removing awareness of the local elements only had a small effect on speed discrimination. That is, unconscious local motion elements contributed to global conscious speed perception. In Experiment 2 we measured the global speed of the moving Gabor patterns, when half the elements moved at different speeds. We show that global speed averaging occurred regardless of whether local elements were removed from awareness, such that the speed of invisible elements continued to be averaged together with the visible elements to determine the global speed. These data suggest that contextual motion signals outside of awareness can both boost and affect our experience of motion speed, and suggest that such pooling of motion signals occurs before the conscious extraction of the surround motion speed. PMID:25503603

  1. Transforming Nigerian Youth Leadership Capacities in Secondary Schools through Principals' Managerial Role Effectiveness

    Science.gov (United States)

    Edet, Aniefiok Oswald; Ekpoh, Uduak Imo; Uko, Esther Samuel

    2015-01-01

    The study examined principals' management role effectiveness of secondary schools for youth leadership in Calabar Education Zone of Cross River State. The study employed survey research design. The target population comprised all 158 principals in both public and private secondary schools in the study area. The sample selected through random…

  2. Speed management program plan.

    Science.gov (United States)

    2014-05-01

    Changing public attitudes regarding speeding and speed management will require a comprehensive and concerted effort, involving a wide variety of strategies. This plan identifies six primary focus areas: : A. Data and Data-Driven Approaches, : B. Rese...

  3. Implementing the Zone of Proximal Development: From the Pedagogical Experiment to the Developmental Education System of Leonid Zankov

    Directory of Open Access Journals (Sweden)

    Liudmila G. GUSEVA

    2017-06-01

    Full Text Available This article overviews the theoretical and applied works of the psychologist and pedagogue Leonid Zankov. Zankov’s model of teaching is based on Vygotsky’s theory that appropriate teaching methods stimulate cognitive development, whose core notion is the Zone of Proximal Development. This educational psychology research was verified by large scale pedagogical experiments conducted in 1970s at public schools in Russia. Over several decades L.V. Zankov with co-workers and followers created the comprehensive system of developmental education for elementary school. The Zankov education system is used now at public schools in Russia. Its main principles and properties are described.

  4. Implementing the zone of proximal development: From the pedagogical experiment to the developmental education system of Leonid Zankov

    Directory of Open Access Journals (Sweden)

    Liudmila G. Guseva

    2017-06-01

    Full Text Available This article overviews the theoretical and applied works of the psychologist and pedagogue Leonid Zankov. Zankov’s model of teaching is based on Vygotsky’s theory that appropriate teaching methods stimulate cognitive development, whose core notion is the Zone of Proximal Development. This educational psychology research was verified by large scale pedagogical experiments conducted in 1970s at public schools in Russia. Over several decades L.V. Zankov with co-workers and followers created the comprehensive system of developmental education for elementary school. The Zankov education system is used now at public schools in Russia. Its main principles and properties are described.

  5. A study on heat-flow analysis of friction stir welding on a rotation affected zone

    International Nuclear Information System (INIS)

    Kang, Sung Wook; Jang, Beom Seon; Kim, Jae Woong

    2014-01-01

    In recent years, as interest in environmental protection and energy conservation rose, technological development for lightweight efficiency of transport equipment, such as aircrafts, railcars, automobiles and vessels, have been briskly proceeding. This has led to an expansion of the application of lightweight alloys such as aluminum and magnesium. For the welding of these lightweight alloys, friction stir welding has been in development by many researchers. Heat-flow analysis of friction stir welding is one such research. The flow and energy equation is solved using the computational fluid dynamic commercial program 'Fluent'. In this study, a rotation affected zone concept is imposed. The rotation affected zone is a constant volume. In this volume, flow is rotated the same as the tool rotation speed and so plastic dissipation occurs. Through this simulation, the temperature distribution results are calculated and the simulation results are compared with the experimental results.

  6. The Sorong Fault Zone, Indonesia: Mapping a Fault Zone Offshore

    Science.gov (United States)

    Melia, S.; Hall, R.

    2017-12-01

    The Sorong Fault Zone is a left-lateral strike-slip fault zone in eastern Indonesia, extending westwards from the Bird's Head peninsula of West Papua towards Sulawesi. It is the result of interactions between the Pacific, Caroline, Philippine Sea, and Australian Plates and much of it is offshore. Previous research on the fault zone has been limited by the low resolution of available data offshore, leading to debates over the extent, location, and timing of movements, and the tectonic evolution of eastern Indonesia. Different studies have shown it north of the Sula Islands, truncated south of Halmahera, continuing to Sulawesi, or splaying into a horsetail fan of smaller faults. Recently acquired high resolution multibeam bathymetry of the seafloor (with a resolution of 15-25 meters), and 2D seismic lines, provide the opportunity to trace the fault offshore. The position of different strands can be identified. On land, SRTM topography shows that in the northern Bird's Head the fault zone is characterised by closely spaced E-W trending faults. NW of the Bird's Head offshore there is a fold and thrust belt which terminates some strands. To the west of the Bird's Head offshore the fault zone diverges into multiple strands trending ENE-WSW. Regions of Riedel shearing are evident west of the Bird's Head, indicating sinistral strike-slip motion. Further west, the ENE-WSW trending faults turn to an E-W trend and there are at least three fault zones situated immediately south of Halmahera, north of the Sula Islands, and between the islands of Sanana and Mangole where the fault system terminates in horsetail strands. South of the Sula islands some former normal faults at the continent-ocean boundary with the North Banda Sea are being reactivated as strike-slip faults. The fault zone does not currently reach Sulawesi. The new fault map differs from previous interpretations concerning the location, age and significance of different parts of the Sorong Fault Zone. Kinematic

  7. Sound speed in the Mediterranean Sea: an analysis from a climatological data set

    Directory of Open Access Journals (Sweden)

    S. Salon

    2003-03-01

    Full Text Available This paper presents an analysis of sound speed distribution in the Mediterranean Sea based on climatological temperature and salinity data. In the upper layers, propagation is characterised by upward refraction in winter and an acoustic channel in summer. The seasonal cycle of the Mediterranean and the presence of gyres and fronts create a wide range of spatial and temporal variabilities, with relevant differences between the western and eastern basins. It is shown that the analysis of a climatological data set can help in defining regions suitable for successful monitoring by means of acoustic tomography. Empirical Orthogonal Functions (EOF decomposition on the profiles, performed on the seasonal cycle for some selected areas, demonstrates that two modes account for more than 98% of the variability of the climatological distribution. Reduced order EOF analysis is able to correctly represent sound speed profiles within each zone, thus providing the a priori knowledge for Matched Field Tomography. It is also demonstrated that salinity can affect the tomographic inversion, creating a higher degree of complexity than in the open oceans.Key words. Oceanography: general (marginal and semi-enclosed seas; ocean acoustics

  8. A two-dimensional time domain near zone to far zone transformation

    Science.gov (United States)

    Luebbers, Raymond J.; Ryan, Deirdre; Beggs, John H.; Kunz, Karl S.

    1991-01-01

    In a previous paper, a time domain transformation useful for extrapolating 3-D near zone finite difference time domain (FDTD) results to the far zone was presented. In this paper, the corresponding 2-D transform is outlined. While the 3-D transformation produced a physically observable far zone time domain field, this is not convenient to do directly in 2-D, since a convolution would be required. However, a representative 2-D far zone time domain result can be obtained directly. This result can then be transformed to the frequency domain using a Fast Fourier Transform, corrected with a simple multiplicative factor, and used, for example, to calculate the complex wideband scattering width of a target. If an actual time domain far zone result is required it can be obtained by inverse Fourier transform of the final frequency domain result.

  9. The large scale and long term evolution of the solar wind speed distribution and high speed streams

    International Nuclear Information System (INIS)

    Intriligator, D.S.

    1977-01-01

    The spatial and temporal evolution of the solar wind speed distribution and of high speed streams in the solar wind are examined. Comparisons of the solar wind streaming speeds measured at Earth, Pioneer 11, and Pioneer 10 indicate that between 1 AU and 6.4 AU the solar wind speed distributions are narrower (i.e. the 95% value minus the 5% value of the solar wind streaming speed is less) at extended heliocentric distances. These observations are consistent with one exchange of momentum in the solar wind between high speed streams and low speed streams as they propagate outward from the Sun. Analyses of solar wind observations at 1 AU from mid 1964 through 1973 confirm the earlier results reported by Intriligator (1974) that there are statistically significant variations in the solar wind in 1968 and 1969, years of solar maximum. High speed stream parameters show that the number of high speed streams in the solar wind in 1968 and 1969 is considerably more than the predicted yearly average, and in 1965 and 1972 less. Histograms of solar wind speed from 1964 through 1973 indicate that in 1968 there was the highest percentage of elevated solar wind speeds and in 1965 and 1972 the lowest. Studies by others also confirm these results although the respective authors did not indicate this fact. The duration of the streams and the histograms for 1973 imply a shifting in the primary stream source. (Auth.)

  10. Root zone effects on tracer migration in arid zones

    International Nuclear Information System (INIS)

    Tyler, S.W.; Walker, G.R.

    1994-01-01

    The study of groundwater recharge and soil water movement in arid regions has received increased attention in the search for safe disposal sites for hazardous wastes. In passing through the upper 1 to 2 m of most soil profiles, tracers indicative of recharge such as Cl, 2 H, 18 O, Br, 3 H, and 56 Cl are subjected to a wide range of processes not encountered deeper in the profile. This transition zone, where water enters as precipitation and leaves as recharge, is often ignored when environmental tracers are used to estimate deep soil water flux and recharge, yet its effect may be profound. In this work, we reexamine the processes of root extraction and its effect on the velocity and distribution of tracers. Examples are presented for idealized conditions, which show clearly the relation between the root zone processes and the deep drainage or recharge. The results indicate that, when recharge is small and root zone processes are not accounted for, tracer techniques can significantly overestimate recharge until the tracer has moved well below the root zone. By incorporating simple models of root zone processes, a clearer understanding of tracer distributions and a more accurate estimate of recharge can then be made. 11 refs., 9 figs

  11. 75 FR 50700 - Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, and Drawbridge...

    Science.gov (United States)

    2010-08-17

    ...] Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, and Drawbridge Operation... notice lists temporary safety zones, security zones, special local regulations, and drawbridge operation... responsive to the safety and security needs within their jurisdiction; therefore, District Commanders and...

  12. Radiant zone heated particulate filter

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI

    2011-12-27

    A system includes a particulate matter (PM) filter including an upstream end for receiving exhaust gas and a downstream end. A radiant zoned heater includes N zones, where N is an integer greater than one, wherein each of the N zones includes M sub-zones, where M is an integer greater than or equal to one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones, restricts exhaust gas flow in a portion of the PM filter that corresponds to the selected one of the N zones, and deactivates non-selected ones of the N zones.

  13. Sensorless Speed Control including zero speed of Non Salient PM Synchronous Drives

    DEFF Research Database (Denmark)

    Rasmussen, Henrik

    This paper presents a position sensorless drive of non salient pole PM synchronous motors for all speeds including zero speed. Using adaptive Lyapunov design a new approach for the design of an observer is developed. The resulting scheme leads to a nonlinear full order observer for the motor states...

  14. Sensorless Speed Control including zero speed of Non Salient PM Synchronous Drives

    DEFF Research Database (Denmark)

    Rasmussen, Henrik

    2005-01-01

    This paper presents a position sensorless drive of non salient pole PM synchronous motors for all speeds including zero speed. Using adaptive Lyapunov design a new approach for the design of an observer is developed. The resulting scheme leads to a nonlinear full order observer for the motor states...

  15. Sensorless speed Control including Zero Speed on Non Salient PM Synchronous Drives

    DEFF Research Database (Denmark)

    Rasmussen, Henrik

    2006-01-01

    This paper presents a position sensorless drive of non salient pole PM synchronous motors for all speeds including zero speed. Using adaptive Lyapunov design a new approach for the design of an observer is developed. The resulting scheme leads to a nonlinear full order observer for the motor states...

  16. Mechanical Properties and Wear Behavior of AA5182/WC Nanocomposite Fabricated by Friction Stir Welding at Different Tool Traverse Speeds

    Science.gov (United States)

    Paidar, Moslem; Asgari, Ali; Ojo, Olatunji Oladimeji; Saberi, Abbas

    2018-03-01

    Grain growth inhibition at the heat-affected zone, improved weld strength and superior tribological properties of welds are desirable attributes of modern manufacturing. With the focused on these attributes, tungsten carbide (WC) nanoparticles were employed as reinforcements for the friction stir welding of 5-mm-thick AA5182 aluminum alloy by varying tool traverse speeds. The microstructure, microhardness, ultimate tensile strength, fracture and wear behavior of the resultant WC-reinforced welds were investigated, while unreinforced AA5182 welds were employed as controls for the study. The result shows that the addition of WC nanoparticles causes substantial grain refinement within the weld nugget. A decrease in traverse speed caused additional particle fragmentation, improved hardness value and enhanced weld strength in the reinforced welds. Improved wear rate and friction coefficient of welds were attained at a reduced traverse speed of 100 mm/min in the WC-reinforced welds. This improvement is attributed to the effects of reduced grain size/grain fragmentation and homogeneous dispersion of WC nanoparticles within the WC-reinforced weld nugget.

  17. 393 Competencies Required by Primary School Supervisors: Basis ...

    African Journals Online (AJOL)

    Nekky Umera

    in Onitsha Education Zone, specifically, in all the Public Primary Schools in the three Local ... the competencies instruction supervisors require for effective supervision. Mean .... that…. have little to do with actual classroom observation nor improvement ..... Table 2: t-test comparison of the mean ratings of head teachers and.

  18. Game method application efficiency for speed and power capability development of trampoline athletes at the initial training stage

    Directory of Open Access Journals (Sweden)

    Alfia Deineko

    2017-06-01

    Full Text Available Purpose: to prove the effectiveness of using the game method for speed and power capability development of trampoline athletes at the initial training stage. Material & Methods: in the article the materials of the research that was carried out with the help of pedagogical testing of trampoliners of 7–8 years on the basis of the Children and Youth Sports School No. 7, Trampoline Department of Kharkov. Results: conducted pedagogical experiment showed the effectiveness of the developed methodology for the development of speed-strength abilities of trampoline athletes at the initial training stage using the game method. Conclusion: results of the experiment confirm the importance of the use of the game method for the development of speed-strength abilities in the initial training of young trampolines, which further affects the level of their technical preparedness and the effectiveness of competition activities.

  19. Information and communication technology: students' health education in 1st- to 6th-grade South Korea elementary schools.

    Science.gov (United States)

    Lee, Eunjoo; Park, Hyejin; Whyte, James; Jeong, Eunhoe

    2013-09-01

    The purposes of this study were to (1) identify school nurses' awareness of information and communication technology (ICT) use in students' health education and (2) explore the barriers or reasons for the adoption of ICT in school nursing practice, while (3) presenting strategies to speed ICT diffusion and dissemination into practice. For data collection, 209 primary school nurses in K province of Korea were selected and e-mailed the questionnaires. Collected data were analyzed as frequency, percentages, and chi-square tests. The major reasons to adopt ICT were increasing school nurses' confidence in providing health education and improving teaching methods using diverse multimedia. The major barriers to utilization of ICT were lack of time for preparation of educational materials, lack of software availability, and lack of computer skills of school nurses and students. Several strategies were suggested to speed the diffusion of ICT into students' health education, such as integrating a health education course into regular curriculum. It is important to identify barriers and reasons for adoption of ICT in school nursing. In addition, strategies should be emphasized that result in more rapid diffusion of these technologies in school nursing practice. © 2013, American School Health Association.

  20. Investigating the adaptive model of thermal comfort for naturally ventilated school buildings in Taiwan

    Science.gov (United States)

    Hwang, Ruey-Lung; Lin, Tzu-Ping; Chen, Chen-Peng; Kuo, Nai-Jung

    2009-03-01

    Divergence in the acceptability to people in different regions of naturally ventilated thermal environments raises a concern over the extent to which the ASHRAE Standard 55 may be applied as a universal criterion of thermal comfort. In this study, the ASHRAE 55 adaptive model of thermal comfort was investigated for its applicability to a hot and humid climate through a long-term field survey performed in central Taiwan among local students attending 14 elementary and high schools during September to January. Adaptive behaviors, thermal neutrality, and thermal comfort zones are explored. A probit analysis of thermal acceptability responses from students was performed in place of the conventional linear regression of thermal sensation votes against operative temperature to investigate the limits of comfort zones for 90% and 80% acceptability; the corresponding comfort zones were found to occur at 20.1-28.4°C and 17.6-30.0°C, respectively. In comparison with the yearly comfort zones recommended by the adaptive model for naturally ventilated spaces in the ASHRAE Standard 55, those observed in this study differ in the lower limit for 80% acceptability, with the observed level being 1.7°C lower than the ASHRAE-recommended value. These findings can be generalized to the population of school children, thus providing information that can supplement ASHRAE Standard 55 in evaluating the thermal performance of naturally ventilated school buildings, particularly in hot-humid areas such as Taiwan.

  1. Towards stacked zone plates

    International Nuclear Information System (INIS)

    Werner, S; Rehbein, S; Guttman, P; Heim, S; Schneider, G

    2009-01-01

    Fresnel zone plates are the key optical elements for soft and hard x-ray microscopy. For short exposure times and minimum radiation load of the specimen the diffraction efficiency of the zone plate objectives has to be maximized. As the efficiency strongly depends on the height of the diffracting zone structures the achievable aspect ratio of the nanostructures determines these limits. To reach aspect ratios ≥ 20:1 for high efficient optics we propose to superimpose zone plates on top of each other. With this multiplication approach the final aspect ratio is only limited by the number of stacked zone plate layers. For the stack process several nanostructuring process steps have to be developed and/or improved. Our results show for the first time two layers of zone plates stacked on top of each other.

  2. 76 FR 70342 - Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation...

    Science.gov (United States)

    2011-11-14

    ...] Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation... published in the Federal Register. This notice lists temporary safety zones, security zones, special local... Commanders and Captains of the Port (COTP) must be immediately responsive to the safety and security needs...

  3. 76 FR 48751 - Security Zones; Captain of the Port Lake Michigan Zone

    Science.gov (United States)

    2011-08-09

    ... Jardine Water Filtration Plant security zone would encompass all U.S. navigable waters of Lake Michigan... areas near shore to Chicago's water filtration plants; the security zones have been designed to allow.... 165.910 Security Zones; Captain of the Port Lake Michigan. (a) * * * (1) Jardine Water Filtration...

  4. Finite Element Method Analysis of An Out Flow With Free Surface In Transition Zones

    Science.gov (United States)

    Saoula, R. Iddir S.; Mokhtar, K. Ait

    The object of this work is to present this part of the fluid mechanics that relates to out-flows of the fluid to big speeds in transitions. Results usually gotten by the classic processes can only have a qualitative aspect. The method fluently used for the count of these out-flows to big speeds is the one of characteristics, this approach remains interesting so much that doesn't appear within the out-flow of intersections of shock waves, as well as of reflections of these. In the simple geometry case, the method of finite differences satisfying result, But when the complexity of this geometry imposes itself, it is the method of finite elements that is proposed to solve this type of prob- lem, in particular for problems Trans critic. The goal of our work is to analyse free surface flows in channels no prismatic has oblong transverse section in zone of tran- sition. (Convergent, divergent). The basic mathematical model of this study is Saint Venant derivatives partial equations. To solve these equations we use the finite ele- ment method, the element of reference is the triangular element with 6 nodes which are quadratic in speed and linear in height (pressure). Our results and their obtains by others are very close to experimental results.

  5. The Relationship between a Linear Combination of Intelligence, Musical Background, Rhythm Ability and Tapping Ability to Typewriting Speed and Accuracy.

    Science.gov (United States)

    Fante, Cheryl H.

    This study was conducted in an attempt to identify any predictor or combination of predictors of a beginning typewriting student's success. Variables of intelligence, rhythmic ability, musical background, and tapping ability were combined to study their relationship to typewriting speed and accuracy. A sample of 109 high school students was…

  6. High-speed, low-damage grinding of advanced ceramics Phase 1. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kovach, J.A. [Eaton Corp., Willoughby Hills, OH (United States). Mfg. Technologies Center; Malkin, S. [Univ. of Massachusetts (United States)

    1995-03-01

    In manufacture of structural ceramic components, grinding costs can comprise up to 80% of the entire manufacturing cost. Most of these costs arise from the conventional multi-step grinding process with numerous grinding wheels and additional capital equipment, perishable dressing tools, and labor. In an attempt to reduce structural ceramic grinding costs, a feasibility investigation was undertaken to develop a single step, roughing-finishing process suitable for producing high-quality silicon nitride ceramic parts at high material removal rates at lower cost than traditional, multi-stage grinding. This feasibility study employed combined use of laboratory grinding tests, mathematical grinding models, and characterization of resultant material surface condition. More specifically, this Phase 1 final report provides a technical overview of High-Speed, Low-Damage (HSLD) ceramic grinding and the conditions necessary to achieve the small grain depths of cut necessary for low damage grinding while operating at relatively high material removal rates. Particular issues addressed include determining effects of wheel speed and material removal rate on resulting mode of material removal (ductile or brittle fracture), limiting grinding forces, calculation of approximate grinding zone temperatures developed during HSLD grinding, and developing the experimental systems necessary for determining HSLD grinding energy partition relationships. In addition, practical considerations for production utilization of the HSLD process are also discussed.

  7. Speed Variance and Its Influence on Accidents.

    Science.gov (United States)

    Garber, Nicholas J.; Gadirau, Ravi

    A study was conducted to investigate the traffic engineering factors that influence speed variance and to determine to what extent speed variance affects accident rates. Detailed analyses were carried out to relate speed variance with posted speed limit, design speeds, and other traffic variables. The major factor identified was the difference…

  8. Working Memory in Children With Neurocognitive Effects From Sickle Cell Disease: Contributions of the Central Executive and Processing Speed

    Science.gov (United States)

    Smith, Kelsey E.; Schatz, Jeffrey

    2017-01-01

    Children with sickle cell disease (SCD) are at risk for working memory deficits due to multiple disease processes. We assessed working memory abilities and related functions in 32 school-age children with SCD and 85 matched comparison children using Baddeley’s working memory model as a framework. Children with SCD performed worse than controls for working memory, central executive function, and processing/rehearsal speed. Central executive function was found to mediate the relationship between SCD status and working memory, but processing speed did not. Cognitive remediation strategies that focus on central executive processes may be important for remediating working memory deficits in SCD. PMID:27759435

  9. Slow progress in changing the school food environment: nationally representative results from public and private elementary schools.

    Science.gov (United States)

    Turner, Lindsey; Chaloupka, Frank J

    2012-09-01

    Children spend much of their day in school, and authorities have called for improvements in the school food environment. However, it is not known whether changes have occurred since the federal wellness policy mandate took effect in 2006-2007. We examined whether the school food environment in public and private elementary schools changed over time and examined variations by school type and geographic division. Survey data were gathered from respondents at nationally representative samples of elementary schools during the 2006-2007 and 2009-2010 school years (respectively, 578 and 680 public schools, and 259 and 313 private schools). Topics assessed included competitive foods, school meals, and other food-related practices (eg, school gardens and nutrition education). A 16-item food environment summary score was computed, with possible scores ranging from 0 (least healthy) to 100 (healthiest). Multivariate regression models were used to examine changes over time in the total school food environment score and component items, and variations by US census division. Many practices improved, such as participation in school gardens or farm-to-school programs, and availability of whole grains and only lower-fat milks in lunches. Although the school food environment score increased significantly, the magnitude of change was small; as of 2009-2010 the average score was 53.5 for public schools (vs 50.1 in 2006-2007) and 42.2 for private schools (vs 37.2 in 2006-2007). Scores were higher in public schools than in private schools (Pschool size. For public schools, scores were higher in the Pacific and West South Central divisions compared with the national average. Changes in the school food environment have been minimal, with much room remaining for improvement. Additional policy changes may be needed to speed the pace of improvement. Copyright © 2012 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

  10. HDR 192Ir source speed measurements using a high speed video camera

    International Nuclear Information System (INIS)

    Fonseca, Gabriel P.; Viana, Rodrigo S. S.; Yoriyaz, Hélio; Podesta, Mark; Rubo, Rodrigo A.; Sales, Camila P. de; Reniers, Brigitte; Verhaegen, Frank

    2015-01-01

    Purpose: The dose delivered with a HDR 192 Ir afterloader can be separated into a dwell component, and a transit component resulting from the source movement. The transit component is directly dependent on the source speed profile and it is the goal of this study to measure accurate source speed profiles. Methods: A high speed video camera was used to record the movement of a 192 Ir source (Nucletron, an Elekta company, Stockholm, Sweden) for interdwell distances of 0.25–5 cm with dwell times of 0.1, 1, and 2 s. Transit dose distributions were calculated using a Monte Carlo code simulating the source movement. Results: The source stops at each dwell position oscillating around the desired position for a duration up to (0.026 ± 0.005) s. The source speed profile shows variations between 0 and 81 cm/s with average speed of ∼33 cm/s for most of the interdwell distances. The source stops for up to (0.005 ± 0.001) s at nonprogrammed positions in between two programmed dwell positions. The dwell time correction applied by the manufacturer compensates the transit dose between the dwell positions leading to a maximum overdose of 41 mGy for the considered cases and assuming an air-kerma strength of 48 000 U. The transit dose component is not uniformly distributed leading to over and underdoses, which is within 1.4% for commonly prescribed doses (3–10 Gy). Conclusions: The source maintains its speed even for the short interdwell distances. Dose variations due to the transit dose component are much lower than the prescribed treatment doses for brachytherapy, although transit dose component should be evaluated individually for clinical cases

  11. The Gravity Model for High School Students

    Science.gov (United States)

    Tribble, Paul; Mitchell, William A.

    1977-01-01

    The authors suggest ways in which the gravity model can be used in high school geography classes. Based on Newton's Law of Molecular Gravitation, the law states that gravitation is in direct ratio to mass and inverse ratio to distance. One activity for students involves determination of zones of influence of cities of various sizes. (Author/AV)

  12. Schools at the Rural-Urban Boundary - Blurring the Divide?

    Science.gov (United States)

    Burdick-Will, Julia; Logan, John R

    2017-07-01

    Schools mirror the communities in which they are located. Research on school inequality across the rural-urban spectrum tends to focus on the contrast between urban, suburban, and rural schools and glosses over the variation within these areas as well as the similarities between them. To address this gap and provide a richer description of the spatial distribution of educational inequality, we examine the school composition, achievement, and resources of all U.S. elementary schools in 2010-2011. We apply standard census definitions of what areas fall within central cities, the remainder of metropolitan regions, and in rural America. We then apply spatially explicit methods to reveal blurred boundaries and gradual gradients rather than sharp breaks at the edges of these zones. The results show high levels of variation within the suburbs and substantial commonality between rural and urban areas.

  13. Are single entry communities and cul-de-sacs a barrier to active transport to school in 11 elementary schools in Las Vegas, NV metropolitan area?

    Directory of Open Access Journals (Sweden)

    Courtney Coughenour

    2017-06-01

    Full Text Available Single entry communities (SECs and cul-de-sacs minimize route choices and increase trip distance. Las Vegas' built environment facilitates the examination of these variables and active transport to school (ATS rates. The purpose of this study was to examine the influence of SECs and cul-de-sacs on ATS rates in Las Vegas, NV elementary children. Parental-reported data was collected from 11 elementary schools on ATS rates (n = 1217. SECs and cul-de-sacs were quantified for each school zone. Logistic regression models were used to predict ATS. 23.9% of students reported ATS all of the time and 31.4% some of the time. SECs per school zone ranged from 0 to 25 (mean = 11.9. Cul-de-sacs ranged from 12 to 315 (mean = 138.3. Some ATS use was predicted by distance from school (p ≤ 0.001;OR = 0.61, parental education (high school: p = 0.004;OR = 0.53, some college: p = 0.001;OR = 0.50, 4 year degree: p = 0.004;OR = 0.52 and cul-de-sacs (p ≤ 0.001;OR = 0.99. A separate model using distance from school (p ≤ 0.001;OR = 0.61, parental education (high school: p = 0.002;OR = 0.51, some college: p ≤ 0.001;OR = 0.45, 4 year degree: p ≤ 0.001;OR = 0.45 and SECs (p ≤ 0.001;OR = 0.96 predicted some ATS. All ATS use was predicted by distance from school (p ≤ 0.001;OR = 0.58, parental education (Grades 9–11: p = 0.05;OR = 0.61, high school: p ≤ 0.001;OR = 0.45, some college: p ≤ 0.001;OR = 0.41, 4 year degree: p ≤ 0.001;OR = 0.38 and SECs (p ≤ 0.001;OR = 0.97. A separate model using distance from school (p ≤ 0.001;OR = 0.58, parental education (Grades 9–11: p = 0.041;OR = 0.59, high school: p ≤ 0.001;OR = 0.47, some college: p ≤ 0.001;OR = 0.44, 4 year degree: p ≤ 0.001;OR = 0.43 and cul-de-sacs (p ≤ 0.001;OR = 0.99 predicted all ATS. Current findings reveal that both SECs and cul-de-sacs were predictors of ATS beyond distance. Students

  14. 76 FR 44803 - Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation...

    Science.gov (United States)

    2011-07-27

    ... USCG-2009-1081 New Orleans, LA Safety Zone (Part 165)..... 12/23/2009 USCG-2009-1084 Rio Vista, CA...-1096 Port Portland Zone......... Safety Zone (Part 165)..... 7/3/2010 USCG-2009-0040 La Push, WA Safety...-0950 Madisonville, LA Safety Zone (Part 165)..... 12/31/2009 USCG-2009-0951 Lower Mississippi River...

  15. 14 CFR 25.1515 - Landing gear speeds.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Landing gear speeds. 25.1515 Section 25... Limitations § 25.1515 Landing gear speeds. (a) The established landing gear operating speed or speeds, V LO, may not exceed the speed at which it is safe both to extend and to retract the landing gear, as...

  16. Evaluating the Promise of Single-Track Year-Round Schools.

    Science.gov (United States)

    Haenn, Joseph F.

    1996-01-01

    Describes two single-track year-round elementary schools in Durham, North Carolina, established in discrete attendance zones. Remediation and enrichment activities were provided during intersession. Low-SES students were overrepresented in remediation sessions. Student outcomes data (end-of-grade reading and math test scores) suggest that…

  17. RADIATION ACCESS ZONE AND VENTILATION CONFINEMENT ZONE CRITERIA FOR THE MGR SURFACE FACILITIES

    International Nuclear Information System (INIS)

    D. A. Padula

    2000-01-01

    The objectives of this technical report are to: (1) Establish the criteria for Radiation Access Zone (RAZ) designation. (2) Establish the criteria for the Ventilation Confinement Zone (VCZ) designation. The scope will be to formulate the RAZ and VCZ zoning designation for the Monitored Geologic Repository (MGR) surface facilities and to apply the zoning designations to the current Waste Handling Building (WHB), Waste Treatment Building (WTB), and Carrier Preparation Building (CPB) configurations

  18. Speed limiter integrated fatigue analyzer (SLIFA) for speed and fatigue control on diesel engine truck and bus

    Science.gov (United States)

    Wahyudi, Haris; Pranoto, Hadi; Leman, A. M.; Sebayang, Darwin; Baba, I.

    2017-09-01

    Every second, the number of road traffic deaths is increased globally with millions more sustaining severe injuries and living with long-term adverse health consequences. Jakarta alone in year 2015 had recorded 556 people died due to road accidents, approximately reached 6.231 road accident cases. The identified major contributory factors of such unfortunate events are both driver fatigue and over speeding habit especially related to the driving of truck and bus. This paper presents the idea on how to control the electronic system from input fuel system of injection pump and the combustion chamber engine will control the valve solenoid in injection pump which can lock and fuel will stop for moment, and speed limit can be success, by using sensor heart rate we can input reduce speed limit when fatigue detection driver. Integration process this tool can be relevant when Speed Limiter Integrated Fatigue Analyser (SLIFA) trial in the diesel engine for truck and bus, the result of this research Speed Limiter Integrated Fatigue Analyser (SLIFA) able to control speed of diesel engine for truck and bus almost 30km/h, 60km/h, and until 70 km/h. The installation of the sensor heart rate as the input speed limit SLIFA would work when the driver is detected to be in the fatigue condition. We make Speed Limiter Integrated Fatigue Analyser (SLIFA) for control and monitoring system for diesel engine in truck and bus. Speed Limiter Integrated Fatigue Analyser (SLIFA) system can save the historical of the speed record, fatigue, rpm, and body temperature of the driver.

  19. Prevalence and Predictors of Intestinal Helminthiasis among School ...

    African Journals Online (AJOL)

    The objective of the survey was to determine the prevalence and predictors of intestinal parasitosis among school children in four woredas of Jimma zone surrounding Gilgel gibe hydraulic dam and serve as a base line data to help evaluate health promoting activities for the future and monitor those already delivered to the ...

  20. High-speed railways in Japan

    International Nuclear Information System (INIS)

    Kyotani, Y.

    1974-01-01

    This paper reviews the development of conventional railways in Japan, leading up to the Shinkansen line, which at present runs at speeds up to 210km/h, and will in the future be speeded up to 260km/h. It then goes on to review the development of a superconductive, magnetically levitated train, which will constitute the next generation of railways, running at speeds of up to 500km/h. (author)

  1. Endurance in speed skating

    NARCIS (Netherlands)

    Kuper, G.H.; Sterken, E.

    2002-01-01

    We analyse the development of world records speed skating from 1893 to 2000 for bothmen and women. The historical data show that it is likely that the relation betweenskating speed and distance of the various events is non-linear and converges to a limitvalue. We pay special attention to technical

  2. 76 FR 8917 - Special Conditions: Gulfstream Model GVI Airplane; Automatic Speed Protection for Design Dive Speed

    Science.gov (United States)

    2011-02-16

    ... high speed protection system. These proposed special conditions contain the additional safety standards... Design Features The GVI is equipped with a high speed protection system that limits nose down pilot... incorporation of a high speed protection system in the GVI flight control laws. The GVI is equipped with a high...

  3. Dietary Factors Associated To Obesity In Ahwaz Primary School Pupils

    Directory of Open Access Journals (Sweden)

    Dorosty A.R; Tabatabaei M

    2005-05-01

    Full Text Available Background: Increase in obesity prevalence in recent years are associated to genetics as well environmental and behavioral factors. Change in dietary patterns including fatty and high density energy foods consumption have been reported to be very important. This study aimed to determine dietary factors (daily energy and macronutrient intakes, energy percentage of macronutrient, energy and macronutrient intakes per kilogram body weight, frequency of cola, natural fruit juice drinking, dairy products except cheese, tomato chips, puff, chocolate and fast food consumption and eating speed associated to obesity in Ahwaz primary school pupils. Materials and Methods: Using two stage cluster sampling from 35 Ahwaz primary schools, all 10-11y students who had a BMI 95th percentile of Hosseini et al. (1999 reference, were identified as obese (n=150 and 150 same age and gender pupils (having BMI0.05. macronutrient intakes per kilogram body weight were significantly lower in obese group (p0.05. Obese students used to eat faster (p<0.05. Conclusion: In conclusion, high intakes of energy, protein, carbohydrate, tomato chips and puff and high eating speed were associated to obesity in Ahwaz primary school pupils.

  4. School Integration Program in Chile: gaps and challenges for the implementation of an inclusive education program

    Directory of Open Access Journals (Sweden)

    Mauro Tamayo Rozas

    2018-06-01

    Full Text Available Constructing inclusive societies, leaving no one behind, it is an ethical obligation. Developing inclusive educational programs allows ensuring equal opportunities in one of the most critical stages of development. The aim of this study is to describe the implementation of the School Integration Program (SIP in its different dimensions and in different zones of Chile. A descriptive and cross-sectional study of the perception of SIP Coordinators was performed in public and subsidized schools at the country through a web-based survey. A simple random convenience sampling of schools was performed, obtaining 1742 answers from educational establishments with SIP. Higher level of implementation of the program was identified in areas related to interdisciplinary work and comprehensive training, curricular and institutional aspects. On the other hand, deficiencies were identified in the implementation of accessibility, development of reasonable adjustments and participation of the educational community. Likewise, there are differences between the zones of Chile, with the North zone having the least progress. Although there are results in the work team and institutional development, the development of objective conditions and participation is still a pending task in the implementation of the SIP.

  5. Influence of tool geometry and rotational speed on mechanical properties and defect formation in friction stir lap welded 5456 aluminum alloy sheets

    International Nuclear Information System (INIS)

    Salari, Emad; Jahazi, Mohammad; Khodabandeh, Alireza; Ghasemi-Nanesa, Hadi

    2014-01-01

    Highlights: • Successful lap joint friction stir welding of AA5456 with two different tempers. • New stepped conical threaded pin for FSW of lap joints is introduced. • Investigated interactions between tool geometry and mechanical properties. • Microstructure and fracture surface analysis of dissimilar lap welds. - Abstract: Friction stir welding of AA5456 aluminum alloy in lap joint configuration is with two different tempers, T321 and O, and different thicknesses, 5 mm and 2.5 mm was investigated. The influences of tool geometry and various rotational speeds on macrostructure, microstructure and joint strength are presented. Specifically, four different tool pin profiles (a conical thread pin, a cylindrical–conical thread pin, a stepped conical thread pin and Flared Triflute pin tool) and two rotational speeds, 600 and 800 rpm, were used. The results indicated that, tool geometry influences significantly material flow in the nugget zone and accordingly control the weld mechanical properties. Of particular interest is the stepped conical threaded pin, which is introduced for the first time in the present investigation. Scanning electron microscopy investigation of the fracture location of samples was carried out and the findings correlated with tool geometry features and their influences on material flow and tension test results. The optimum microstructure and mechanical properties were obtained for the joints produced with the stepped conical thread pin profile and rotational speed of 600 rpm. The characteristics of the nugget zone microstructure, hooking height, and fracture location of the weld joints were used as criteria to quantify the influence of processing conditions on joint performance and integrity. The results are interpreted in the framework of physical metallurgy properties and compared with published literature

  6. Endurance in speed skating

    NARCIS (Netherlands)

    Kuper, Gerard H.; Sterken, Elmer

    2001-01-01

    We analyse the development of world records speed skating from 1893 to 2000 for both men and women. The historical data show that it is likely that the relation between skating speed and distance of the various events is non-linear and converges to a limit value. We pay special attention to

  7. Hanford Site peak gust wind speeds

    International Nuclear Information System (INIS)

    Ramsdell, J.V.

    1998-01-01

    Peak gust wind data collected at the Hanford Site since 1945 are analyzed to estimate maximum wind speeds for use in structural design. The results are compared with design wind speeds proposed for the Hanford Site. These comparisons indicate that design wind speeds contained in a January 1998 advisory changing DOE-STD-1020-94 are excessive for the Hanford Site and that the design wind speeds in effect prior to the changes are still appropriate for the Hanford Site

  8. Visual processing speed in old age

    DEFF Research Database (Denmark)

    Habekost, Thomas; vogel, asmus; Rostrup, Egill

    2013-01-01

    of the speed of a particular psychological process that are not confounded by the speed of other processes. We used Bundesen's (1990) Theory of Visual Attention (TVA) to obtain specific estimates of processing speed in the visual system controlled for the influence of response latency and individual variations...... dramatic aging effects were found for the perception threshold and the visual apprehension span. In the visual domain, cognitive aging seems to be most clearly related to reductions in processing speed....

  9. Handwriting assessment of Franco-Quebec primary school-age students

    Science.gov (United States)

    Couture, Mélanie; Morin, Marie-France; Coallier, Mélissa; Lavigne, Audrey; Archambault, Patricia; Bolduc, Émilie; Chartier, Émilie; Liard, Karolane; Jasmin, Emmanuelle

    2016-12-01

    Reasons for referring school-age children to occupational therapy mainly relate to handwriting problems. However, there are no validated tools or reference values for assessing handwriting in francophone children in Canada. This study aimed to adapt and validate the writing tasks described in an English Canadian handwriting assessment protocol and to develop reference values for handwriting speed for francophone children. Three writing tasks from the Handwriting Assessment Protocol-2nd Edition (near-point and far-point copying and dictation) were adapted for Québec French children and administered to 141 Grade 1 ( n = 73) and Grade 2 ( n = 68) students. Reference values for handwriting speed were obtained for near point and far point copying tasks. This adapted protocol and these reference values for speed will improve occupational therapy handwriting assessments for the target population.

  10. GIS as a Tool for Education Decision Support System: A Demonstration with Public Primary Schools in Zaria City Kaduna State Nigeria

    Directory of Open Access Journals (Sweden)

    U. Wali

    2015-07-01

    Full Text Available This paper aimed at demonstrating the use of GIS in the display of data about primary schools in the walled part of Zaria city, Kaduna State. It is hoped that the database and its graphic display in maps will guide decision making at the primary education level in the study area. Coordinates of the schools were obtained with a handheld GPS receiver, while their attribute data were obtained from the local education authority and triangulated with questionnaires administered to the headmasters of the schools. ArcGIS 9.2 version software was used for buffer zone (1 km. The result indicates that there are 31 public primary schools in the study area. The oldest was established in 1921 and the latest in 2007. Graphic displays of some attributes of the schools were produced. The buffer zones produced suggest no pupil walks more than a kilometer to reach school. It is recommended that in the future, GIS tools should be applied when managing school data. Capacities to achieve this should be developed.

  11. 33 CFR 165.1315 - Safety Zones: Fireworks displays in the Captain of the Port Portland Zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zones: Fireworks displays... Coast Guard District § 165.1315 Safety Zones: Fireworks displays in the Captain of the Port Portland Zone. (a) Safety zones. The following areas are designated safety zones: (1) Cinco de Mayo Fireworks...

  12. 14 CFR 25.253 - High-speed characteristics.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false High-speed characteristics. 25.253 Section...-speed characteristics. (a) Speed increase and recovery characteristics. The following speed increase and recovery characteristics must be met: (1) Operating conditions and characteristics likely to cause...

  13. The Impact of High-Speed Rail on Residents’ Travel Behavior and Household Mobility: A Case Study of the Beijing-Shanghai Line, China

    Directory of Open Access Journals (Sweden)

    Hongsheng Chen

    2016-11-01

    Full Text Available With the improvement of China’s high-speed rail network, there have been many economic and social benefits for local residents. Based on a questionnaire conducted in stations on the Beijing-Shanghai line, and through an analysis of high-speed rail passenger travel behavior and family relocation, we explored the social effects of high-speed rail. The study found that high-speed rail passengers are mainly young, highly educated, and have a middle to high income. However, with the popularization of high-speed rail, such differences in the social stratum of high-speed rail passengers are expected to disappear. Through an analysis of passenger travel status, we found that the areas surrounding high-speed rail stations are very accessible to the main cities, and are well connected by other public transport. With the emergence of the “high mobility era” based on the high-speed rail network, the separation of workplace and residence and the number of “double city” households are increasing, primarily in the Beijing-Tianjin and Shanghai-Nanjing (especially in Suzhou-Kunshan-Shanghai regions. In addition, high-speed rail introduces the possibility of household mobility, with 22.7% of the respondents in this study having relocated since the Beijing-Shanghai line opened. Household mobility is apparent primarily among big cities, with movement toward nearby cities. We also found that occupation, income, residence time, and schooling of children have a significant impact on households. With the improvement of high-speed rail networks, household mobility will become a common phenomenon and research on domestic mobility will continue to increase.

  14. Systems and methods for vehicle speed management

    Science.gov (United States)

    Sujan, Vivek Anand; Vajapeyazula, Phani; Follen, Kenneth; Wu, An; Forst, Howard Robert

    2016-03-01

    Controlling a speed of a vehicle based on at least a portion of a route grade and a route distance divided into a plurality of route sections, each including at least one of a section grade and section length. Controlling the speed of the vehicle is further based on determining a cruise control speed mode for the vehicle for each of the plurality of route sections and determining a speed reference command of the vehicle based on at least one of the cruise control speed mode, the section length, the section grade, and a current speed.

  15. Surface grinding characteristics of ferrous metals under high-speed and speed-stroke grinding conditions

    International Nuclear Information System (INIS)

    Ghani, A.K.; Choudhury, I.A.; Ahim, M.B.

    1999-01-01

    Some ferrous metals have been ground under different conditions with high-speed and speed-stroke in surface grinding operation. The paper describes experimental investigation of grinding forces in grinding some ferrous metals with the application of cutting fluids. Grinding tests have been carried out on mild steel, assab steel and stainless steel with different combinations of down feed and cross feed. The wheel speed was 27 m/sec while the table speed was maintained at the maximum possible 25 m/min. The grindability has been evaluated by measuring the grinding forces, grinding ratio, and surface finish. Grinding forces have been plotted against down feed of the grinding wheel and cross feed of the table. It has been observed that the radial and tangential grinding forces in stainless steel were higher than those in assab steel and mild steel

  16. Executive Function in Very Preterm Children at Early School Age

    NARCIS (Netherlands)

    C.S.H. Aarnoudse-Moens (Cornelieke); D.P. Smidts (Diana); J. Oosterlaan (Jaap); H.J. Duivenvoorden (Hugo); N. Weisglas-Kuperus (Nynke)

    2009-01-01

    textabstractWe examined whether very preterm (≤30 weeks gestation) children at early school age have impairments in executive function (EF) independent of IQ and processing speed, and whether demographic and neonatal risk factors were associated with EF impairments. A consecutive sample of 50

  17. Network Design: Best Practices for Alberta School Jurisdictions.

    Science.gov (United States)

    Schienbein, Ralph

    This report examines subsections of the computer network topology that relate to end-to-end performance and capacity planning in schools. Active star topology, Category 5 wiring, Ethernet, and intelligent devices are assumed. The report describes a model that can be used to project WAN (wide area network) connection speeds based on user traffic,…

  18. Improving homogeneity by dynamic speed limit systems.

    NARCIS (Netherlands)

    Nes, N. van Brandenberg, S. & Twisk, D.A.M.

    2010-01-01

    Homogeneity of driving speeds is an important variable in determining road safety; more homogeneous driving speeds increase road safety. This study investigates the effect of introducing dynamic speed limit systems on homogeneity of driving speeds. A total of 46 subjects twice drove a route along 12

  19. 77 FR 30245 - Safety Zones; Annual Fireworks Events in the Captain of the Port Detroit Zone

    Science.gov (United States)

    2012-05-22

    ...'' N, 082-51'-18.70'' W (NAD 83). This proposed zone would be enforced one evening during the last week...-AA00 Safety Zones; Annual Fireworks Events in the Captain of the Port Detroit Zone AGENCY: Coast Guard... by adding three permanent safety zones within the Captain of the Port Detroit Zone. This action is...

  20. Blind haste: As light decreases, speeding increases.

    Science.gov (United States)

    de Bellis, Emanuel; Schulte-Mecklenbeck, Michael; Brucks, Wernher; Herrmann, Andreas; Hertwig, Ralph

    2018-01-01

    Worldwide, more than one million people die on the roads each year. A third of these fatal accidents are attributed to speeding, with properties of the individual driver and the environment regarded as key contributing factors. We examine real-world speeding behavior and its interaction with illuminance, an environmental property defined as the luminous flux incident on a surface. Drawing on an analysis of 1.2 million vehicle movements, we show that reduced illuminance levels are associated with increased speeding. This relationship persists when we control for factors known to influence speeding (e.g., fluctuations in traffic volume) and consider proxies of illuminance (e.g., sight distance). Our findings add to a long-standing debate about how the quality of visual conditions affects drivers' speed perception and driving speed. Policy makers can intervene by educating drivers about the inverse illuminance‒speeding relationship and by testing how improved vehicle headlights and smart road lighting can attenuate speeding.

  1. Blind haste: As light decreases, speeding increases.

    Directory of Open Access Journals (Sweden)

    Emanuel de Bellis

    Full Text Available Worldwide, more than one million people die on the roads each year. A third of these fatal accidents are attributed to speeding, with properties of the individual driver and the environment regarded as key contributing factors. We examine real-world speeding behavior and its interaction with illuminance, an environmental property defined as the luminous flux incident on a surface. Drawing on an analysis of 1.2 million vehicle movements, we show that reduced illuminance levels are associated with increased speeding. This relationship persists when we control for factors known to influence speeding (e.g., fluctuations in traffic volume and consider proxies of illuminance (e.g., sight distance. Our findings add to a long-standing debate about how the quality of visual conditions affects drivers' speed perception and driving speed. Policy makers can intervene by educating drivers about the inverse illuminance‒speeding relationship and by testing how improved vehicle headlights and smart road lighting can attenuate speeding.

  2. Pulse-Like Rupture Induced by Three-Dimensional Fault Zone Flower Structures

    KAUST Repository

    Pelties, Christian

    2014-07-04

    © 2014, Springer Basel. Faults are often embedded in low-velocity fault zones (LVFZ) caused by material damage. Previous 2D dynamic rupture simulations (Huang and Ampuero, 2011; Huang et al., 2014) showed that if the wave velocity contrast between the LVFZ and the country rock is strong enough, ruptures can behave as pulses, i.e. with local slip duration (rise time) much shorter than whole rupture duration. Local slip arrest (healing) is generated by waves reflected from the LVFZ–country rock interface. This effect is robust against a wide range of fault zone widths, absence of frictional healing, variation of initial stress conditions, attenuation, and off-fault plasticity. These numerical studies covered two-dimensional problems with fault-parallel fault zone structures. Here, we extend previous work to 3D and geometries that are more typical of natural fault zones, including complexities such as flower structures with depth-dependent velocity and thickness, and limited fault zone depth extent. This investigation requires high resolution and flexible mesh generation, which are enabled here by the high-order accurate arbitrary high-order derivatives discontinuous Galerkin method with an unstructured tetrahedral element discretization (Peltieset al., 2012). We show that the healing mechanism induced by waves reflected in the LVFZ also operates efficiently in such three-dimensional fault zone structures and that, in addition, a new healing mechanism is induced by unloading waves generated when the rupture reaches the surface. The first mechanism leads to very short rise time controlled by the LVFZ width to wave speed ratio. The second mechanism leads to generally longer, depth-increasing rise times, is also conditioned by the existence of an LVFZ, and persists at some depth below the bottom of the LVFZ. Our simulations show that the generation of slip pulses by these two mechanisms is robust to the depth extent of the LVFZ and to the position of the hypocenter

  3. Visual processing speed in old age.

    Science.gov (United States)

    Habekost, Thomas; Vogel, Asmus; Rostrup, Egill; Bundesen, Claus; Kyllingsbaek, Søren; Garde, Ellen; Ryberg, Charlotte; Waldemar, Gunhild

    2013-04-01

    Mental speed is a common concept in theories of cognitive aging, but it is difficult to get measures of the speed of a particular psychological process that are not confounded by the speed of other processes. We used Bundesen's (1990) Theory of Visual Attention (TVA) to obtain specific estimates of processing speed in the visual system controlled for the influence of response latency and individual variations of the perception threshold. A total of 33 non-demented old people (69-87 years) were tested for the ability to recognize briefly presented letters. Performance was analyzed by the TVA model. Visual processing speed decreased approximately linearly with age and was on average halved from 70 to 85 years. Less dramatic aging effects were found for the perception threshold and the visual apprehension span. In the visual domain, cognitive aging seems to be most clearly related to reductions in processing speed. © 2012 The Authors. Scandinavian Journal of Psychology © 2012 The Scandinavian Psychological Associations.

  4. Second-generation speed limit map updating applications

    DEFF Research Database (Denmark)

    Tradisauskas, Nerius; Agerholm, Niels; Juhl, Jens

    2011-01-01

    Intelligent Speed Adaptation is an Intelligent Transport System developed to significantly improve road safety in helping car drivers maintain appropriate driving behaviour. The system works in connection with the speed limits on the road network. It is thus essential to keep the speed limit map...... used in the Intelligent Speed Adaptation scheme updated. The traditional method of updating speed limit maps on the basis of long time interval observations needed to be replaced by a more efficient speed limit updating tool. In a Danish Intelligent Speed Adaptation trial a web-based tool was therefore...... for map updating should preferably be made on the basis of a commercial map provider, 2 such as Google Maps and that the real challenge is to oblige road authorities to carry out updates....

  5. Association between junk food consumption and fast-food outlet access near school among Quebec secondary-school children: findings from the Quebec Health Survey of High School Students (QHSHSS) 2010-11.

    Science.gov (United States)

    Cutumisu, Nicoleta; Traoré, Issouf; Paquette, Marie-Claude; Cazale, Linda; Camirand, Hélène; Lalonde, Benoit; Robitaille, Eric

    2017-04-01

    We investigated the association between junk food consumption at lunchtime (JCL) and fast-food outlet access near school among secondary-school children in Quebec. A geographic information system database was used to characterize the food environment around a sub-sample of 374 public schools in which 26 655 students were enrolled. The outcome variable was JCL during the previous week, dichotomized into low JCL (none or once) v. high JCL (twice or more). Access to fast-food outlets near school was assessed using an existing database of fast-food outlets in Quebec. Covariates included student (age, sex and self-rated perceived health), family (familial status and parental education) and school (urban/rural status and deprivation) variables. Hierarchical logistic regression models were employed for analyses using PROC GLIMMIX of SAS version 9.3. Province of Quebec, Canada. We used data from the Quebec Health Survey of High School Students (QHSHSS) 2010-11, a survey of secondary-school Quebec students. Exposure to two or more fast-food outlets within a radius of 750 m around schools was associated with a higher likelihood of excess JCL (OR=1·50; 95 % CI 1·28, 1·75), controlling for the characteristics of the students, their families and their schools. The food environment surrounding schools can constitute a target for interventions to improve food choices among secondary-school children living in the province of Quebec. Transforming environments around schools to promote healthy eating includes modifying zoning regulations that restrict access to fast-food outlets around schools.

  6. Speed Optimization in Liner Shipping Network Design

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Karsten, Christian Vad; Pisinger, David

    In the Liner Shipping Network Design Problem (LSNDP) services sail at a given speed throughout a round trip. In reality most services operate with a speed differentiated head- and back-haul, or even individual speeds on every sailing between two ports. The speed of a service is decisive...

  7. Schools at the Rural-Urban Boundary – Blurring the Divide?

    Science.gov (United States)

    Burdick-Will, Julia; Logan, John R.

    2018-01-01

    Schools mirror the communities in which they are located. Research on school inequality across the rural-urban spectrum tends to focus on the contrast between urban, suburban, and rural schools and glosses over the variation within these areas as well as the similarities between them. To address this gap and provide a richer description of the spatial distribution of educational inequality, we examine the school composition, achievement, and resources of all U.S. elementary schools in 2010–2011. We apply standard census definitions of what areas fall within central cities, the remainder of metropolitan regions, and in rural America. We then apply spatially explicit methods to reveal blurred boundaries and gradual gradients rather than sharp breaks at the edges of these zones. The results show high levels of variation within the suburbs and substantial commonality between rural and urban areas. PMID:29430017

  8. Hourly wind speed analysis in Sicily

    Energy Technology Data Exchange (ETDEWEB)

    Bivona, S.; Leone, C. [Palermo Univ., Dip di Fisica e Technologie Relative, Palermo (Italy); Burlon, R. [Palermo Univ., Dip. di Ingegnaria Nucleare, Palermo (Italy)

    2003-07-01

    The hourly average wind speed data recorded by CNMCA (Centro Nazionale di Meteorologia e Climatologia Aeronautica) have been used to study the statistical properties of the wind speed at nine locations on Sicily. By grouping the observations month by month, we show that the hourly average wind speed, with calms omitted, is represented by a Weibull function. The suitability of the distribution is judged by the discrepancies between the observed and calculated values of the monthly average wind speed and of the standard deviation. (Author)

  9. 33 CFR 165.503 - Security Zone; Captain of the Port Hampton Roads Zone.

    Science.gov (United States)

    2010-07-01

    ... Port Hampton Roads Zone. 165.503 Section 165.503 Navigation and Navigable Waters COAST GUARD... § 165.503 Security Zone; Captain of the Port Hampton Roads Zone. (a) Definitions. As used in this... been authorized by the Captain of the Port (COTP), Hampton Roads, Virginia to act on his or her behalf...

  10. Effects of optical diagnostic techniques on the accuracy of laminar flame speeds measured from Bunsen flames: OH* chemiluminescence, OH-PLIF and acetone/kerosene-PLIF

    Science.gov (United States)

    Wu, Yi; Modica, Vincent; Yu, Xilong; Li, Fei; Grisch, Frédéric

    2018-01-01

    The effects of optical diagnostic techniques on the accuracy of laminar flame speed measured from Bunsen flames were investigated. Laminar flame speed measurements were conducted for different fuel/air mixtures including CH4/air, acetone/air and kerosene (Jet A-1)/air in applying different optical diagnostic techniques, i.e. OH* chemiluminescence, OH-PLIF and acetone/kerosene-PLIF. It is found that the OH* chemiluminescence imaging technique cannot directly derive the location of the outer edge of the fresh gases and it is necessary to correct the position of the OH* peak to guarantee the accuracy of the measurements. OH-PLIF and acetone/kerosene-PLIF respectively are able to measure the disappearance of the fresh gas contour and the appearance of the reaction zone. It shows that the aromatic-PLIF technique gives similar laminar flame speed values when compared with those obtained from corrected OH* chemiluminescence images. However, discrepancies were observed between the OH-PLIF and the aromatic-PLIF techniques, in that OH-PLIF slightly underestimates laminar flame speeds by up to 5%. The difference between the flame contours obtained from different optical techniques are further analysed and illustrated with 1D flame structure simulation using detailed kinetic mechanisms.

  11. Dynamic magneto-optical imaging of transport current redistribution and normal zone propagation in YBa2Cu3O7-δ coated conductor

    International Nuclear Information System (INIS)

    Song Honghai; Schwartz, Justin; Davidson, Michael W

    2009-01-01

    YBa 2 Cu 3 O 7-δ (YBCO) coated conductors carry high critical current density with the potential for low cost and thus have a broad range of potential applications. An unresolved issue that could inhibit implementation, however, is a lack of understanding of the current redistribution and normal zone propagation behavior in the event of a thermal disturbance (quench). In this work, we for the first time present the real-time, dynamic observation of magnetic field redistribution during a thermal disturbance via magneto-optical imaging with a high speed, high resolution CCD (charge coupled device) camera. The optical images are converted to a two-dimensional, time-dependent data set that is then analyzed quantitatively. It is found that the normal zone propagates non-uniformly in two dimensions within the YBCO layer. Two stages of normal zone propagation are observed. During the first stage, the normal zone propagates along the conductor length as the current and magnetic field redistribute within the YBCO layer. During the second stage, current sharing with the Cu begins and the magneto-optical image becomes constant. The normal zone propagation velocity at 45 K, I = 50 A (∼50% I c ), is determined as 22.7 mm s -1 using the time-dependent optical light intensity data. (rapid communication)

  12. 14 CFR 23.253 - High speed characteristics.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false High speed characteristics. 23.253 Section... Requirements § 23.253 High speed characteristics. If a maximum operating speed VMO/MMO is established under § 23.1505(c), the following speed increase and recovery characteristics must be met: (a) Operating...

  13. Formulating a coastal zone health metric for landuse impact management in urban coastal zones.

    Science.gov (United States)

    Anilkumar, P P; Varghese, Koshy; Ganesh, L S

    2010-11-01

    The need for ICZM arises often due to inadequate or inappropriate landuse planning practices and policies, especially in urban coastal zones which are more complex due to the larger number of components, their critical dimensions, attributes and interactions. A survey of literature shows that there is no holistic metric for assessing the impacts of landuse planning on the health of a coastal zone. Thus there is a need to define such a metric. The proposed metric, CHI (Coastal zone Health Indicator), developed on the basis of coastal system sustainability, attempts to gauge the health status of any coastal zone. It is formulated and modeled through an expert survey and pertains to the characteristic components of coastal zones, their critical dimensions, and relevant attributes. The proposed metric is applied to two urban coastal zones and validated. It can be used for more coast friendly and sustainable landuse planning/masterplan preparation and thereby for the better management of landuse impacts on coastal zones. Copyright 2010 Elsevier Ltd. All rights reserved.

  14. Speed Biases With Real-Life Video Clips

    Directory of Open Access Journals (Sweden)

    Federica Rossi

    2018-03-01

    Full Text Available We live almost literally immersed in an artificial visual world, especially motion pictures. In this exploratory study, we asked whether the best speed for reproducing a video is its original, shooting speed. By using adjustment and double staircase methods, we examined speed biases in viewing real-life video clips in three experiments, and assessed their robustness by manipulating visual and auditory factors. With the tested stimuli (short clips of human motion, mixed human-physical motion, physical motion and ego-motion, speed underestimation was the rule rather than the exception, although it depended largely on clip content, ranging on average from 2% (ego-motion to 32% (physical motion. Manipulating display size or adding arbitrary soundtracks did not modify these speed biases. Estimated speed was not correlated with estimated duration of these same video clips. These results indicate that the sense of speed for real-life video clips can be systematically biased, independently of the impression of elapsed time. Measuring subjective visual tempo may integrate traditional methods that assess time perception: speed biases may be exploited to develop a simple, objective test of reality flow, to be used for example in clinical and developmental contexts. From the perspective of video media, measuring speed biases may help to optimize video reproduction speed and validate “natural” video compression techniques based on sub-threshold temporal squeezing.

  15. Using SST and land cover data from EO Missions for improved mesoscale modelling of the coastal zone

    DEFF Research Database (Denmark)

    Karagali, Ioanna; Floors, Rogier Ralph; Lea, Guillaume

    was to evaluate the uncertainty of the modelled wind in the coastal zone and further improve it. Moreover LIDAR measurements were used to evaluate the wind speed retrieval from high resolution SAR systems (Sentinel-1 and TerraSAR-X). The WRF model used a high-resolution satellite SST reanalysis product from...... be implemented in the meso-scale model to better represent the actual conditions in the study area. Such improvements are expected to strengthen the model’s ability to represent land- sea and air-sea interactions, the atmospheric stability and the local topographic features that partly affect the coastal zone......Existing wind measurements in near-shore and offshore areas are sparse and scarce, therefore simulations from state-of-the-art meso-scale models are used for wind resource predictions. In coastal and near-shore areas, models are inaccurate and uncertain, mainly because of numerical approximations...

  16. 77 FR 6007 - Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation...

    Science.gov (United States)

    2012-02-07

    ...] Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation... they could be published in the Federal Register. This notice lists temporary safety zones, security... the safety and security needs within their jurisdiction; therefore, District Commanders and COTPs have...

  17. Assessing the Desired and Actual Levels of Teachers' Participation in Decision-Making in Secondary Schools of Ethiopia

    Science.gov (United States)

    Bademo, Yismaw; Tefera, Bekalu Ferede

    2016-01-01

    This study was conducted to assess the desired and actual levels of teachers' participation in decision-making process in Ethiopian secondary schools. For this, the study employed a cross-sectional survey design collecting data from sampled secondary school teachers (n = 258) found in Assosa Zone, Benishangual Gumuz Regional state, Ethiopia.…

  18. 78 FR 26508 - Safety Zone; Fireworks Event in Captain of the Port New York Zone

    Science.gov (United States)

    2013-05-07

    ... Harbor located in approximate Safety Zone, 33 CFR 165.160(3.8). position 40[deg]51'58'' N, 073[deg]39'34... Zone; Fireworks Event in Captain of the Port New York Zone AGENCY: Coast Guard, DHS. ACTION: Notice of enforcement of regulation. SUMMARY: The Coast Guard will enforce safety zones in the Captain of the Port New...

  19. The distinguishing characteristics of interlayer oxidation zone and burial ancient ground oxidation zone

    International Nuclear Information System (INIS)

    Zhang Zhanshi; Zhou Wenbin

    1998-01-01

    The author discusses the main characteristics of interlayer oxidation zones and the burial ancient ground oxidation zones of Uranium deposit No. 512 in Xinjiang Uigur municipality. The epigenetic genesis, depending on some aquifer, the tongue-like in section, having the zonation along dip direction and having certain mineral assemblage are the typical features for interlayer oxidation zones

  20. Zoning Districts - Volusia County HUB Zones

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Historically Underutilized Business (HUB) Zones in Volusia County. Go to http://www.sba.gov/hubzone or contact the Department of Economic Development (386) 248-8048...

  1. VT Data - Zoning 20120709, Huntington

    Data.gov (United States)

    Vermont Center for Geographic Information — Zoning district data for the Town of Huntington, Vermont. For details regarding each zoning district refer to the current zoning regulations on town of Huntington's...

  2. Does Extensive Reading Promote Reading Speed?

    Science.gov (United States)

    He, Mu

    2014-01-01

    Research has shown a wide range of learning benefits accruing from extensive reading. Not only is there improvement in reading, but also in a wide range of language uses and areas of language knowledge. However, few research studies have examined reading speed. The existing literature on reading speed focused on students' reading speed without…

  3. A tuberculin skin test survey among Ghanaian school children.

    Science.gov (United States)

    Addo, Kennedy Kwasi; van den Hof, Susan; Mensah, Gloria Ivy; Hesse, Adukwei; Bonsu, Christian; Koram, Kwadwo Ansah; Afutu, Felix Kwami; Bonsu, Frank Adae

    2010-01-26

    Ghana has not conducted a national tuberculin survey or tuberculosis prevalence survey since the establishment of the National Tuberculosis Control Programme. The primary objective of this study was therefore to determine the prevalence of tuberculin skin sensitivity in Ghanaian school children aged 6-10 years in 8 out of 10 regions of Ghana between 2004 and 2006. Tuberculin survey was conducted in 179 primary schools from 21 districts in 8 regions. Schools were purposively selected so as to reflect the proportion of affluent private and free tuition public schools as well as the proportion of small and large schools. Of the 24,778 children registered for the survey, 23,600 (95.2%) were tested of which 21,861 (92.6%) were available for reading. The age distribution showed an increase in numbers of children towards older age: 11% of the children were 6 years and 25%, 10 years. Females were 52.5% and males 47.5%. The proportion of girls was higher in all age groups (range 51.4% to 54.0%, p < 0.001). BCG scar was visible in 89.3% of the children. The percentage of children with a BCG scar differed by district and by age. The percentage of children with a BCG scar decreased with increasing age in all districts, reflecting increasing BCG vaccination coverage in Ghana in the last ten years. The risk of tuberculosis infection was low in the northern savannah zones compared to the southern coastal zones. Using a cut-off of 15 mm, the prevalence of infection ranged from 0.0% to 5.4% and the Annual Risks of Tuberculosis Infection 0.0% to 0.6%. There was an increase in the proportion of infected children after the age of 7 years. Children attending low and middle-class schools had a higher risk of infection than children attending upper-class schools. Tuberculosis infection is still a public health problem in Ghana and to monitor the trend, the survey needs to be repeated at 5 years interval.

  4. The effects of Nordic school meals on concentration and school performance in 8- to 11-year-old children in the OPUS School Meal Study: a cluster-randomised, controlled, cross-over trial.

    Science.gov (United States)

    Sørensen, Louise B; Dyssegaard, Camilla B; Damsgaard, Camilla T; Petersen, Rikke A; Dalskov, Stine-Mathilde; Hjorth, Mads F; Andersen, Rikke; Tetens, Inge; Ritz, Christian; Astrup, Arne; Lauritzen, Lotte; Michaelsen, Kim F; Egelund, Niels

    2015-04-28

    It is widely assumed that nutrition can improve school performance in children; however, evidence remains limited and inconclusive. In the present study, we investigated whether serving healthy school meals influenced concentration and school performance of 8- to 11-year-old Danish children. The OPUS (Optimal well-being, development and health for Danish children through a healthy New Nordic Diet) School Meal Study was a cluster-randomised, controlled, cross-over trial comparing a healthy school meal programme with the usual packed lunch from home (control) each for 3 months (NCT 01457794). The d2 test of attention, the Learning Rating Scale (LRS) and standard tests on reading and mathematics proficiency were administered at baseline and at the end of each study period. Intervention effects were evaluated using hierarchical mixed models. The school meal intervention did not influence concentration performance (CP; primary outcome, n 693) or processing speed; however, the decrease in error percentage was 0·18 points smaller (Pschool year. The percentage of correct sentences also improved (Pperformance or outcomes from the LRS. In conclusion, school meals did not affect CP, but improved reading performance, which is a complex cognitive activity that involves inference, and increased errors related to impulsivity and inattention. These findings are worth examining in future trials.

  5. Evaluating Speed Enforcement Field Set-Ups Used by Regional Police in Belgium: An Analysis of Speed Outcome Indicators

    Directory of Open Access Journals (Sweden)

    Brenda Wilmots

    2016-12-01

    Full Text Available In this paper the results from a field experiment (conducted in 2012 are presented, in which 3 regional police units in the Flemish region of Belgium each tested a particular combination of a speed control (with mobile radar in an anonymous car with communicative signage. The goal of this paper was to scientifically evaluate frequently used field set-ups. The following set-ups were tested in one week: (1 police unit 1: speed control with and without a static feedback sign placed after the control; (2 police unit 2: speed control with and without a digital feedback sign placed after the control; (3 police unit 3: speed display followed by a second speed display further along the road section. During certain time frames, speed control took place in between both signs. All tested field set-ups generated significant reductions in the speed level. Studying the effect of the different variations for each set-up reveals that the effect of the speed control is generally larger in combination with the signage alongside the road. After the period during which the police activities took place, speed levels again reached their initial level. Based on the before–after analysis, only in police area 2 was a small ‘time halo-effect’ found. To generalize results from this pilot study, repetition of tested set-ups in the field is recommended as well as testing on a larger scale.

  6. Reading Speed of Contracted French Braille

    Science.gov (United States)

    Laroche, Louise; Boule, Jacinthe; Wittich, Walter

    2012-01-01

    This study was designed to address three hypotheses: (1) The reading speed of both readers of French braille and readers of French print will be faster in the silent condition; however, this gain in speed will be larger for print readers; (2) Individuals who acquired braille before age 10 will display faster reading speeds at lower error rates…

  7. Wind speed estimation using multilayer perceptron

    International Nuclear Information System (INIS)

    Velo, Ramón; López, Paz; Maseda, Francisco

    2014-01-01

    Highlights: • We present a method for determining the average wind speed using neural networks. • We use data from that site in the short term and data from other nearby stations. • The inputs used in the ANN were wind speed and direction data from a station. • The method allows knowing the wind speed without topographical data. - Abstract: Wind speed knowledge is prerequisite in the siting of wind turbines. In consequence the wind energy use requires meticulous and specified knowledge of the wind characteristics at a location. This paper presents a method for determining the annual average wind speed at a complex terrain site by using neural networks, when only short term data are available for that site. This information is useful for preliminary calculations of the wind resource at a remote area having only a short time period of wind measurements measurement in a site. Artificial neural networks are useful for implementing non-linear process variables over time, and therefore are a useful tool for estimating the wind speed. The neural network used is multilayer perceptron with three layers and the supervised learning algorithm used is backpropagation. The inputs used in the neural network were wind speed and direction data from a single station, and the training patterns used correspond to sixty days data. The results obtained by simulating the annual average wind speed at the selected site based on data from nearby stations with correlation coefficients above 0.5 were satisfactory, compared with actual values. Reliable estimations were obtained, with errors below 6%

  8. SPEED COMPLIANCE IN FREEWAY VARIABLE SPEED LIMIT SYSTEM – CASE STUDY OF THE PRAGUE CITY RING

    Directory of Open Access Journals (Sweden)

    Michał MATOWICKI

    2016-03-01

    Full Text Available Many previous studies have confirmed the strong relationship between speed compliance and the frequency and severity of traffic accidents. Variable speed limit (VSL system as a measure to improve traffic safety enables the freeway system to change its posted speed limit based on various traffic and environmental conditions. Such system helps drivers to recognize the upcoming events, to adjust their driving style and in such way to address speed variation of the traffic flow. This is called speed harmonization. Although many studies researching the effect of VSL system on the traffic stream can be found, there are only few addressing its influence on the drivers behavior, particularly focusing on their tolerance limit and compliance, which has crucial meaning for future design of controlling algorithms. This study was prepared to inspect this grey area by studying the data from the VSL system at Prague city ring, describing the influence of the highway management system and its influence on drivers.

  9. Effect of rotation speed and welding speed on Friction Stir Welding of AA1100 Aluminium alloy

    Science.gov (United States)

    Raja, P.; Bojanampati, S.; Karthikeyan, R.; Ganithi, R.

    2018-04-01

    Aluminum AA1100 is the most widely used grade of Aluminium due to its excellent corrosion resistance, high ductility and reflective finish, the selected material was welded with Friction Stir Welding (FSW) process on a CNC machine, using a combination of different tool rotation speed (1500 rpm, 2500 rpm, 3500 rpm) and welding speed (10 mm/min, 30 mm/min, 50 mm/min) as welding parameters. The effect of FSW using this welding parameter was studied by measuring the ultimate tensile strength of the welded joints. A high-speed steel tool was prepared for welding the Aluminium AA1100 alloy having an 8mm shoulder diameter and pin dimension of 4mm diameter and 2.8 mm length. The welded joints were tested using the universal testing machine. It was found that Ultimate Tensile Strength of FSW specimen was highest with a value of 98.08 MPa when the weld was performed at rotation speed of 1500 RPM and welding speed of 50 mm/min.

  10. Science school and culture school: improving the efficiency of high school science teaching in a system of mass science education.

    Science.gov (United States)

    Charlton, Bruce G

    2006-01-01

    Educational expansion in western countries has been achieved mainly by adding years to full-time education; however, this process has probably reduced efficiency. Sooner or later, efficiency must improve, with a greater educational attainment per year. Future societies will probably wish more people to study science throughout high school (aged c. 11-19 years) and the first college degree. 'Science' may be defined as any abstract, systematic and research-based discipline: including mathematics, statistics and the natural sciences, economics, music theory, linguistics, and the conceptual or quantitative social sciences. Since formal teaching is usually necessary to learn science, science education should be regarded as the core function of high schools. One standard way to improve efficiency is the 'division of labour', with increased specialization of function. Modern schools are already specialized: teachers are specialized according to age-group taught, subject matter expertise, and administrative responsibilities. School students are stratified by age and academic aptitude. I propose a further institutional division of school function between science education, and cultural education (including education in arts, sports, ethics, social interaction and good citizenship). Existing schools might split into 'science school' and 'culture school', reflected in distinct buildings and zones, separate administrative structures, and the recruitment of differently-specialized teaching personnel. Science school would be distinguished by its focus on education in disciplines which promote abstract systematic cognition. All students would spend some part of each day (how much would depend on their aptitude and motivation) in the 'science school'; experiencing a traditional-style, didactic, disciplined and rigorous academic education. The remainder of the students' time at school would be spent in the cultural division, which would focus on broader aspects, and aim to generate

  11. Prediction of Ship Resonant Rolling - Related Dangerous Zones with Regard to the Equivalent Metacentric Height Governing Natural Frequency of Roll

    Directory of Open Access Journals (Sweden)

    Przemyslaw Krata

    2017-12-01

    Full Text Available Potentially dangerous zones corresponding to dynamical stability phenomena, possibly encountered by ships sailing in rough sea, are estimated nowadays with the use of the method recommended by IMO in the guidance coded MSC.1/Circ.1228. In this IMO method the parameter governing the natural period of roll is the initial metacentric height. Some earlier studies revealed that the initial metacentric height which is commonly in use on-board ships for the purpose of performing the MSC.1/Circ.1228-recommended calculations, may significantly vary from the so called equivalent metacentric height obtained for large amplitudes of ship’s roll. In the light of such ascertainment, the paper deals with resultant resonance roll zones locations with regard to the equivalent metacentric height concept remaining appropriate for large amplitudes of roll. The noteworthy transfer of the resonance zones location is disclosed which reflects the distinct configurations of potentially dangerous ship’s course and speed configurations than could be predicted on the basis the initial metacentric height.

  12. Assessing handwriting intervention effectiveness in elementary school students: a two-group controlled study.

    Science.gov (United States)

    Howe, Tsu-Hsin; Roston, Karen Laurie; Sheu, Ching-Fan; Hinojosa, Jim

    2013-01-01

    This study examined the effectiveness of two approaches used in elementary schools to improve children's handwriting. Participants were 72 New York City public school students from the first and second grades. A nonequivalent pretest-posttest group design was used in which students engaged in handwriting activities using two approaches: intensive handwriting practice and visual-perceptual-motor activities. Handwriting speed, legibility, and visual-motor skills were examined after a 12-wk Handwriting Club using multivariate analysis of variance. The results showed that students in the intensive handwriting practice group demonstrated significant improvements in handwriting legibility compared with students in the visual-perceptual-motor activity group. No significant effects in handwriting speed and visual-motor skills were found between the students in intensive handwriting practice group and the students in visual-perceptual-motor activities group. The Handwriting Club model is a natural intervention that fits easily into existing school curriculums and can be an effective short-term intervention (response to intervention Tier II). Copyright © 2013 by the American Occupational Therapy Association, Inc.

  13. 33 CFR 147.847 - Safety Zone; BW PIONEER Floating Production, Storage, and Offloading System Safety Zone.

    Science.gov (United States)

    2010-07-01

    ... Production, Storage, and Offloading System Safety Zone. 147.847 Section 147.847 Navigation and Navigable... ZONES § 147.847 Safety Zone; BW PIONEER Floating Production, Storage, and Offloading System Safety Zone. (a) Description. The BW PIONEER, a Floating Production, Storage and Offloading (FPSO) system, is in...

  14. Quantum speed limits for Bell-diagonal states

    International Nuclear Information System (INIS)

    Han Wei; Jiang Ke-Xia; Zhang Ying-Jie; Xia Yun-Jie

    2015-01-01

    The lower bounds of the evolution time between two distinguishable states of a system, defined as quantum speed limit time, can characterize the maximal speed of quantum computers and communication channels. We study the quantum speed limit time between the composite quantum states and their target states in the presence of nondissipative decoherence. For the initial states with maximally mixed marginals, we obtain the exact expressions of the quantum speed limit time which mainly depend on the parameters of the initial states and the decoherence channels. Furthermore, by calculating the quantum speed limit time for the time-dependent states started from a class of initial states, we discover that the quantum speed limit time gradually decreases in time, and the decay rate of the quantum speed limit time would show a sudden change at a certain critical time. Interestingly, at the same critical time, the composite system dynamics would exhibit a sudden transition from classical decoherence to quantum decoherence. (paper)

  15. Vibration characteristics of dental high-speed turbines and speed-increasing handpieces.

    Science.gov (United States)

    Poole, Ruth L; Lea, Simon C; Dyson, John E; Shortall, Adrian C C; Walmsley, A Damien

    2008-07-01

    Vibrations of dental handpieces may contribute to symptoms of hand-arm vibration syndrome in dental personnel and iatrogenic enamel cracking in teeth. However, methods for measuring dental handpiece vibrations have previously been limited and information about vibration characteristics is sparse. This preliminary study aimed to use a novel approach to assess the vibrations of unloaded high-speed handpieces in vitro. Maximum vibration displacement amplitudes of five air turbines and two speed-increasing handpieces were recorded whilst they were operated with and without a rotary cutting instrument (RCI) using a scanning laser vibrometer (SLV). RCI rotation speeds, calculated from frequency peaks, were consistent with expected values. ANOVA statistical analysis indicated significant differences in vibrations between handpiece models (p0.11). Operating handpieces with a RCI resulted in greater vibrations than with no RCI (pmeasurement exceeded 4 microm for the handpieces in the current test setup (implying that these vibrations may be unlikely to cause adverse effects), this study has formed the basis for future work which will include handpiece vibration measurements whilst cutting under clinically representative loads.

  16. Measure Guideline: Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, A.; Easley, S.

    2012-05-01

    The report evaluates potential energy savings by replacing traditional single-speed pool pumps with variable speed pool pumps, and provide a basic cost comparison between continued uses of traditional pumps verses new pumps. A simple step-by-step process for inspecting the pool area and installing a new pool pump follows.

  17. 78 FR 5717 - Safety Zone; Military Ocean Terminal Concord Safety Zone, Suisun Bay, Military Ocean Terminal...

    Science.gov (United States)

    2013-01-28

    ...-AA00 Safety Zone; Military Ocean Terminal Concord Safety Zone, Suisun Bay, Military Ocean Terminal... Guard is establishing a safety zone in the navigable waters of Suisun Bay near Military Ocean Terminal Concord, CA in support of military onload and offload operations. This safety zone is established to...

  18. Daytime pelagic schooling behaviour and relationships with plankton patch distribution in the Sicily Strait (Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    B. Patti

    2011-06-01

    Full Text Available In this study, hydroacoustic data collected with a scientific echosounder working at two frequencies (38 and 120 kHz over the continental shelf off the southern Sicilian coast were used in order to investigate the relationship between fish schools and plankton patches. Specifically, image analysis algorithms were applied to raw echograms in order to detect and characterise pelagic fish schools and plankton aggregations, considered as a proxy of food availability. The relationship was first investigated using estimated total plankton biomass over the whole water column and, second, by dividing the study area into three sub-regions and further distinguishing plankton patches between the surface and the bottom. In the relatively lower plankton abundance areas of Zone 1 (northern sector of the study area, results showed an inverse relationship between the biomass (and density of fish schools and the biomass of co-occurring plankton patches located close to the bottom. Instead, over the Sicilian-Maltese shelf (Zone 3, characterised by higher plankton abundances, a direct relationship was found when using plankton data from the whole water column. The observed difference between Zones 1 and 3 is probably due to diverse dominant fish species in the two sub-regions.

  19. Modeling pH-zone refining countercurrent chromatography: a dynamic approach.

    Science.gov (United States)

    Kotland, Alexis; Chollet, Sébastien; Autret, Jean-Marie; Diard, Catherine; Marchal, Luc; Renault, Jean-Hugues

    2015-04-24

    A model based on mass transfer resistances and acid-base equilibriums at the liquid-liquid interface was developed for the pH-zone refining mode when it is used in countercurrent chromatography (CCC). The binary separation of catharanthine and vindoline, two alkaloids used as starting material for the semi-synthesis of chemotherapy drugs, was chosen for the model validation. Toluene/CH3CN/water (4/1/5, v/v/v) was selected as biphasic solvent system. First, hydrodynamics and mass transfer were studied by using chemical tracers. Trypan blue only present in the aqueous phase allowed the determination of the parameters τextra and Pe for hydrodynamic characterization whereas acetone, which partitioned between the two phases, allowed the determination of the transfer parameter k0a. It was shown that mass transfer was improved by increasing both flow rate and rotational speed, which is consistent with the observed mobile phase dispersion. Then, the different transfer parameters of the model (i.e. the local transfer coefficient for the different species involved in the process) were determined by fitting experimental concentration profiles. The model accurately predicted both equilibrium and dynamics factors (i.e. local mass transfer coefficients and acid-base equilibrium constant) variation with the CCC operating conditions (cell number, flow rate, rotational speed and thus stationary phase retention). The initial hypotheses (the acid-base reactions occurs instantaneously at the interface and the process is mainly governed by mass transfer) are thus validated. Finally, the model was used as a tool for catharanthine and vindoline separation prediction in the whole experimental domain that corresponded to a flow rate between 20 and 60 mL/min and rotational speeds from 900 and 2100 rotation per minutes. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Investigating Car Users’ Driving Behaviour through Speed Analysis

    Directory of Open Access Journals (Sweden)

    Laura Eboli

    2017-04-01

    Full Text Available Speed has been identified for a long time as a key risk factor in road traffic: inappropriate speeds contribute to a relevant part of traffic accidents. Many literature studies have focused on the relationship between speed and accident risk. Starting from this consideration this paper investigates traffic accident risk by analysing the travelling speeds recorded by real tests on the road. A survey was conducted to collect experimental speed values in a real context. A specific road segment, belonging to an Italian rural two-lane road, was repeatedly run by 27 drivers in order to collect the instantaneous speed values for each trajectory. Smartphone-equipped vehicles were used to record continuous speed data. The recorded data were used to calculate: the average speed, 50th and 85th percentile speed for each geometric element of the analysed road segment. The main result of the research is the classification of car users’ driving behaviour based on the speed values. By using the above mentioned ranges of speed, the classification provides three types of driving behaviour: safe, unsafe, and safe but potentially dangerous. It was found that only four drivers feature “safe” behaviour, driving in a safe manner on most of the road elements. However, the major part of drivers, even if they feature safe behaviour, could be dangerous for other drivers because they drive at very low speeds.

  1. High-speed cinematography of gas-metal atomization

    Energy Technology Data Exchange (ETDEWEB)

    Ting, Jason [ALCOA Specialty Metals Division, 100 Technical Drive, Alcoa Center, PA 15069 (United States)]. E-mail: jason.ting@alcoa.com; Connor, Jeffery [Material Science Engineering Department, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Ridder, Stephen [Metallurgical Processing Group, NIST, 100 Bureau Dr. Stop 8556, Gaithersburg, MD 20899 (United States)

    2005-01-15

    A high-speed cinematographic footage of a 304L stainless steel gas atomization, recorded at the National Institute of Standard and Technology (NIST), was analyzed using a discrete Fourier transform (DFT) algorithm. The analysis showed the gas atomization process possesses two prominent frequency ranges of melt oscillation (pulsation). A low-frequency oscillation in the melt flow occurring between 5.41 and 123 Hz, with a dominant frequency at 9.93 Hz, was seen in the recirculation zone adjacent to the melt orifice. A high-frequency melt oscillation range was observed above 123 Hz, and was more prominent one melt-tip-diameter downstream in the melt atomization image than upstream near the melt tip. This high-frequency range may reflect the melt atomization frequency used to produce finely atomized powder. This range also included a prominent high frequency at 1273 Hz, which dominated in the image further away downstream from the melt tip. This discrete high-frequency oscillation is most probably caused by the aeroacoustic ''screech'' phenomenon, intrasound (<20 kHz), a result of the atomizing gas jets undergoing flow resonance. It is hypothesized that this discrete intrinsic aeroacoustic tone may enhance melt breakup in the atomization process with evidence of this fact in the melt images.

  2. High-speed cinematography of gas-metal atomization

    International Nuclear Information System (INIS)

    Ting, Jason; Connor, Jeffery; Ridder, Stephen

    2005-01-01

    A high-speed cinematographic footage of a 304L stainless steel gas atomization, recorded at the National Institute of Standard and Technology (NIST), was analyzed using a discrete Fourier transform (DFT) algorithm. The analysis showed the gas atomization process possesses two prominent frequency ranges of melt oscillation (pulsation). A low-frequency oscillation in the melt flow occurring between 5.41 and 123 Hz, with a dominant frequency at 9.93 Hz, was seen in the recirculation zone adjacent to the melt orifice. A high-frequency melt oscillation range was observed above 123 Hz, and was more prominent one melt-tip-diameter downstream in the melt atomization image than upstream near the melt tip. This high-frequency range may reflect the melt atomization frequency used to produce finely atomized powder. This range also included a prominent high frequency at 1273 Hz, which dominated in the image further away downstream from the melt tip. This discrete high-frequency oscillation is most probably caused by the aeroacoustic ''screech'' phenomenon, intrasound (<20 kHz), a result of the atomizing gas jets undergoing flow resonance. It is hypothesized that this discrete intrinsic aeroacoustic tone may enhance melt breakup in the atomization process with evidence of this fact in the melt images

  3. Increased Surface Wind Speeds Follow Diminishing Arctic Sea Ice

    Science.gov (United States)

    Mioduszewski, J.; Vavrus, S. J.; Wang, M.; Holland, M. M.; Landrum, L.

    2017-12-01

    Projections of Arctic sea ice through the end of the 21st century indicate the likelihood of a strong reduction in ice area and thickness in all seasons, leading to a substantial thermodynamic influence on the overlying atmosphere. This is likely to have an effect on winds over the Arctic Basin, due to changes in atmospheric stability and/or baroclinicity. Prior research on future Arctic wind changes is limited and has focused mainly on the practical impacts on wave heights in certain seasons. Here we attempt to identify patterns and likely mechanisms responsible for surface wind changes in all seasons across the Arctic, particularly those associated with sea ice loss in the marginal ice zone. Sea level pressure, near-surface (10 m) and upper-air (850 hPa) wind speeds, and lower-level dynamic and thermodynamic variables from the Community Earth System Model Large Ensemble Project (CESM-LE) were analyzed for the periods 1971-2000 and 2071-2100 to facilitate comparison between a present-day and future climate. Mean near-surface wind speeds over the Arctic Ocean are projected to increase by late century in all seasons but especially during autumn and winter, when they strengthen by up to 50% locally. The most extreme wind speeds in the 90th percentile change even more, increasing in frequency by over 100%. The strengthened winds are closely linked to decreasing lower-tropospheric stability resulting from the loss of sea ice cover and consequent surface warming (locally over 20 ºC warmer in autumn and winter). A muted pattern of these future changes is simulated in CESM-LE historical runs from 1920-2005. The enhanced winds near the surface are mostly collocated with weaker winds above the boundary layer during autumn and winter, implying more vigorous vertical mixing and a drawdown of high-momentum air.The implications of stronger future winds include increased coastal hazards and the potential for a positive feedback with sea ice by generating higher winds and

  4. The radial speed-expansion speed relation for Earth-directed CMEs

    Science.gov (United States)

    Mäkelä, P.; Gopalswamy, N.; Yashiro, S.

    2016-05-01

    Earth-directed coronal mass ejections (CMEs) are the main drivers of major geomagnetic storms. Therefore, a good estimate of the disturbance arrival time at Earth is required for space weather predictions. The STEREO and SOHO spacecraft were viewing the Sun in near quadrature during January 2010 to September 2012, providing a unique opportunity to study the radial speed (Vrad)-expansion speed (Vexp) relationship of Earth-directed CMEs. This relationship is useful in estimating the Vrad of Earth-directed CMEs, when they are observed from Earth view only. We selected 19 Earth-directed CMEs observed by the Large Angle and Spectrometric Coronagraph (LASCO)/C3 coronagraph on SOHO and the Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI)/COR2 coronagraph on STEREO during January 2010 to September 2012. We found that of the three tested geometric CME models the full ice-cream cone model of the CME describes best the Vrad-Vexp relationship, as suggested by earlier investigations. We also tested the prediction accuracy of the empirical shock arrival (ESA) model proposed by Gopalswamy et al. (2005a), while estimating the CME propagation speeds from the CME expansion speeds. If we use STEREO observations to estimate the CME width required to calculate the Vrad from the Vexp measurements, the mean absolute error (MAE) of the shock arrival times of the ESA model is 8.4 h. If the LASCO measurements are used to estimate the CME width, the MAE still remains below 17 h. Therefore, by using the simple Vrad-Vexp relationship to estimate the Vrad of the Earth-directed CMEs, the ESA model is able to predict the shock arrival times with accuracy comparable to most other more complex models.

  5. Variable current speed controller for eddy current motors

    Science.gov (United States)

    Gerth, H.L.; Bailey, J.M.; Casstevens, J.M.; Dixon, J.H.; Griffith, B.O.; Igou, R.E.

    1982-03-12

    A speed control system for eddy current motors is provided in which the current to the motor from a constant frequency power source is varied by comparing the actual motor speed signal with a setpoint speed signal to control the motor speed according to the selected setpoint speed. A three-phase variable voltage autotransformer is provided for controlling the voltage from a three-phase power supply. A corresponding plurality of current control resistors is provided in series with each phase of the autotransformer output connected to inputs of a three-phase motor. Each resistor is connected in parallel with a set of normally closed contacts of plurality of relays which are operated by control logic. A logic circuit compares the selected speed with the actual motor speed obtained from a digital tachometer monitoring the motor spindle speed and operated the relays to add or substract resistance equally in each phase of the motor input to vary the motor current to control the motor at the selected speed.

  6. Climate variability and environmental stress in the Sudan-Sahel zone of West Africa.

    Science.gov (United States)

    Mertz, Ole; D'haen, Sarah; Maiga, Abdou; Moussa, Ibrahim Bouzou; Barbier, Bruno; Diouf, Awa; Diallo, Drissa; Da, Evariste Dapola; Dabi, Daniel

    2012-06-01

    Environmental change in the Sudan-Sahel region of West Africa (SSWA) has been much debated since the droughts of the 1970s. In this article we assess climate variability and environmental stress in the region. Households in Senegal, Mali, Burkina Faso, Niger, and Nigeria were asked about climatic changes and their perceptions were compared across north-south and west-east rainfall gradients. More than 80% of all households found that rainfall had decreased, especially in the wettest areas. Increases in wind speeds and temperature were perceived by an overall 60-80% of households. Contrary to household perceptions, observed rainfall patterns showed an increasing trend over the past 20 years. However, August rainfall declined, and could therefore potentially explain the contrasting negative household perceptions of rainfall trends. Most households reported degradation of soils, water resources, vegetation, and fauna, but more so in the 500-900 mm zones. Adaptation measures to counter environmental degradation included use of manure, reforestation, soil and water conservation, and protection of fauna and vegetation. The results raise concerns for future environmental management in the region, especially in the 500-900 mm zones and the western part of SSWA.

  7. Measure Guideline. Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, A. [Building Media and the Building America Retrofit Alliance (BARA), Wilmington, DE (United States); Easley, S. [Building Media and the Building America Retrofit Alliance (BARA), Wilmington, DE (United States)

    2012-05-01

    This measure guideline evaluates potential energy savings by replacing traditional single-speed pool pumps with variable speed pool pumps, and provides a basic cost comparison between continued uses of traditional pumps verses new pumps. A simple step-by-step process for inspecting the pool area and installing a new pool pump follows.

  8. Influence of “J”-Curve Spring Stiffness on Running Speeds of Segmented Legs during High-Speed Locomotion

    Directory of Open Access Journals (Sweden)

    Runxiao Wang

    2016-01-01

    Full Text Available Both the linear leg spring model and the two-segment leg model with constant spring stiffness have been broadly used as template models to investigate bouncing gaits for legged robots with compliant legs. In addition to these two models, the other stiffness leg spring models developed using inspiration from biological characteristic have the potential to improve high-speed running capacity of spring-legged robots. In this paper, we investigate the effects of “J”-curve spring stiffness inspired by biological materials on running speeds of segmented legs during high-speed locomotion. Mathematical formulation of the relationship between the virtual leg force and the virtual leg compression is established. When the SLIP model and the two-segment leg model with constant spring stiffness and with “J”-curve spring stiffness have the same dimensionless reference stiffness, the two-segment leg model with “J”-curve spring stiffness reveals that (1 both the largest tolerated range of running speeds and the tolerated maximum running speed are found and (2 at fast running speed from 25 to 40/92 m s−1 both the tolerated range of landing angle and the stability region are the largest. It is suggested that the two-segment leg model with “J”-curve spring stiffness is more advantageous for high-speed running compared with the SLIP model and with constant spring stiffness.

  9. 78 FR 24679 - Safety Zones; Fireworks Displays in Captain of the Port Long Island Sound Zone

    Science.gov (United States)

    2013-04-26

    ...-AA00 Safety Zones; Fireworks Displays in Captain of the Port Long Island Sound Zone AGENCY: Coast Guard... zones for fireworks displays within the Captain of the Port (COTP) Long Island Sound (LIS) Zone. This... Sector Long Island Sound. DATES: This rule is effective from April 27, 2013, until June 22, 2013. This...

  10. 76 FR 34867 - Safety Zones; Annual Fireworks Events in the Captain of the Port Detroit Zone

    Science.gov (United States)

    2011-06-15

    ....941(a)(51) Target Fireworks, Detroit, MI The first safety zone will be enforced from 7 a.m. on June 24... Zones; Annual Fireworks Events in the Captain of the Port Detroit Zone AGENCY: Coast Guard, DHS. ACTION: Notice of enforcement of regulation. SUMMARY: The Coast Guard will enforce various safety zones for...

  11. Family Smoking Prevention And Tobacco Control Act: banning outdoor tobacco advertising near schools and playgrounds.

    Science.gov (United States)

    Luke, Douglas A; Ribisl, Kurt M; Smith, Carson; Sorg, Amy A

    2011-03-01

    The tobacco industry has challenged new FDA rules restricting outdoor tobacco advertising near schools and playgrounds on First Amendment grounds, arguing that they would lead to a near complete ban on tobacco advertising in dense urban areas. To examine how the 2009 Family Smoking Prevention and Tobacco Control Act (FSPTCA) rules banning outdoor tobacco advertising near schools and playgrounds would affect tobacco retailers. GIS spatial analyses of two different states (Missouri, New York), along with more detailed analyses of two urban areas within those states (St. Louis, New York City), were conducted in 2010. The percentage of tobacco retailers falling within 350-, 500-, and 1000-foot buffer zones was then calculated. 22% of retailers in Missouri and 51% in New York fall within 1000-foot buffers around schools. In urban settings, more retailers are affected, 29% in St. Louis and 79% in New York City. Sensitivity analyses demonstrate that smaller buffers decrease the proportion of affected retailers. That is, 350-foot buffers affect only 6.7% of retailers in St. Louis and 29% in New York City. The effects of new outdoor tobacco advertising restrictions vary by location and population density. In Missouri and New York, outdoor tobacco advertising would still be permitted in many locations if such advertising was prohibited in a 1000-foot buffer zone around schools and playgrounds. Much smaller buffer zones of 350 feet may result in almost no reduction of outdoor advertising in many parts of the country. Copyright © 2011. Published by Elsevier Inc.

  12. Theoretical analysis of recirculation zone and buffer zone in the ADS windowless spallation target

    International Nuclear Information System (INIS)

    Liu, Jie; Pan, Chang-zhao; Tong, Jian-fei; Lu, Wen-qiang

    2015-01-01

    Highlights: • Height of recirculation zone is very important in windowless target design. • A theoretical formula for the height is derived based on the Bernoulli equation. • Numerical simulation for the LBE is performed and the height of recirculation zone is also obtained. • The theoretically-derived simulation-predicted recirculation zone heights agree with each other very well and the theoretical derivation is proved to be correct. - Abstract: The thermo-hydraulic analysis including reduction of the height of recirculation zone and stability of the free surface is very important in the design and optimization of ADS windowless spallation targets. In the present study, the Bernoulli equation is used to analyze the entire flow process in the target. Formulae for the height of the recirculation zone and the buffer zone are both obtained explicitly. Furthermore, numerical simulation for the heavy metal lead–bismuth eutectic liquid and vapor with cavitation phase change is also performed, and a novel method to calculate the height of the recirculation zone is put forward. By comparison of the theoretical formulae and numerical results, it is clearly shown that they agree with each other very well, and the heights predicted by the two methods are both determined by their own upstream flow parameters

  13. 76 FR 42048 - Safety Zones; Swimming Events in Captain of the Port Boston Zone

    Science.gov (United States)

    2011-07-18

    ...-AA00 Safety Zones; Swimming Events in Captain of the Port Boston Zone AGENCY: Coast Guard, DHS. ACTION... events within the Captain of the Port (COTP) Boston Zone for swimming events. This action is necessary to... property on navigable waters from the hazardous nature of swimming events such as large numbers of swimmers...

  14. Schools and communities in Hungary

    Science.gov (United States)

    Hunyady, Susan

    1980-09-01

    The democratic reform of public education in Hungary after the Second World War brought about a system which now includes Day-Care from the ages of 4-6 and compulsory Elementary School education up to the age of 16. A high proportion of students go on to Secondary education in vocational schools, special schools or grammar shools. The system is supplemented by career-counselling and provision for children with difficult home-backgrounds and for the mentally-retarded. District Councils are responsible for the schools in their areas and for the zoning that determines which schools children should attend. The environment of a school has a strong influence not only upon the standard of its facilities and the quality of its staff but also upon the function it is expected to fulfil in the community. Achievement is directly related to the degree of urbanization, but the increasing participation of farming-co-operatives in education in rural areas promises well for the development of better facilities and mutual understanding there. Housing estates in high-density residential areas make special demands which are being met in different ways. The role of the school in general is being expanded to include children's leisure time activities; at the same time factories are making a significant contribution locally through vocational guidance, financial help, and training-for-work programmes. Councils are implementing the requirements of public education resolutions to integrate school education into the whole scheme of public education, co-ordinating the activities of all social and cultural institutions, and developing new multi-functional complexes, to give a more effective and efficient service to the whole community.

  15. Habitable Zones in the Universe

    OpenAIRE

    Gonzalez, G.

    2005-01-01

    Habitability varies dramatically with location and time in the universe. This was recognized centuries ago, but it was only in the last few decades that astronomers began to systematize the study of habitability. The introduction of the concept of the habitable zone was key to progress in this area. The habitable zone concept was first applied to the space around a star, now called the Circumstellar Habitable Zone. Recently, other, vastly broader, habitable zones have been proposed. We review...

  16. Toward Greater Understanding of the Relationship between Public Perceptions of Speed, Speed Laws, and Safety

    Science.gov (United States)

    2018-02-01

    Speed continues to be a leading factor contributing to traffic fatalities in the U.S., implicated in over 9,500 deaths in 2015. Despite this, in recent years, some states have moved toward more lenient speed enforcement regimes. A public choice probl...

  17. Driving simulator validation of driver behavior with limited safe vantage points for data collection in work zones.

    Science.gov (United States)

    Bham, Ghulam H; Leu, Ming C; Vallati, Manoj; Mathur, Durga R

    2014-06-01

    This study is aimed at validating a driving simulator (DS) for the study of driver behavior in work zones. A validation study requires field data collection. For studies conducted in highway work zones, the availability of safe vantage points for data collection at critical locations can be a significant challenge. A validation framework is therefore proposed in this paper, demonstrated using a fixed-based DS that addresses the issue by using a global positioning system (GPS). The validation of the DS was conducted using objective and subjective evaluations. The objective validation was divided into qualitative and quantitative evaluations. The DS was validated by comparing the results of simulation with the field data, which were collected using a GPS along the highway and video recordings at specific locations in a work zone. The constructed work zone scenario in the DS was subjectively evaluated with 46 participants. The objective evaluation established the absolute and relative validity of the DS. The mean speeds from the DS data showed excellent agreement with the field data. The subjective evaluation indicated realistic driving experience by the participants. The use of GPS showed that continuous data collected along the highway can overcome the challenges of unavailability of safe vantage points especially at critical locations. Further, a validated DS can be used for examining driver behavior in complex situations by replicating realistic scenarios. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Radiation protection principles observance in Iranian dental schools

    International Nuclear Information System (INIS)

    Eskandarlou, A.; Ghazi-khanlou Sani, K.; Mehdizadeh, A. R.

    2010-01-01

    In recent decades many guidelines has been conducted by radiation protection organizations about radiation protection in dentistry. This study aimed to evaluate the observance of these guidelines in educational clinics of all dental schools in Iran. Material and Methods: In this cross-sectional study a self-administered questionnaire, based on National Radiation Protection Board and European Commission guidelines, was conducted. The radiology departments of all dental school (18 schools) were surveyed in this study. The questionnaire was consisted of 3 sections including intraoral radiography, extra oral radiography and implementation of quality control programs. Results: In the case of the existence of radiation protection facilities (such as lead apron, thyroid shield and lead impacted walls) the use of high speed films and existence of automatic processor in dental schools, there was a proper condition. The main problem was related to lack of regular quality control and quality assurance programs. Digital radiography systems were employed in none of the schools and it was occasionally used for research purposes at some of them. Conclusions: This study has emphasized on the need for further consideration of radiation protection principles in dental schools, especially on the field of quality control and quality assurance programs.

  19. Fixed-speed and Variable-speed Pumped Storage Dispatch Model in Power Systems with High Renewable Penetration

    Science.gov (United States)

    Yuan, Bo; Zong, Jin; Xu, Zhicheng

    2018-06-01

    According to different operating characteristics of pumped storage fixed speed unit and variable speed unit, a joint dispatching model of pumped storage unit and other types of units based on mixed integer linear optimization is constructed. The model takes into account the operating conditions, reservoir capacity, cycle type and other pumped storage unit constraints, but also consider the frequent start and stop and the stability of the operation of the unit caused by the loss. Using the Cplex solver to solve the model, the empirical example of the provincial power grid shows that the model can effectively arrange the pumping storage speed and the dispatching operation of the variable speed unit under the precondition of economic life of the unit, and give full play to the function of peak shaving and accommodating new energy. Because of its more flexible regulation characteristics of power generation and pumping conditions, the variable speed unit can better improve the operating conditions of other units in the system and promote the new energy dissipation.

  20. Fixed-speed and Variable-speed Pumped Storage Dispatch Model in Power Systems with High Renewable Penetration

    Directory of Open Access Journals (Sweden)

    Yuan Bo

    2018-01-01

    Full Text Available According to different operating characteristics of pumped storage fixed speed unit and variable speed unit, a joint dispatching model of pumped storage unit and other types of units based on mixed integer linear optimization is constructed. The model takes into account the operating conditions, reservoir capacity, cycle type and other pumped storage unit constraints, but also consider the frequent start and stop and the stability of the operation of the unit caused by the loss. Using the Cplex solver to solve the model, the empirical example of the provincial power grid shows that the model can effectively arrange the pumping storage speed and the dispatching operation of the variable speed unit under the precondition of economic life of the unit, and give full play to the function of peak shaving and accommodating new energy. Because of its more flexible regulation characteristics of power generation and pumping conditions, the variable speed unit can better improve the operating conditions of other units in the system and promote the new energy dissipation.

  1. White Matter Fractional Anisotropy Correlates With Speed of Processing and Motor Speed in Young Childhood Cancer Survivors

    International Nuclear Information System (INIS)

    Aukema, Eline J.; Caan, Matthan W.A.; Oudhuis, Nienke; Majoie, Charles; Vos, Frans M.; Reneman, Liesbeth; Last, Bob F.; Grootenhuis, Martha A.; Schouten-van Meeteren, Antoinette Y.N.

    2009-01-01

    Purpose: To determine whether childhood medulloblastoma and acute lymphoblastic leukemia (ALL) survivors have decreased white matter fractional anisotropy (WMFA) and whether WMFA is related to the speed of processing and motor speed. Methods and Materials: For this study, 17 patients (6 medulloblastoma, 5 ALL treated with high-dose methotrexate (MTX) (4 x 5 g/m 2 ) and 6 with low-dose MTX (3 x 2 g/m 2 )) and 17 age-matched controls participated. On a 3.0-T magnetic resonance imaging (MRI) scanner, diffusion tensor imaging (DTI) was performed, and WMFA values were calculated, including specific regions of interest (ROIs), and correlated with the speed of processing and motor speed. Results: Mean WMFA in the patient group, mean age 14 years (range 8.9 - 16.9), was decreased compared with the control group (p = 0.01), as well as WMFA in the right inferior fronto-occipital fasciliculus (IFO) (p = 0.03) and in the genu of the corpus callosum (gCC) (p = 0.01). Based on neurocognitive results, significant positive correlations were present between processing speed and WMFA in the splenium (sCC) (r = 0.53, p = 0.03) and the body of the corpus callosum (bCC) (r = 0.52, p = 0.03), whereas the right IFO WMFA was related to motor speed (r = 0.49, p < 0.05). Conclusions: White matter tracts, using a 3.0-T MRI scanner, show impairment in childhood cancer survivors, medulloblastoma survivors, and also those treated with high doses of MTX. In particular, white matter tracts in the sCC, bCC and right IFO are positively correlated with speed of processing and motor speed.

  2. Towards a Comparative and International History of School Testing and Accountability

    Science.gov (United States)

    Dorn, Sherman; Ydesen, Christian

    2014-01-01

    The speed and extent of modern school accountability have obscured the history of testing and accountability. This brief introduction identifies central themes of historical research into educational accountability and recurring traits associated with accountability practices. We hope our colleagues and this special issue will also help to…

  3. Variable-speed, portable routing skate

    Science.gov (United States)

    Pesch, W. A.

    1967-01-01

    Lightweight, portable, variable-speed routing skate is used on heavy metal subassemblies which are impractical to move to a stationary machine. The assembly, consisting of the housing with rollers, router, and driving mechanism with transmission, weighs about forty pounds. Both speed and depth of cut are adjustable.

  4. System analysis of automated speed enforcement implementation.

    Science.gov (United States)

    2016-04-01

    Speeding is a major factor in a large proportion of traffic crashes, injuries, and fatalities in the United States. Automated Speed Enforcement (ASE) is one of many approaches shown to be effective in reducing speeding violations and crashes. However...

  5. Optimal stride frequencies in running at different speeds.

    Directory of Open Access Journals (Sweden)

    Ben T van Oeveren

    Full Text Available During running at a constant speed, the optimal stride frequency (SF can be derived from the u-shaped relationship between SF and heart rate (HR. Changing SF towards the optimum of this relationship is beneficial for energy expenditure and may positively change biomechanics of running. In the current study, the effects of speed on the optimal SF and the nature of the u-shaped relation were empirically tested using Generalized Estimating Equations. To this end, HR was recorded from twelve healthy (4 males, 8 females inexperienced runners, who completed runs at three speeds. The three speeds were 90%, 100% and 110% of self-selected speed. A self-selected SF (SFself was determined for each of the speeds prior to the speed series. The speed series started with a free-chosen SF condition, followed by five imposed SF conditions (SFself, 70, 80, 90, 100 strides·min-1 assigned in random order. The conditions lasted 3 minutes with 2.5 minutes of walking in between. SFself increased significantly (p<0.05 with speed with averages of 77, 79, 80 strides·min-1 at 2.4, 2.6, 2.9 m·s-1, respectively. As expected, the relation between SF and HR could be described by a parabolic curve for all speeds. Speed did not significantly affect the curvature, nor did it affect optimal SF. We conclude that over the speed range tested, inexperienced runners may not need to adapt their SF to running speed. However, since SFself were lower than the SFopt of 83 strides·min-1, the runners could reduce HR by increasing their SFself.

  6. Visual Processing Speeds in Children

    Directory of Open Access Journals (Sweden)

    Steve Croker

    2011-01-01

    Full Text Available The aim of this study was to investigate visual processing speeds in children. A rapid serial visual presentation (RSVP task with schematic faces as stimuli was given to ninety-nine 6–10-year-old children as well as a short form of the WISC-III. Participants were asked to determine whether a happy face stimulus was embedded in a stream of distracter stimuli. Presentation time was gradually reduced from 500 ms per stimulus to 100 ms per stimulus, in 50 ms steps. The data revealed that (i RSVP speed increases with age, (ii children aged 8 years and over can discriminate stimuli presented every 100 ms—the speed typically used with RSVP procedures in adult and adolescent populations, and (iii RSVP speed is significantly correlated with digit span and object assembly. In consequence, the RSVP paradigm presented here is appropriate for use in further investigations of processes of temporal attention within this cohort.

  7. "Defining Computer 'Speed': An Unsolved Challenge"

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    Abstract: The reason we use computers is their speed, and the reason we use parallel computers is that they're faster than single-processor computers. Yet, after 70 years of electronic digital computing, we still do not have a solid definition of what computer 'speed' means, or even what it means to be 'faster'. Unlike measures in physics, where the definition of speed is rigorous and unequivocal, in computing there is no definition of speed that is universally accepted. As a result, computer customers have made purchases misguided by dubious information, computer designers have optimized their designs for the wrong goals, and computer programmers have chosen methods that optimize the wrong things. This talk describes why some of the obvious and historical ways of defining 'speed' haven't served us well, and the things we've learned in the struggle to find a definition that works. Biography: Dr. John Gustafson is a Director ...

  8. Enhancing Personal Hygiene Behavior and Competency of Elementary School Adolescents through Peer-Led Approach and School-Friendly: A Quasi-Experimental Study.

    Science.gov (United States)

    Tamiru, Dessalegn; Argaw, Alemayehu; Gerbaba, Mulusew; Ayana, Girmay; Nigussie, Aderajew; Jisha, Hunduma; Belachew, Tefera

    2017-05-01

    Recent studies showed that poor personal hygiene practices play a major role in the increment of communicable disease burden in developing countries. In Ethiopia, 60% of the disease burden is related to poor sanitation practices. This school based study was aimed to assess the effectiveness of school-friendly and peer-led approach in improving personal hygiene practices of school adolescents in Jimma Zone, Southwest of Ethiopia. A total of 1000 students from 10 to 19 years were included into the study. The intervention was done using peer-led approach, health clubs and linking the school events with parents. Data were collected at baseline, midline and end-line using structured questionnaires. Repeated measurement analysis was done and statistical significance was considered at alpha 0.05. The findings of this study indicated that there was a significant difference in personal hygiene practices and knowledge between the intervention and control groups (Ppersonal hygiene knowledge and practice of students in the intervention schools. Therefore, there is a need for proper health education intervention through the framework of schools for the students to improve their personal hygiene knowledge and practices.

  9. Mechanical properties of fracture zones

    International Nuclear Information System (INIS)

    Leijon, B.

    1993-05-01

    Available data on mechanical characteristics of fracture zones are compiled and discussed. The aim is to improve the basis for adequate representation of fracture zones in geomechanical models. The sources of data researched are primarily borehole investigations and case studies in rock engineering, involving observations of fracture zones subjected to artificial load change. Boreholes only yield local information about the components of fracture zones, i.e. intact rock, fractures and various low-strength materials. Difficulties are therefore encountered in evaluating morphological and mechanical properties of fracture zones from borehole data. Although often thought of as macroscopically planar features, available field data consistently show that fracture zones are characterized by geometrical irregularities such as thickness variations, surface undulation and jogs. These irregularities prevail on all scales. As a result, fracture zones are on all scales characterized by large, in-plane variation of strength- and deformational properties. This has important mechanical consequences in terms of non-uniform stress transfer and complex mechanisms of shear deformation. Field evidence for these findings, in particular results from the underground research laboratory in Canada and from studies of induced fault slip in deep mines, is summarized and discussed. 79 refs

  10. Assessments of wind-energy potential in selected sites from three geopolitical zones in Nigeria: implications for renewable/sustainable rural electrification.

    Science.gov (United States)

    Okeniyi, Joshua Olusegun; Ohunakin, Olayinka Soledayo; Okeniyi, Elizabeth Toyin

    2015-01-01

    Electricity generation in rural communities is an acute problem militating against socioeconomic well-being of the populace in these communities in developing countries, including Nigeria. In this paper, assessments of wind-energy potential in selected sites from three major geopolitical zones of Nigeria were investigated. For this, daily wind-speed data from Katsina in northern, Warri in southwestern and Calabar in southeastern Nigeria were analysed using the Gumbel and the Weibull probability distributions for assessing wind-energy potential as a renewable/sustainable solution for the country's rural-electrification problems. Results showed that the wind-speed models identified Katsina with higher wind-speed class than both Warri and Calabar that were otherwise identified as low wind-speed sites. However, econometrics of electricity power simulation at different hub heights of low wind-speed turbine systems showed that the cost of electric-power generation in the three study sites was converging to affordable cost per kWh of electric energy from the wind resource at each site. These power simulations identified cost/kWh of electricity generation at Kaduna as €0.0507, at Warri as €0.0774, and at Calabar as €0.0819. These bare positive implications on renewable/sustainable rural electrification in the study sites even as requisite options for promoting utilization of this viable wind-resource energy in the remote communities in the environs of the study sites were suggested.

  11. Assessments of Wind-Energy Potential in Selected Sites from Three Geopolitical Zones in Nigeria: Implications for Renewable/Sustainable Rural Electrification

    Science.gov (United States)

    Okeniyi, Joshua Olusegun; Ohunakin, Olayinka Soledayo; Okeniyi, Elizabeth Toyin

    2015-01-01

    Electricity generation in rural communities is an acute problem militating against socioeconomic well-being of the populace in these communities in developing countries, including Nigeria. In this paper, assessments of wind-energy potential in selected sites from three major geopolitical zones of Nigeria were investigated. For this, daily wind-speed data from Katsina in northern, Warri in southwestern and Calabar in southeastern Nigeria were analysed using the Gumbel and the Weibull probability distributions for assessing wind-energy potential as a renewable/sustainable solution for the country's rural-electrification problems. Results showed that the wind-speed models identified Katsina with higher wind-speed class than both Warri and Calabar that were otherwise identified as low wind-speed sites. However, econometrics of electricity power simulation at different hub heights of low wind-speed turbine systems showed that the cost of electric-power generation in the three study sites was converging to affordable cost per kWh of electric energy from the wind resource at each site. These power simulations identified cost/kWh of electricity generation at Kaduna as €0.0507, at Warri as €0.0774, and at Calabar as €0.0819. These bare positive implications on renewable/sustainable rural electrification in the study sites even as requisite options for promoting utilization of this viable wind-resource energy in the remote communities in the environs of the study sites were suggested. PMID:25879063

  12. Speed checks on the CERN site

    CERN Multimedia

    2007-01-01

    In view of the significant number of speeding incidents that have been reported, CERN will shortly start to carry out speed checks on the site. The radar used for this purpose will show drivers the speed measured. The disciplinary measures taken against those exceeding the authorised limit (generally 50 k.p.h.) will include a ban from driving on the site for a minimum of one month. Maximilian Metzger
Secretary-General

  13. The variation in visibility and its relationship with surface wind speed in China from 1960 to 2009

    Science.gov (United States)

    Sun, Tianze; Che, Huizheng; Wu, Jian; Wang, Hong; Wang, Yaqiang; Zhang, Xiaoye

    2018-01-01

    This study used daily visibility and surface wind speed observational data over the 50-year period from 1960 to 2009, from 464 national meteorological stations in China, to examine the relationship between these two variables. Specifically, using the statistical methods of empirical orthogonal function (EOF) analysis and wavelet analysis, the data were processed into anomaly data to study their spatial and temporal distributions and the characteristics of each pattern's periodicity after EOF analysis of the whole country's visibility and surface wind speed. Correlation analysis and composite analysis were then used to elucidate the relationship between the two variables on different time scales. The results showed a gradual reduction in visibility nationally, with the nine-point moving mean implying decadal variability of the visibility with a downward trend. However, an irregular oscillation was found for the inter-annual variability of visibility. For the anomaly series of visibility during the 50-year period, a long-period oscillation of around 32 years was apparent. Up until the 1990s, there was an approximate 16-year medium-term oscillation period, whereas, after the 1990s, an approximate 8-year oscillation period was generated. In terms of high correlation between the two variables, for the decadal variability, the changes in visibility and surface wind speed at this time scale were almost in agreement. Meanwhile, with respect to the serious pollution in the Yangtze River Delta Economic Zone, the correlation between the two variables was reasonably high, suggesting that surface wind had a significant influence on the scattering of aerosol particles. However, in the Sichuan Basin, the correlation was relatively low, possibly on account of its landscape limiting the variation of wind speed.

  14. Peer influence predicts speeding prevalence among teenage drivers.

    Science.gov (United States)

    Simons-Morton, Bruce G; Ouimet, Marie Claude; Chen, Rusan; Klauer, Sheila G; Lee, Suzanne E; Wang, Jing; Dingus, Thomas A

    2012-12-01

    Preventing speed-related crashes could reduce costs and improve efficiency in the transportation industry. This research examined the psychosocial and personality predictors of observed speeding among young drivers. Survey and driving data were collected from 42 newly-licensed teenage drivers during the first 18months of licensure. Speeding (i.e., driving 10mph over the speed limit; about 16km/h) was assessed by comparing speed data collected with recording systems installed in participants' vehicles with posted speed limits. Speeding was correlated with elevated g-force event rates (r=0.335, pb0.05), increased over time, and predicted by day vs. night trips, higher sensation seeking, substance use, tolerance of deviance, susceptibility to peer pressure, and number of risky friends. Perceived risk was a significant mediator of the association between speeding and risky friends. The findings support the contention that social norms may influence teenage speeding behavior and this relationship may operate through perceived risk. Copyright © 2012 National Safety Council and Elsevier Ltd. All rights reserved.

  15. Information and Communication Technology: Students' Health Education in 1st- to 6th-Grade South Korea Elementary Schools

    Science.gov (United States)

    Lee, Eunjoo; Park, Hyejin; Whyte, James; Jeong, Eunhoe

    2013-01-01

    Background: The purposes of this study were to (1) identify school nurses' awareness of information and communication technology (ICT) use in students' health education and (2) explore the barriers or reasons for the adoption of ICT in school nursing practice, while (3) presenting strategies to speed ICT diffusion and dissemination into practice.…

  16. Safety Impact of Average Speed Control in the UK

    DEFF Research Database (Denmark)

    Lahrmann, Harry Spaabæk; Brassøe, Bo; Johansen, Jonas Wibert

    2016-01-01

    of automatic speed control was point-based, but in recent years a potentially more effective alternative automatic speed control method has been introduced. This method is based upon records of drivers’ average travel speed over selected sections of the road and is normally called average speed control...... in the UK. The study demonstrates that the introduction of average speed control results in statistically significant and substantial reductions both in speed and in number of accidents. The evaluation indicates that average speed control has a higher safety effect than point-based automatic speed control....

  17. Variable Speed Rotor System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Variable speed rotors will give helicopters several advantages: higher top speed, greater fuel efficiency, momentary emergency over-power, resonance detuning...

  18. Study of Movement Speeds Down Stairs

    CERN Document Server

    Hoskins, Bryan L

    2013-01-01

    The Study of Movement Speeds Down Stairs closely examines forty-three unique case studies on movement patterns down stairwells. These studies include observations made during evacuation drills, others made during normal usage, interviews with people after fire evacuations, recommendations made from compiled studies, and detailed results from laboratory studies. The methodology used in each study for calculating density and movement speed, when known, are also presented, and this book identifies an additional seventeen variables linked to altering movement speeds. The Study of Movement Speeds Down Stairs is intended for researchers as a reference guide for evaluating pedestrian evacuation dynamics down stairwells. Practitioners working in a related field may also find this book invaluable.

  19. Neural correlates of the difference between working memory speed and simple sensorimotor speed: an fMRI study.

    Directory of Open Access Journals (Sweden)

    Hikaru Takeuchi

    Full Text Available The difference between the speed of simple cognitive processes and the speed of complex cognitive processes has various psychological correlates. However, the neural correlates of this difference have not yet been investigated. In this study, we focused on working memory (WM for typical complex cognitive processes. Functional magnetic resonance imaging data were acquired during the performance of an N-back task, which is a measure of WM for typical complex cognitive processes. In our N-back task, task speed and memory load were varied to identify the neural correlates responsible for the difference between the speed of simple cognitive processes (estimated from the 0-back task and the speed of WM. Our findings showed that this difference was characterized by the increased activation in the right dorsolateral prefrontal cortex (DLPFC and the increased functional interaction between the right DLPFC and right superior parietal lobe. Furthermore, the local gray matter volume of the right DLPFC was correlated with participants' accuracy during fast WM tasks, which in turn correlated with a psychometric measure of participants' intelligence. Our findings indicate that the right DLPFC and its related network are responsible for the execution of the fast cognitive processes involved in WM. Identified neural bases may underlie the psychometric differences between the speed with which subjects perform simple cognitive tasks and the speed with which subjects perform more complex cognitive tasks, and explain the previous traditional psychological findings.

  20. Track treeing mechanism and plastic zone in solid Part 1: Initial development of plastic zone

    International Nuclear Information System (INIS)

    Li Boyang

    2008-01-01

    After neutron exposure and chemical etching in advance, latent tracks of recoil nucleon develop into pits on CR39 surface. During electrochemical etching, plastic zone is formed at top of pits. Some pits develop into tree cracks in the initial stage of plastic zone development. Physical and mathematical model of crack and plastic zone is proposed; parameter of development free path of plastic zone is presented. Based on integration of elementary theories the stress analysis is build up; based on analyses of measured parameters, a set of common relations between parameters is obtained. Integrate parameter analysis and stress analysis, depth of plastic zone development, law and phenomenon in experimental data can be interpreted completely

  1. 77 FR 42176 - Safety Zones; Annual Fireworks Events in the Captain of the Port Detroit Zone

    Science.gov (United States)

    2012-07-18

    ... fireworks launch site located at position 41-34'-18.10'' N, 082-51'-18.70'' W (NAD 83). This zone will be... at position 41-34'-18.10'' N, 082- 51'-18.70'' W (NAD 83). (ii) Expected date. This safety zone will...-AA00 Safety Zones; Annual Fireworks Events in the Captain of the Port Detroit Zone AGENCY: Coast Guard...

  2. Wheel speed management control system for spacecraft

    Science.gov (United States)

    Goodzeit, Neil E. (Inventor); Linder, David M. (Inventor)

    1991-01-01

    A spacecraft attitude control system uses at least four reaction wheels. In order to minimize reaction wheel speed and therefore power, a wheel speed management system is provided. The management system monitors the wheel speeds and generates a wheel speed error vector. The error vector is integrated, and the error vector and its integral are combined to form a correction vector. The correction vector is summed with the attitude control torque command signals for driving the reaction wheels.

  3. Food insecurity, school absenteeism and educational attainment of adolescents in Jimma Zone Southwest Ethiopia: a longitudinal study

    Directory of Open Access Journals (Sweden)

    Gebremariam Abebe

    2011-04-01

    Full Text Available Abstract Background Food insecurity not only affects physical growth and health of children but also their intellectual development, school attendance and academic performance. However, most evidences are based on studies in high income countries. Although food insecurity is common in Ethiopia, to what extent it affects school attendance and educational attainment of adolescents is not explored. We hypothesized that food insecure adolescents would be more likely to be absent from school and have lower grades attained after 1 year compared to their food secure peers. Methods We used data from 2009 adolescents in the age group of 13-17 years from two consecutive surveys of a five year longitudinal family study in Southwest Ethiopia. A stratified random sampling was used to select participants. Regression analyses were used to compare school absenteeism and the highest grade attained after 1 year of follow-up in food secure and insecure adolescents. The analysis was adjusted for demographic factors, reported illness and workload. Results Significantly more (33.0% food insecure adolescents were absent from school compared with their food secure peers (17.8%, P Conclusions Adolescent and household food insecurity are positively associated with school absenteeism and a lower educational attainment. Programs aiming to achieve universal access to primary education in food insecure environments should integrate interventions to ensure food security of adolescents.

  4. Transition to University Life: Insights from High School and University Female Students in Wolaita Zone, Ethiopia

    Science.gov (United States)

    Thuo, Mary; Edda, Medhanit

    2017-01-01

    The purpose of this study was to get an insight about how high school female students perceive the transition to university life, and to understand the transition experience of university female students in the first semester. An exploratory study design was used where 166 high school female students and 88 first year university female students…

  5. Hybrid numerical-experimental optical investigation of the contact zone of ultrasonic motors

    Science.gov (United States)

    Ostasevicius, Vytautas; Palevicius, Arvydas; Ragulskis, Minvydas; Janusas, Giedrius; Pilkauskas, Kestutis

    2005-09-01

    Ultrasonic motors have seen application in areas needing compact, efficient, and intermittent motion. Such applications include: camera auto focus lenses, watch motors, compact paper handling, microrobots, medicine and etc.. They are characterized by high torque at low rotational speed, simple mechanical design and good controllability. Compared with electromagnetic actuators, there is no danger of interference due to electromagnetic induction because no magnetic field is used and ultrasonic motors are more quiet since speed-reduction gears are not required. A polarization vector of the piezoceramic element and location of excitation electrodes on its surface determine the resonance modes of the high frequency vibration exciter. In its turn the modes of vibration play a key role in the functionality of ultrasonic motor. There are analyzed two different regimes of operation--when the contact zone of the resonator performs elliptic and unidirectional motions. Though the mechanical characteristics of the ultrasonic motor in both cases are comparable, detailed analysis of the contact surface shows very different wears. Laser holography is used to identify and control the regimes of motion of actuator. Experimental results are compared with computer simulations. Contact surfaces are analyzed by atomic force microscope (AFM) before experiment, after 10 minutes and after 50 minutes of operation.

  6. SEAL FOR HIGH SPEED CENTRIFUGE

    Science.gov (United States)

    Skarstrom, C.W.

    1957-12-17

    A seal is described for a high speed centrifuge wherein the centrifugal force of rotation acts on the gasket to form a tight seal. The cylindrical rotating bowl of the centrifuge contains a closure member resting on a shoulder in the bowl wall having a lower surface containing bands of gasket material, parallel and adjacent to the cylinder wall. As the centrifuge speed increases, centrifugal force acts on the bands of gasket material forcing them in to a sealing contact against the cylinder wall. This arrangememt forms a simple and effective seal for high speed centrifuges, replacing more costly methods such as welding a closure in place.

  7. Speed test results and hardware/software study of computational speed problem, appendix D

    Science.gov (United States)

    1984-01-01

    The HP9845C is a desktop computer which is tested and evaluated for processing speed. A study was made to determine the availability and approximate cost of computers and/or hardware accessories necessary to meet the 20 ms sample period speed requirements. Additional requirements were that the control algorithm could be programmed in a high language and that the machine have sufficient storage to store the data from a complete experiment.

  8. High speed heterostructure devices

    CERN Document Server

    Beer, Albert C; Willardson, R K; Kiehl, Richard A; Sollner, T C L Gerhard

    1994-01-01

    Volume 41 includes an in-depth review of the most important, high-speed switches made with heterojunction technology. This volume is aimed at the graduate student or working researcher who needs a broad overview andan introduction to current literature. Key Features * The first complete review of InP-based HFETs and complementary HFETs, which promise very low power and high speed * Offers a complete, three-chapter review of resonant tunneling * Provides an emphasis on circuits as well as devices.

  9. Sound Zones

    DEFF Research Database (Denmark)

    Møller, Martin Bo; Olsen, Martin

    2017-01-01

    Sound zones, i.e. spatially confined regions of individual audio content, can be created by appropriate filtering of the desired audio signals reproduced by an array of loudspeakers. The challenge of designing filters for sound zones is twofold: First, the filtered responses should generate...... an acoustic separation between the control regions. Secondly, the pre- and post-ringing as well as spectral deterioration introduced by the filters should be minimized. The tradeoff between acoustic separation and filter ringing is the focus of this paper. A weighted L2-norm penalty is introduced in the sound...

  10. Modern trends in designing high-speed trains

    Directory of Open Access Journals (Sweden)

    Golubović Snežana D.

    2015-01-01

    Full Text Available Increased advantages of railway transportation systems over other types of transportation systems in the past sixty years have been a result of an intensive development of the new generations of high-speed trains. Not only do these types of trains comply with the need for increased speed of transportation and make the duration of the journey shorter, but they also meet the demands for increased reliability, safety and direct application of energy efficiency to the transportation system itself. Along with increased train speed, the motion resistance is increased as well, whereby at speeds over 200 km/h the proportion of air resistance becomes the most dominant member. One of the most efficient measures for reducing air resistance, as well as other negative consequences of high-speed motion, is the development of the aerodynamic shape of the train. This paper presents some construction solutions that affect the aerodynamic properties of high-speed trains, first and foremost, the nose shape, as well as the similarities and differences of individual subsystems necessary for the functioning of modern high-speed rail systems. We analysed two approaches to solving the problem of the aerodynamic shape of the train and the appropriate infrastructure using the examples of Japan and France. Two models of high-speed trains, Shinkansen (Japan and TGV, i.e. AGV (France, have been discussed.

  11. Multiple running speed signals in medial entorhinal cortex

    Science.gov (United States)

    Hinman, James R.; Brandon, Mark P.; Climer, Jason R.; Chapman, G. William; Hasselmo, Michael E.

    2016-01-01

    Grid cells in medial entorhinal cortex (MEC) can be modeled using oscillatory interference or attractor dynamic mechanisms that perform path integration, a computation requiring information about running direction and speed. The two classes of computational models often use either an oscillatory frequency or a firing rate that increases as a function of running speed. Yet it is currently not known whether these are two manifestations of the same speed signal or dissociable signals with potentially different anatomical substrates. We examined coding of running speed in MEC and identified these two speed signals to be independent of each other within individual neurons. The medial septum (MS) is strongly linked to locomotor behavior and removal of MS input resulted in strengthening of the firing rate speed signal, while decreasing the strength of the oscillatory speed signal. Thus two speed signals are present in MEC that are differentially affected by disrupted MS input. PMID:27427460

  12. Radon testing in schools in New York State: a 20-year summary

    International Nuclear Information System (INIS)

    Kitto, Michael

    2014-01-01

    For nearly 20 years the Department of Health has conducted programs to assist in the measurement and reduction of indoor radon concentrations in 186 schools located primarily in Zone 1 areas of New York State. Although many schools had few or no rooms containing radon above 148 Bq/m 3 , some rooms had >740 Bq/m 3 and remediation techniques were utilized to reduce exposure. Short-term radon measurements in the schools showed little correlation to basement and first-floor radon results from single-family homes in the towns. - Highlights: • Relatively few schools in New York State have been tested for indoor radon. • We provide a summary of radon-testing results for measured schools. • The radon potential in schools is often less than in local houses. • Short-term measurement results exceeded their long-term counterparts in nearly every case

  13. Modeling of tropospheric NO2 column over different climatic zones and land use/land cover types in South Asia

    Science.gov (United States)

    ul-Haq, Zia; Rana, Asim Daud; Tariq, Salman; Mahmood, Khalid; Ali, Muhammad; Bashir, Iqra

    2018-03-01

    We have applied regression analyses for the modeling of tropospheric NO2 (tropo-NO2) as the function of anthropogenic nitrogen oxides (NOx) emissions, aerosol optical depth (AOD), and some important meteorological parameters such as temperature (Temp), precipitation (Preci), relative humidity (RH), wind speed (WS), cloud fraction (CLF) and outgoing long-wave radiation (OLR) over different climatic zones and land use/land cover types in South Asia during October 2004-December 2015. Simple linear regression shows that, over South Asia, tropo-NO2 variability is significantly linked to AOD, WS, NOx, Preci and CLF. Also zone-5, consisting of tropical monsoon areas of eastern India and Myanmar, is the only study zone over which all the selected parameters show their influence on tropo-NO2 at statistical significance levels. In stepwise multiple linear modeling, tropo-NO2 column over landmass of South Asia, is significantly predicted by the combination of RH (standardized regression coefficient, β = - 49), AOD (β = 0.42) and NOx (β = 0.25). The leading predictors of tropo-NO2 columns over zones 1-5 are OLR, AOD, Temp, OLR, and RH respectively. Overall, as revealed by the higher correlation coefficients (r), the multiple regressions provide reasonable models for tropo-NO2 over South Asia (r = 0.82), zone-4 (r = 0.90) and zone-5 (r = 0.93). The lowest r (of 0.66) has been found for hot semi-arid region in northwestern Indus-Ganges Basin (zone-2). The highest value of β for urban area AOD (of 0.42) is observed for megacity Lahore, located in warm semi-arid zone-2 with large scale crop-residue burning, indicating strong influence of aerosols on the modeled tropo-NO2 column. A statistical significant correlation (r = 0.22) at the 0.05 level is found between tropo-NO2 and AOD over Lahore. Also NOx emissions appear as the highest contributor (β = 0.59) for modeled tropo-NO2 column over megacity Dhaka.

  14. The Effects of Frontal- and Sagittal-Plane Plyometrics on Change-of-Direction Speed and Power in Adolescent Female Basketball Players.

    Science.gov (United States)

    McCormick, Brian T; Hannon, James C; Newton, Maria; Shultz, Barry; Detling, Nicole; Young, Warren B

    2016-01-01

    Plyometrics is a popular training modality for basketball players to improve power and change-of-direction speed. Most plyometric training has used sagittal-plane exercises, but improvements in change-of-direction speed have been greater in multi-direction programs. To determine the benefits of a 6-wk frontal-plane plyometric (FPP) training program compared with a 6-wk sagittal-plane plyometric (SPP) training program with regard to power and change-of-direction speed. Fourteen female varsity high school basketball players participated in the study. Multiple 2 × 2 repeated-measures ANOVAs were used to determine differences for the FPP and SPP groups from preintervention to postintervention on 4 tests of power and 2 tests of change-of-direction speed. There was a group main effect for time in all 6 tests. There was a significant group × time interaction effect in 3 of the 6 tests. The SPP improved performance of the countermovement vertical jump more than the FPP, whereas the FPP improved performance of the lateral hop (left) and lateral-shuffle test (left) more than the SPP. The standing long jump, lateral hop (right), and lateral-shuffle test (right) did not show a significant interaction effect. These results suggest that basketball players should incorporate plyometric training in all planes to improve power and change-of-direction speed.

  15. Natural and traditional defense mechanisms to reduce climate risks in coastal zones of Bangladesh

    Directory of Open Access Journals (Sweden)

    Mohammed Ataur Rahman

    2015-03-01

    Full Text Available Substantially resourceful and densely populated coastal zones of Bangladesh experience numerous extreme events linked to hydro-meteorological processes viz. cyclones, tidal surges, floods, salinity intrusion and erosion etc. These hazards give rise to extensive damage to property and loss of lives every year. Further, anthropogenic activities in the coastal zones are accentuating environmental degradation causing widespread suffering. Cyclones and tornadoes in particular damage infrastructures and crops every year affecting the economy of the country negatively. Some naturally adapted plants as well as landscapes usually reduce the speed of cyclones and tornadoes and thus, protect the coastal zones. However, human activities have destroyed many of the forests and landscapes. Sundarbans and Chokoria Sundarbans mangrove forests of Bangladesh are under a great threat of extinction due to illicit logging and agricultural expansion. At least 34 plant species of tropical forest are on the verge of extinction. Many animals e.g., cats, bears, porcupines, wild boars, pythons and anteaters are in the process of being wiped out from the coastal areas. Among the marine and coastal species, Red crabs, jelly-fish, sharks, and dolphins are also rare but these were the major species prior to 1980s. This study revealed that during the recent decades there has been massive plantations and construction of embankment and polderization but these and other measures have been found to be impractical and ineffective in reducing disasters in coastal areas. There is a need for integration of traditional coping practices and wisdoms with modern approaches. Available knowledge on some of these traditional practices has been documented for establishing a sustainable policy for management of coastal zones of Bangladesh. By combining traditional and scientific management of coastal ecosystem with mangroves and other plants following triple-tier mechanism and habitat, it is

  16. 33 CFR 165.154 - Safety and Security Zones: Long Island Sound Marine Inspection Zone and Captain of the Port Zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety and Security Zones: Long... Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY... Areas First Coast Guard District § 165.154 Safety and Security Zones: Long Island Sound Marine...

  17. Generalized Geometric Quantum Speed Limits

    Directory of Open Access Journals (Sweden)

    Diego Paiva Pires

    2016-06-01

    Full Text Available The attempt to gain a theoretical understanding of the concept of time in quantum mechanics has triggered significant progress towards the search for faster and more efficient quantum technologies. One of such advances consists in the interpretation of the time-energy uncertainty relations as lower bounds for the minimal evolution time between two distinguishable states of a quantum system, also known as quantum speed limits. We investigate how the nonuniqueness of a bona fide measure of distinguishability defined on the quantum-state space affects the quantum speed limits and can be exploited in order to derive improved bounds. Specifically, we establish an infinite family of quantum speed limits valid for unitary and nonunitary evolutions, based on an elegant information geometric formalism. Our work unifies and generalizes existing results on quantum speed limits and provides instances of novel bounds that are tighter than any established one based on the conventional quantum Fisher information. We illustrate our findings with relevant examples, demonstrating the importance of choosing different information metrics for open system dynamics, as well as clarifying the roles of classical populations versus quantum coherences, in the determination and saturation of the speed limits. Our results can find applications in the optimization and control of quantum technologies such as quantum computation and metrology, and might provide new insights in fundamental investigations of quantum thermodynamics.

  18. Dazzle camouflage affects speed perception.

    Directory of Open Access Journals (Sweden)

    Nicholas E Scott-Samuel

    Full Text Available Movement is the enemy of camouflage: most attempts at concealment are disrupted by motion of the target. Faced with this problem, navies in both World Wars in the twentieth century painted their warships with high contrast geometric patterns: so-called "dazzle camouflage". Rather than attempting to hide individual units, it was claimed that this patterning would disrupt the perception of their range, heading, size, shape and speed, and hence reduce losses from, in particular, torpedo attacks by submarines. Similar arguments had been advanced earlier for biological camouflage. Whilst there are good reasons to believe that most of these perceptual distortions may have occurred, there is no evidence for the last claim: changing perceived speed. Here we show that dazzle patterns can distort speed perception, and that this effect is greatest at high speeds. The effect should obtain in predators launching ballistic attacks against rapidly moving prey, or modern, low-tech battlefields where handheld weapons are fired from short ranges against moving vehicles. In the latter case, we demonstrate that in a typical situation involving an RPG7 attack on a Land Rover the reduction in perceived speed is sufficient to make the grenade miss where it was aimed by about a metre, which could be the difference between survival or not for the occupants of the vehicle.

  19. Green maritime transportation: Speed and route optimization

    DEFF Research Database (Denmark)

    Psaraftis, Harilaos N.; Kontovas, Christos A.

    2015-01-01

    Among the spectrum of logistics-based measures for green maritime transportation, this chapter focuses on speed optimization. This involves the selection of an appropriate speed by the vessel, so as to optimize a certain objective. As ship speed is not fixed, depressed shipping markets and/or high...

  20. Optimal Speed Control for Cruising

    DEFF Research Database (Denmark)

    Blanke, M.

    1994-01-01

    With small profit margins in merchant shipping and more than eighty percent of sailing time being cross ocean voyages, speed control is crucial for vessel profitability......With small profit margins in merchant shipping and more than eighty percent of sailing time being cross ocean voyages, speed control is crucial for vessel profitability...