WorldWideScience

Sample records for freeway corridors part

  1. Modeling of optimal control for urban freeway corridor under incident conditions

    Institute of Scientific and Technical Information of China (English)

    Jianhu ZHENG; Decun DONG

    2006-01-01

    Traffic control and management are effective measures to solve the problem of traffic congestion. The optimal control model for freeway corridor is developed under incident conditions, which is in the form of minimization of the sum of the square of the difference between traffic demand and capacity at each intersection and on the freeway bottleneck section. The model optimizes control parameters of phase splits at arterial intersections, off-ramp diversion rates at upstream off-ramps and on-ramp diversion rates at downstream on ramps. Finally, the objective function is discussed and it is showed that the optimal control model is simple and practical.

  2. Vehicle-class Specific Control of Freeway Traffic

    NARCIS (Netherlands)

    Schreiter, T.

    2013-01-01

    The increase of mobility of the past decades has led to substantial congestion on the freeways. Traffic jams emerge both on a daily basis at the same location, as well as during accidents when a part of the freeways is temporarily blocked. In those cases, traffic management centers intervene into tr

  3. 14 CFR Appendix A to Part 420 - Method for Defining a Flight Corridor

    Science.gov (United States)

    2010-01-01

    ... method, a semi-automated method, or a fully-automated method to plot a flight corridor on maps. A source... Administration, National Ocean Service. (i) Projections for mechanical plotting method. An applicant shall use a... plotting method. An applicant shall use cylindrical, conic, or plane projections for...

  4. From corridor to region

    DEFF Research Database (Denmark)

    Jensen, Anne; Jespersen, Per Homann

    2006-01-01

    The corridor between Oslo and Berlin is by the politicians of the regional authorities in the Scandinavian part of the corridor seen a region with unique qualities and a large innovation and growth potential. In order to explore and develop this potential an In-terreg project has been launched. E...... this task by applying principles of participative planning and with action research methodology are involving stakeholders in the process of defining, developing and disseminating the idea of the Corridor of Innovation and Cooperation - COINCO.......The corridor between Oslo and Berlin is by the politicians of the regional authorities in the Scandinavian part of the corridor seen a region with unique qualities and a large innovation and growth potential. In order to explore and develop this potential an In-terreg project has been launched...

  5. Exploring the impact of a coordinated variable speed limit control on congestion distribution in freeway

    Directory of Open Access Journals (Sweden)

    Jing Cao

    2015-06-01

    Full Text Available Over the past few decades, urban freeway congestion has been highly recognized as a serious and worsening traffic problem in the world. To relieve freeway congestion, several active traffic and demand management (ATDM methods have been developed. Among them, variable speed limit (VSL aims at regulating freeway mainline flow upstream to meet existing capacity and to harmonize vehicle speed. However, congestion may still be inevitable even with VSL implemented due to extremely high demand in actual practice. This study modified an existing VSL strategy by adding a new local constraint to suggest an achievable speed limit during the control period. As a queue is a product of the congestion phenomenon in freeway, the incentives of a queue build-up in the applied coordinated VSL control situation were analyzed. Considering a congestion occurrence (a queue build-up characterized by a sudden and sharp speed drop, speed contours were utilized to demonstrate the congestion distribution over a whole freeway network in various scenarios. Finally, congestion distributions found in both VSL control and non-VS control situations for various scenarios were investigated to explore the impact of the applied coordinated VSL control on the congestion distribution. An authentic stretch of Whitemud Drive (WMD, an urban freeway corridor in Edmonton, Alberta, Canada, was employed to implement this modified coordinated VSL control strategy; and a calibrated micro-simulation VISSIM model (model functions was applied as the substitute of the real-world traffic system to test the above mentioned performance. The exploration task in this study can lay the groundwork for future research on how to improve the presented VSL control strategy for achieving the congestion mitigation effect on freeway.

  6. Impacts of Left Lane Truck Restriction on Urban Freeways

    OpenAIRE

    Yang, Choon-Heon; Regan, A C

    2007-01-01

    This paper examines the impacts of truck lane restriction on urban freeways using traffic simulation models. The study includes three main parts: Part (1) provides insights into conditions under which truck lane restrictions would work well; Part (2) identifies the best number of lanes to restrict and shows that this is an important factor in the success of lane restriction; Part (3) investigates potential impacts of truck lane restriction through a case study using a region with some of the ...

  7. Inproved grade length limitation of freeways

    Institute of Scientific and Technical Information of China (English)

    XING En-hui; PEI Yu-long

    2006-01-01

    A method of ascertaining grade length limitation of freeways in mountain terrain is presented. The relationship models between 15th percentile speeds and grades were built through the surveys and analyses of operation speeds on 7 typical sections of 3 freeways in mountain terrain. Using 15th percentile and 85th percentile as speed limitations, the methods of determining admitted velocities were put forward according to the grades. Deceleration distances of longitudinal slopeways were analyzed utilizing the theories of vehicle. According to the results of analysis, grade length limitation was loosed. Finally the values of grade length limitation for freeways were put forward. The results could be used as references for freeway design.

  8. From corridor to region

    DEFF Research Database (Denmark)

    Jensen, Anne; Jespersen, Per Homann

    2006-01-01

    The corridor between Oslo and Berlin is by the politicians of the regional authorities in the Scandinavian part of the corridor seen a region with unique qualities and a large innovation and growth potential. In order to explore and develop this potential an In-terreg project has been launched. E...... this task by applying principles of participative planning and with action research methodology are involving stakeholders in the process of defining, developing and disseminating the idea of the Corridor of Innovation and Cooperation - COINCO....

  9. Statistical analysis of aggregation in freeway traffic

    Institute of Scientific and Technical Information of China (English)

    Li Jun-Wei; Lin Bo-Liang; Huang Yong-chang

    2007-01-01

    We restudy the master-equation approach to aggregation in freeway traffic based on the theory of birth-death process,in which the clustering behaviour in one-lane freeway traffic model is investigated.The transition probabilities for the jump processes are reconstructed by using Greenshields'model,and the equation of the mean size of the cluster at any time t is derived from the birth-death equation.Numerical experiments show the clustering behaviours varying with time very well.

  10. Study of Freeway Traffic Near an Off-Ramp

    OpenAIRE

    Cassidy, Michael J.; Anani, Shadi B.; Haigwood, John M.

    2000-01-01

    A bottleneck with a diminished capacity is shown to have arisen on a freeway segment whenever queues from the segment's off-ramped spilled over and occupied its mandatory exit lane. It is also shown that longer exit queues from the over-saturate off-ramp were accompanied by lower discharge rates for non-exiting vehicles. The explanation appears to be rubber-necking on the part of the non-exiting drivers. Whenever the of-ramp queues were prevented from spilling over to the exit lane (by changi...

  11. Impact of traffic states on freeway crash involvement rates.

    Science.gov (United States)

    Yeo, Hwasoo; Jang, Kitae; Skabardonis, Alexander; Kang, Seungmo

    2013-01-01

    Freeway traffic accidents are complicated events that are influenced by multiple factors including roadway geometry, drivers' behavior, traffic conditions and environmental factors. Among the various factors, crash occurrence on freeways is supposed to be strongly influenced by the traffic states representing driving situations that are changed by road geometry and cause the change of drivers' behavior. This paper proposes a methodology to investigate the relationship between traffic states and crash involvements on the freeway. First, we defined section-based traffic states: free flow (FF), back of queue (BQ), bottleneck front (BN) and congestion (CT) according to their distinctive patterns; and traffic states of each freeway section are determined based on actual measurements of traffic data from upstream and downstream ends of the section. Next, freeway crash data are integrated with the traffic states of a freeway section using upstream and downstream traffic measurements. As an illustrative study to show the applicability, we applied the proposed method on a 32-mile section of I-880 freeway. By integrating freeway crash occurrence and traffic data over a three-year period, we obtained the crash involvement rate for each traffic state. The results show that crash involvement rate in BN, BQ, and CT states are approximately 5 times higher than the one in FF. The proposed method shows promise to be used for various safety performance measurement including hot spot identification and prediction of the number of crash involvements on freeway sections.

  12. Upper Kenai Corridor Study

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Upper Kenai Corridor study describes and evaluates the Upper Kenai River and the land which embraces it. It also places the river corridor in its regional...

  13. Corridor use by Asian elephants.

    Science.gov (United States)

    Pan, Wenjing; Lin, Liu; Luo, Aidong; Zhang, Li

    2009-06-01

    There are 18 km of Kunming-Bangkok Highway passing through the Mengyang Nature Reserve of Xishuangbanna National Nature Reserve in Yunnan Province, China. From September 2005 to September 2006 the impact of this highway on movement of wild Asian elephants between the eastern and western part of the nature reserve was studied using track transecting, rural surveys and direct monitoring. Our results showed that the number of crossroad corridors used by Asian elephants diminished from 28 to 23 following the construction of the highway. In some areas, the elephant activity diminished or even disappeared, which indicated a change in their home ranges. The utilization rate of artificial corridors was 44%. We also found that elephants preferred artificial corridors that were placed along their original corridors. During the research, wild elephants revealed their adaptation to the highway. They were found walking across the highway road surface many times and for different reasons. We suggest that the highway management bureau should revise their management strategies to mitigate the potential risks caused by elephants on the road for the safety of the public and to protect this endangered species from harm. It is also very important to protect and maintain current Asian elephants corridors in this region.

  14. Economic analysis of freeway town of Yunnan

    Institute of Scientific and Technical Information of China (English)

    Zhao Junquan; Zhang Haixiang

    2009-01-01

    Freeway town in Yunnan is driving to promote the economic development ties.The development along the highway in the town will become the central point of the performance the high-intensive economy in space and will increase new economic growth point along highway the vertical and horizontal development of the area around the gradient the proliJeration Point and Area.The highway town will develop to speed up the urbanization process and China should accelerate the development of the freeway town.Encouraging farmers will shift the highway town where some good conditions will build to.form a regional economic development and growth.This will be the promotion an inevitable choice of progress and rational way of China's rural economic" and social prosperity.In particular,freeway town will bring more added value of other social services of accommodation and catering industry of wholesale and retail of transportation and warehousing.Highway town and agriculture industrialization development will increase agriculture industry chain to improve agricultural products value and will enhance agricultural efficiency in Yunnan.The concentration of the non-agricultural industries of the speedway town will form pillar industries of highway town and will promote of tertiary industry development of hotels of insurance of finance of business of sports of culture of education of communications of transportation.Rural areas of Yunnan will adjust to optimize the industrial structure.It is estimated that a total 10 construction of the highway town of Yunnan will increase 0.8-1 billion )man revenue each year.

  15. VT Electric Transmission Line Corridors - corridor lines

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The ELTRN layer depicts electric transmission line corridors in Vermont. Various methods have been used to digitize features. The data layer...

  16. Adsorption of heavy metal in freeway by asphalt block

    Science.gov (United States)

    Zheng, Chaocheng

    2017-08-01

    Heavy metals are toxic, persistent, and carcinogenic in freeway. Various techniques are available for the removal of heavy metals from waste water among soils during freeway including ion-exchange, membrane filtration, electrolysis, coagulation, flotation, and adsorption. Among them, bio-sorption processes are widely used for heavy metal and other pollutant removal due to its sustainable, rapid and economic. In this paper, heavy metal removal facilitated by adsorption in plants during freeway was illustrated to provide concise information on exploring the adsorption efficiency.

  17. Green corridors basics

    DEFF Research Database (Denmark)

    Panagakos, George

    2016-01-01

    The purpose of this chapter is to introduce the concept of ‘green corridors’ as a means to develop integrated, efficient and environmentally friendly transportation of freight between major hubs and by relative long distances. The basis of this material is work conducted in the context of the EU...... SuperGreen project, which aimed at advancing the green corridor concept through a benchmarking exercise involving Key Performance Indicators (KPIs). The chapter discusses the available definitions of green corridors and identifies the characteristics that distinguish a green corridor from any other...... efficient surface transportation corridor. After providing examples of green corridor projects in Europe, it focuses on the KPIs that have been proposed by various projects for monitoring the performance of a freight corridor. Emphasis is given to the SuperGreen KPIs, covering the economic, technical...

  18. Living near a Freeway is Associated with Lower Bone Mineral Density among Mexican Americans

    Science.gov (United States)

    Chen, Zhanghua; Salam, Muhammad T.; Karim, Roksana; Toledo-Corral, Claudia M.; Watanabe, Richard M.; Xiang, Anny H.; Buchanan, Thomas A.; Habre, Rima; Bastain, Theresa M.; Lurmann, Fred; Taher, Maryam; Wilson, John P.; Trigo, Enrique; Gilliland, Frank D.

    2015-01-01

    Purpose Adults residing in rural areas have been linked with higher bone mineral density (BMD). We aimed to determine if this difference is due in part to air pollution by examining the relationships between traffic metrics and ambient air pollution with total body and pelvic BMD. Methods Mexican-American adults (n=1,175; mean 34 years; 72% female) who had participated in the BetaGene study of air pollution, obesity and insulin resistance were included in this analysis. Total body and pelvic BMD were estimated using dual-energy X-ray absorptiometry. Traffic and ambient air pollutant exposures were estimated at residences using location and ambient monitoring data. Variance component models were used to analyze the associations between residential distance to the nearest freeway and ambient air pollutants with BMD. Results Residential proximity to a freeway was associated with lower total body BMD (p-trend=0.01) and pelvic BMD (p-trend=0.03) after adjustment for age, sex, weight and height. The adjusted mean total body and pelvic BMD in participants living within 500m of a freeway were 0.02 g/cm2 and 0.03 g/cm2 lower than participants living greater than 1,500m from a freeway. These associations did not differ significantly by age, sex or obesity status. Results were similar after further adjustment for body fat and weekly physical activity minutes. Ambient air pollutants (NO2, O3 and PM2.5) were not significantly associated with BMD. Conclusions Traffic-related exposures in overweight and obese Mexican-Americans may adversely affect BMD. Our findings indicate that long-term exposures to traffic may contribute to the occurrence of osteoporosis and its consequences. PMID:25677718

  19. Road and Street Centerlines, h143 corridor - Hwy 143 corridor, Published in 2007, 1:24000 (1in=2000ft) scale, Iron County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — , published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2007. It is described as 'h143 corridor - Hwy 143 corridor'. The...

  20. Drivers’ Visual Search Patterns during Overtaking Maneuvers on Freeway

    Directory of Open Access Journals (Sweden)

    Wenhui Zhang

    2016-11-01

    Full Text Available Drivers gather traffic information primarily by means of their vision. Especially during complicated maneuvers, such as overtaking, they need to perceive a variety of characteristics including the lateral and longitudinal distances with other vehicles, the speed of others vehicles, lane occupancy, and so on, to avoid crashes. The primary object of this study is to examine the appropriate visual search patterns during overtaking maneuvers on freeways. We designed a series of driving simulating experiments in which the type and speed of the leading vehicle were considered as two influential factors. One hundred and forty participants took part in the study. The participants overtook the leading vehicles just like they would usually do so, and their eye movements were collected by use of the Eye Tracker. The results show that participants’ gaze durations and saccade durations followed normal distribution patterns and that saccade angles followed a log-normal distribution pattern. It was observed that the type of leading vehicle significantly impacted the drivers’ gaze duration and gaze frequency. As the speed of a leading vehicle increased, subjects’ saccade durations became longer and saccade angles became larger. In addition, the initial and destination lanes were found to be key areas with the highest visual allocating proportion, accounting for more than 65% of total visual allocation. Subjects tended to more frequently shift their viewpoints between the initial lane and destination lane in order to search for crucial traffic information. However, they seldom directly shifted their viewpoints between the two wing mirrors.

  1. Metro Conservation Corridors

    Data.gov (United States)

    Minnesota Department of Natural Resources — The Metro Conservation Corridors (MeCC) grow out of the natural resource analysis work done by the DNR in the late '90's, documented in the Metro Greenprint...

  2. Shear zone junctions: Of zippers and freeways

    Science.gov (United States)

    Passchier, Cees W.; Platt, John P.

    2017-02-01

    Ductile shear zones are commonly treated as straight high-strain domains with uniform shear sense and characteristic curved foliation trails, bounded by non-deforming wall rock. Many shear zones, however, are branched, and if movement on such branches is contemporaneous, the resulting shape can be complicated and lead to unusual shear sense arrangement and foliation geometries in the wall rock. For Y-shaped shear zone triple junctions with three joining branches and transport direction at a high angle to the branchline, only eight basic types of junction are thought to be stable and to produce significant displacement. The simplest type, called freeway junctions, have similar shear sense in all three branches. The other types show joining or separating behaviour of shear zone branches similar to the action of a zipper. Such junctions may have shear zone branches that join to form a single branch (closing zipper junction), or a single shear zone that splits to form two branches, (opening zipper junction). All categories of shear zone junctions show characteristic foliation patterns and deflection of markers in the wall rock. Closing zipper junctions are unusual, since they form a non-active zone with opposite deflection of foliations in the wall rock known as an extraction fault or wake. Shear zipper junctions can form domains of overprinting shear sense along their flanks. A small and large field example are given from NE Spain and Eastern Anatolia. The geometry of more complex, 3D shear zone junctions with slip parallel and oblique to the branchline is briefly discussed.

  3. The Corridor Chronicles. Integrated perspectives on European transport corridor development

    NARCIS (Netherlands)

    Witte, P.A.

    2014-01-01

    This dissertation aims to clarify the added value of an integrated perspective on corridor development in Europe. For many years, knowledge on corridors has been developed in a sectoral, technocratic manner, despite a growing call for an integrated analysis of corridor issues. The integration argume

  4. River Corridors (Jan 2, 2015)

    Data.gov (United States)

    Vermont Center for Geographic Information — River corridors are delineated to provide for the least erosive meandering and floodplain geometry toward which a river will evolve over time. River corridor maps...

  5. Road and Street Centerlines, Average Freeway/Arterial/Low Speed Arterial Travel Speeds - Spring and Fall 2010 Data collected during PM Peak period (4:30 - 6:30pm) and AM Peak Period (7 - 9am) on selected roadways - GPS travel speeds at 1,000 ft interval, Published in 2010, 1:2400 (1in=200ft) scale, Baltimore Metropolitan Council.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — , published at 1:2400 (1in=200ft) scale, was produced all or in part from Field Survey/GPS information as of 2010. It is described as 'Average Freeway/Arterial/Low...

  6. The final girl on the freeway: Adaptation and appropriation of a fairy tale

    Directory of Open Access Journals (Sweden)

    James Kloda

    2016-06-01

    Full Text Available Fairy tales and their adaptations transgress established social, cultural and temporal boundaries. This paper examines Matthew Bright’s Freeway (1996, an adaptation of Little Red Riding Hood that deliberately mirrors this transgression by setting the film within the generic type of horror cinema. In choosing this mode, Bright partly restores the fairy tale to its original purpose, once existing as a folktale full of high melodrama, but goes further, criticising the text of ‘known pattern’ and overhauling it to a story in which an innocent female under attack restores her own equilibrium: in effect, deploying the ‘final girl’ trope that is common in slasher movies. Freeway uses its adaptive status to radically reinterpret the source text, fomenting its oppositional assault through a genre most suited to subversion. Through textual analysis, the paper examines how Bright harnesses the potential of the cinematographic medium through a double interaction, one that not only allows a coded opening of the internal, intertextual space of the adaptation, but also an antagonistic encounter rooted in the context of horror cinema.

  7. Implementation of Advanced Techniques for Automated Freeway Incident Detection

    OpenAIRE

    Abdulhai, Baher; Ritchie, Stephen G.; Iyer, Mahadevan

    1999-01-01

    A significant body of research on advanced techniques for automated freeway incident detection has been conducted at the University of California, Irvine (UCI). Such advanced pattern recognition techniques as artificial neural networks (ANNs) have been thoroughly investigated and their potential superiority to other techniques has been demonstrated. Of the investigated ANN architectures, two have shown the best potential for real-time implementation: namely, the Probabilistic Neural Network (...

  8. Estimation of Crash Severity on Mountainous Freeways in Chongqing

    Directory of Open Access Journals (Sweden)

    Yunwei Meng

    2017-01-01

    Full Text Available Mountainous freeways always suffer from accidents due to special terrain, weather conditions, driving environment, and so on. Based on the records of 898 accidents that occurred on mountainous freeways in Chongqing during the past 6 years, the partial proportional odds model is used to identify the factors affecting the accident severity. The time of the accident, season, involvement of trucks, accident characteristics, speeding, maximum driving experience of involved drivers, and weather and road conditions are found to be important for the levels of accident severity. Zero to 6 a.m. and 19 to 24 p.m. are the times prone to serious traffic accidents. The probability of serious traffic accidents in summer and autumn is greater than that in spring and winter. Once a truck is involved in an accident, the consequence is often more severe. Turnover and speeding will result in a grave accident. When there is an experienced driver, the probability of serious traffic accidents is low. The fog is extremely unfavorable weather conditions. The probability of serious accident happening in the downgrade, ramp, curve, bridge, and tunnel sections is greater than the others. The results aim to provide valuable reference for traffic safety on mountainous freeways.

  9. Green corridors and network design

    DEFF Research Database (Denmark)

    Panagakos, George

    2016-01-01

    The purpose of this chapter is to investigate the relation between the Trans-European Transport Network (TEN-T) and the green corridor concept. First, the need is established for a corridor governance structure that enables the close cooperation among the numerous stakeholders from both the public...... and private sectors engaged in all corridor related issues ranging from network design to the provision of integrated logistical solutions. The governance scheme of the recently introduced TEN-T core network corridors seems to fulfil this requirement. Following a brief history of TEN-T development, the 2013...... major overhaul of the EU transportation infrastructure policy is outlined and the basic differences with the past are pinpointed. The provisions of the new TEN-T Guidelines are scrutinized so as to check whether the TEN-T core network corridors exhibit the characteristics of a green corridor...

  10. Corridor use by diverse taxa.

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, Nick, M.; Browne, David, R.; Cunningham, Alan; Danielson, Brent, J.; Levey, Douglas, J.; Sargent, Sarah; Spira, Tim

    2003-01-01

    Haddad, N.M., D.R. Browne, A. Cunningham, B.J. Danielson, D.J. Levey, S. Sargent, and T. Spira. 2003. Corridor use by diverse taxa. Ecology, 84(3):609-615. One of the most popular approaches for maintaining populations and conserving biodiversity in fragmented landscapes is to retain or create corridors that connect otherwise isolated habitat patches. Working in large-scale, experimental landscapes in which open-habitat patches and corridors were created by harvesting pine forest, we showed that corridors direct movements of different types of species, including butterflies, small mammals, and bird dispersed plants, causing higher movement between connected than between unconnected patches. Corridors directed the movement of all 10 species studied, with all corridor effect sizes >68%. However, this corridor effect was significant for five species, not significant for one species, and inconclusive for four species because of small sample sizes. Although we found no evidence that corridors increase emigration from a patch, our results show that movements of disparate taxa with broadly different life histories and functional roles are directed by corridors.

  11. Particulate Matter Concentrations in East Oakland's High Street Corridor

    Science.gov (United States)

    Lei, P.; Jackson, J.; Lewis, R.; Marigny, A.; Mitchell, J. D.; Nguyen, R.; Philips, B.; Randle, D.; Romero, D.; Spears, D.; Telles, C.; Weissman, D.

    2012-12-01

    Particulate matter (PM) is a complex mixture of small solid pieces and/or liquid droplets in the air. High concentrations of PM can pose a serious health hazard because inhalation can result in breathing problems and/or aggravate asthma. Long term exposure can increase the likelihood of respiratory problems like asthma and emphysema as well as cancer. The smaller the particles, the deeper they can get into the respiratory system. For this reason, the smallest particles, those smaller than 2.5 micrometers in diameter (PM2.5), are the most dangerous. PM2.5 is largely emitted from motor vehicles burning fuels that don't break down fully. Our research team investigated the levels of PM2.5 as well as particles smaller than 10 micrometers (PM10) and total suspended particulate (TSP) along the northeast-southwest trending High Street Corridor, near Fremont High School in East Oakland, California. Using the Aerocet 531 mass particle counter, team members walked through neighborhoods and along major roads within a 1 mile radius of Fremont High School. The Aerocet 531 recorded two minute average measurements of all the relevant PM sizes, which are reported in mg/m3. Measurements were consistently taken in the morning, between 8:30 and 11:30 am. Preliminary results indicate maximum readings of all PM sizes at sites that are in close proximity to a major freeway (Interstate-880). These results support our initial hypothesis that proximity to major roads and freeways, especially those with high diesel-fuel burning truck traffic, would be the primary factor affecting PM concentration levels. Preliminary median and maximum readings all suggest particulate matter levels below what the EPA would consider unhealthy or risky.

  12. Green corridors in freight logistics

    DEFF Research Database (Denmark)

    Panagakos, George

    The subject of this thesis is ‘green corridors,’ a European concept denoting a concentration of freight traffic between major hubs and by relatively long distances. Since their inception in 2007, green corridors have gained popularity as a policy tool that enhances the overall environmental susta...

  13. A COMPARATIVE ANALYSIS OF INCIDENT SERVICE TIME ON URBAN FREEWAYS

    Directory of Open Access Journals (Sweden)

    Hyung Jin KIM, Ph.D.

    2001-01-01

    In this study, a fuzzy incident response model is formulated in terms of incident, type of vehicle, type of incident vehicle, location of incident vehicle, and incident service time. In order to analyze the reliability of the proposed model, the application of the model is made using the actual incident data collected on the freeway in the Los Angeles area. The application of the model shows that the fuzzy incident response system is very effective in describing the actual judgment of the incident operators in terms of incident service time.

  14. A Green Corridor Balanced Scorecard

    Directory of Open Access Journals (Sweden)

    Prause Gunnar

    2014-12-01

    Full Text Available Green transport corridors represent trans-shipment routes with a concentration of freight traffic between major hubs and long distances of transport marked by reduced environmental and climate impact. Important characteristics of green corridors are their network structures, their transnational character and their high involvement of public and private stakeholders, including political level requiring new governance models. Network-oriented controlling of green transport corridors require new concepts and instruments concentrating on multi-dimensional evaluation of collective strategies and processes in an international environment with a focus on cross-company aspects.

  15. Analysis on distribution of freeway accidents under various conditions in China

    Directory of Open Access Journals (Sweden)

    Xiaofei Wang

    2016-08-01

    Full Text Available This study aims to provide a current survey on the situation of freeway accidents in China. The results show that the accident rate, death toll, injury toll, and direct loss of property are 3.2, 8.4, 7.2, and 24.3 times that of the average for an ordinary highway in China. Freeway accidents occur mainly in Southern (20.77% and Central (20.2% China. With detailed data from Guangdong Province, the number of accidents in freeways with 80 km/h design speed (29.58/km/103 pcu was more than three times that in freeways with design speed of 100 km/h (9.54/km/103 pcu and 120 km/h (9.42/km/103 pcu. The total accident rate increased monotonously with the decrease in horizontal radius. The results indicate that 54.54% (/km/103 pcu of accidents occurred on a steep slope (4%–5%, representing about 10 times that of 3%–4% slope and 20 times that of the less than 3% slope. Based on the data, the safety situation of China’s highway transportation is obviously grim, and improving freeway heavy traffic management in economically developed regions, strengthening the safeguarding of mountain freeways, applying small radius and large vertical grade with caution, and developing a monitoring system of tunnels and interchanges could be used as effective measures to prevent freeway accidents.

  16. Evacuation from smoke filled corridors

    NARCIS (Netherlands)

    Janse, E.W.; Leur, P.H.E. van de; Oerle, N.J. van

    1998-01-01

    underpinning compartmentation requirements in the Dutch regulations is that people can and will go through 30 m of smoke filled space. The hypothesis leads to the requirement that corridors are divided in compartments with a maximum length of 30 meters.

  17. Operational performance of a congested corridor with lanes dedicated to autonomous vehicle traffic

    Directory of Open Access Journals (Sweden)

    Zachary Vander Laan

    2017-06-01

    Full Text Available This paper considers the operational performance impact of autonomous vehicles (AV on a multi-lane freeway corridor with separate lanes dedicated to AV and non-AV traffic. Autonomous vehicle behavior is modeled at the macroscopic level by modifying the fundamental diagram relating hourly traffic flow and vehicle density, a step that is justified by adjusting a parameter from Newell’s car-following model at the microscopic level and transforming back to a macroscopic representation. The model is applied to the I-95 corridor between Washington, DC and Baltimore, MD during the PM peak period, where the impact of introducing a managed AV-only lane is assessed at varying penetration rates of autonomous vehicles. The results show that the overall corridor performance metrics improve with increasing penetration rates up to 30%, 40% or 50% (depending on the underlying assumptions that govern AV behavior, after which the performance deteriorates drastically. Implications of the results are discussed in light of the per-lane and aggregated metrics, and future directions for research are proposed.

  18. Robust identification for multi-section freeway traffic models

    Institute of Scientific and Technical Information of China (English)

    Zhongke SHI

    2005-01-01

    Since it is difficult to fit measured parameters using the conventional traffic model, a new traffic density and average speed model is introduced in this paper.To determine traffic model structures accurately, a model identification method for uncertain nonlinear system is developed.To simplify uncertain nonlinear problem, this paper presents a new robust criterion to identify the multi-section traffic model structure of freeway efficiently.In the new model identification criterion,numerically efficient U-D factorization is used to avoid computing the determinant values of two complex matrices.By estimating the values of U-D factor of data matrix, both the upper and lower bounds of system uncertainties are described. Thus a model structure identification algorithm is proposed.Comparisons between identification outputs and simulation outputs of traffic states show that the traffic states can be accurately predicted by means of the new traffic models and the structure identification criterion.

  19. Capacity of Freeway Merge Areas with Different On-Ramp Traffic Flow

    Directory of Open Access Journals (Sweden)

    Jinxing Shen

    2015-06-01

    Full Text Available This paper is aimed at investigating the influence of different types of traffic flows on the capacity of freeway merge areas. Based on the classical gap-acceptance model, two calculating models were established specifically considering randomly arriving vehicles and individual difference in driving behaviours. Monte-Carlo simulation was implemented to reproduce the maximum traffic volume on the designed freeway merge area under different situations. The results demonstrated that the proposed calculating models have better performance than the conventional gap-acceptance theory on accurately predicting the capacity of freeway merge areas. The findings of research could be helpful to improve the microscopic traffic flow simulation model from a more practical perspective and support the designing of freeway merge areas as well.

  20. As I ride the late night freeways (2014-15) For soprano and orchestra

    OpenAIRE

    2015-01-01

    As I ride the late night freeways is a work for soprano and orchestra. The music is a setting of Census, a poem by Cathy Park Hong written specifically for this project. The score engages the notion of California freeway driving to suggest compositional processes and musical parameters to unify the musical work. Ideas derived from the parametric aesthetic provide a significant “streamlining” influence, echoed in the development of musical processes that take a variety of forms: from harmonic ...

  1. Bayesian random effect models incorporating real-time weather and traffic data to investigate mountainous freeway hazardous factors.

    Science.gov (United States)

    Yu, Rongjie; Abdel-Aty, Mohamed; Ahmed, Mohamed

    2013-01-01

    Freeway crash occurrences are highly influenced by geometric characteristics, traffic status, weather conditions and drivers' behavior. For a mountainous freeway which suffers from adverse weather conditions, it is critical to incorporate real-time weather information and traffic data in the crash frequency study. In this paper, a Bayesian inference method was employed to model one year's crash data on I-70 in the state of Colorado. Real-time weather and traffic variables, along with geometric characteristics variables were evaluated in the models. Two scenarios were considered in this study, one seasonal and one crash type based case. For the methodology part, the Poisson model and two random effect models with a Bayesian inference method were employed and compared in this study. Deviance Information Criterion (DIC) was utilized as a comparison factor. The correlated random effect models outperformed the others. The results indicate that the weather condition variables, especially precipitation, play a key role in the crash occurrence models. The conclusions imply that different active traffic management strategies should be designed based on seasons, and single-vehicle crashes have different crash mechanism compared to multi-vehicle crashes.

  2. 76 FR 41929 - Patient Protection and Affordable Care Act; Standards Related to Reinsurance, Risk Corridors and...

    Science.gov (United States)

    2011-07-15

    ... Affordable Care Act; Standards Related to Reinsurance, Risk Corridors and Risk Adjustment; Proposed Rule #0... OF HEALTH AND HUMAN SERVICES 45 CFR Part 153 RIN 0938-AR07 Patient Protection and Affordable Care Act... corridors, and risk adjustment consistent with title I of the Patient Protection and Affordable Care Act...

  3. Argali Sheep (Ovis ammon Movement Corridors Between Critical Resources in Ikh Nart Nature Reserve, Mongolia

    Directory of Open Access Journals (Sweden)

    James D. Murdoch

    2017-05-01

    Full Text Available Understanding how animals move through a landscape can reveal corridors or narrow paths of movement that connect discrete parts of a landscape. Identifying corridors can be important for planning conservation activities, especially for threatened species. We synthesized information on the ranging behavior and distribution of argali sheep to quantify linkages and potential pinch points of movement between critical resources in Ikh Nart Nature Reserve, Mongolia. We used a cost-weighted distance approach to quantify the relative cost of movement between water sources (springs, which represent critical resources. We used values to map a corridor of movement and examined movement fl ow through the corridor using a circuit theory approach. We identifi ed a corridor connecting all springs that covered 50.6 km2 . Most of the corridor overlapped the reserve (77% and reserve’s core area (62%. A least-cost path between the furthest separated springs (18 km was 26.4 km. Most movement fl ow through the corridor concentrated around springs, especially those in the southern and central portions of the corridor. The analysis also revealed several pinch points that represent a conservation concern. We recommend prioritizing activities at pinch points and extending protected area boundaries to encompass all springs to eff ectively protect the entire corridor.

  4. Use of Individual Flight Corridors to Avoid Vortex Wakes

    Science.gov (United States)

    Rossow, Vernon J.

    2001-01-01

    Vortex wakes of aircraft pose a hazard to following aircraft until the energetic parts of their flow fields have decayed to a harmless level. It is suggested here that in-trail spacings between aircraft can be significantly and safely reduced by designing an individual, vortex-free flight corridor for each aircraft. Because each aircraft will then have its own flight corridor, which is free of vortex wakes while in use by the assigned aircraft, the time intervals between aircraft operations can be safely reduced to the order of seconds. The productivity of airports can then be substantially increased. How large the offset distances between operational corridors need to be to have them vortex free, and how airports need to be changed to accommodate an individual flight-corridor process for landing and takeoff operations, are explored. Estimates are then made of the productivity of an individual flight-corridor system as a function of the in-trail time interval between operations for various values of wake decay time, runway width, and the velocity of a sidewind. The results confirm the need for short time intervals between aircraft operations if smaller offset distances and increased productivity are to be achieved.

  5. Capitalizing on spatiality in European transport corridors

    NARCIS (Netherlands)

    Witte, P.A.; van Oort, F.G.; Wiegmans, B.; Spit, T.J.M.

    2013-01-01

    After half a century of corridor development in Europe, the corridor concept is well-established in the academic discourse on transportation. Transport corridors have also been common practice in European transport policy since the creation of a borderless Europe in the 1990s. What is largely lackin

  6. Hazard based models for freeway traffic incident duration.

    Science.gov (United States)

    Tavassoli Hojati, Ahmad; Ferreira, Luis; Washington, Simon; Charles, Phil

    2013-03-01

    Assessing and prioritising cost-effective strategies to mitigate the impacts of traffic incidents and accidents on non-recurrent congestion on major roads represents a significant challenge for road network managers. This research examines the influence of numerous factors associated with incidents of various types on their duration. It presents a comprehensive traffic incident data mining and analysis by developing an incident duration model based on twelve months of incident data obtained from the Australian freeway network. Parametric accelerated failure time (AFT) survival models of incident duration were developed, including log-logistic, lognormal, and Weibul-considering both fixed and random parameters, as well as a Weibull model with gamma heterogeneity. The Weibull AFT models with random parameters were appropriate for modelling incident duration arising from crashes and hazards. A Weibull model with gamma heterogeneity was most suitable for modelling incident duration of stationary vehicles. Significant variables affecting incident duration include characteristics of the incidents (severity, type, towing requirements, etc.), and location, time of day, and traffic characteristics of the incident. Moreover, the findings reveal no significant effects of infrastructure and weather on incident duration. A significant and unique contribution of this paper is that the durations of each type of incident are uniquely different and respond to different factors. The results of this study are useful for traffic incident management agencies to implement strategies to reduce incident duration, leading to reduced congestion, secondary incidents, and the associated human and economic losses.

  7. Dry deposition and resuspension of particle-associated metals near a freeway in Los Angeles

    Science.gov (United States)

    Sabin, Lisa D.; Hee Lim, Jeong; Teresa Venezia, Maria; Winer, Arthur M.; Schiff, Kenneth C.; Stolzenbach, Keith D.

    Dry atmospheric deposition represents a potentially large source of pollutant metal contamination in urban stormwater runoff, yet there is a limited amount of research on the relationship between atmospheric emissions and water quality problems in urban areas. In Los Angeles, with air quality that ranks among the worst in the United States, significant quantities of toxic materials are released into the atmosphere every day, and paved road dust represents the largest source of particle-associated metal emissions to the atmosphere. In order to better understand the role of roadways as a source of localized metal deposition, we characterized the horizontal dry deposition patterns of chromium, copper, lead, nickel and zinc upwind and at increasing distances downwind of the I-405 Freeway in coastal Los Angeles. Dry deposition fluxes and atmospheric concentrations of these metals were highest at the site closest to the freeway, and reduced to approximately urban background concentrations between 10 and 150 m downwind of the freeway. Compared with urban background, atmospheric particle size distributions indicated the freeway was a significant source of these metals on large particles >6 μm in diameter, which deposit close to their source and account for the increased dry deposition flux rates observed near the freeway. The spatial pattern of measured deposition flux was well predicted by a relatively simple line-source Gaussian plume model modified to include particle deposition and resuspension. The model results indicated dilution by vertical dispersion of the plume was the most important mechanism regulating downwind concentrations and deposition.

  8. Integrated Variable Speed Limits Control and Ramp Metering for Bottleneck Regions on Freeway

    Directory of Open Access Journals (Sweden)

    Ming-hui Ma

    2015-01-01

    Full Text Available To enhance the efficiency of the existing freeway system and therefore to mitigate traffic congestion and related problems on the freeway mainline lane-drop bottleneck region, the advanced strategy for bottleneck control is essential. This paper proposes a method that integrates variable speed limits and ramp metering for freeway bottleneck region control to relieve the chaos in bottleneck region. To this end, based on the analyses of spatial-temporal patterns of traffic flow, a macroscopic traffic flow model is extended to describe the traffic flow operating characteristic by considering the impacts of variable speed limits in mainstream bottleneck region. In addition, to achieve the goal of balancing the priority of the vehicles on mainline and on-ramp, increasing capacity, and reducing travel delay on bottleneck region, an improved control model, as well as an advanced control strategy that integrates variable speed limits and ramp metering, is developed. The proposed method is tested in simulation for a real freeway infrastructure feed and calibrates real traffic variables. The results demonstrate that the proposed method can substantially improve the traffic flow efficiency of mainline and on-ramp and enhance the quality of traffic flow at the investigated freeway mainline bottleneck.

  9. Relationship between speed and traffic accident and speed limit on freeway

    Institute of Scientific and Technical Information of China (English)

    CHENG Guo-zhu; PEI Yu-long

    2008-01-01

    To develop an equation between discrete degree of speed and traffic accident on freeway in China and give reasonable suggestions of speed management, the relation model was established between speed standard deviation and accident rate per 100,000,000 vehicle kilometers by regression analysis. The model shows that the more discrete is the speed distribution, the higher is the accident rate, which provides theoretical gist for speed limit on freeway. It is suggested that speed limit should be set according to 85th percentile speed obtained by the relationship between 85th percentile speed and Rcc, (curvature change rate of single circular curve), anddifferent speed limits should be set for cars and trucks. Through analyzing spot speed data of eight freeways in China, regression models were established between 85th percentile speed and RCCs and 15th percentile speed and RCCs. Reasonable speed limit suggestion values are put forward through these models.

  10. Variable speed limit strategies’ analysis with cell transmission model on freeway

    Science.gov (United States)

    Li, Shubin; Cao, Danni

    2017-08-01

    Mainline freeway traffic flow control is one of the primary methods of traffic management, which can present the best network situation. In this paper, we integrate variable speed limit (VSL) strategy into the cell transmission model (CTM). Then the implementation of the integrated model on freeway traffic network is discussed. A novel optimal model of controlling freeway traffic flow is proposed for minimizing the total travelling time in the network. A solution algorithm is designed by using a simulation method. Considering the main purpose of the speed limit strategy is to control the mainstream flow, we compare the case where the VSL is used with the one without VSL. A simulation is implemented to show that the control strategy is efficient in describing system’s dynamic performance and the dynamic speed limit strategy significantly alleviates congestion.

  11. Speed Spatial Distribution Models for Traffic Accident Section of Freeway Based on Computer Simulation

    Institute of Scientific and Technical Information of China (English)

    Decai Li; Jiangwei Chu; Wenhui Zhang; Xiaojuan Wang; Guosheng Zhang

    2015-01-01

    Simulation models for accident section on freeway are built in microscopic traffic flow simulation environment. In these models involving 2⁃lane, 3⁃lane and 4⁃lane freeway, one detector is set every 10 m to measure section running speed. According to the simulation results, speed spatial distribution curves for traffic accident section on freeway are drawn which help to determine dangerous sections on upstream of accident section. Furthermore, the speed spatial distribution models are obtained for every speed distribution curve. The results provide theoretical basis for determination on temporal and spatial influence ranges of traffic accident and offer reference to formulation of speed limit scheme and other management measures.

  12. Transmission Lines or Poles, Electric, UtilityCorridor, Published in 2008, Millard County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, was produced all or in part from Other information as of 2008. It is described as 'UtilityCorridor'. Data by...

  13. Roles of a forest corridor between Marojejy, Anjana- haribe-Sud and ...

    African Journals Online (AJOL)

    southwestern part of the provisionally protected rainforest corri- dor between .... The climate in COMATSA is tropical and humid with about ..... Lemurs in a complex landscape: mapping spe- ... Are corridors, fragment size and forest structure.

  14. Traveling waves in an optimal velocity model of freeway traffic

    Science.gov (United States)

    Berg, Peter; Woods, Andrew

    2001-03-01

    Car-following models provide both a tool to describe traffic flow and algorithms for autonomous cruise control systems. Recently developed optimal velocity models contain a relaxation term that assigns a desirable speed to each headway and a response time over which drivers adjust to optimal velocity conditions. These models predict traffic breakdown phenomena analogous to real traffic instabilities. In order to deepen our understanding of these models, in this paper, we examine the transition from a linear stable stream of cars of one headway into a linear stable stream of a second headway. Numerical results of the governing equations identify a range of transition phenomena, including monotonic and oscillating travelling waves and a time- dependent dispersive adjustment wave. However, for certain conditions, we find that the adjustment takes the form of a nonlinear traveling wave from the upstream headway to a third, intermediate headway, followed by either another traveling wave or a dispersive wave further downstream matching the downstream headway. This intermediate value of the headway is selected such that the nonlinear traveling wave is the fastest stable traveling wave which is observed to develop in the numerical calculations. The development of these nonlinear waves, connecting linear stable flows of two different headways, is somewhat reminiscent of stop-start waves in congested flow on freeways. The different types of adjustments are classified in a phase diagram depending on the upstream and downstream headway and the response time of the model. The results have profound consequences for autonomous cruise control systems. For an autocade of both identical and different vehicles, the control system itself may trigger formations of nonlinear, steep wave transitions. Further information is available [Y. Sugiyama, Traffic and Granular Flow (World Scientific, Singapore, 1995), p. 137].

  15. HANFORD SITE RIVER CORRIDOR CLEANUP

    Energy Technology Data Exchange (ETDEWEB)

    BAZZELL, K.D.

    2006-02-01

    In 2005, the US Department of Energy (DOE) launched the third generation of closure contracts, including the River Corridor Closure (RCC) Contract at Hanford. Over the past decade, significant progress has been made on cleaning up the river shore that bordes Hanford. However, the most important cleanup challenges lie ahead. In March 2005, DOE awarded the Hanford River Corridor Closure Contract to Washington Closure Hanford (WCH), a limited liability company owned by Washington Group International, Bechtel National and CH2M HILL. It is a single-purpose company whose goal is to safely and efficiently accelerate cleanup in the 544 km{sup 2} Hanford river corridor and reduce or eliminate future obligations to DOE for maintaining long-term stewardship over the site. The RCC Contract is a cost-plus-incentive-fee closure contract, which incentivizes the contractor to reduce cost and accelerate the schedule. At $1.9 billion and seven years, WCH has accelerated cleaning up Hanford's river corridor significantly compared to the $3.2 billion and 10 years originally estimated by the US Army Corps of Engineers. Predictable funding is one of the key features of the new contract, with funding set by contract at $183 million in fiscal year (FY) 2006 and peaking at $387 million in FY2012. Another feature of the contract allows for Washington Closure to perform up to 40% of the value of the contract and subcontract the balance. One of the major challenges in the next few years will be to identify and qualify sufficient subcontractors to meet the goal.

  16. DEVELOPMENT OF A CRASH RISK PROBABILITY MODEL FOR FREEWAYS BASED ON HAZARD PREDICTION INDEX

    Directory of Open Access Journals (Sweden)

    Md. Mahmud Hasan

    2014-12-01

    Full Text Available This study presents a method for the identification of hazardous situations on the freeways. The hazard identification is done using a crash risk probability model. For this study, about 18 km long section of Eastern Freeway in Melbourne (Australia is selected as a test bed. Two categories of data i.e. traffic and accident record data are used for the analysis and modelling. In developing the crash risk probability model, Hazard Prediction Index is formulated in this study by the differences of traffic parameters with threshold values. Seven different prediction indices are examined and the best one is selected as crash risk probability model based on prediction error minimisation.

  17. Modeling Vehicle Interior Noise Exposure Dose on Freeways Considering Weaving Segment Designs and Engine Operation.

    Science.gov (United States)

    Li, Qing; Qiao, Fengxiang; Yu, Lei; Shi, Junqing

    2017-07-05

    Vehicle interior noise functions at the dominant frequencies of 500 Hz below and around 800 Hz, which fall into the bands that may impair hearing. Recent studies demonstrated that freeway commuters are chronically exposed to vehicle interior noise, bearing the risk of hearing impairment. The interior noise evaluation process is mostly conducted in a lab environment. The test results and the developed noise models may underestimate or ignore the noise effects from dynamic traffic, road conditions and configuration. However, the interior noise is highly associated with vehicle maneuvering. The vehicle maneuvering on a freeway weaving segment is more complex for its nature of conflicting areas. This research is intended to explore the risk of the interior noise exposure on freeway weaving segments for freeway commuters, and improve the interior noise estimation by constructing a decision tree learning based noise exposure dose (NED) model, considering weaving segment designs and engine operation. On-road driving tests were conducted to twelve subjects on State Highway 288 in Houston, Texas. An On-board Diagnosis (OBD) II, a smartphone based roughness app, and a digital sound meter were used to collect vehicle maneuvering and engine information, International Roughness Index, and interior noise levels, respectively. Eleven variables were obtainable from the driving tests, including the length and type of a weaving segment, serving as predictors. The importance of the predictors was estimated by their Out-Of-Bag permuted predictor delta errors. The hazardous exposure level of the interior noise on weaving segments is quantified to Hazard Quotient, NED and daily noise exposure level, respectively. Results showed that the risk of hearing impairment on freeway is acceptable, the interior noise level is the most sensitive to the pavement roughness, and subject to freeway configuration and traffic conditions. The constructed NED model performs highly predictive power (R

  18. Review of heavy metal bio-remediation in contaminated freeway facilitated by adsorption

    Science.gov (United States)

    Zheng, Chaocheng

    2017-08-01

    Toxicity around biological systems is a significant issue for environmental health in a long term. Recent biotechnological approaches for bio-remediation of heavy metals in freeway frequently include mineralization, bio-adsorption or even remediation. Thus, adequate restoration in freeway requiring cooperation, integration and assimilation of such biotechnological advances along with traditional and ethical wisdom to unravel the mystery of nature in the emerging field of bio-remediation was reviewed with highlights to better understand problems associated with toxicity of heavy metals and eco-friendly technologies.

  19. Corridors of time II

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, A.

    2000-07-01

    An eclectic series of essays which, taken together, provide an historical account of the development of the oil sands in Alberta is presented. The story begins with the first realization of the commercial potential of the deposit in the 1880s, and carried forward to the present. The essays describe various aspects of the oil sands saga: the political developments leading to Alberta gaining jurisdiction over the deposit, other events, such as the Canadian Pacific Railway' land grants, and anecdotes about individuals who played a part in the historical evolution of the oil sands industry. Many of the stories come from the author's own experiences which go back some 35 years, when as a neophyte oilman he was involved with what turned out to be the Taber Oil Sands play in southern Alberta. Some of the essays recount experiences of Canadian oilmen abroad; they also describe how these experiences led to accelerated progress in the development of the industry in Canada. The concluding section consists of a series of vignettes about some twenty pioneers of the industry, many of them personally known to the author, whose contributions, small or large, have formed an indispensable part of the fascinating story of the Canadian oil industry in general, and the development of the Alberta oil sands into a world-class source of energy, in particular. tabs., figs. photos.

  20. Predicting which species will benefit from corridors in fragmented landscapes from population growth models.

    Science.gov (United States)

    Hudgens, Brian R; Haddad, Nick M

    2003-05-01

    Connecting isolated patches of habitat in fragmented landscapes with corridors is a popular conservation strategy. This strategy is also controversial in large part because of uncertainty about what characteristics of a species and its environment promote corridor use. In this article we address the question, For what types of species will populations benefit from corridors? We asked this question using a model of two logistically growing populations connected by migration in which both emigration and migration success were determined by the presence or absence of a corridor. We found that in the short run (e.g., during recovery from disaster), corridors are most effective for species with fast-growing populations that have low survivorship when dispersing through unsuitable (matrix) habitat. We also found that emigration rates and habitat-specific mortality rates are key determinants of the effects of corridors on population size. In the long term, corridors are most likely to benefit species with slow-growing populations that have low survivorship when dispersing through matrix habitat. Our results confirm the major conclusions from previous empirical studies of corridor benefits. However, most studies fail to consider the most appropriate questions to determine the potential benefits of habitat corridors. First, what is the time scale of the conservation goal? Corridors have positive effects on different suites of species in the short and long term. Second, is the major threat of local extinction due to sustained population decline or boom-bust cycles? Third, what is the migration rate through the matrix? Fourth, what fraction of migrants dispersing through the matrix successfully immigrate to another patch?

  1. Pedestrian visual recommendation in Kertanegara - Semeru corridor in Malang City

    Science.gov (United States)

    Cosalia, V. B.

    2017-06-01

    Streetscape could be the first impression to see an urban area. One of the streerscape that should be attended to it is corridor of Jl. Kertanegara - Semeru since at that corridor is the road corridor having the strong caracter also as the one of the main axes in Malang city. This research is aim knowing the visual quality also the exact structuring rcommendation for Jl. Kertanegara - Semeru based on pedestrian’s visual. The methode used to this research is Scenic Beauty Estimation (SBE) and used historic study. There is several variables used, they are scale space, visual flexibility, beauty, emphasis, balance and dominant. Based on those variable the pedestrians as a respondent doing the assessment. Based on the result of SBE have been done, it is showed that the visual quality in Corridor Kertanegara Semeru is well enough since the result showed that there are 10 photos in low visual quality in Jl. Semeru and 14 photos in high visual quality in Jl. Kertanegara, Jl. Tugu dan Jl. Kahuripan. By the historic study and based on high visual quality reference doing the structuring recommendation in part of landscape having the low visual quality.

  2. Design of integrated and co-ordinated multimodal transport systems – North Sea – Mediterranean corridor

    Directory of Open Access Journals (Sweden)

    Phil MORTIMER

    2014-10-01

    Full Text Available The paper discusses the North Sea – Mediterranean corridor, part of the Trans-European transport network. A brief discussion on the aspects of multimodality and the possible modes of transport involved in transporting inland freight is presented followed by an introduction to main IT systems that can be implemented to increase the efficiency of freight transport. Presented also is a description on the envisaged investments in freight corridors in Europe. An assessment of information flows is also offered. The study concludes that the concept of a freight corridor should be extended to a network in order for more global benefits to be experienced.

  3. Cumulative Interarrival Time Distributions of Freeway Entrance Ramp Traffic for Traffic Simulations

    Directory of Open Access Journals (Sweden)

    Erdinç Öner

    2013-02-01

    Full Text Available Cumulative interarrival time (IAT distributions for signalized and non-signalized freeway entrance ramps were developed to be used in digital computer traffic simulation models. The data from four different non-signalized entrance ramps (three ramps with a single lane, one ramp with two lanes and two different signalized entrance ramps (both with a single lane were used for developing the cumulative IAT distributions. The cumulative IAT distributions for the signalized and non-signalized entrance ramps were compared with each other and with the cumulative IAT distributions of the lanes for freeways. The comparative results showed that the cumulative IAT distributions for non-signalized entrance ramps are very close to the leftmost lane of a 3-lane freeway where the maximum absolute difference between the cumulative IAT distribution of the leftmost lane of a 3-lane freeway and the entrance ramps cumulative IAT distribution was 3%. The cumulative IAT distribution for the signalized entrance ramps was found to be different from the non-signalized entrance ramp cumulative IAT distribution. The approximated cumulative IAT distributions for signalized and non-signalized entrance ramp traffic for any hourly traffic volume from a few vehicles/hour up to 2,500 vehicles/hour can be obtained at http://www.ohio.edu/orite/research/uitds.cfm.

  4. 78 FR 77550 - Integrated Corridor Management Deployment Planning Grants

    Science.gov (United States)

    2013-12-23

    ... Federal Highway Administration Integrated Corridor Management Deployment Planning Grants AGENCY: Federal... is extending the application period for the Integrated Corridor Management Deployment Planning Grants... Integrated Corridor Management Deployment Planning Grants. The purpose of this notice was to invite States...

  5. The importance and potentials of X corridor in the European traffic system

    Directory of Open Access Journals (Sweden)

    Stojanović Branislav P.

    2004-01-01

    Full Text Available In the network of multimodular corridors, but also in the European traffic system on the whole, corridor X has a very important role more in respect of its position and potentials and less regarding the degree of it valuation. It is particularly so since it represents a section of the intercontinental (land link between Europe and Near and Middle East. At the same time, this corridor is also a dominant axis of development in the majority of SE European countries, as well as a major component of complex spatial-functional transformations that occur within them. That, inter alias, means that the pace of overall development of these parts will depend both on the pace of the overall valuation of potentials this corridors has (and represents, as well as the strengthening of its role as a major element of intra- and inter-regional linking of this part of European continent.

  6. High-Speed Railway Green Corridor Planning: Kunshan Part of Beijing-Shanghai High Speed Railway%高速铁路绿道规划设计探讨——以京沪高速铁路昆山段为例

    Institute of Scientific and Technical Information of China (English)

    苏同向

    2011-01-01

    高铁与其周边环境结合会形成不同的绿地类型.绿道是以自然植被和人工植被为主要存在形态的线状绿地.将高铁景观设计与绿道设计相结合,有助于形成整体性和系统性的高铁沿线景观,更好地维护城市开放空间体系.京沪高铁昆山段景观设计结合绿道概念及理论,从高铁绿道的规模设计、高铁绿道与周边用地空间的关系、高铁绿道设计的人文性等方面出发,充分体现高铁景观设计的地域、文化、生态等多方面的要求,为理解和认识高铁景观提供了一种创新的思维.%Green corridor along high speed rail is special green space. Combining railway landscape with green corridor helps create holistic and systematic railway landscape and better preserve open space. Kunshan part of Beijing-Shanghai high speed rail landscape design follows green corridor concepts, exhibits a new high speed rail landscape in scale, relationship, human care with special vernacular, cultural, and ecological needs.

  7. Long Island Smart Energy Corridor

    Energy Technology Data Exchange (ETDEWEB)

    Mui, Ming [Long Island Power Authority, Uniondale, NY (United States)

    2015-02-04

    The Long Island Power Authority (LIPA) has teamed with Stony Brook University (Stony Brook or SBU) and Farmingdale State College (Farmingdale or FSC), two branches of the State University of New York (SUNY), to create a “Smart Energy Corridor.” The project, located along the Route 110 business corridor on Long Island, New York, demonstrated the integration of a suite of Smart Grid technologies from substations to end-use loads. The Smart Energy Corridor Project included the following key features: -TECHNOLOGY: Demonstrated a full range of smart energy technologies, including substations and distribution feeder automation, fiber and radio communications backbone, advanced metering infrastructure (AM”), meter data management (MDM) system (which LIPA implemented outside of this project), field tools automation, customer-level energy management including automated energy management systems, and integration with distributed generation and plug-in hybrid electric vehicles. -MARKETING: A rigorous market test that identified customer response to an alternative time-of-use pricing plan and varying levels of information and analytical support. -CYBER SECURITY: Tested cyber security vulnerabilities in Smart Grid hardware, network, and application layers. Developed recommendations for policies, procedures, and technical controls to prevent or foil cyber-attacks and to harden the Smart Grid infrastructure. -RELIABILITY: Leveraged new Smart Grid-enabled data to increase system efficiency and reliability. Developed enhanced load forecasting, phase balancing, and voltage control techniques designed to work hand-in-hand with the Smart Grid technologies. -OUTREACH: Implemented public outreach and educational initiatives that were linked directly to the demonstration of Smart Grid technologies, tools, techniques, and system configurations. This included creation of full-scale operating models demonstrating application of Smart Grid technologies in business and residential

  8. Potential negative ecological effects of corridors.

    Science.gov (United States)

    Haddad, Nick M; Brudvig, Lars A; Damschen, Ellen I; Evans, Daniel M; Johnson, Brenda L; Levey, Douglas J; Orrock, John L; Resasco, Julian; Sullivan, Lauren L; Tewksbury, Josh J; Wagner, Stephanie A; Weldon, Aimee J

    2014-10-01

    Despite many studies showing that landscape corridors increase dispersal and species richness for disparate taxa, concerns persist that corridors can have unintended negative effects. In particular, some of the same mechanisms that underlie positive effects of corridors on species of conservation interest may also increase the spread and impact of antagonistic species (e.g., predators and pathogens), foster negative effects of edges, increase invasion by exotic species, increase the spread of unwanted disturbances such as fire, or increase population synchrony and thus reduce persistence. We conducted a literature review and meta-analysis to evaluate the prevalence of each of these negative effects. We found no evidence that corridors increase unwanted disturbance or non-native species invasion; however, these have not been well-studied concerns (1 and 6 studies, respectively). Other effects of corridors were more often studied and yielded inconsistent results; mean effect sizes were indistinguishable from zero. The effect of edges on abundances of target species was as likely to be positive as negative. Corridors were as likely to have no effect on antagonists or population synchrony as they were to increase those negative effects. We found 3 deficiencies in the literature. First, despite studies on how corridors affect predators, there are few studies of related consequences for prey population size and persistence. Second, properly designed studies of negative corridor effects are needed in natural corridors at scales larger than those achievable in experimental systems. Third, studies are needed to test more targeted hypotheses about when corridor-mediated effects on invasive species or disturbance may be negative for species of management concern. Overall, we found no overarching support for concerns that construction and maintenance of habitat corridors may result in unintended negative consequences. Negative edge effects may be mitigated by widening

  9. Simulation of three lanes one-way freeway in low visibility weather by possible traffic accidents

    Science.gov (United States)

    Pang, Ming-bao; Zheng, Sha-sha; Cai, Zhang-hui

    2015-09-01

    The aim of this work is to investigate the traffic impact of low visibility weather on a freeway including the fraction of real vehicle rear-end accidents and road traffic capacity. Based on symmetric two-lane Nagel-Schreckenberg (STNS) model, a cellular automaton model of three-lane freeway mainline with the real occurrence of rear-end accidents in low visibility weather, which considers delayed reaction time and deceleration restriction, was established with access to real-time traffic information of intelligent transportation system (ITS). The characteristics of traffic flow in different visibility weather were discussed via the simulation experiments. The results indicate that incoming flow control (decreasing upstream traffic volume) and inputting variable speed limits (VSL) signal are effective in accident reducing and road actual traffic volume's enhancing. According to different visibility and traffic demand the appropriate control strategies should be adopted in order to not only decrease the probability of vehicle accidents but also avoid congestion.

  10. An extended master-equation approach applied to aggregation in freeway traffic

    Institute of Scientific and Technical Information of China (English)

    Li Jun-Wei; Lin Bo-Liang; Huang Yong-Chang

    2008-01-01

    We restudy the master-equation approach applied to aggregation in a one-dimensional freeway,where the decay transition probabilities for the jump processes are reconstructed based on a car-following model. According to the reconstructed transition probabilities,the clustering behaviours and the stochastic properties of the master equation in a one-lane freeway traffic model are investigated in detail.The numerical results show that the size of the clusters initially below the critical size of the unstable cluster and initially above that of the unstable cluster all enter the same stable state,which also accords with the nucleation theory and is known from the result in earlier work.Moreover,we have obtained more reasonable parameters of the master equation based on some results of cellular automata models.

  11. Development of control strategy of variable speed limits for improving traffic operations at freeway bottlenecks

    Institute of Scientific and Technical Information of China (English)

    李志斌; 刘攀; 王炜; 徐铖铖

    2014-01-01

    A control strategy of variable speed limits (VSL) was developed to reduce the travel time at freeway recurrent bottleneck areas. The proposed control strategy particularly focused on preventing the capacity drop and increasing the discharge flow. A cell transmission model (CTM) was developed to evaluate the effects of the proposed VSL control strategy on the traffic operations. The results show that the total travel time is reduced by 25.5% and the delay is reduced by 56.1%. The average travel speed is increased by 34.3% and the queue length is reduced by 31.0%. The traffic operation is improved by the proposed VSL control strategy. The way to use the proposed VSL control strategy in different types of freeway bottlenecks was also discussed by considering different traffic flow characteristics. It is concluded that the VSL control strategy is effective for merge bottlenecks but is less effective for diverge bottlenecks.

  12. Driver Behavior on Combination of Vertical and Horizontal Curves of Mountainous Freeways

    Directory of Open Access Journals (Sweden)

    Tao Chen

    2014-01-01

    Full Text Available The study of driver behavior is of great importance to the traffic safety of mountainous freeways. In order to study the characteristics of driver behavior on combination of vertical and horizontal curves (CVHCs of mountainous freeways in free flow conditions, designated speed measurement tests of two typical segments of the upgrade direction of Xi’an-Hanzhong freeway were carried out. After data processing, vehicles in free flow were screened out and classified into two groups by K-means clustering method, and then the driver behavior with different lanes, different size vehicles, and different CVHCs was analyzed, respectively. Finally, a vehicle distribution prediction model and a speed prediction model were built which were applied to CVHCs, and a verification test was made to test the accuracy of the models. Research results show that the driver behavior is mainly different among vehicle size, longitudinal slopes, and horizontal curves, and the characteristics of speed control and lane distribution on CVHCs vary according to lanes and combination of road alignment. Also, the prediction results of the models are highly consistent with the measured test results.

  13. Analysis of the Driver’s Behavior Characteristics in Low Volume Freeway Interchange

    Directory of Open Access Journals (Sweden)

    Ronghua Wang

    2016-01-01

    Full Text Available Drivers’ behavior characteristics cannot be ignored in designing freeway interchange facilities in order to improve traffic safety. This paper conducted a field experiment in Qingyin expressway. Four freeway interchanges from K571+538 to K614+932 with relatively low volume were selected, and 12 qualified drivers, 6 car test drivers and 6 truck test drivers, were driving vehicles according to the driving program. GPS and eye-tracking instrument were employed to record running speed, real-time, running track, fixation point, and so forth. Box-plot graphs and Student’s t-test were used to analyze the 12 data sets of driver’s fixation on exit guide signs. Speed-distance curves of effective 11 data sets were plotted to examine the test drivers’ behavior in diverging area and merging area. The results indicated that (1 drivers recognize the exit direction signs in 170 m–180 m advanced distance; (2 the diverging influence area is 1000 m upstream of the diverge point, and the merging influence area is 350 m downstream of the merge point; (3 NO OVERTAKING sign is recommended to be placed at 350 m upstream of the diverge point. The results can provide guidance for the design of freeway interchange facilities and management in order to improve traffic safety.

  14. Model Development for Risk Assessment of Driving on Freeway under Rainy Weather Conditions.

    Directory of Open Access Journals (Sweden)

    Xiaonan Cai

    Full Text Available Rainy weather conditions could result in significantly negative impacts on driving on freeways. However, due to lack of enough historical data and monitoring facilities, many regions are not able to establish reliable risk assessment models to identify such impacts. Given the situation, this paper provides an alternative solution where the procedure of risk assessment is developed based on drivers' subjective questionnaire and its performance is validated by using actual crash data. First, an ordered logit model was developed, based on questionnaire data collected from Freeway G15 in China, to estimate the relationship between drivers' perceived risk and factors, including vehicle type, rain intensity, traffic volume, and location. Then, weighted driving risk for different conditions was obtained by the model, and further divided into four levels of early warning (specified by colors using a rank order cluster analysis. After that, a risk matrix was established to determine which warning color should be disseminated to drivers, given a specific condition. Finally, to validate the proposed procedure, actual crash data from Freeway G15 were compared with the safety prediction based on the risk matrix. The results show that the risk matrix obtained in the study is able to predict driving risk consistent with actual safety implications, under rainy weather conditions.

  15. VT Electric Transmission Line Corridors - substation points

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The ELTRN layer depicts electric transmission line corridors in Vermont. Various methods have been used to digitize features. The data layer...

  16. Regional Ecological Corridors - MLCCS derived 2008

    Data.gov (United States)

    Minnesota Department of Natural Resources — Identification of potential ecological corridors between the MLCCS derived ecological patches (ear_eco08py3). This was generated using cost / distance analysis,...

  17. Mapping mountain torrent hazards in the Hexi Corridor using an evidential reasoning approach

    Science.gov (United States)

    Ran, Youhua; Liu, Jinpeng; Tian, Feng; Wang, Dekai

    2017-02-01

    The Hexi Corridor is an important part of the Silk Road Economic Belt and a crucial channel for westward development in China. Many important national engineering projects pass through the corridor, such as highways, railways, and the West-to-East Gas Pipeline. The frequent torrent disasters greatly impact the security of infrastructure and human safety. In this study, an evidential reasoning approach based on Dempster-Shafer theory is proposed for mapping mountain torrent hazards in the Hexi Corridor. A torrent hazard map for the Hexi Corridor was generated by integrating the driving factors of mountain torrent disasters including precipitation, terrain, flow concentration processes, and the vegetation fraction. The results show that the capability of the proposed method is satisfactory. The torrent hazard map shows that there is high potential torrent hazard in the central and southeastern Hexi Corridor. The results are useful for engineering planning support and resource protection in the Hexi Corridor. Further efforts are discussed for improving torrent hazard mapping and prediction.

  18. The significance of the Danube ecological corridor in the proceedings of implementing ecological networks in Serbia

    Directory of Open Access Journals (Sweden)

    Filipović Dejan

    2015-01-01

    Full Text Available With the modern processes for exploiting land people have altered the original appearance of areas and created cultural environments. The remaining natural environments, whether protected or not, take up a relatively small portion of space and represent isolated islands which in itself can not be sufficient for the preservation of biodiversity or for the fulfillment of national, regional or international goals and commitments related to their preservation. In order to secure the preservation of biodiversity, the strengthening of integrity and the natural processes, such as animal migrations, succession of vegetation and evolution processes, the communication between natural habitats is imperative. Ecological corridors, as integral elements of ecological networks, ensure the preservation of vital ecological interactions by providing a connection between different habitats or areas. Depending on a range of factors, from the fulfillment of demands of different species to the connecting of regions, corridors of local, sub-regional, regional and international importance are identified. The Danube ecological corridor is one of the most significant corridors of international importance which encompasses a large number of habitats which are part of the natural watercourse of the corridor. There are numerous protected areas in the Danube coastal area on Serbia's territory which present themselves as central areas for forming the ecological network, such as: Gornje Podunavlje, Karađorđevo, Fruška Gora, Titelski Breg hill, Kovalski rit marsh, Dunavski loess bluffs, the Sava mouth, Labudovo okno, Deliblato sands, Đerdap and Mala Vrbica. The diverse and mosaic vegetation of the floodplain, as well as the consistency of the protected areas within the Danube corridor have a direct influence on the quality and functionality of this corridor. The goal of this paper is to show the significance of the Danube ecological corridor in the process of implementing

  19. RIVER CORRIDOR BUILDINGS 324 & 327 CLEANUP

    Energy Technology Data Exchange (ETDEWEB)

    BAZZELL, K.D.; SMITH, B.A.

    2006-02-09

    A major challenge in the recently awarded River Corridor Closure (RCC) Contract at the U.S. Department of Energy's (DOE) Hanford Site is decontaminating and demolishing (D&D) facilities in the 300 Area. Located along the banks of the Columbia River about one mile north of Richland, Washington, the 2.5 km{sup 2} (1 mi{sup 2})300 Area comprises only a small part of the 1517 km{sup 2} (586 mi{sup 2}) Hanford Site. However, with more than 300 facilities ranging from clean to highly contaminated, D&D of those facilities represents a major challenge for Washington Closure Hanford (WCH), which manages the new RCC Project for DOE's Richland Operations Office (RL). A complicating factor for this work is the continued use of nearly a dozen facilities by the DOE's Pacific Northwest National Laboratory (PNNL). Most of the buildings will not be released to WCH until at least 2009--four years into the seven-year, $1.9 billion RCC Contract. The challenge will be to deactivate, decommission, decontaminate and demolish (D4) highly contaminated buildings, such as 324 and 327, without interrupting PNNL's operations in adjacent facilities. This paper focuses on the challenges associated with the D4 of the 324 Building and the 327 Building.

  20. China-Pakistan Economic Corridor.

    Energy Technology Data Exchange (ETDEWEB)

    Boyce, Tucker [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-01-01

    International trade and related economic activities in Central and South Asia are increasing as developing economies, particularly India and Pakistan, grow. China continues to emerge as a major regional and global power and has embarked upon numerous regional economic and political initiatives . A major development is the China - Pakistan Economic Corridor (CPEC), a host of infrastructure and trade projects worth over 40 billion American dollars . This report analyzes CPEC a nd its potential regional effects, including the trade security implications of the port and land infrastructure developments . As trade increase s in the reg ion and the major CPEC infrastructure projects are completed, there will be numerous implications on trade security and geopolitics within South Asia. CPEC projects uniquely intersect numerous regional situations, including territorial disputes in Kashmir, the Afghanistan/Pakistan border, and Chinese foreign policy a mbitions. A nuanced understanding of these effects can influence future policy adjustments in this region . The views expressed in this report are those of the author and do not necessarily reflect the position of Sandia National Laboratories or the author's current and past institutions.

  1. Forest edges associated with power-line corridors and implications for corridor siting

    Energy Technology Data Exchange (ETDEWEB)

    Luken, J.O.; Hinton, A.C.; Baker, D.G. (Northern Kentucky Univ., Highland Heights, KY (USA))

    1991-07-01

    In addition to the effects of power-lines on the visual perceptions of urban landscapes, planners and designers need to consider ecological factors and long-term maintenance costs when siting new corridors in forested areas. A survey of 20 corridors in the forests of Northern Kentucky revealed higher mean density and basal area of tree seedlings and saplings in forest edges adjacent to power-line corridors. Some edges also showed distinct community shifts entailing increased importance of shade intolerant tree species. In forests already fragmented by development activities, the presence of a single power-line corridor may render forest patches unsuitable for plant and animal species requiring large forest interior habitats. To avoid this, corridors can be sited in non-forested areas, along existing corridors, along the edges of existing forest patches, or in forest patches that at present lack viable interiors. Applying these recommendations to new corridor projects will stop further forest fragmentation and minimize long-term line maintenance costs, but may also degrade visual perceptions of urban landscapes. Where visual perception is a common facet of land use, corridors may be camouflaged or hidden in forests to reduce visual impact. 5 figs., 2 tabs., 27 refs.

  2. Residential Proximity to Freeways is Associated with Uncontrolled Asthma in Inner-City Hispanic Children and Adolescents

    Directory of Open Access Journals (Sweden)

    Peter Huynh

    2010-01-01

    Full Text Available Background. Proximity to heavy traffic has been linked to increased asthma severity. However, it is unknown whether exposure to heavy traffic is associated with the ability to maintain asthma control. Objectives. This study examines whether exposure to heavy traffic is associated with the ability to maintain asthma control in inner-city children. Methods. 756 inner-city asthmatic Hispanic children were followed for one year in a pediatric asthma management program (Breathmobile. At each scheduled visit, asthma specialist tracked patients' asthma severity and managed their asthma based on the NAEPP guidelines. The patients' residential distance from the nearest freeway was calculated based on residential address at study entry. Distance to nearest freeway was used as a surrogate marker for high exposure from traffic-related air pollutants. Results. Patients who lived near a freeway were significantly more likely to have asthma that was not well controlled (=.03. Patients with intermittent and mild baseline severity have a two-fold increased risk of having asthma that is uncontrolled if they lived <2 miles from a freeway (OR=2.2, =.04. Conclusion. In children with asthma, residential proximity to freeways is associated with uncontrolled asthma.

  3. Large-Scale Habitat Corridors for Biodiversity Conservation: A Forest Corridor in Madagascar.

    Directory of Open Access Journals (Sweden)

    Tanjona Ramiadantsoa

    Full Text Available In biodiversity conservation, habitat corridors are assumed to increase landscape-level connectivity and to enhance the viability of otherwise isolated populations. While the role of corridors is supported by empirical evidence, studies have typically been conducted at small spatial scales. Here, we assess the quality and the functionality of a large 95-km long forest corridor connecting two large national parks (416 and 311 km2 in the southeastern escarpment of Madagascar. We analyze the occurrence of 300 species in 5 taxonomic groups in the parks and in the corridor, and combine high-resolution forest cover data with a simulation model to examine various scenarios of corridor destruction. At present, the corridor contains essentially the same communities as the national parks, reflecting its breadth which on average matches that of the parks. In the simulation model, we consider three types of dispersers: passive dispersers, which settle randomly around the source population; active dispersers, which settle only in favorable habitat; and gap-avoiding active dispersers, which avoid dispersing across non-habitat. Our results suggest that long-distance passive dispersers are most sensitive to ongoing degradation of the corridor, because increasing numbers of propagules are lost outside the forest habitat. For a wide range of dispersal parameters, the national parks are large enough to sustain stable populations until the corridor becomes severely broken, which will happen around 2065 if the current rate of forest loss continues. A significant decrease in gene flow along the corridor is expected after 2040, and this will exacerbate the adverse consequences of isolation. Our results demonstrate that simulation studies assessing the role of habitat corridors should pay close attention to the mode of dispersal and the effects of regional stochasticity.

  4. A biomimetic vision-based hovercraft accounts for bees' complex behaviour in various corridors.

    Science.gov (United States)

    Roubieu, Frédéric L; Serres, Julien R; Colonnier, Fabien; Franceschini, Nicolas; Viollet, Stéphane; Ruffier, Franck

    2014-09-01

    Here we present the first systematic comparison between the visual guidance behaviour of a biomimetic robot and those of honeybees flying in similar environments. We built a miniature hovercraft which can travel safely along corridors with various configurations. For the first time, we implemented on a real physical robot the 'lateral optic flow regulation autopilot', which we previously studied computer simulations. This autopilot inspired by the results of experiments on various species of hymenoptera consists of two intertwined feedback loops, the speed and lateral control loops, each of which has its own optic flow (OF) set-point. A heading-lock system makes the robot move straight ahead as fast as 69 cm s(-1) with a clearance from one wall as small as 31 cm, giving an unusually high translational OF value (125° s(-1)). Our biomimetic robot was found to navigate safely along straight, tapered and bent corridors, and to react appropriately to perturbations such as the lack of texture on one wall, the presence of a tapering or non-stationary section of the corridor and even a sloping terrain equivalent to a wind disturbance. The front end of the visual system consists of only two local motion sensors (LMS), one on each side. This minimalistic visual system measuring the lateral OF suffices to control both the robot's forward speed and its clearance from the walls without ever measuring any speeds or distances. We added two additional LMSs oriented at +/-45° to improve the robot's performances in stiffly tapered corridors. The simple control system accounts for worker bees' ability to navigate safely in six challenging environments: straight corridors, single walls, tapered corridors, straight corridors with part of one wall moving or missing, as well as in the presence of wind.

  5. 78 FR 65751 - Integrated Corridor Management Deployment Planning Grants

    Science.gov (United States)

    2013-11-01

    ... Federal Highway Administration Integrated Corridor Management Deployment Planning Grants AGENCY: Federal... States, Metropolitan Planning Organizations (MPO), and local governments that intend to initiate or continue Integrated Corridor Management (ICM) development with their partners, such as arterial management...

  6. Siliguri: A Geopolitical Manoeuvre Corridor in the Eastern Himalayan Region for China and India

    Directory of Open Access Journals (Sweden)

    Hasan Yaser Malik

    2015-12-01

    Full Text Available Siliguri Corridor being part of Indian West Bengal is a diplomatic manoeuvre place located between Nepal, Bhutan, Bangladesh, India’s Seven Sister States and Chumbi Hills in the Eastern Himalayan Region. Being located at the crossroads and centrally situated between all the neighbouring countries the landlocked Siliguri has an especially economic and political value for the regional countries. The corridor being in close proximity to China and India’s Seven Sister States has added to the diplomatic mosaic of the Eastern Himalayan Region. The region consists of beautiful landscape, mountains and rivers which not only add to topographical diversity but also demographic mixture. Despite its geopolitical significance the area could not advance for not only being a northeastern border region but also for being a gateway to the Seven Sister States. Peripheral development of Siliguri Corridor is one of the reasons for illegal practices like smuggling and terrorism. In year 2002 Nepal, Bhutan and Bangladesh discussed a proposal to form a free trade corridor to simplify the goods transportation through Siliguri Corridor but no such pact could be concluded that would have avoided the activities like smuggling and terrorism mainly through economic and diplomatic ventures.

  7. California air transportation study: A transportation system for the California Corridor of the year 2010

    Science.gov (United States)

    1989-01-01

    To define and solve the problems of transportation in the California Corrider in the year 2010, the 1989 California Polytechnic State University Aeronautical Engineering Senior Design class determined future corridor transportation needs and developed a system to meet the requirements. A market study, which included interpreting travel demand and gauging the future of regional and national air travel in and out of the corridor, allowed the goals of the project to be accurately refined. Comprehensive trade-off studies of several proposed transporation systems were conducted to determine which components would form the final proposed system. Preliminary design and further analysis were performed for each resulting component. The proposed system consists of three vehicles and a special hub or mode mixer, the Corridor Access Port (CAP). The vehicles are: (1) an electric powered aircraft to serve secondary airports and the CAP; (2) a high speed magnetic levitation train running through the CAP and the high population density areas of the corridor; and (3) a vertical takeoff and landing tilt rotor aircraft to serve both intercity and intrametropolitan travelers from the CAP and city vertiports. The CAP is a combination and an extension of the hub, mode mixer, and Wayport concepts. The CAP is an integrated part of the system which meets the travel demands in the corridor, and interfaces with interstate and international travel.

  8. THE ROLE OF THE HYDROLOGICAL FACTOR IN HABITAT DYNAMICS WITHIN THE FLUVIAL CORRIDOR OF DANUBE

    Directory of Open Access Journals (Sweden)

    GH. CLOŢĂ

    2012-03-01

    Full Text Available The role of the hydrological factor in habitat dynamics within the fluvial corridor of Danube. This paper had explored the connections between river hydrology with its changes and habitat dynamics. The fluvial corridor integrates spatially the channel and parts of its floodplain affected by periodical flooding and could be considered as an ecological corridor because of the size of the hydrosystem. The river and its ecosystems depend on geomorphogenetic and biological function and, thus creating a inter-dependence transposed into a concept, namely the fluvial hydrosystem, proposed firstly by Roux 1982, Amoros 1987. The hydrosystem is an ecological complex system constituted of biotopes and specific biocenoses of stream waters, stagnant water bodies, semi-aquatic, terrestrial ecosystems localized in the space of floodplain modeled directly and indirectly by river’s active force.

  9. Analysis of vehicle headway distribution on multi-lane freeway considering car–truck interaction

    Directory of Open Access Journals (Sweden)

    Dewen Kong

    2016-04-01

    Full Text Available The primary objective of this study is to identify the characteristics of vehicle headway on multi-lane freeway under lane management in China considering car–truck interaction. More specifically, the study focused on answering the following two questions: (1 whether the car–truck interaction has impact on headway, that is, headway varies by different leading and following vehicle types and (2 what is the best-fitted distribution model for particular headway type under lane management. The team collected traffic data, including traffic flow rates, percentage of trucks, speeds, headways, and so on from four segments of Shanghai-Nanjing freeway, Jiangsu Province in China. Then, some statistical methods were used to analyze the vehicle headway. It was found that car–car, car/truck, and truck–truck headways are significantly different from each other. Also, the traffic flow rate, percentage of trucks, and lane position were found to have an influence on the vehicle headway through the tests. Using the maximum-likelihood estimation, Kolmogorov–Smirnov test, and chi-square test techniques, the distribution models and parameter functions for each headway type were built and validated. The results showed that lognormal model is suitable for car–car and truck–truck headway types, and inverse Gaussian model fits the car/truck headway type well.

  10. Ultrafine particle size distributions near freeways: Effects of differing wind directions on exposure

    Science.gov (United States)

    Kozawa, Kathleen H.; Winer, Arthur M.; Fruin, Scott A.

    2012-12-01

    High ambient ultrafine particle (UFP) concentrations may play an important role in the adverse health effects associated with living near busy roadways. However, UFP size distributions change rapidly as vehicle emissions dilute and age. These size changes can influence UFP lung deposition rates and dose because deposition in the respiratory system is a strong function of particle size. Few studies to date have measured and characterized changes in near-road UFP size distributions in real-time, thus missing transient variations in size distribution due to short-term fluctuations in wind speed, direction, or particle dynamics. In this study we measured important wind direction effects on near-freeway UFP size distributions and gradients using a mobile platform with 5-s time resolution. Compared to more commonly measured perpendicular (downwind) conditions, parallel wind conditions appeared to promote formation of broader and larger size distributions of roughly one-half the particle concentration. Particles during more parallel wind conditions also changed less in size with downwind distance and the fraction of lung-deposited particle number was calculated to be 15% lower than for downwind conditions, giving a combined decrease of about 60%. In addition, a multivariate analysis of several variables found meteorology, particularly wind direction and temperature, to be important in predicting UFP concentrations within 150 m of a freeway (R2 = 0.46, p = 0.014).

  11. 77 FR 29235 - Patient Protection and Affordable Care Act; Standards Related to Reinsurance, Risk Corridors, and...

    Science.gov (United States)

    2012-05-17

    ... HUMAN SERVICES 45 CFR Part 153 RIN 0938-AR07 Patient Protection and Affordable Care Act; Standards... ] entitled, ``Patient Protection and Affordable Care Act; Standards Related to Reinsurance, Risk Corridors... section 553(b) of the Administrative Procedure Act (APA) (5 U.S.C. 553(b)). However, we can waive...

  12. Developing infrastructure for electric passenger-cars in the corridor between Southern Scandinavia and Germany

    DEFF Research Database (Denmark)

    Guasco, Clement; Jespersen, Per Homann; Lohse, Sandrina

    2012-01-01

    and academic institutions. A strategy for the development of infrastructure for electric passenger-cars in the corridor was formed using the “Future Creating” methodology. The workshop was part of the SCANDRIA Action Programme and pointed towards ways for e-mobility in the region. The workshop also provided...

  13. NOx emissions from Euro IV busses with SCR systems associated with urban, suburban and freeway driving patterns.

    Science.gov (United States)

    Fu, Mingliang; Ge, Yunshan; Wang, Xin; Tan, Jianwei; Yu, Linxiao; Liang, Bin

    2013-05-01

    NOx and particulate matter (PM) emissions from heavy-duty diesel vehicles (HDVs) have become the most important sources of pollutants affecting urban air quality in China. In recent years, a series of emission control strategies and diesel engine polices have been introduced that require advanced emission control technology. China and Europe mostly have used Selective Catalytic Reduction (SCR) with urea to meet the Euro IV diesel engine emission standard. In this study, two Euro IV busses with SCR were tested by using potable emission measurement system (PEMS) to assess NOx emissions associated with urban, suburban and freeway driving patterns. The results indicated that with the SCR system, the urea injection time for the entire driving period increased with higher vehicle speed. For freeway driving, the urea injection time covered 71%-83% of the driving period; the NOx emission factors from freeway driving were lower than those associated with urban and suburban driving. Unfortunately, the NOx emission factors were 2.6-2.8-, 2.3-2.7- and 2.2-2.3-fold higher than the Euro IV standard limits for urban, suburban and freeway driving, respectively; NOx emission factors (in g/km and g/(kW·h)) from the original vehicles (without SCR) were higher than their corresponding vehicles with SCR for suburban and freeway driving. Compared with the IVE model results, the measured NOx emission factors were 1.60-1.16-, 1.77-1.27-, 2.49-2.44-fold higher than the NOx predicted by the IVE model for urban and suburban driving, respectively. Thus, an adjustment of emission factors is needed to improve the estimation of Euro IV vehicle emissions in China.

  14. Corridors of trade and power

    DEFF Research Database (Denmark)

    Hagmann, Tobias; Stepputat, Finn

    Despite ongoing conflicts, Somalia’s economy has evolved considerably since the disintegration of the central state in 1991. However, our knowledge and understanding of how transnational Somali economic life is organised and how it influences political dynamics remains limited. As part of the res......Despite ongoing conflicts, Somalia’s economy has evolved considerably since the disintegration of the central state in 1991. However, our knowledge and understanding of how transnational Somali economic life is organised and how it influences political dynamics remains limited. As part...

  15. Towards reducing traffic congestion using cooperative adaptive cruise control on a freeway with a ramp

    Directory of Open Access Journals (Sweden)

    Georges Arnaout

    2011-12-01

    Full Text Available Purpose: In this paper, the impact of Cooperative Adaptive Cruise Control (CACC systems on traffic performance is examined using microscopic agent-based simulation. Using a developed traffic simulation model of a freeway with an on-ramp - created to induce perturbations and to trigger stop-and-go traffic, the CACC system’s effect on the traffic performance is studied. The previously proposed traffic simulation model is extended and validated. By embedding CACC vehicles in different penetration levels, the results show significance and indicate the potential of CACC systems to improve traffic characteristics and therefore can be used to reduce traffic congestion. The study shows that the impact of CACC is positive but is highly dependent on the CACC market penetration. The flow rate of the traffic using CACC is proportional to the market penetration rate of CACC equipped vehicles and the density of the traffic.Design/methodology/approach: This paper uses microscopic simulation experiments followed by a quantitative statistical analysis. Simulation enables researchers manipulating the system variables to straightforwardly predict the outcome on the overall system, giving researchers the unique opportunity to interfere and make improvements to performance. Thus with simulation, changes to variables that might require excessive time, or be unfeasible to carry on real systems, are often completed within seconds.Findings: The findings of this paper are summarized as follow:•\tProvide and validate a platform (agent-based microscopic traffic simulator in which any CACC algorithm (current or future may be evaluated.•\tProvide detailed analysis associated with implementation of CACC vehicles on freeways.•\tInvestigate whether embedding CACC vehicles on freeways has a significant positive impact or not.Research limitations/implications: The main limitation of this research is that it has been conducted solely in a computer laboratory. Laboratory

  16. 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.

  17. Radius model of convex vertical curve of freeway based on attachment coefficient

    Institute of Scientific and Technical Information of China (English)

    LI Song-ling; PEI Yu-long

    2008-01-01

    A longitudinal slope brake model was established for the radius calculation of vertical curve of free-way through analyzing the dynamics of brake-running of vehicles running on the longitudinal slope road section. To satisfy the requirement of sight distance, a relation model was established for the attachment coefficient and the convex vertical curve radius. Using MATLAB simulation technique, the convex vertical curve radius at different attachment conditions was calculated accurately and a three-dimensional figure was drawn to describe the relation between the adhesive coefficient, the driving velocity and the radius of vertical curve. The correlation between the convex vertical curve radius and the adhesive coefficient was further analyzed and compared with National Technical Standards. The suggested radius of vertical curve was then put forward to provide a theoretical platform for the security design of the convex vertical curve.

  18. Corridors promote fire via connectivity and edge effects.

    Science.gov (United States)

    Brudvig, Lars A; Wagner, Stephanie A; Damschen, Ellen I

    2012-04-01

    Landscape corridors, strips of habitat that connect otherwise isolated habitat patches, are commonly employed during management of fragmented landscapes. To date, most reported effects of corridors have been positive; however, there are long-standing concerns that corridors may have unintended consequences. Here, we address concerns over whether corridors promote propagation of disturbances such as fire. We collected data during prescribed fires in the world's largest and best replicated corridor experiment (Savannah River Site, South Carolina, USA), six -50-ha landscapes of open (shrubby/herbaceous) habitat within a pine plantation matrix, to test several mechanisms for how corridors might influence fire. Corridors altered patterns of fire temperature through a direct connectivity effect and an indirect edge effect. The connectivity effect was independent of fuel levels and was consistent with a hypothesized wind-driven "bellows effect." Edges, a consequence of corridor implementation, elevated leaf litter (fuel) input from matrix pine trees, which in turn increased fire temperatures. We found no evidence for corridors or edges impacting patterns of fire spread: plots across all landscape positions burned with similar probability. Impacts of edges and connectivity on fire temperature led to changes in vegetation: hotter-burning plots supported higher bunch grass cover during the field season after burning, suggesting implications for woody/herbaceous species coexistence. To our knowledge, this represents the first experimental evidence that corridors can modify landscape-scale patterns of fire intensity. Corridor impacts on fire should be carefully considered during landscape management, both in the context of how corridors connect or break distributions of fuels and the desired role of fire as a disturbance, which may range from a management tool to an agent to be suppressed. In our focal ecosystem, longleaf pine woodland, corridors might provide a previously

  19. Corridors of trade and power

    DEFF Research Database (Denmark)

    Hagmann, Tobias; Stepputat, Finn

    Despite ongoing conflicts, Somalia’s economy has evolved considerably since the disintegration of the central state in 1991. However, our knowledge and understanding of how transnational Somali economic life is organised and how it influences political dynamics remains limited. As part of the res......Despite ongoing conflicts, Somalia’s economy has evolved considerably since the disintegration of the central state in 1991. However, our knowledge and understanding of how transnational Somali economic life is organised and how it influences political dynamics remains limited. As part...... of the research programme “Governing Economic Hubs and Flows in Somali East Africa” (GOVSEA) this working paper provides an overview of the existing literature on the subject. This paper presents a summary analysis of key features of the Somali economy and proposes a periodisation of the evolution of Somali...... business between 1991 and today: from the heavily informalised economy of the 1980s, the violent markets of the early 1990s and the subsequent ‘duty-free shop’ period, to the emergence of a more regulated economy with a significant development of multi-clan shareholder companies since the mid-2000s...

  20. The role of the free-way space in the generation of muscle pain among denture-wearers.

    Science.gov (United States)

    Monteith, B

    1984-09-01

    Although the myofascial pain dysfunction syndrome has a multiple aetiology, faulty vertical dimension is a frequent cause of muscular pain among wearers of full dentures. Furthermore, it has been found that the restoration of a physiological free-way space in such cases, using a method which is based upon cephalometric analysis of the gonial angle, often leads to a dramatic remission of pain. The present investigation was prompted by curiosity as to what the underlying algogenic mechanisms in these cases might be; and how a change in the vertical dimension should so modify them as to result in the disappearance of the pain symptoms. The study is necessarily of a speculative nature, and makes use of two representative cases, one of which was adjudged to have too little free-way, and the other too much. Principles of neuromuscular physiology are applied in attempting to explain the clinical phenomena involved, as well as to find a reason for certain electro-myographic artefacts noted in one of the cases, which would appear to call into question the notion that muscular hyperactivity, per se, is responsible for muscular pain. Potgieter, Monteith & Kemp (1983) have presented an hypothesis that the amount of free-way space present in an individual is an expression of the contractile power of the masseter and medial pterygoid muscles. They have also devised a method whereby, through cephalometric analysis, the optimal amount of free-way may be determined for an edentulous patient during denture construction. Furthermore, they have stated that their method has proved particularly effective in the treatment of denture-wearers presenting with symptoms of the myofascial pain dysfunction syndrome. However, in the light of this syndrome's multifactorial aetiology one must assume that only those symptoms which are related to a faulty free-way space are at issue. The purpose of the present investigation is to examine the latter assertion; and by the application of the suggested

  1. Changes in air quality at near-roadway schools after a major freeway expansion in Las Vegas, Nevada.

    Science.gov (United States)

    Brown, Steven G; McCarthy, Michael C; DeWinter, Jennifer L; Vaughn, David L; Roberts, Paul T

    2014-09-01

    Near-roadway ambient black carbon (BC) and carbon monoxide (CO) concentrations were measured at two schools adjacent to a freeway and at an urban background school 2 km from the freeway to determine the change in concentrations attributable to vehicle emissions after the three-lane expansion of U.S. Highway 95 (US 95) in Las Vegas, Nevada. Between summer 2007 and summer 2008, average weekday small-vehicle volume increased by 40% +/- 2% (standard error). Average weekday large-vehicle volume decreased by 17% +/- 5%, due to a downturn in the economy and an associated decline in goods movement. Average vehicle speed increased from 58 to 69 mph, a 16% +/- 1% increase. The authors compared BC and CO concentrations in summer 2007 with those in summer 2008 to understand what effect the expansion of the freeway may have had on ambient concentrations: BC and CO were measured 17 m north of the freeway sound wall, CO was measured 20 m south of the sound wall, and BC was measured at an urban background site 2 km south of the freeway. Between summer 2007 and summer 2008, median BC decreased at the near-road site by 40% +/- 2% and also decreased at the urban background site by 24% +/- 4%, suggesting that much of the change was due to decreases in emissions throughout Las Vegas, rather than only on US 95. CO concentrations decreased by 14% +/- 2% and 10% +/- 3% at the two near-road sites. The decrease in BC concentrations after the expansion is likely due to the decrease in medium- and heavy-duty-vehicle traffic resulting from the economic recession. The decrease in CO concentrations may be a result of improved traffic flow, despite the increase in light-duty-vehicle traffic. Implications: Monitoring of BC and CO at near-road locations in Las Vegas demonstrated the impacts of changes in traffic volume and vehicle speed on near-road concentrations. However, urban-scale declines in concentrations were larger than near-road changes due to the impacts of the economic recession that

  2. Complexity Analysis of Traffic in Corridors-in-the-Sky

    Science.gov (United States)

    Xue, Min; Zelinski, Shannon Jean

    2010-01-01

    The corridors-in-the-sky concept imitates the highway system in ground transportation. The benefit expected from a corridor relies on its capability of handling high density traffic with negligible controller workload, the acceptance of extra fuel or distance, and the complexity reduction in underlying sectors. This work evaluates a selected corridor from these perspectives through simulations. To examine traffic inside the corridor, a corridor traffic simulation tool that can resolve conflicts is developed using C language. Prescribed conflict resolution maneuvers mimic corridor users behaviors and conflict resolution counts measure complexity. Different lane options and operational policies are proposed to examine their impacts on complexity. Fuel consumption is calculated and compared for corridor traffic. On the other hand, to investigate the complexity of non-corridor traffic in underlying sectors, the existing Airspace Concept Evaluation System tool is utilized along with the Automated Airspace Concept tool. The number of conflict resolutions is examined and treated as the complexity measurement. The results show heavy traffic can be managed with low complexity for a historical traffic schedule simulated with appropriate operational policies and lane options. For instance, with 608 flights and peak aircraft count of 100, only 84 actions need to be taken in a 24-hour period to resolve the conflicts for an 8-lane corridor. Compared with the fuel consumptions with great circle trajectories, the simulation of corridor traffic shows that the total extra fuel for corridor flights is 26,373 gallons, or 2.76%, which is 0.38% less than flying filed flight plans. Without taking climb and descent portions of corridor traffic, the complexity of underlying sectors is reduced by 17.71%. However the climb and descent portions will eliminate the reduction and the overall complexity of sectors is actually increased by 9.14%.

  3. KPI Building Blocks For Successful Green Transport Corridor Implementation

    Directory of Open Access Journals (Sweden)

    Prause Gunnar

    2015-12-01

    Full Text Available The green transport corridor concept represents a cornerstone in the development of integrated and sustainable transport solutions. Important properties of green corridors are their transnational character and their high involvement of large numbers of public and private stakeholders, including political level, requiring sophisticated approaches for implementation, management and governance. The current scientific discussion focusses on Key Performance Indicators (KPI for monitoring and management of green transport corridor performance emphasizing the operational aspects.

  4. A Data-Driven Control Design Approach for Freeway Traffic Ramp Metering with Virtual Reference Feedback Tuning

    Directory of Open Access Journals (Sweden)

    Shangtai Jin

    2014-01-01

    Full Text Available ALINEA is a simple, efficient, and easily implemented ramp metering strategy. Virtual reference feedback tuning (VRFT is most suitable for many practical systems since it is a “one-shot” data-driven control design methodology. This paper presents an application of VRFT to a ramp metering problem of freeway traffic system. When there is not enough prior knowledge of the controlled system to select a proper parameter of ALINEA, the VRFT approach is used to optimize the ALINEA's parameter by only using a batch of input and output data collected from the freeway traffic system. The extensive simulations are built on both the macroscopic MATLAB platform and the microscopic PARAMICS platform to show the effectiveness and applicability of the proposed data-driven controller tuning approach.

  5. Effects of vegetation, corridor width and regional land use on early successional birds on powerline corridors.

    Directory of Open Access Journals (Sweden)

    Robert A Askins

    Full Text Available Powerline rights-of-way (ROWs often provide habitat for early successional bird species that have suffered long-term population declines in eastern North America. To determine how the abundance of shrubland birds varies with habitat within ROW corridors and with land use patterns surrounding corridors, we ran Poisson regression models on data from 93 plots on ROWs and compared regression coefficients. We also determined nest success rates on a 1-km stretch of ROW. Seven species of shrubland birds were common in powerline corridors. However, the nest success rates for prairie warbler (Dendroica discolor and field sparrow (Spizella pusilla were <21%, which is too low to compensate for estimated annual mortality. Some shrubland bird species were more abundant on narrower ROWs or at sites with lower vegetation or particular types of vegetation, indicating that vegetation management could be refined to favor species of high conservation priority. Also, several species were more abundant in ROWs traversing unfragmented forest than those near residential areas or farmland, indicating that corridors in heavily forested regions may provide better habitat for these species. In the area where we monitored nests, brood parasitism by brown-headed cowbirds (Molothrus ater occurred more frequently close to a residential area. Although ROWs support dense populations of shrubland birds, those in more heavily developed landscapes may constitute sink habitat. ROWs in extensive forests may contribute more to sustaining populations of early successional birds, and thus may be the best targets for habitat management.

  6. Maputo development corridor: Evaluation of first phase

    CSIR Research Space (South Africa)

    Schutte, IC

    2005-07-01

    Full Text Available undertaken within the southern African region since 1995, following the peace agreement in Mozambique and the first non-racial elections in South Africa in 1994. Coming at a time of substantial political change and growing co-operation within the region... and proximity to the corridor. As regards the Mozambican section of the MDC, the 1996/97 official unemployment rate (formal wage-earning employment) was estimated at around 69 per cent. This figure is almost equivalent to the total number of people added...

  7. Evaluating landscape options for corridor restoration between giant panda reserves.

    Directory of Open Access Journals (Sweden)

    Fang Wang

    Full Text Available The establishment of corridors can offset the negative effects of habitat fragmentation by connecting isolated habitat patches. However, the practical value of corridor planning is minimal if corridor identification is not based on reliable quantitative information about species-environment relationships. An example of this need for quantitative information is planning for giant panda conservation. Although the species has been the focus of intense conservation efforts for decades, most corridor projects remain hypothetical due to the lack of reliable quantitative researches at an appropriate spatial scale. In this paper, we evaluated a framework for giant panda forest corridor planning. We linked our field survey data with satellite imagery, and conducted species occupancy modelling to examine the habitat use of giant panda within the potential corridor area. We then conducted least-cost and circuit models to identify potential paths of dispersal across the landscape, and compared the predicted cost under current conditions and alternative conservation management options considered during corridor planning. We found that due to giant panda's association with areas of low elevation and flat terrain, human infrastructures in the same area have resulted in corridor fragmentation. We then identified areas with high potential to function as movement corridors, and our analysis of alternative conservation scenarios showed that both forest/bamboo restoration and automobile tunnel construction would significantly improve the effectiveness of corridor, while residence relocation would not significantly improve corridor effectiveness in comparison with the current condition. The framework has general value in any conservation activities that anticipate improving habitat connectivity in human modified landscapes. Specifically, our study suggested that, in this landscape, automobile tunnels are the best means to remove current barriers to giant panda

  8. Evaluating landscape options for corridor restoration between giant panda reserves.

    Science.gov (United States)

    Wang, Fang; McShea, William J; Wang, Dajun; Li, Sheng; Zhao, Qing; Wang, Hao; Lu, Zhi

    2014-01-01

    The establishment of corridors can offset the negative effects of habitat fragmentation by connecting isolated habitat patches. However, the practical value of corridor planning is minimal if corridor identification is not based on reliable quantitative information about species-environment relationships. An example of this need for quantitative information is planning for giant panda conservation. Although the species has been the focus of intense conservation efforts for decades, most corridor projects remain hypothetical due to the lack of reliable quantitative researches at an appropriate spatial scale. In this paper, we evaluated a framework for giant panda forest corridor planning. We linked our field survey data with satellite imagery, and conducted species occupancy modelling to examine the habitat use of giant panda within the potential corridor area. We then conducted least-cost and circuit models to identify potential paths of dispersal across the landscape, and compared the predicted cost under current conditions and alternative conservation management options considered during corridor planning. We found that due to giant panda's association with areas of low elevation and flat terrain, human infrastructures in the same area have resulted in corridor fragmentation. We then identified areas with high potential to function as movement corridors, and our analysis of alternative conservation scenarios showed that both forest/bamboo restoration and automobile tunnel construction would significantly improve the effectiveness of corridor, while residence relocation would not significantly improve corridor effectiveness in comparison with the current condition. The framework has general value in any conservation activities that anticipate improving habitat connectivity in human modified landscapes. Specifically, our study suggested that, in this landscape, automobile tunnels are the best means to remove current barriers to giant panda movements caused by

  9. Predicting crash likelihood and severity on freeways with real-time loop detector data.

    Science.gov (United States)

    Xu, Chengcheng; Tarko, Andrew P; Wang, Wei; Liu, Pan

    2013-08-01

    Real-time crash risk prediction using traffic data collected from loop detector stations is useful in dynamic safety management systems aimed at improving traffic safety through application of proactive safety countermeasures. The major drawback of most of the existing studies is that they focus on the crash risk without consideration of crash severity. This paper presents an effort to develop a model that predicts the crash likelihood at different levels of severity with a particular focus on severe crashes. The crash data and traffic data used in this study were collected on the I-880 freeway in California, United States. This study considers three levels of crash severity: fatal/incapacitating injury crashes (KA), non-incapacitating/possible injury crashes (BC), and property-damage-only crashes (PDO). The sequential logit model was used to link the likelihood of crash occurrences at different severity levels to various traffic flow characteristics derived from detector data. The elasticity analysis was conducted to evaluate the effect of the traffic flow variables on the likelihood of crash and its severity.The results show that the traffic flow characteristics contributing to crash likelihood were quite different at different levels of severity. The PDO crashes were more likely to occur under congested traffic flow conditions with highly variable speed and frequent lane changes, while the KA and BC crashes were more likely to occur under less congested traffic flow conditions. High speed, coupled with a large speed difference between adjacent lanes under uncongested traffic conditions, was found to increase the likelihood of severe crashes (KA). This study applied the 20-fold cross-validation method to estimate the prediction performance of the developed models. The validation results show that the model's crash prediction performance at each severity level was satisfactory. The findings of this study can be used to predict the probabilities of crash at

  10. Attractive Mobile Corridors - The Power of Light Rail Infrastructures

    DEFF Research Database (Denmark)

    Olesen, Mette; Lassen, Claus

    2013-01-01

    Light rail is a popular tool in urban development strategies in many European cities. One argument for choosing a rail-based solution is that it signals stability to investors and will attract development and investments in the corridor. The choice of corridor in the various light rail cities...

  11. Planning of transport corridors by use of GIS

    DEFF Research Database (Denmark)

    Kronbak, Jacob; Moshøj, Claus Rehfeld; Grevy, Bo

    1998-01-01

    The paper adresses principles for the application of geographical information systems (GIS) as a tool in the planning of transport corridors. Specifically, the paper describes the COPE (corridor planning and evaluation) model that has been developed within the EU 4th FP Strategic Transport projects...

  12. Variable input parameter influence on river corridor prediction

    NARCIS (Netherlands)

    Zerfu, T.; Beevers, L.; Crosato, A.; Wright, N.

    2015-01-01

    This paper considers the erodible river corridor, which is the area in which the main river channel is free to migrate over a period of time. Due to growing anthropogenic pressure, predicting the corridor width has become increasingly important for the planning of development along rivers. Several a

  13. HISTORICAL DESERTIFICATION PROCESS IN HEXI CORRIDOR, CHINA

    Institute of Scientific and Technical Information of China (English)

    WANG Nai-ang; ZHANG Chun-hui; LI Gang; CHENG Hong-yi

    2005-01-01

    Over the last 2000 years, approximately 38 ancient cities were abandoned through desertification in Hexi Corridor, Northwest China. Among them, 21.05% were abandonedduring the Northern and Southern Dynasties, 21.05% during the end of the Tang Dynasty andthe Five Dynasties, and 57.9% during the Ming and Qing dynas ties. At the same time, main lakes were shrinking rapidly from the 5th Century to the 6th Century and the end of the Qing Dynasty. The climate in these periods was relatively arid and cold with frequent dusts. The phase of these changes indicated that there were three periods of desertification enlargement in the northern China. They were Northern and Southern Dynasties, the end of Tang Dynasty and Five Dynasties, the Ming and Qing dynasties. The macro-process of desertification in the study area was controlled mainly by the climatic changes. But from the facts that the population density in the middle of Qing Dynasty had exceeded the critical index of population pressure in arid area and the usage rate of water resources had exceeded 40% in Hexi Corridor, this paper also suggests that human activities have played an important role in desertification processes of the study area mainly during the recent 300 years.

  14. How to measure capabilities within corridors?

    Directory of Open Access Journals (Sweden)

    Thomas MACOUN

    2011-01-01

    Full Text Available Traditional methods of measuring the capacities of infrastructures are usually based on indicators like passenger car units (PCU. It is quite clear that these methods of capacity evaluation (categories of roads, calculation procedures, capacity limits, e.g. defined in the HCM – Highway Capacity Manual cannot be used to picture the intermodality of the traffic system. The first step has to include the intermodality (modal split in the cross section of a road (pedestrians, bicycles, public transport, private vehicles, and in a further step it is necessary to account for all alternatives within the corridor, like parallel routed railways or public transport lines, to reach an intermodal point of view. Finally it is also necessary to include the effects on the settlement structure. Beside intermodality, any new method also has to consider cost effectiveness, a comprehensive consideration of feedbacks in the traffic system, as well as compatibility to CBA. As a result it is necessary to find new indicators (instead of car units to define passenger and freight flows. There are guidelines in progress auditing transport operations and infrastructure conditions of roadways. A revision of these guidelines aims to integrate different modes of transport by changing the key-indicators (e.g. incline, curviness, roadway width, capacity utilisation and to use a system approach which includes indicators like modal split, car occupancy or utilised capacity of lorries. The procedure presented in this paper can be seen as one building block to meet the demands of future assessments within corridors.

  15. Codornices Creek Corridor: Land Use Regulation, Creek Restoration, and their Impacts on the Residents’ Perceptions

    OpenAIRE

    Stokenberga, Aiga; Sen, Arijit

    2013-01-01

    The Codornices Creek, an ecological corridor located in the northern part of Berkeley, California, is among the most visible, publicly accessible, and socio-economically diverse creeks in the East Bay. The current study examinesthe comparative influence of individual-level socio-economic conditions, involvementin Creek restoration activities, and the existing Creek-related land useregulations on the area residents’ sense of community and perception of areaecology. Based on the data collected ...

  16. An experimental test of whether habitat corridors affect pollen transfer.

    Energy Technology Data Exchange (ETDEWEB)

    Townsend, Patricia A.; Levey, Douglas J.

    2005-02-01

    Abstract. Negative effects of habitat fragmentation are thought to be diminished when habitat patches are joined by a corridor. A key assumption is that corridors facilitate exchange rates of organisms between otherwise isolated patches. If the organisms are pollinators, corridors may be important for maintaining genetically viable populations of the plants that they pollinate. We tested the hypothesis that corridors increase the movement of insect pollinators into patches of habitat and thereby increase pollen transfer for two species of plants, one pollinated by butterflies (Lantana camara) and the other by bees and wasps (Rudbeckia hirta). We worked in an experimental landscape consisting of 40 greater than or equal to 1-ha patches of early-successional habitat in a matrix of forest. Within each of eight experimental units, two patches were connected by a corridor (150 X 25 m), and three were not. Patch shape varied to control for the area added by the presence of a corridor. Differences in patch shape also allowed us to test alternative hypotheses of how corridors might function. The Traditional Corridor Hypothesis posits that corridors increase immigration and emigration by functioning as movement conduits between patches. The Drift Fence Hypothesis posits that corridors function by ‘‘capturing’’ organisms dispersing through the matrix, redirecting them into associated habitat patches. Using fluorescent powder to track pollen, we found that pollen transfer by butterflies between patches connected by a corridor was significantly higher than between unconnected patches (all values mean plus or minus 1 SE: 59% plus or minus 9.2% vs. 25% plus or minus 5.2% of flowers receiving pollen). Likewise, pollen transfer by bees and wasps was significantly higher between connected patches than between unconnected patches (30% plus or minus 4.2% vs. 14.5% plus or minus 2.2%). These results support the Traditional Corridor Hypothesis. There was little support, however

  17. The actual relevance of ecological corridors in nature conservation

    Directory of Open Access Journals (Sweden)

    Ćurčić Nina B.

    2013-01-01

    Full Text Available The paper considers theoretical and applied foundations of the concept of the ecological corridors in nature conservation. Their relevance comes from recent ecological phenomenon of habitat fragmentation which is rapidly increasing during last decades. Habitat fragmentation is one of the main threats to richness and diversity of wildlife. Ecological corridors can mitigate the loss and fragmentation of habitat. Corridors perform as “bridges” between habitats for species and they provide a flow of the natural or even anthropogenic caused disturbances. In this paper we will present the meaning and significance of ecological corridors in nature conservation, as well as types of ecological corridors and their ecological benefits. Methodological and practical approaches in nature protection system in Serbia are included. [Projekat Ministarstva nauke Republike Srbije, br. 47007 i br. 176008

  18. Integrated HS and ALS Remote Sensing Data Sources to Develop Green Corridors in Sopron Mountains

    Directory of Open Access Journals (Sweden)

    János Tamás

    2015-01-01

    Full Text Available The green corridors are part of the European Union rural landscapes, but the regional increase in size of agricultural parcels had a significant effect on European land use in the 20th century. This effect radically reduced the coverage of natural forest. One ecological problem with the remaining forests is the partial missing of the network connecting the parts with ecological green corridors. Another economical problem is the verifiability for the payment system of agroforestry. Remote sensing methods are currently used to supervise monitoring the arable lands, plantations, natural reserve areas, as well as to help for the European Union payment system. Nowadays the airborne hyperspectral (HS and LiDAR (Light Detection And Ranging; ALS remote sensing technologies are becoming of more widespread use. They can be applied especially in spatial decision support system (SDSS, used in decisions about for nature, environment, forests, agriculture protection, conservation and monitoring, as well as for monitoring of biomass production. Our site selection model was the first step towards planning an agroforestry plantation which uses these integrated technologies to connect the parts with green corridors.

  19. Freeway Multisensor Data Fusion Approach Integrating Data from Cellphone Probes and Fixed Sensors

    Directory of Open Access Journals (Sweden)

    Shanglu He

    2016-01-01

    Full Text Available Freeway traffic state information from multiple sources provides sufficient support to the traffic surveillance but also brings challenges. This paper made an investigation into the fusion of a new data combination from cellular handoff probe system and microwave sensors. And a fusion method based on the neural network technique was proposed. To identify the factors influencing the accuracy of fusion results, we analyzed the sensitivity of those factors by changing the inputs of neural-network-based fusion model. The results showed that handoff link length and sample size were identified as the most influential parameters to the precision of fusion. Then, the effectiveness and capability of proposed fusion method under various traffic conditions were evaluated. And a comparative analysis between the proposed method and other fusion approaches was conducted. The results of simulation test and evaluation showed that the fusion method could complement the drawback of each collection method, improve the overall estimation accuracy, adapt to the variable traffic condition (free flow or incident state, suit the fusion of data from cellphone probes and fixed sensors, and outperform other fusion methods.

  20. Participatory Democracy, Community Organizing and the Community Assessment of Freeway Exposure and Health (CAFEH) Partnership

    Science.gov (United States)

    Sprague Martinez, Linda; Reisner, Ellin; Campbell, Maria; Brugge, Doug

    2017-01-01

    Background: Conflicting interests, power imbalance and relationships characterized by distrust are just a few of the many challenges community–academic research partnerships face. In addition, the time it takes to build relationships is often overlooked, which further complicates matters and can leave well-intentioned individuals re-creating oppressive conditions through inauthentic partnerships. This paper presents a novel approach of using meeting minutes to explore partnership dynamics. The Community Assessment of Freeway Exposure and Health (CAFEH) partnership is used as an illustrative case study to identify how community academic partnerships overcome the challenges associated with community-based participatory research (CBPR). CAFEH is a study of ultrafine particle exposure (UFP) near highways in the Boston, MA area. Methods: Qualitative analysis was applied to meeting minutes and process evaluation reports from the first three years of the CAFEH study (n = 73 files). In addition, a group meeting was held with project partners in order to contextualize the findings from the document analysis. Results: The three most commonly referenced challenges included language barriers, the overall project structure and budgetary constraints. Meanwhile, a heavy emphasis on process and an approach steeped in participatory democracy facilitated CAFEH’s ability to overcome these challenges, as well as sustain and augment strong partnership ties. Conclusions: This experience suggests that leadership that incorporates an organizing approach and a transformational style facilitates CBPR processes and helps teams surmount challenges. PMID:28165418

  1. Predicting Freeway Work Zone Delays and Costs with a Hybrid Machine-Learning Model

    Directory of Open Access Journals (Sweden)

    Bo Du

    2017-01-01

    Full Text Available A hybrid machine-learning model, integrating an artificial neural network (ANN and a support vector machine (SVM model, is developed to predict spatiotemporal delays, subject to road geometry, number of lane closures, and work zone duration in different periods of a day and in the days of a week. The model is very user friendly, allowing the least inputs from the users. With that the delays caused by a work zone on any location of a New Jersey freeway can be predicted. To this end, tremendous amounts of data from different sources were collected to establish the relationship between the model inputs and outputs. A comparative analysis was conducted, and results indicate that the proposed model outperforms others in terms of the least root mean square error (RMSE. The proposed hybrid model can be used to calculate contractor penalty in terms of cost overruns as well as incentive reward schedule in case of early work competition. Additionally, it can assist work zone planners in determining the best start and end times of a work zone for developing and evaluating traffic mitigation and management plans.

  2. Participatory Democracy, Community Organizing and the Community Assessment of Freeway Exposure and Health (CAFEH) Partnership.

    Science.gov (United States)

    Sprague Martinez, Linda; Reisner, Ellin; Campbell, Maria; Brugge, Doug

    2017-02-04

    Background: Conflicting interests, power imbalance and relationships characterized by distrust are just a few of the many challenges community-academic research partnerships face. In addition, the time it takes to build relationships is often overlooked, which further complicates matters and can leave well-intentioned individuals re-creating oppressive conditions through inauthentic partnerships. This paper presents a novel approach of using meeting minutes to explore partnership dynamics. The Community Assessment of Freeway Exposure and Health (CAFEH) partnership is used as an illustrative case study to identify how community academic partnerships overcome the challenges associated with community-based participatory research (CBPR). CAFEH is a study of ultrafine particle exposure (UFP) near highways in the Boston, MA area. Methods: Qualitative analysis was applied to meeting minutes and process evaluation reports from the first three years of the CAFEH study (n = 73 files). In addition, a group meeting was held with project partners in order to contextualize the findings from the document analysis. Results: The three most commonly referenced challenges included language barriers, the overall project structure and budgetary constraints. Meanwhile, a heavy emphasis on process and an approach steeped in participatory democracy facilitated CAFEH's ability to overcome these challenges, as well as sustain and augment strong partnership ties. Conclusions: This experience suggests that leadership that incorporates an organizing approach and a transformational style facilitates CBPR processes and helps teams surmount challenges.

  3. Strategy for the Identification of an INL Comprehensive Utility Corridor

    Energy Technology Data Exchange (ETDEWEB)

    John Reisenauer

    2011-05-01

    be used or are not economically viable. Specific detailed studies will need to be conducted on a case-by-case basis to clearly identify which sections along the perimeter can and cannot be used. Option 2, in this document, identifies areas along existing highways that could be a viable option. However, discussions would have to take place with the State of Idaho to use their easement as part of the corridor and mission impact would need to be evaluated if a specific request was made to the Department of Energy, Idaho Operations Office. Option 3, in this document, is a combination of Options 1 and 2. This option provides the most flexibility to minimize impacts to INL missions. As with the other two options, discussions and agreements with the State of Idaho would be needed and any specific route would need to be thoroughly evaluated for impact, implementation, and operability beyond just a strategy.

  4. Developing infrastructure for electric passenger-cars in the corridor between Southern Scandinavia and Germany - Workshop Protocol

    DEFF Research Database (Denmark)

    Guasco, Clement; Jespersen, Per Homann; Lohse, Sandrina

    2012-01-01

    and academic institutions. A strategy for the development of infrastructure for electric passenger-cars in the corridor was formed using the “Future Creating” methodology. The workshop was part of the SCANDRIA Action Programme and pointed towards ways for e-mobility in the region. The workshop also provided...

  5. National Borders and Transport corridors in Europe: Evidence of linkages in the Dublin-Belfast corridor

    DEFF Research Database (Denmark)

    Petrov, Laura Oana; Williams, Brendan; Shahumyan, Harutyun;

    2012-01-01

    . The growth of urban areas is associated with acces-sibility to transportation routes, and has become the most important factor in landscape and land use change throughout Europe. Apart from providing links between cities, transport corridors are also exten-sions of cities' functionality which allow...... Member States (MS) where a new phase of urbanization is un-derway, dramatically changing land use patterns. The aim of the present work is to reflect on the European perspective concerning spatial development strategies, particularly cross-border transport corridors; to assess the role......Europe’s urban life focuses around a major network of cities, which exchange population, goods, and services of every kind both within regions and across borders. By their very nature, urban questions thus have a transnational dimension, and constitute a fruitful area of Euro-pean cooperation...

  6. Western Energy Corridor -- Energy Resource Report

    Energy Technology Data Exchange (ETDEWEB)

    Leslie Roberts; Michael Hagood

    2011-06-01

    The world is facing significant growth in energy demand over the next several decades. Strategic in meeting this demand are the world-class energy resources concentrated along the Rocky Mountains and northern plains in Canada and the U.S., informally referred to as the Western Energy Corridor (WEC). The fossil energy resources in this region are rivaled only in a very few places in the world, and the proven uranium reserves are among the world's largest. Also concentrated in this region are renewable resources contributing to wind power, hydro power, bioenergy, geothermal energy, and solar energy. Substantial existing and planned energy infrastructure, including refineries, pipelines, electrical transmission lines, and rail lines provide access to these resources.

  7. EVOLUTION AND DEVELOPMENT OF GUANGZHOU-HONG KONG CORRIDOR

    Institute of Scientific and Technical Information of China (English)

    LI Ping; CAO Xiao-shu

    2005-01-01

    With its rapid development in the past two decades, the Pearl River Delta has become one of the most developed regions in China. During this period, an important corridor between Hong Kong and Guangzhou has emerged and shaped the spatial structure of the region. The growth of this region has been greatly marched with the twin poles of Guangzhou and Hong Kong, and the economic and social development h. as taken place in a corridor between these two metropolises. This paper provides an analysis of the significance of this corridor in terms of its infrastructure, population, land use, and economic development. Massive infrastructure construction in the corridor has played an important role in its development. The corridor has high-frequent transport, and each transport mode has contributed in a different way to the process of development of the corridor, With high land use intensity and high population density, it is developing the characteristics of a megalopolis. As a pathway of connection between Guangzhou and Hong Kong, the corridor includes not only physical infrastructure, such as roads, railways and airports, but also logistics operations, human resources, information and capital, which plays important roles in accelerating business development. It demonstrates how this Main Street has become one of the most important factors in regional development.

  8. Requirements Definition for ORNL Trusted Corridors Project

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Randy M [ORNL; Hill, David E [ORNL; Smith, Cyrus M [ORNL; DeNap, Frank A [ORNL; White, James D [ORNL; Gross, Ian G [ORNL; Gorman, Bryan L [ORNL; Hively, Lee M [ORNL; Abercrombie, Robert K [ORNL

    2008-02-01

    The ORNL Trusted Corridors Project has several other names: SensorNet Transportation Pilot; Identification and Monitoring of Radiation (in commerce) Shipments (IMR(ic)S); and Southeastern Transportation Corridor Pilot (SETCP). The project involves acquisition and analysis of transportation data at two mobile and three fixed inspection stations in five states (Kentucky, Mississippi, South Carolina, Tennessee, and Washington DC). Collaborators include the State Police organizations that are responsible for highway safety, law enforcement, and incident response. The three states with fixed weigh-station deployments (KY, SC, TN) are interested in coordination of this effort for highway safety, law enforcement, and sorting/targeting/interdiction of potentially non-compliant vehicles/persons/cargo. The Domestic Nuclear Detection Office (DNDO) in the U.S. Department of Homeland Security (DHS) is interested in these deployments, as a Pilot test (SETCP) to identify Improvised Nuclear Devices (INDs) in highway transport. However, the level of DNDO integration among these state deployments is presently uncertain. Moreover, DHS issues are considered secondary by the states, which perceive this work as an opportunity to leverage these (new) dual-use technologies for state needs. In addition, present experience shows that radiation detectors alone cannot detect DHS-identified IND threats. Continued SETCP success depends on the level of integration of current state/local police operations with the new DHS task of detecting IND threats, in addition to emergency preparedness and homeland security. This document describes the enabling components for continued SETCP development and success, including: sensors and their use at existing deployments (Section 1); personnel training (Section 2); concept of operations (Section 3); knowledge discovery from the copious data (Section 4); smart data collection, integration and database development, advanced algorithms for multiple sensors, and

  9. 2007 Weather and Aeolian Sand-Transport Data from the Colorado River Corridor, Grand Canyon, Arizona

    Science.gov (United States)

    Draut, Amy E.; Andrews, Timothy; Fairley, Helen C.; Brown, Christopher R.

    2009-01-01

    Weather data constitute an integral part of ecosystem monitoring in the Colorado River corridor and are particularly valuable for understanding processes of landscape change that contribute to the stability of archeological sites. Data collected in 2007 are reported from nine weather stations in the Colorado River corridor through Grand Canyon, Ariz. The stations were deployed in February and March 2007 to measure wind speed and direction, rainfall, air temperature, relative humidity, and barometric pressure. Sand traps near each weather station collect windblown sand, from which daily aeolian sand-transport rates are calculated. The data reported here were collected as part of an ongoing study to test and evaluate methods for quantifying processes that affect the physical integrity of archeological sites along the river corridor; as such, these data can be used to identify rainfall events capable of causing gully incision and to predict likely transport pathways for aeolian sand, two landscape processes integral to the preservation of archeological sites. Weather data also have widespread applications to other studies of physical, cultural, and biological resources in Grand Canyon. Aeolian sand-transport data reported here, collected in the year before the March 2008 High-Flow Experiment (HFE) at Glen Canyon Dam, represent baseline data against which the effects of the 2008 HFE on windblown sand will be compared in future reports.

  10. Corridors and some ecological and evolutionary consequences of connectivity.

    Energy Technology Data Exchange (ETDEWEB)

    Orrock, John L

    2004-07-01

    Abstract - By connecting disjunct patches, corridors may offset the effects of fragmentation by promoting gene flow and population persistence. However, the ultimate effect of corridors on a focal species may hinge upon two considerations: how corridors may affect ecological interactions that impinge upon that species, and how corridors might affect the fixation of novel alleles that ultimately determine fitness and persistence. Using an experimental landscape, I show that corridor-mediated changes in patch shape change seed predation in connected and unconnected patches, and shift the behavior, abundance, and distribution of seed predators. Rodent seed predators removed more seeds in connected patches, arthropod seed predators removed more seeds in rectangular patches, and avian seed predation did not differ due to patch type. Rodent foraging was greater in the interior of connected patches because changes in patch shape influenced risk perceived by rodents while foraging. Ant communities were also affected by changes in patch shape caused by corridors, rather than corridor effects per se. The distribution and abundance of ants differed among edge-rich areas (corridors and wings), edges, and the patch interior. In rectangular patches, fire ants (Solenopsis spp.) had negative impacts on other ant species. By changing the activity of rodents, and the composition of ant communities, corridors may have important impacts on seeds. Bird-dispersed seeds may benefit from increased dispersal among connected patches, but connected patches also have greater predation risk. Using a simulation model, I demonstrate that gene flow between a stable population and a population that experiences local extinction or a reduction in size (e.g. due to natural or anthropogenic disturbance) can dramatically affect fixation of alleles in the stable population. Alone or in concert, frequent disturbance, high rates of movement, and low habitat quality make it more likely that connectivity

  11. Thermal-Structural Analysis of the MacArthur Maze Freeway Collapse

    Energy Technology Data Exchange (ETDEWEB)

    Noble, C R; Wemhoff, A P; McMichael, L D

    2008-02-26

    At approximately 3:41 AM on the morning of April 29, 2007, a tractor-trailer rig carrying 8,600 gallons (32.6 m{sup 3}) of fuel overturned on Interstate 880 in Oakland, CA. The resultant fire weakened the surrounding steel superstructure and caused a 50-yard (45.7 m) long section of the above connecting ramp from Interstate 80 to Interstate 580 to fail in approximately 18 minutes. In this study, we performed a loosely-coupled thermal-structural finite element analysis of the freeway using the LLNL Engineering codes NIKE3D, DYNA3D and TOPAZ3D. First, we applied an implicit structural code to statically initialize the stresses and displacements in the roadway at ambient conditions due to gravity loading. Next, we performed a thermal analysis by approximating the tanker fire as a moving box region of uniform temperature. This approach allowed for feasible calculation of the fire-to-structure radiative view factors and convective heat transport. We used a mass scaling methodology in the thermal analysis to reduce the overall simulation time so an explicit structural analysis could be used, which provided a more computationally efficient simulation of structural failure. Our approach showed structural failure of both spans due to thermal softening under gravity loading at approximately 20 minutes for a fixed fire temperature of 1200 C and fixed thermal properties. When temperature-dependent thermal properties were applied, the south and north spans collapsed at approximately 10 minutes and 16 minutes, respectively. Finally, we performed a preliminary fully-coupled analysis of the system using the new LLNL implicit multi-mechanics code Diablo. Our investigation shows that our approach provides a reasonable first-order analysis of the system, but improved modeling of the transport properties and the girder-box beam connections is required for more accurate predictions.

  12. 76 FR 65561 - Multistate Corridor Operations and Management Program

    Science.gov (United States)

    2011-10-21

    ... Federal Highway Administration Multistate Corridor Operations and Management Program AGENCY: Federal... Operations and Management (MCOM) Program authorized by the Safe, Accountable, Flexible, Efficient... transportation challenges facing the efficient and effective operation and management of...

  13. Maximum currents in the Northeast Corridor Reserve during November 2013.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 2D numerical model, CMS-Flow, was implemented for the Northeast Corridor Reserve (NECR) using a telescoping grid. Tide and wind forcing was provided to the model...

  14. Conservation Lands and Preserves, Private - Volusia County Conservation Corridor

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The Volusia Conservation Corridor (VCC) is a mosaic of contiguous parcels of land, approximately 55,000 acres in size, which sits essentially in the middle of the...

  15. 46 CFR 393.3 - Marine Highway Corridors.

    Science.gov (United States)

    2010-10-01

    ..., landside infrastructure maintenance savings, improved safety, and added system resiliency. Additional... and performance. (3) Involved Parties. Provide the organizational structure of the parties... infrastructure maintenance costs, safety and system resiliency. Specify if the Marine Highway Corridor represents...

  16. Conservation Lands and Preserves, Private - Volusia County Conservation Corridor

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — The Volusia Conservation Corridor (VCC) is a mosaic of contiguous parcels of land, approximately 55,000 acres in size, which sits essentially in the middle of the...

  17. 76 FR 3695 - Environmental Impact Statement: Interstate 64 Corridor, Virginia

    Science.gov (United States)

    2011-01-20

    ... Federal Highway Administration Environmental Impact Statement: Interstate 64 Corridor, Virginia AGENCY... Administration is issuing this notice to advise the public of its intent to prepare an Environmental Impact..., Senior Environmental Specialist, Federal Highway Administration, Post Office Box 10249, Richmond...

  18. Student housing unit in a floor area without corridors

    OpenAIRE

    Cekić Nikola; Vasov Miomir; Bjelić Igor

    2013-01-01

    This paper treats the issues of position and urbarchitectonic-functional organization of a housing unit in a floor area without corridors in a student hostel. The authors advocate a new, more rational and functional concept in which the student room is not in direct contact with the corridor communication, but belongs to the housing unit, student apartment for 4-6 users. In a more rational organized volume, the living of the students is more comfortable and has a different character. Th...

  19. Road network in an agrarian landscape: Potential habitat, corridor or barrier for small mammals?

    Science.gov (United States)

    Redon (de), Louis; Le Viol, Isabelle; Jiguet, Frédéric; Machon, Nathalie; Scher, Olivier; Kerbiriou, Christian

    2015-01-01

    If the negative effects of road networks on biodiversity are now recognized, their role as barriers, habitats or corridors remain to be clarified in human altered landscapes in which road verges often constitute the few semi-natural habitats where a part of biodiversity important for ecosystem functioning may maintain. In human-dominated landscape, their roles are crucial to precise in comparison to other habitats for small mammal species considered as major natural actors (pests (voles) or biological control agents (shrew)). We studied these roles through the comparison of small mammal abundance captured (418 individuals belonging to 8 species) using non-attractive pitfall traps (n = 813) in 176 sampled sites distributed in marginal zones of road and crop, in natural areas and in fields. We examined the effect of roadside width and isolation of sites. We found the higher small mammal abundances in roadside verges and an effect of width margins for shrews. The significant effect of the distance to the next adjacent natural habitat at the same side of the road on the relative abundance of Sorex coronatus, and the absence of a significant effect of distance to the next natural habitat at the opposite side of road, suggest that highway and road verges could be used as corridor for their dispersal, but have also a barrier effect for shrews. Our results show that in intensive agricultural landscapes roadside and highway verges may often serve as refuge, habitat and corridor for small mammals depending on species and margin characteristics.

  20. Road-corridor planning in the EIA procedure in Spain. A review of case studies

    Energy Technology Data Exchange (ETDEWEB)

    Loro, Manuel, E-mail: manuel.loro@upm.es [Department of Urban and Regional Planning and Environment, Civil Engineering School, Universidad Politécnica de Madrid, Prof. Aranguren s/n, 28040 Madrid (Spain); Transport Research Centre (TRANSyT-UPM) Universidad Politécnica de Madrid, ETSI Caminos, Canales y Puertos, Prof. Aranguren s/n, 28040 Madrid (Spain); Centro de investigación del transporte, TRANSyT-UPM, ETSI Caminos, Canales y Puertos, Universidad Politécnica de Madrid, Prof. Aranguren s/n, 28040 Madrid (Spain); Arce, Rosa M., E-mail: rosa.arce.ruiz@upm.es [Department of Urban and Regional Planning and Environment, Civil Engineering School, Universidad Politécnica de Madrid, Prof. Aranguren s/n, 28040 Madrid (Spain); Transport Research Centre (TRANSyT-UPM) Universidad Politécnica de Madrid, ETSI Caminos, Canales y Puertos, Prof. Aranguren s/n, 28040 Madrid (Spain); Centro de investigación del transporte, TRANSyT-UPM, ETSI Caminos, Canales y Puertos, Universidad Politécnica de Madrid, Prof. Aranguren s/n, 28040 Madrid (Spain); Ortega, Emilio, E-mail: e.ortega@upm.es [Transport Research Centre (TRANSyT-UPM) Universidad Politécnica de Madrid, ETSI Caminos, Canales y Puertos, Prof. Aranguren s/n, 28040 Madrid (Spain); Centro de investigación del transporte, TRANSyT-UPM, ETSI Caminos, Canales y Puertos, Universidad Politécnica de Madrid, Prof. Aranguren s/n, 28040 Madrid (Spain); Department of Construction and Rural Roads, Forestry Engineering School, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain); and others

    2014-01-15

    The assessment of different alternatives in road-corridor planning must be based on a number of well-defined territorial variables that serve as decision making criteria, and this requires a high-quality preliminary environmental assessment study. In Spain the formal specifications for the technical requirements stipulate the constraints that must be considered in the early stages of defining road corridors, but not how they should be analyzed and ranked. As part of the feasibility study of a new road definition, the most common methodology is to establish different levels of Territorial Carrying Capacity (TCC) in the study area in order to summarize the territorial variables on thematic maps and to ease the tracing process of road-corridor layout alternatives. This paper explores the variables used in 22 road-construction projects conducted by the Ministry of Public Works that were subject to the Spanish EIA regulation and published between 2006 and 2008. The aim was to evaluate the quality of the methods applied and the homogeneity and suitability of the variables used for defining the TCC. The variables were clustered into physical, environmental, land-use and cultural constraints for the purpose of comparing the TCC values assigned in the studies reviewed. We found the average quality of the studies to be generally acceptable in terms of the justification of the methodology, the weighting and classification of the variables, and the creation of a synthesis map. Nevertheless, the methods for assessing the TCC are not sufficiently standardized; there is a lack of uniformity in the cartographic information sources and methodologies for the TCC valuation. -- Highlights: • We explore 22 road-corridor planning studies subjected to the Spanish EIA regulation. • We analyze the variables selected for defining territorial carrying capacity. • The quality of the studies is acceptable (methodology, variable weighting, mapping). • There is heterogeneity in the

  1. Monitoring vegetation water uptake in a semiarid riparian corridor

    Science.gov (United States)

    Robinson, J.; Ochoa, C. G.; Leonard, J.

    2015-12-01

    With a changing global climate and growing demand for water throughout the world, responsible and sustainable land and water resource management practices are becoming increasingly important. Accounting for the amount of water used by riparian vegetation is a critical element for better managing water resources in arid and semiarid environments. The objective of this study was to determine water uptake by selected riparian vegetative species in a semiarid riparian corridor in North-Central Oregon. Exo-skin sap flow sensors (Dynamax, Houston, TX, U.S.A.) were used to measure sap flux in red alder (Alnus rubra) trees, the dominant overstory vegetation at the field site. Xylem sap flow data was collected from selected trees at the field site and in a greenhouse setting. Transpiration rates were determined based on an energy balance method, which makes it possible to estimate the mass flow of sap by measuring the velocity of electrical heat pulses through the plant stem. Preliminary field results indicate that red alder tree branches of about 1 inch diameter transpire between 2 and 6 kg of water/day. Higher transpiration rates of up to 7.3 kg of water/day were observed under greenhouse conditions. Streamflow and stream water temperature, vegetation characteristics, and meteorological data were analyzed in conjunction with transpiration data. Results of this study provide insight on riparian vegetation water consumption in water scarce ecosystems. This study is part of an overarching project focused on climate-vegetation interactions and ecohydrologic processes in arid and semiarid landscapes.

  2. Two-level Trajectory-Based Routing Protocol for Vehicular Ad Hoc Networks in Freeway and Manhattan Environments

    Directory of Open Access Journals (Sweden)

    Floriano De Rango

    2009-11-01

    Full Text Available This paper focuses on the routing protocol issue in two important environments for Vehicular Ad Hoc Networks (VANET: Manhattan and the Freeway. A novel protocol called Two-level Trajectory Based Routing (TTBR protocol is proposed. Deterministic vehicles movement permits advantage to be taken of the map info to build a specific local trajectory to reach the destination node. However, in order to offer network scalability also a high level cell-based trajectory is applied to have a coarse knowledge of the cell where the destination node is moving. Our proposal needs Peer Servers and Grid subdivision of the space. Simulation results were assessed to show the improvements and scalability offered by TTBR in comparison with other Ad Hoc networks protocols such as AODV and GPSR. Performance Evaluation was evaluated in terms of Normalized Control Overhead and Data Packet Delivery Ratio. TTBR is more performing than AODV for a high speed and high density scenario for both the Manhattan and Freeway scenarios.

  3. Crash Risk Prediction Modeling Based on the Traffic Conflict Technique and a Microscopic Simulation for Freeway Interchange Merging Areas.

    Science.gov (United States)

    Li, Shen; Xiang, Qiaojun; Ma, Yongfeng; Gu, Xin; Li, Han

    2016-11-19

    This paper evaluates the traffic safety of freeway interchange merging areas based on the traffic conflict technique. The hourly composite risk indexes (HCRI) was defined. By the use of unmanned aerial vehicle (UAV) photography and video processing techniques, the conflict type and severity was judged. Time to collision (TTC) was determined with the traffic conflict evaluation index. Then, the TTC severity threshold was determined. Quantizing the weight of the conflict by direct losses of different severities of freeway traffic accidents, the calculated weight of the HCRI can be obtained. Calibration of the relevant parameters of the micro-simulation simulator VISSIM is conducted by the travel time according to the field data. Variables are placed into orthogonal tables at different levels. On the basis of this table, the trajectory file of every traffic condition is simulated, and then submitted into a surrogate safety assessment model (SSAM), identifying the number of hourly traffic conflicts in the merging area, a statistic of HCRI. Moreover, the multivariate linear regression model was presented and validated to study the relationship between HCRI and the influencing variables. A comparison between the HCRI model and the hourly conflicts ratio (HCR), without weight, shows that the HCRI model fitting degree was obviously higher than the HCR. This will be a reference to design and implement operational planners.

  4. A Novel Approach to Extract Significant Patterns of Travel Time Intervals of Vehicles from Freeway Gantry Timestamp Sequences

    Directory of Open Access Journals (Sweden)

    Jing-Doo Wang

    2017-08-01

    Full Text Available It is attractive to extract and determine the key features of traffic patterns for mitigating road congestion and predicting travel time of vehicles in traffic analysis. Based on the previous work that is a scalable approach via a Hadoop MapReduce programming model, this paper aims to extract significant patterns of travel time intervals of vehicles from freeway traffic in Taiwan, and meanwhile to compute the statistics of these patterns from the point of view one may concern. Experimental resources are the records of timestamp gantry sequences of vehicles passed in five months from 2016/11 to 2017/3 that were downloaded from the Traffic Data Collection System, one of Taiwan government open data platforms. To select one specific gantry sequence for demonstration, the longest sequence on the trip within the Taiwan National Freeway No. 5 is selected. Experimental results show that some statistics of vehicle travel time intervals according to 24 h per day are computed for illustration. These statistics can not only provide clues to experts to analyze traffic congestions, but also help drivers how to avoid rush hours. Furthermore, this work is able to handle a larger amount of real data and be promising for further traffic and transportation research in the future.

  5. Crash Risk Prediction Modeling Based on the Traffic Conflict Technique and a Microscopic Simulation for Freeway Interchange Merging Areas

    Directory of Open Access Journals (Sweden)

    Shen Li

    2016-11-01

    Full Text Available This paper evaluates the traffic safety of freeway interchange merging areas based on the traffic conflict technique. The hourly composite risk indexes (HCRI was defined. By the use of unmanned aerial vehicle (UAV photography and video processing techniques, the conflict type and severity was judged. Time to collision (TTC was determined with the traffic conflict evaluation index. Then, the TTC severity threshold was determined. Quantizing the weight of the conflict by direct losses of different severities of freeway traffic accidents, the calculated weight of the HCRI can be obtained. Calibration of the relevant parameters of the micro-simulation simulator VISSIM is conducted by the travel time according to the field data. Variables are placed into orthogonal tables at different levels. On the basis of this table, the trajectory file of every traffic condition is simulated, and then submitted into a surrogate safety assessment model (SSAM, identifying the number of hourly traffic conflicts in the merging area, a statistic of HCRI. Moreover, the multivariate linear regression model was presented and validated to study the relationship between HCRI and the influencing variables. A comparison between the HCRI model and the hourly conflicts ratio (HCR, without weight, shows that the HCRI model fitting degree was obviously higher than the HCR. This will be a reference to design and implement operational planners.

  6. Energy transport corridors: the potential role of Federal lands in states identified by the Energy Policy Act of 2005, section 368(b).

    Energy Technology Data Exchange (ETDEWEB)

    Krummel, J.; Hlohowskyj, I.; Kuiper, J.; Kolpa, R.; Moore, R.; May, J.; VanKuiken, J.C.; Kavicky, J.A.; McLamore, M.R.; Shamsuddin, S. (Decision and Information Sciences); ( EVS)

    2011-09-01

    On August 8, 2005, the President signed the Energy Policy Act of 2005 (EPAct) into law. In Subtitle F of EPAct, Congress set forth various provisions that would change the way certain federal agencies (Agencies) coordinate to authorize the use of land for a variety of energy-related purposes. As part of Subtitle F of EPAct, Section 368 addresses the issue of energy transportation corridors on federal land for oil, gas, and hydrogen pipelines, as well as electricity transmission and distribution facilities. Because of the critical importance of improving the nation's electrical transmission grid, Congress recognized that electricity transmission issues should receive added attention when the Agencies address corridor location and analysis issues. In Section 368, Congress specifically directed the Agencies to consider the need for upgraded and new facilities to deliver electricity: In carrying out [Section 368], the Secretaries shall take into account the need for upgraded and new electricity transmission and distribution facilities to (1) improve reliability; (2) relieve congestion; and (3) enhance capability of the national grid to deliver electricity. Section 368 does not require the Agencies to consider or approve specific projects, applications for rights-of-way (ROWs), or other permits within designated energy corridors. Importantly, Section 368 does not direct, license, or otherwise permit any on-the-ground activity of any sort. If an applicant is interested in obtaining an authorization to develop a project within any corridor designated under Section 368, the applicant would have to apply for a ROW authorization and applicable permits. The Agencies would consider each application by applying appropriate project-specific reviews under requirements of laws and related regulations, including, but not limited to, the National Environmental Policy Act (NEPA), the Clean Water Act, the Clean Air Act, Section 7 of the Endangered Species Act (ESA), and Section

  7. THE SNOW CONDITION, THE AVALANCHES CAUSED AND THE DYNAMIC OF THE AVALANCHES CORRIDORS DURING THE WINTER 2007-2008. CASE STUDY, PADINILE FRUMOASE (PIATRA CRAIULUI MOUNTAINS, ROMANIA

    Directory of Open Access Journals (Sweden)

    ANCA MUNTEANU

    2013-04-01

    Full Text Available The snow condition, the avalanches caused and the dynamic of the avalanches corridors during the winter 2007-2008. Case study, Padinile Frumoase (Piatra Craiului Mountains, Romania. In this paper we aim to present in detail the situations generated by meteorological and morphological parameters, which determined the generation of avalanches of different intensities, on five avalanches corridors in the winter 2007-2008. These are situated in the area named Padinile Frumoase, in the north-eastern part of the Piatra Craiului Mountains, which are situated in the central part of Romania and which belong to the Meridional Carpathians. The relief is represented by a calcareous- conglomeratic ridge, in the high part, the peak reaches over 2000 m altitude. Local conditions determine the forming of avalanches, which are oriented on well defined corridors, along the temporary hydrographic network. By studying the evolution of meteorological parameters and their overlapping with local morphological parameters, the existence of some favourable conditions for the apparition of avalanches were detected. There were noticed both active corridors with traces of avalanches, and inactive corridors on which it was not noticed the manifestation of these phenomena. The material adds up to the data base about the avalanches from this massif, being the second situation of analysed avalanches for this mountainous space totally situated in the National Park Piatra Craiului.

  8. 23 CFR Appendix C to Subpart A of... - Policy for the Signing and Numbering of Future Interstate Corridors Designated by Section 332 of...

    Science.gov (United States)

    2010-04-01

    ....C. 139(b) C Appendix C to Subpart A of Part 470 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT..., App. C Appendix C to Subpart A of Part 470—Policy for the Signing and Numbering of Future Interstate Corridors Designated by Section 332 of the NHS Designation Act of 1995 or Designated Under 23 U.S.C....

  9. Discussion on Funds Supervision Pattern of Freeway Construction%浅探高速公路建设资金监管模式

    Institute of Scientific and Technical Information of China (English)

    张凌

    2012-01-01

    In recent years, the freeway in China has a rapid development, and the freeway network is gradually formed. Because of the long construction period and huge investment of freeway project, some times, the construction unit may divert the funds of freeway project construction for other ways, which may cause large wage arrears for migrant rural workers, delay duration, and affect the project quality and progress. Therefore, it is very necessary and important to strengthen the supervision of project funds for construction unit.%近年来,我国高速公路快速发展,高速公路网逐步形成.高速公路项目建设期长,投资巨大,施工单位挪用高速公路项目建设资金、用于他途时有发生,容易造成拖欠农民工工资、延误工期、影响工程质量和进度.因此,加强对施工单位的项目建设资金监管,是非常必要和重要的.

  10. 基于MFAC的快速路主辅路的均衡控制%MFAC based balance control for freeway and auxiliary road

    Institute of Scientific and Technical Information of China (English)

    程志辉; 金尚泰

    2015-01-01

    In order to solve the question of trafifc congestion and trafifc resources wasting caused by the density difference between freeway and auxiliary road, the method of balance control for freeway and auxiliary road based on MFAC was proposed. This method introduced the difference balanced control theory and was not restricted by the entrance ramp and auxiliary road intersection model. Only depending on the ramp and intersection trafifc lfow rates as input data and the density of freeway and auxiliary road sections as output data, this method could achieve the model-free adaptive control on strong nonlinear freeway and auxiliary road system, reach to density equilibrium on freeway and auxiliary road system. The simulation results on the Matlab platform showed the effectiveness of the method.%为了解决快速路主辅路交通密度不均衡造成的局部道路拥挤和资源浪费现象,本文提出了基于无模型自适应控制的快速路主辅路均衡控制方法,该方法中引入了均衡控制思想中的差值控制方法,该方法不受入口匝道和辅路交叉口的模型限制,利用入口匝道流率与交叉口离驶率输入数据和主辅路路段密度输出数据,即可实现强非线性快速路主辅路系统的无模型自适应控制,使主辅路达到系统级的密度均衡。Matlab平台上的仿真比较结果表明了这种控制方法的有效性。

  11. 浅析我国高速公路成本控制的措施%Analysis on Cost Control Measures of Freeway in China

    Institute of Scientific and Technical Information of China (English)

    宋传中

    2011-01-01

    Cost control of freeway is full control of the system.To reduce costs and achieve cost advantages is the important measure to make the freeway company get a favorable position in the market competition.This article describes the contents of the freeway cost control, through the analysis of the freeway cost control describes the principles of cost control and explains the cost control measures from progress cost, quality cost, risk cost and procurement cost.The cost control for the freeway enterprise has a very important role and significance in improving economic and social benefits.%高速公路成本控制是系统的全程控制,降低成本,发挥成本优势,是高速公路企业在市场竞争中处于有利地位的重要措施.本文介绍了高速公路成本控制的内容,通过对高速公路成本控制的分析,阐述了高速公路成本控制的原则,并从高速公路的进度成本,质量成本,风险成本以及采购成本的控制四个方面对高速公路的成本控制的措施进行了说明.高速公路成本的控制对于提高高速公路企业的经济效益和社会效益有着非常重要的作用和意义.

  12. Corridor X in Serbia: Approach to spatial planning

    Directory of Open Access Journals (Sweden)

    Milijić Saša

    2003-01-01

    Full Text Available For the infrastructural corridor's area, of the national importance, is predicted making spatial plans of area of special use, as the most complex instruments for the developing and arranging management of these areas. These plans should have an integrative and problem-oriented approach towards development planning and arrangement of such an area, and it is obliged to include: a complex evaluation of state and function of infrastructural system in the corridor; an analysis of infrastructural corridor influence on the development of the planning area and its surrounding; an alternative conception of long-term protection, improvement, organization and use of the planning area; a choice of the priorities and assumption of the realization phases; instructions for the implementation of the plan etc. The approach in making of this category of plans, as well as, experiences in planning, arrangement and use of multimodal corridors, have been considered on the example of Spatial plan of the infrastructural corridor E-75 section Belgrade-Nis area.

  13. China-Pakistan Economic Corridor, Civil-Military Relations and Democracy in Pakistan

    OpenAIRE

    Wolf, Siegfried O.

    2016-01-01

    The China-Pakistan Economic Corridor (CPEC), a multibillion-dollar infrastructure investment project, is heralded as a game changer for Pakistan’s economy. It is part of the major development initiative led by China, known as ‘One Belt, One Road’ (OBOR), connecting Asia with Europe, the Middle East and Africa, and for those involved it evokes hopes, a myriad of interests, and it spurs a geopolitical shift (Ze 2015; 2014, October 2014). However, such a megaproject also raises numerous question...

  14. Attractive Mobile Corridors - The Power of Light Rail Infrastructures

    DEFF Research Database (Denmark)

    Olesen, Mette; Lassen, Claus

    2013-01-01

    Light rail is a popular tool in urban development strategies in many European cities. One argument for choosing a rail-based solution is that it signals stability to investors and will attract development and investments in the corridor. The choice of corridor in the various light rail cities...... are based on different rationalities: generating urban growth by investments in new housing and businesses, regeneration of urban space, facilitation for a car-free urban lifestyle etc. The main argument of this paper is that light rail corridors are not only providing access, but also gentrifies...... and redistributes urban space. Furthermore light rail is not only a physical infrastructure but also an infrastructure of power that is carefully planned and designed creating both mental and physical patterns of mobilities and immobilities. Hence it is important to underline that mobility systems, such as light...

  15. Effects of landscape corridors on seed dispersal by birds.

    Energy Technology Data Exchange (ETDEWEB)

    Levey, Douglas, J.; Bolker, Benjamin M.; Tewksbury, Joshua J.; Sargent, Sarah; Haddad, Nick M.

    2005-07-01

    Levey, Douglas, J., Benjamin M. Bolker, Joshua J. Tewksbury, Sarah Sargent, and Nick M. Haddad. 2005. Effects of landscape corridors on seed dispersal by birds. Science 309:146-148. Abstract: Habitat fragmentation threatens biodiversity by disrupting dispersal. The mechanisms and consequences of this disruption are controversial, primarily because most organisms are difficult to track. We examined the effect of habitat corridors on long-distance dispersal of seeds by birds, and tested whether small-scale (G20 meters) movements of birds could be scaled up to predict dispersal of seeds across hundreds of meters in eight experimentally fragmented landscapes. A simulation model accurately predicted the observed pattern of seed rain and revealed that corridors functioned through edge following behavior of birds. Our study shows how models based on easily observed behaviors can be scaled up to predict landscape-level processes.

  16. FIXED-WING MICRO AERIAL VEHICLE FOR ACCURATE CORRIDOR MAPPING

    Directory of Open Access Journals (Sweden)

    M. Rehak

    2015-08-01

    Full Text Available In this study we present a Micro Aerial Vehicle (MAV equipped with precise position and attitude sensors that together with a pre-calibrated camera enables accurate corridor mapping. The design of the platform is based on widely available model components to which we integrate an open-source autopilot, customized mass-market camera and navigation sensors. We adapt the concepts of system calibration from larger mapping platforms to MAV and evaluate them practically for their achievable accuracy. We present case studies for accurate mapping without ground control points: first for a block configuration, later for a narrow corridor. We evaluate the mapping accuracy with respect to checkpoints and digital terrain model. We show that while it is possible to achieve pixel (3-5 cm mapping accuracy in both cases, precise aerial position control is sufficient for block configuration, the precise position and attitude control is required for corridor mapping.

  17. Colorado Plateau Rapid Ecoregion Assessment Management Question D1: What is the distribution of movement corridors?

    Data.gov (United States)

    Bureau of Land Management, Department of the Interior — This map shows least-cost corridors and large natural habitat blocks. These blocks and corridors may provide an essential network for various species to disperse...

  18. TRANSPORT CORRIDOR "URAL INDUSTRIAL – URAL POLAR": PROBLEMS, EVOLUTION PATHS

    Directory of Open Access Journals (Sweden)

    N.V. Tabakov

    2007-06-01

    Full Text Available The article deals with the theoretic and methodological questions regarding the formation of a transport corridor "Urals industrial – Urals Polar". Analyzed are the main factors that affect the formation of the transport infrastructure. A big effect is centered around the world-view problem, which has to do with the occupation of a human, and the effect of it on nature. Put forth is the possibility to look upon the question of the formation of ma transport corridor "Urals industrial – Urals Polar" in the frame of the forming of the Ural-West-Siberian TPK, taking into account the global transport web.

  19. The China-Pakistan Economic Corridor (CPEC): feasibility and the need for an assessment of India’s role

    OpenAIRE

    Wolf, Siegfried O.

    2016-01-01

    The China-Pakistan Economic Corridor CPEC, a multi-billion dollar infrastructure investment project, is heralded as a game changer for Pakistan’s economy and regional cooperation. Being a crucial part of a major development initiative led by China, known as ‘One Belt, One Road’ (OBOR), to connect Asia with Europe, the Middle East and Africa, the CPEC is much linked to hopes, interests, as well as regional and global geopolitics. However, such a megaproject raises numerous questions especially...

  20. Evaluation of Spatial Development Initiatives: Case studies of the Maputo Development Corridor and the West Coast Investment Initiative

    OpenAIRE

    David Bek; Ian Taylor

    2001-01-01

    Spatial Development Initiatives (SDIs) form an integral part of the South African government strategy to attract investment. SDIs are claimed to be short-term and targeted undertakings to foster economic growth. This working paper reviews two SDI projects, namely the Maputo Development Corridor (MDC) and the West Coast Investment Initiative (WCII). The paper outlines many strengths within the MDC and WCII and draws out lessons to be learned that could improve the delivery of ongoing and futur...

  1. Identifying transit corridors for elephant using a long time-series

    NARCIS (Netherlands)

    Pittiglio, C.; Skidmore, A.K.; Gils, van H.A.M.J.; Prins, H.H.T.

    2012-01-01

    The role of corridors in mitigating the effects of landscape fragmentation on biodiversity is controversial. Recent studies have highlighted the need for new approaches in corridor design using long-term datasets. We present a method to identify transit corridors for elephant at a population scale o

  2. 75 FR 17756 - Blackstone River Valley National Heritage Corridor Commission: Notice of Meeting

    Science.gov (United States)

    2010-04-07

    ... Office of the Secretary Blackstone River Valley National Heritage Corridor Commission: Notice of Meeting... the John H. Chafee Blackstone River Valley National Heritage Corridor Commission will be held on... integrated resource management plan for those lands and waters within the Corridor. The meeting will...

  3. Characterization of organic, metal and trace element PM2.5 species and derivation of freeway-based emission rates in Los Angeles, CA.

    Science.gov (United States)

    Liacos, James W; Kam, Winnie; Delfino, Ralph J; Schauer, James J; Sioutas, Constantinos

    2012-10-01

    On-road particulate matter (PM) was collected during a sampling campaign in March-April of 2011 on two major Los Angeles freeways, I-710 and Route 110. I-710 is a major route for heavy-duty vehicles (HDVs) traveling to and from the Ports of Long Beach and Los Angeles, while Route 110 has a much lower HDV fraction -3.9% versus 11.4%. Two sets of samples were collected for each roadway, each set representing approximately 50°h of on-road sampling. Concurrent sampling at a fixed site at the University of Southern California's (USC) downtown Los Angeles campus provided estimates of urban background levels. Chemical analysis was performed for elemental carbon (EC), organic carbon (OC), polycyclic aromatic hydrocarbons (PAHs), hopanes and steranes, and metals and trace elements. Freeway-based emission rates (ERs) - mass per kilometer of freeway per hour - were calculated using mass concentrations, fuel characteristics, and traffic flow rates. These ERs are presented such that freeways could be treated as a line source of emissions for use in predictive models of population exposure for nearby communities. This data could also be used to assess the exposure of commuters to traffic-related PM2.5 emissions. ERs are compared to data from a previous fixed-site roadside study of I-710 as well as to reconstructed values from a tunnel study. ERs were generally lower (or comparable) on the gasoline-vehicle dominated freeway (Route 110) than the freeway with more diesel trucks (I-710), with EC and pyrene being notably lower on Route 110, findings consistent with the Route 110's lower HDV fraction. We found EC emission rates decreased over time suggesting that efforts to reduce diesel emissions from HDVs at the Ports of Los Angeles and Long Beach have been successful. While ERs for most of the organic species were within the range of values reported by previous studies, the present study found much higher ERs for metals and trace elements. This suggests that the sampling methods

  4. Workshop Protocol 5.1 “Developing infrastructure for electric passenger-cars in the corridor between Southern Scandinavia and Germany”

    DEFF Research Database (Denmark)

    Guasco, Clement Nicolas

    and academic institutions. A strategy for the development of infrastructure for electric passenger-cars in the corridor was formed using the “Future Creating” methodology. The workshop was part of the SCANDRIA Action Programme and pointed towards ways for e-mobility in the region. The workshop also provided...

  5. The Bug river - Corridor in the Pan European

    NARCIS (Netherlands)

    Zingstra, H.L.; Simeonova, V.; Kitnaes, K.

    2009-01-01

    This is the final report of the BBI/Matra project 2006/015 “Protection and Management of the Bug as an Ecological Corridor in the Pan European Ecological Network” and is based on “status reports” written for each of the three riparian countries. The purpose of the project was to investigate the

  6. Corridors of barchan dunes: Stability and size selection

    DEFF Research Database (Denmark)

    Hersen, P.; Andersen, Ken Haste; Elbelrhiti, H.;

    2004-01-01

    Barchans are crescentic dunes propagating on a solid ground. They form dune fields in the shape of elongated corridors in which the size and spacing between dunes are rather well selected. We show that even very realistic models for solitary dunes do not reproduce these corridors. Instead, two in...... for these instabilities to develop are derived and discussed. They turn out to be much smaller than the dune field length. As a conclusion, there should exist further, yet unknown, mechanisms regulating and selecting the size of dunes.......Barchans are crescentic dunes propagating on a solid ground. They form dune fields in the shape of elongated corridors in which the size and spacing between dunes are rather well selected. We show that even very realistic models for solitary dunes do not reproduce these corridors. Instead, two...... instabilities take place. First, barchans receive a sand flux at their back proportional to their width while the sand escapes only from their horns. Large dunes proportionally capture more sand than they lose, while the situation is reversed for small ones: therefore, solitary dunes cannot remain in a steady...

  7. Impressions of Serbia: Tourists on cruises along Corridor 7

    Directory of Open Access Journals (Sweden)

    Dragin Aleksandra S.

    2009-01-01

    Full Text Available This paper deals with cruises along Corridor 7 and the tourist offer of Serbia. The purpose of the paper has been to establish how international tourists see our country during their travels across Serbia on cruises along Corridor 7. The research has been based on the interviews with international tourists who participated in land tours while cruising through Serbia. The interviews, together with the structured questionnaire, were conducted from March to November 2007 with the objectives to establish the following: the structure of the respondents according to the country of origin, gender and age structure, as well as the social and economic structure; what their motives are for cruising along Corridor 7; what is their perception of the value obtained through the tourist product and services during the Corridor 7 cruises and during their stay in Serbia (what they liked best in Serbia; if they were dissatisfied with anything in terms of the tourist offer of Serbia; to what extent their visit complemented or influenced their personal impressions of this country - what their impressions were before and after the visit. The importance of this paper, above all, is in broadening our knowledge about the adequacy of the tourist offer in Serbia in the tourism segment which is the subject of study of the paper.

  8. Safe corridors for K-wiring in phalangeal fractures

    Directory of Open Access Journals (Sweden)

    C Rex

    2015-01-01

    Conclusion: K-wiring through the safe corridor has proved to yield the best clinical results because of least tethering of soft tissues as evidenced by performing "on-table active finger movement test" at the time of surgery. We strongly recommend K-wiring through safe portals in all phalangeal fractures.

  9. Malaysia's Multimedia Super Corridor and Roles of Information Professionals.

    Science.gov (United States)

    Reid, Edna

    In Malaysia, the government is supporting the diffusion of the Internet and is spearheading a project to bring Malaysia into the information age, by helping to design a smart city called the Multimedia Super Corridor (MSC). The MSC is being planned as a high-technology center where world-class multimedia companies can develop state-of-the-art…

  10. Plant community characteristics and their relationships with climate in the Hexi Corridor region of northwestern China

    Institute of Scientific and Technical Information of China (English)

    Peixi SU; Hongbin CHEN; Qiaodi YAN

    2008-01-01

    Species, coverage, density, appearance, important values and above ground biomass of desert plant communities in the Hexi Corridor region in north-western China were investigated. Data on the meteoro-logical factors at the investigation sites were collected. Their relationships were statistically analyzed. The results show that the composition of plant species and total den-sity in the Hexi Corridor region are positively correlated with elevation and longitude, but negatively with latitude. The relation decreases from the southeast to the northwest in this region. In the desert regions with an accumulated temperature of >10℃ greater than 3200℃, the shrubs, including semi-shrubs, occupy dominant positions in the communities. Their importance values reach 100. When the accumulated temperature is about 3000℃, the com-munities are often in some type of transition, either with herbage being the dominant species, with some semi-shrubs or shrubs as companion species, or the dominant species being semi-shrubs with some perennial herbage as companion species. In desert communities with an annual precipitation of over 110 mm, the main life forms of plants are semi-shrubs or perennial herbs. When precip-itation is less than 110 mm, the main life forms of the vegetation are dwarf shrub or annual herbs. In the extreme arid regions with annual precipitation of around 50 mm in the northwestern part of the Hexi Corridor, barely some annual herbage come to life during the rainy season. Desert ecosystems consist of sparse vegetation with small biomass. They change with climate factors and are especially sensitive to precipitation, which is par-ticularly important for their conservation.

  11. The Effect of the Hayward Corridor Improvement Project on Carbon Monoxide Emission

    Science.gov (United States)

    Muhlfelder, M.; Martinez, E.; Maestas, A.; Peek, A.

    2013-12-01

    In August of 2010, construction began on a stretch of road in Downtown Hayward to address a problem with traffic flow. Known as the Hayward Corridor, the project reshaped the flow of traffic, replacing the two way streets of Foothill, Mission, and A Street with a loop between them. This project began with the initiative of reducing congestion in this area and improving access to businesses for pedestrians. The project was expected to have little environmental impact in most common assessments of degree of effect, including particulate matter, ozone and carbon monoxide levels. This report will discuss the effect of the Hayward Corridor Improvement Project on carbon monoxide emission. Data available to the public in the project's Environmental Impact Report shows that carbon monoxide levels before construction began were at an acceptable level according to federal and state standards. Projections for future concentrations both with and without the project show a decrease in carbon monoxide levels due to technological improvements and the gradual replacement of older, less efficient vehicles. The Environmental Impact Report projected that there would be little difference in carbon monoxide levels whether the project took place or not, at an average of 1.67x102 fewer parts per million per 1 hour period of measurement emitted in the case of the project not taking place. While it is not possible to draw a conclusion on what the current carbon monoxide levels would be if the project had not taken place due to the changes in traffic flow and other surrounding roads as a result of the project, the data gathered in June of 2013 suggested that carbon monoxide levels are higher than the values projected in 2007. This report summarizes both the accuracy of these carbon monoxide level projections and the effect of construction on carbon monoxide levels in the Hayward Corridor and the surrounding area.

  12. Improving Urban Corridor that Respect to Public Space

    Science.gov (United States)

    Zahrah, W.; Rahmadhani, N.; Nasution, A. D.; Pane, I. F.

    2017-03-01

    The urban corridor is more than just a linear space to circulation. It is a place for community activities. Since the urban area in Indonesia functionates without guidelines, it is necessary to analyze how this space being used by the community. The objective of the research is to explore the problems in utilization of public space in Dr. Mansur corridor in Medan and to propose some recommendation to improve it. The survey was started by mapping the physical situation that based on urban design aspects and the activities occur. Based on the data, the study identified the problems of the public space utilization. Next, study selected several buildings that significant in generating public life. The study interviewed the building’s owners and users/customers to get their opinion and perception about the using of urban public space utilization in the corridor in relation to their private function. The study analyzed the problems and opportunity to redesign the buildings that respect to public space. Then, the design ideas were presented to the buildings owners to get their response. The result of the observation shows that the fundamental problem in the corridor is the intervention of the private interest to the street as public space. The study indicates that the majority of the buildings owner was not aware that their buildings had distracted the urban public space. However, they gave a positive respond to the design recommendation. The design offered the solution that provided individual needs without intervention to the public realm. The study can contribute to improving urban corridor by educating the community with architecture and urban design.

  13. Energy transport corridors: the potential role of Federal lands in states identified by the Energy Policy Act of 2005, section 368(b).

    Energy Technology Data Exchange (ETDEWEB)

    Krummel, J.; Hlohowskyj, I.; Kuiper, J.; Kolpa, R.; Moore, R.; May, J.; VanKuiken, J.C.; Kavicky, J.A.; McLamore, M.R.; Shamsuddin, S. (Decision and Information Sciences); ( EVS)

    2011-09-01

    On August 8, 2005, the President signed the Energy Policy Act of 2005 (EPAct) into law. In Subtitle F of EPAct, Congress set forth various provisions that would change the way certain federal agencies (Agencies) coordinate to authorize the use of land for a variety of energy-related purposes. As part of Subtitle F of EPAct, Section 368 addresses the issue of energy transportation corridors on federal land for oil, gas, and hydrogen pipelines, as well as electricity transmission and distribution facilities. Because of the critical importance of improving the nation's electrical transmission grid, Congress recognized that electricity transmission issues should receive added attention when the Agencies address corridor location and analysis issues. In Section 368, Congress specifically directed the Agencies to consider the need for upgraded and new facilities to deliver electricity: In carrying out [Section 368], the Secretaries shall take into account the need for upgraded and new electricity transmission and distribution facilities to (1) improve reliability; (2) relieve congestion; and (3) enhance capability of the national grid to deliver electricity. Section 368 does not require the Agencies to consider or approve specific projects, applications for rights-of-way (ROWs), or other permits within designated energy corridors. Importantly, Section 368 does not direct, license, or otherwise permit any on-the-ground activity of any sort. If an applicant is interested in obtaining an authorization to develop a project within any corridor designated under Section 368, the applicant would have to apply for a ROW authorization and applicable permits. The Agencies would consider each application by applying appropriate project-specific reviews under requirements of laws and related regulations, including, but not limited to, the National Environmental Policy Act (NEPA), the Clean Water Act, the Clean Air Act, Section 7 of the Endangered Species Act (ESA), and Section

  14. Louisiana Speaks Regional Vision Transit Corridors, UTM Zone 15N NAD 83, Louisiana Recovery Authority (2007), [louisiana_speaks_vision_transit_corridors

    Data.gov (United States)

    Louisiana Geographic Information Center — This GIS shapefile data illustrates the primary and secondary transit corridors included in the Louisiana Speaks Regional Plan Vision. This network accommodates a...

  15. Louisiana Speaks Transportation Option B Transit Corridors, UTM Zone 15N NAD 83, Louisiana Recovery Authority (2007), [louisiana_speaks_transportation_option_b_transit_corridors

    Data.gov (United States)

    Louisiana Geographic Information Center — This GIS shapefile data illustrates the regional, subregional, and local transit corridors included in the Louisiana Speaks Regional Plan community growth option of...

  16. Louisiana Speaks Transportation Option C Transit Corridors, UTM Zone 15N NAD 83, Louisiana Recovery Authority (2007), [louisiana_speaks_transportation_option_c_transit_corridors

    Data.gov (United States)

    Louisiana Geographic Information Center — This GIS shapefile data illustrates the regional, subregional, and local transit corridors included in the Louisiana Speaks Regional Plan community growth option of...

  17. Using Discrete Element Method to Simulate Influence of Vertical Joints and Upward Groundwater on The Stability of Dip Slope: A Case Study on Formosa Freeway

    Science.gov (United States)

    Lu, An; Hsieh, Pei-Chen; Wu, Liang-Chun; Lin, Ming-Lang

    2017-04-01

    Earthquake and rainfall weakening potential sliding surface are common causes of dip slope failure. But in recent years, certain dip slopes failure, for example dip slope sliding without rain on the roadside of Formosa Freeway in northern Taiwan, are caused by uplift groundwater in vertical joints eventually weakening the potential sliding surface. The mechanism of sliding failure should be analyzed in more detail. Furthermore, prestress dissipating in anchors causing dip slope failure is also considered in this study. In this study, conceptual model is simplified from the case of Formosa Freeway in northern Taiwan and the main control factors including angle of slope, stratum, attitude of joints. In addition, drilling data, such as hydraulic conductivity, strength, friction angle and cohesion, are utilized to discuss mechanism and dominant factors of dip slope failure caused by uplift groundwater in vertical joints. UDEC(Universal Distinct Element Code) which is particularly well suited to problems involving jointed media and has been used extensively in stability analysis of jointed rock slopes is utilized in this study. The influence of external factors such as groundwater pressure on block sliding and deformation can also be simulated in UDEC. When the results from numerical simulation fit the condition of slope failure on the roadside of Formosa Freeway, the influence of prestress dissipating in anchors on slope stability is considered subsequently. Finally, simulation results by UDEC are compared with previous research results by FLAC, and discuss the difference between each other.

  18. Comparison and Analysis of the Different Maintenance Strategy in Freeway%高速公路不同养护策略的对比分析

    Institute of Scientific and Technical Information of China (English)

    乐兴堃; 索智; 李振; 徐世法

    2012-01-01

    Taking the long-term maintenance of a freeway as example,combined with two maintenance plans of the preventive maintenance and the correction maintenance,two maintenance modes are established,and the changing trend of the all pavement performance index with the two maintenance plans is obtained.Finally,compared with the two kinds of maintenance mode by the road service life,economic benefits and road with properties,it shows the superiority of the preventive maintenance in freeway maintenance,and calls for using the preventive maintenance in the freeway.%以某高速公路长期养护为例,从结合预防性养护规划和单纯矫正性养护规划两个方面出发,建立两种长期的养护计划方案,得到两种养护方案下各路面性能指数的变化趋势.最后在高速公路的使用寿命、经济效益和路用性能三个方面,说明预防性养护在高速公路养护中的优越性,并倡导在高速公路养护中积极运用预防性养护.

  19. A combined M5P tree and hazard-based duration model for predicting urban freeway traffic accident durations.

    Science.gov (United States)

    Lin, Lei; Wang, Qian; Sadek, Adel W

    2016-06-01

    The duration of freeway traffic accidents duration is an important factor, which affects traffic congestion, environmental pollution, and secondary accidents. Among previous studies, the M5P algorithm has been shown to be an effective tool for predicting incident duration. M5P builds a tree-based model, like the traditional classification and regression tree (CART) method, but with multiple linear regression models as its leaves. The problem with M5P for accident duration prediction, however, is that whereas linear regression assumes that the conditional distribution of accident durations is normally distributed, the distribution for a "time-to-an-event" is almost certainly nonsymmetrical. A hazard-based duration model (HBDM) is a better choice for this kind of a "time-to-event" modeling scenario, and given this, HBDMs have been previously applied to analyze and predict traffic accidents duration. Previous research, however, has not yet applied HBDMs for accident duration prediction, in association with clustering or classification of the dataset to minimize data heterogeneity. The current paper proposes a novel approach for accident duration prediction, which improves on the original M5P tree algorithm through the construction of a M5P-HBDM model, in which the leaves of the M5P tree model are HBDMs instead of linear regression models. Such a model offers the advantage of minimizing data heterogeneity through dataset classification, and avoids the need for the incorrect assumption of normality for traffic accident durations. The proposed model was then tested on two freeway accident datasets. For each dataset, the first 500 records were used to train the following three models: (1) an M5P tree; (2) a HBDM; and (3) the proposed M5P-HBDM, and the remainder of data were used for testing. The results show that the proposed M5P-HBDM managed to identify more significant and meaningful variables than either M5P or HBDMs. Moreover, the M5P-HBDM had the lowest overall mean

  20. A method of variable speed limit control for traffic flow on freeway mainline%高速公路主线可变限速控制方法

    Institute of Scientific and Technical Information of China (English)

    马明辉; 杨庆芳; 梁士栋

    2015-01-01

    The traffic state would become congested at the bottleneck region during peak period, which increase travel time, and decrease efficiency. From time-space traffic characteristics on freeway mainline, macroscopic traffic flow model METANET is modified to describe the traffic flow with VSL control. Furthermore, based on the modified traffic flow models, establish the VSL models at bottleneck region, with the objective of improving traffic efficiency and decreasing travel time. As part of the VSL control algorithm, the proposed VSL control model is implemented at VISSIM simulation platform, the results reveal that the given VSL values according to real time traffic flow conditions can control the vehicles arriving effectively. Therefore, the implement of VSL control can improve traffic efficiency and decrease travel time effectively.%为了解决高流量状态下高速公路主线瓶颈区域交通流运行态势恶劣,导致车辆行程时间增加、道路通行效率降低等问题,从高速公路交通流运行时-空特性角度出发,对宏观交通模型METANET改进,使其能够描述可变限速控制条件下道路交通流运行状态,并以改进模型为基础,提高通行效率和缩短行程时间为目标,构建高速公路主线交通优化控制模型. 实验结果表明:高速公路主线可变限速控制方法能够根据道路交通流量的变化对安全限速值动态设置,实现对危险区车辆到达率的动态控制. 实施高速公路主线可变限速控制方法可有效提高道路通行效率,缩短车辆行程时间.

  1. Hydroclimatological Processes in the Central American Dry Corridor

    Science.gov (United States)

    Hidalgo, H. G.; Duran-Quesada, A. M.; Amador, J. A.; Alfaro, E. J.; Mora, G.

    2015-12-01

    This work studies the hydroclimatological variability and the climatic precursors of drought in the Central American Dry Corridor (CADC), a subregion located in the Pacific coast of Southern Mexico and Central America. Droughts are frequent in the CADC, which is featured by a higher climatological aridity compared to the highlands and Caribbean coast of Central America. The CADC region presents large social vulnerability to hydroclimatological impacts originated from dry conditions, as there is a large part of population that depends on subsistance agriculture. The influence of large-scale climatic precursors such as ENSO, the Caribbean Low-Level Jet (CLLJ), low frequency signals from the Pacific and Caribbean and some intra-seasonal signals such as the MJO are evaluated. Previous work by the authors identified a connection between the CLLJ and CADC precipitation. This connection is more complex than a simple rain-shadow effect, and instead it was suggested that convection at the exit of the jet in the Costa-Rica and Nicaragua Caribbean coasts and consequent subsidence in the Pacific could be playing a role in this connection. During summer, when the CLLJ is stronger than normal, the Inter-Tropical Convergence Zone (located mainly in the Pacific) displaces to a more southern position, and vice-versa, suggesting a connection between these two processes that has not been fully explained yet. The role of the Western Hemisphere Warm Pool also needs more research. All this is important, as it suggest a working hypothesis that during summer, the effect of the Caribbean wind strength may be responsible for the dry climate of the CADC. Another previous analysis by the authors was based on downscaled precipitation and temperature from GCMs and the NCEP/NCAR reanalysis. The data was later used in a hydrological model. Results showed a negative trend in reanalysis' runoff for 1980-2012 in San José (Costa Rica) and Tegucigalpa (Honduras). This highly significant drying trend

  2. Freight corridor performance measurement system: A framework for South Africa

    Directory of Open Access Journals (Sweden)

    Jan H. Havenga

    2016-01-01

    Full Text Available Background: On a national level, South Africa’s freight logistics industry is inefficient. The country ranks 36th out of 40 countries in terms of transport productivity (tonne kilometres as a ratio of gross domestic product, or GDP; the ratio of freight logistics costs to GDP measured 11.1% in 2013, compared to that of developed regions which measures in the order of 9%; and rail tonne-km market share on the two most dense long-distance corridors, namely, GautengDurban and Gauteng-Cape Town, is only 12.8% and 4.4%, respectively, whereas rail is globally acknowledged as a more efficient provider of long-distance freight solutions, given appropriate investments and service commitments.Objectives: A cornerstone of improved national freight logistics performance is the availability of reliable indicators to quantify the efficiency and capacity of the logistics network over the intermediate and long term, thereby enabling an evidence-based policy and investment environment. The objective of this article is to describe the foundation framework (i.e. phase 1 for South Africa’s freight corridor performance measurement system (CPMS. Once populated, the CPMS will be a key generator of indicators to facilitate the systemic management of corridors as a national production factor and thereby contributing to South Africa’s competitiveness.Method: The design of South Africa’s CPMS was informed by desktop research and refined through an extensive stakeholder consultation process. A distinction was made between South Africa’s dedicated bulk corridors and the multi-modal corridors.Results: Facilitating both stakeholder involvement and agreement on key indicators, as well as the eventual development of a system supporting the population, aggregation and dissemination of the CPMS are critical outcomes for the management of corridors as a national production factor. Three overarching corridor indicators were defined, relating to increased throughput, lower

  3. How green are the TEN-T core network corridors?

    DEFF Research Database (Denmark)

    Panagakos, George; Psaraftis, Harilaos N.

    "Green corridors‟ is a concept introduced by the European Commission to enhance the provision of sustainable freight transport logistics services by concentrating freight traffic between major hubs and by relatively long distances. SuperGreen, a Coordination and Support Action aiming at further...... defining this concept, identified the characteristics that distinguish a green corridor from an otherwise efficient one. The main thesis of this paper is that the „core network corridors‟ of the new TEN-T guidelines exhibit all these qualities and the vision of a green corridor network in Europe is close...... to reality. To support this thesis, and in continuation of the work of SuperGreen, the paper examines the proposed new „guidelines‟ for the development of the TEN-T after presenting a brief history of transport network development in Europe....

  4. Bison phylogeography constrains dispersal and viability of the Ice Free Corridor in western Canada.

    Science.gov (United States)

    Heintzman, Peter D; Froese, Duane; Ives, John W; Soares, André E R; Zazula, Grant D; Letts, Brandon; Andrews, Thomas D; Driver, Jonathan C; Hall, Elizabeth; Hare, P Gregory; Jass, Christopher N; MacKay, Glen; Southon, John R; Stiller, Mathias; Woywitka, Robin; Suchard, Marc A; Shapiro, Beth

    2016-07-19

    The Ice Free Corridor has been invoked as a route for Pleistocene human and animal dispersals between eastern Beringia and more southerly areas of North America. Despite the significance of the corridor, there are limited data for when and how this corridor was used. Hypothetical uses of the corridor include: the first expansion of humans from Beringia into the Americas, northward postglacial expansions of fluted point technologies into Beringia, and continued use of the corridor as a contact route between the north and south. Here, we use radiocarbon dates and ancient mitochondrial DNA from late Pleistocene bison fossils to determine the chronology for when the corridor was open and viable for biotic dispersals. The corridor was closed after ∼23,000 until 13,400 calendar years ago (cal y BP), after which we find the first evidence, to our knowledge, that bison used this route to disperse from the south, and by 13,000 y from the north. Our chronology supports a habitable and traversable corridor by at least 13,000 cal y BP, just before the first appearance of Clovis technology in interior North America, and indicates that the corridor would not have been available for significantly earlier southward human dispersal. Following the opening of the corridor, multiple dispersals of human groups between Beringia and interior North America may have continued throughout the latest Pleistocene and early Holocene. Our results highlight the utility of phylogeographic analyses to test hypotheses about paleoecological history and the viability of dispersal routes over time.

  5. Modelling Fine Scale Movement Corridors for the Tricarinate Hill Turtle

    Science.gov (United States)

    Mondal, I.; Kumar, R. S.; Habib, B.; Talukdar, G.

    2016-06-01

    Habitat loss and the destruction of habitat connectivity can lead to species extinction by isolation of population. Identifying important habitat corridors to enhance habitat connectivity is imperative for species conservation by preserving dispersal pattern to maintain genetic diversity. Circuit theory is a novel tool to model habitat connectivity as it considers habitat as an electronic circuit board and species movement as a certain amount of current moving around through different resistors in the circuit. Most studies involving circuit theory have been carried out at small scales on large ranging animals like wolves or pumas, and more recently on tigers. This calls for a study that tests circuit theory at a large scale to model micro-scale habitat connectivity. The present study on a small South-Asian geoemydid, the Tricarinate Hill-turtle (Melanochelys tricarinata), focuses on habitat connectivity at a very fine scale. The Tricarinate has a small body size (carapace length: 127-175 mm) and home range (8000-15000 m2), with very specific habitat requirements and movement patterns. We used very high resolution Worldview satellite data and extensive field observations to derive a model of landscape permeability at 1 : 2,000 scale to suit the target species. Circuit theory was applied to model potential corridors between core habitat patches for the Tricarinate Hill-turtle. The modelled corridors were validated by extensive ground tracking data collected using thread spool technique and found to be functional. Therefore, circuit theory is a promising tool for accurately identifying corridors, to aid in habitat studies of small species.

  6. Comparing the efficiency of transport routes and corridors

    Directory of Open Access Journals (Sweden)

    Liviu Gabriel GHIŢULEASA

    2011-03-01

    Full Text Available In the broader context of the importance granted to accessibility by the European spatial planning policies, comparing the efficiency of European and national transportation routes and corridors constitutes an issue of particular relevance for Romania. In order to resolve it, this paper proposes a methodology based on potential accessibility, determined by the total population served, and the efficiency of the path, by analogy with the least squares method. Both approaches were applied to internal and European routes.

  7. 2010 River Corridor Closure Contractor Revegetation and Mitigation Monitoring Report

    Energy Technology Data Exchange (ETDEWEB)

    C. T. Lindsey, A. L. Johnson

    2010-09-30

    This report documents eh status of revegetation projects and natural resources mitigation efforts conducted for remediated waste sites and other activities associated with CERLA cleanup of National Priorities List waste sites at Hanford. This report contains vegetation monitoring data that were collected in the spring and summer of 2010 from the River Corridor Closure Contract’s revegetation and mitigation areas on the Hanford Site.

  8. Mobile Robot Navigation in a Corridor Using Visual Odometry

    DEFF Research Database (Denmark)

    Bayramoglu, Enis; Andersen, Nils Axel; Poulsen, Niels Kjølstad;

    2009-01-01

    Incorporation of computer vision into mobile robot localization is studied in this work. It includes the generation of localization information from raw images and its fusion with the odometric pose estimation. The technique is then implemented on a small mobile robot operating at a corridor envi...... Kalman filter as a parameter estimator is also applied to estimate odometry parameters. Experimental results are included. The robustness and the precision of the entire system is illustrated by performing simple navigation tasks....

  9. 2011 River Corridor Closure Contractor Revegetation and Mitigation Monitoring Report

    Energy Technology Data Exchange (ETDEWEB)

    West, W. J.; Lucas, J. G.; Gano, K. A.

    2011-11-14

    This report documents the status of revegetation projects and natural resources mitigation efforts conducted for remediated waste sites and other activities associated with the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 cleanup of National Priorities List waste sites at Hanford. This report contains the vegetation monitoring data that was collected in the spring and summer of 2011 from the River Corridor Closure Contractor’s revegetation and mitigation areas on the Hanford Site.

  10. Sacroiliac secure corridor: analysis for safe insertion of iliosacral screws

    Directory of Open Access Journals (Sweden)

    Henrique Alves Cruz

    2013-08-01

    Full Text Available OBJECTIVE: Posterior pelvic lesions, especially of the sacral-iliac joint, have high mortality and morbidity risks. Definitive fixation is necessary for the joint stabilization, and one option is the sacral percutaneous pinning with screws. Proximity to important structures to this region brings risks to the fixation procedure; therefore, it is important to know the tridimensional anatomy of the pelvis posterior region. Deviations of the surgeon's hand of four degrees may target the screws to those structures; dimorphisms of the upper sacrum and a poor lesion reduction may redound in a screw malpositioning. This study is aimed to evaluate the dimensions of a safe surgical corridor for safe sacroiliac screw insertion and relations with age and sex of the patients. METHOD: One hundred randomly selected pelvis CTs of patients with no pelvic diseases, seen at a tertiary care teaching Hospital. Measurements were made by computer and the safest area for screw insertion was calculated by two methods. The results were expressed in mm (not in degrees, in order to be a further surgical reference. RESULTS: There was a significant size difference in the analyzed sacral vertebra, differing on a wider size in men than in women. There was no significant statistical difference between vertebral size and age. By both methods, a safe area for screw insertion could be defined. CONCLUSION: Age does not influence the width of the surgical corridor. The surgeon has a safe corridor considered narrower when inserting screws in a female pelvis than when in a male one. However, as the smallest vertebra found (feminine was considered for statics, it was concluded that this corridor is 20 mm wide in any direction, taking as a reference the centrum of the vertebra.

  11. Regional Studies:External Cognition and Emphasizing Subjectiveness:Taking the Tibetan-Qiang-Yi Corridor as an Example

    Institute of Scientific and Technical Information of China (English)

    Zhang Xi

    2015-01-01

    The“Tibetan -Yi corridor”is a concept constructed by FeiXiaotong and empha-sized by him during the late 1970s and 1980s. In 2011 ,it was replaced with“Tibetan-Qiang-Yi corridor”,a concept which is regarded to conform more to the historical reality. Actually,the earliest research on ethnic corridors largely relied on the earlier research of foreign missionaries who preached their religion in the western part of Si-chuan. It could be said that the missionaries’ re-search on the Qiang opened up the research of the ethnic corridor ,and gradually expanded it to the entire area of western China. Due to the efforts of the missionaries,who received the western formal academic training,there was research that went beyond the study of the feudal dynasties of China to the ethnic minority areas. Since the 1930s,follow-ing the research trends of“the frontier science”( bianjiangxue)and“the frontier political studies”( bianzhengxue),and with China’s local intellectu-al elites’ following up,and especially with the in-vestigations and research findings of the scholars from West China Union University and the Frontier Research Society,the external contours and the knowledge on the internal society,history,cul-ture,and language of the“Tibetan -Qiang -Yi corridor”deepened. These concepts and research results all came from outside the corridor while the society and culture from inside the corridor only provided research data.

  12. Evaluation of the impacts of cooperative adaptive cruise control on reducing rear-end collision risks on freeways.

    Science.gov (United States)

    Li, Ye; Wang, Hao; Wang, Wei; Xing, Lu; Liu, Shanwen; Wei, Xueyan

    2017-01-01

    Although plenty of studies have been conducted recently about the impacts of cooperative adaptive cruise control (CACC) system on traffic efficiency, there are few researches analyzing the safety effects of this advanced driving-assistant system. Thus, the primary objective of this study is to evaluate the impacts of the CACC system on reducing rear-end collision risks on freeways. The CACC model is firstly developed, which is based on the Intelligent Driver Model (IDM). Then, two surrogated safety measures, derived from the time-to-collision (TTC), denoting time exposed time-to-collision (TET) and time integrated time-to-collision (TIT), are introduced for quantifying the collision risks. And the safety effects are analyzed both theoretically and experimentally, by the linear stability analysis and simulations. The theoretical and simulation results conformably indicate that the CACC system brings dramatic benefits for reducing rear-end collision risks (TET and TIT are reduced more than 90%, respectively), when the desired time headway and time delay are set properly. The sensitivity analysis indicates there are few differences among different values of the threshold of TTC and the length of a CACC platoon. The results also show that the safety improvements weaken with the decrease of the penetration rates of CACC on the market and the increase of time delay between platoons. We also evaluate the traffic efficiency of the CACC system with different desired time headway. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. A viscous continuum traffic flow model with consideration of the coupling effect for two-lane freeways

    Institute of Scientific and Technical Information of China (English)

    Sun Di-Hua; Peng Guang-Han

    2009-01-01

    In this paper,the viscous continuum traffic flow model for a single lane is extended to the traffic flow for two-lane freeways. The proposed model is a higher-order continuum model considering the coupling and lane changing effects of the vehicles on two adjacent lanes. It results from integrating the Taylor series expansion of the viscous continuum traffic flow model proposed by Ge (2006 Physics A 371 667) into the multi-lane model presented by Daganzo (1997Transpn. Res. B 31 83). Our proposed model may be used to describe non-anisotropic behaviour because of lane changing in multi-lane traffic. A linear stability analysis is given and the neutral stability condition is obtained. Also,issues related to lane changing,shock waves and rarefaction waves,local clustering and phase transition are investigated through a simulation experiment. The simulation results show that the proposed model is capable of explaining some particular traffic phenomena commonly observable in real world traffic flow.

  14. Modeling signalized intersection safety with corridor-level spatial correlations.

    Science.gov (United States)

    Guo, Feng; Wang, Xuesong; Abdel-Aty, Mohamed A

    2010-01-01

    Intersections in close spatial proximity along a corridor should be considered as correlated due to interacted traffic flows as well as similar road design and environmental characteristics. It is critical to incorporate this spatial correlation for assessing the true safety impacts of risk factors. In this paper, several Bayesian models were developed to model the crash data from 170 signalized intersections in the state of Florida. The safety impacts of risk factors such as geometric design features, traffic control, and traffic flow characteristics were evaluated. The Poisson and Negative Binomial Bayesian models with non-informative priors were fitted but the focus is to incorporate spatial correlations among intersections. Two alternative models were proposed to capture this correlation: (1) a mixed effect model in which the corridor-level correlation is incorporated through a corridor-specific random effect and (2) a conditional autoregressive model in which the magnitude of correlations is determined by spatial distances among intersections. The models were compared using the Deviance Information Criterion. The results indicate that the Poisson spatial model provides the best model fitting. Analysis of the posterior distributions of model parameters indicated that the size of intersection, the traffic conditions by turning movement, and the coordination of signal phase have significant impacts on intersection safety.

  15. Analysis of Potential Energy Corridors Proposed by the Western Electricity Coordinating Council

    Energy Technology Data Exchange (ETDEWEB)

    Kuiper, James A.; Cantwell, Brian J.; Hlava, Kevin J.; Moore, H Robert; Orr, Andrew B.; Zvolanek, Emily A.

    2014-02-24

    This report, Analysis of Potential Energy Corridors Proposed by the Western Electricity Coordinating Council (WECC), was prepared by the Environmental Science Division of Argonne National Laboratory (Argonne). The intent of WECC’s work was to identify planning-level energy corridors that the Department of Energy (DOE) and its affiliates could study in greater detail. Argonne was tasked by DOE to analyze the WECC Proposed Energy Corridors in five topic areas for use in reviewing and revising existing corridors, as well as designating additional energy corridors in the 11 western states. In compliance with Section 368 of the Energy Policy Act of 2005 (EPAct), the Secretaries of Energy, Agriculture, and the Interior (Secretaries) published a Programmatic Environmental Impact Statement in 2008 to address the proposed designation of energy transport corridors on federal lands in the 11 western states. Subsequently, Records of Decision designating the corridors were issued in 2009 by the Bureau of Land Management (BLM) and the U.S. Forest Service (USFS). The 2012 settlement of a lawsuit, brought by The Wilderness Society and others against the United States, which identified environmental concerns for many of the corridors requires, among other things, periodic reviews of the corridors to assess the need for revisions, deletions, or additions. A 2013 Presidential Memorandum requires the Secretaries to undertake a continuing effort to identify and designate energy corridors. The WECC Proposed Energy Corridors and their analyses in this report provide key information for reviewing and revising existing corridors, as well as designating additional energy corridors in the 11 western states. Load centers and generation hubs identified in the WECC analysis, particularly as they reflect renewable energy development, would be useful in reviewing and potentially updating the designated Section 368 corridor network. Argonne used Geographic Information System (GIS) technology to

  16. Landscape corridors can increase invasion by an exotic species and reduce diversity of native species.

    Energy Technology Data Exchange (ETDEWEB)

    Resasco, Julian [University of Florida; et al,

    2014-04-01

    Abstract. Landscape corridors are commonly used to mitigate negative effects of habitat fragmentation, but concerns persist that they may facilitate the spread of invasive species. In a replicated landscape experiment of open habitat, we measured effects of corridors on the invasive fire ant, Solenopsis invicta, and native ants. Fire ants have two social forms: polygyne, which tend to disperse poorly but establish at high densities, and monogyne, which disperse widely but establish at lower densities. In landscapes dominated by polygyne fire ants, fire ant abundance was higher and native ant diversity was lower in habitat patches connected by corridors than in unconnected patches. Conversely, in landscapes dominated by monogyne fire ants, connectivity had no influence on fire ant abundance and native ant diversity. Polygyne fire ants dominated recently created landscapes, suggesting that these corridor effects may be transient. Our results suggest that corridors can facilitate invasion and they highlight the importance of considering species’ traits when assessing corridor utility.

  17. Control On Fluid Flow Properties In Sandstone: Interactions Between Diagenesis Processes And Fracture Corridors

    Science.gov (United States)

    Bossennec, Claire; Géraud, Yves; Moretti, Isabelle; Mattioni, Luca

    2016-04-01

    . Permeabilities measured both on field and in the laboratory show higher values in fractured corridors and close to the fault-core than in the host rock of the damage zone. Samples from both facies, collected close to macroscopic fractures present an increase of permeability (Fa1 permeability from 250 mD up to 1D, Fa2 from 100 mD up to 500mD) associated at microscopic scale with an increase of cracks and fracture density in detrital grains, grain chemical and mechanical compaction, and a decrease of quartz cementation in Fa1 (partly dissolved). Outside of corridors, permeability remains low for both facies (100-130 mD). Smaller contact surfaces between grains, low amounts of cracks and preservation of quartz cement were observed in Fa1 and Fa2. Fractures and cracks create trans-granular spaces and increase connectivity between intergranular spaces, which explains higher ranges of permeability for constant porosities. The increased dissolution of quartz cements observed in high permeable facies can be considered as a result of fluid/rock interaction on a zone restrained to the high permeability corridors. The multiscale analysis of Cleebourg's outcrop shows that sedimentary heritage and structural location seem to constraint and orient fluid-flows, impacting on dissolution and cementation, thus on porosity and permeability increase, and linked petrophysical properties.

  18. Birds of the riparian corridors of Potchefstroom, South Africa / Rindert Wyma

    OpenAIRE

    Wyma, Rindert

    2012-01-01

    A riparian ecosystem is the area between the aquatic and terrestrial setting of a stream, and serves as a corridor and habitat for birds. Several riparian ecosystems are located in urban environments, and three main riparian corridors are located in Potchefstroom. They are the Mooi River, Wasgoed Spruit, and Spitskop Spruit, which encompass a wide range of different vegetation types and anthropogenic factors. Therefore, different habitat types for birds occur along the riparian corridors of P...

  19. Spatio-temporal Analysis of Urban Spatial Interaction in Globalizing China——A Case Study of Beijing-Shanghai Corridor

    Institute of Scientific and Technical Information of China (English)

    WU Wenjie; ZHANG Wenzhong; JIN Fengjun; DENG Yu

    2009-01-01

    This paper aims to explore urban geography with a new perspective. Endowed with the urban geography connotations, an improved data field model is employed to integrate temporal dimension into spatial process of cities in a typical region in this article. Taking the Beijing-Shanghai Corridor including 18 cities as an example, the authors chose the city centricity index (CCI) and the spatial data field model to analyze the evolution process and features of sub-region and urban spatial interaction in this corridor based on the data of 1991, 1996 and 2002. Through the analysis, we found that: 1) with the improvement of the urbanization level and the development of urban economy, the cities' CCI grew, the urban spatial radiative potential enhanced and the radiative range expanded gradually, which reflects the urban spatial interaction's intensity has been increasing greatly; 2) although the spatial interaction intensity among the cities and sub-regions in the Beijing-Shanghai Corridor was growing constantly, the gap of the spatial interaction strength among different cities and sub-regions was widening, and the spatial division between the developed areas and the less developed areas was obvious; and 3) the intensity of the spatial interaction of Beijing, Shanghai and their urban agglomerations was far greater than that in small cities of other parts of the corridor, and it may have a strong drive force on the choice of spatial location of the economic activities.

  20. The evaluation of the development of the Danube-Morava corridor traffic network

    Directory of Open Access Journals (Sweden)

    Vemić Mirčeta R.

    2004-01-01

    Full Text Available Traffic has the primary influence on the development of the Danube-Morava Corridor as a specific natural, geographically determined and stochastic-functional territorial system. The traffic network of roads railway lines and waterways along this corridor is at the very core of the Trans-European Transport Corridor 10, representing its most dynamic, most congested and highest-traffic section. The influence, namely the creative power of traffic, largely depends on the degree of development modernization and maintenance of the network. This work presents the assessment of the development of the Danube-Morava Corridor traffic network.

  1. Monitoring the San Francisco Bay Area Freeway Network Using Probe Vehicles and Random Access Radio Channel

    NARCIS (Netherlands)

    Linnartz, J.P.M.G.; Westerman, M.; Hamerslag, R.

    1994-01-01

    This work was performed as part of the California PATH Program of the University of California, in cooperation with the State of California Business, Transportation, and Housing Agency, Department of Transportation; and the United States Department of Transportation, Federal Highway Administration.

  2. Riparian vegetation dynamics and evapotranspiration in the riparian corridor in the delta of the Colorado River, Mexico.

    Science.gov (United States)

    Nagler, Pamela L; Glenn, Edward P; Hinojosa-Huerta, Osvel; Zamora, Francisco; Howard, Keith

    2008-09-01

    Like other great desert rivers, the Colorado River in the United States and Mexico is highly regulated to provide water for human use. No water is officially allotted to support the natural ecosystems in the delta of the river in Mexico. However, precipitation is inherently variable in this watershed, and from 1981-2004, 15% of the mean annual flow of the Lower Colorado River has entered the riparian corridor below the last diversion point for water in Mexico. These flows include flood releases from US dams and much smaller administrative spills released back to the river from irrigators in the US and Mexico. These flows have germinated new cohorts of native cottonwood and willow trees and have established an active aquatic ecosystem in the riparian corridor in Mexico. We used ground and remote-sensing methods to determine the composition and fractional cover of the vegetation in the riparian corridor, its annual water consumption, and the sources of water that support the ecosystem. The study covered the period 2000-2004, a flood year followed by 4 dry years. The riparian corridor occupies 30,000 ha between flood control levees in Mexico. Annual evapotranspiration (ET), estimated by Moderate Resolution Imaging Spectrometer (MODIS) satellite imagery calibrated against moisture flux tower data, was about 1.1 m yr(-1) and was fairly constant throughout the study period despite a paucity of surface flows 2001-2004. Total ET averaged 3.4 x 10(8)m(3)yr(-1), about 15% of Colorado River water entering Mexico from the US Surface flows could have played only a small part in supporting these high ET losses. We conclude that the riparian ET is supported mainly by the shallow regional aquifer, derived from agricultural return flows, that approaches the surface in the riparian zone. Nevertheless, surface flows are important in germinating cohorts of native trees, in washing salts from the soil and aquifer, and in providing aquatic habitat, thereby enriching the habitat value of

  3. Ontology Model and Application of Emergency Cases for Freeway Traffic Incidents%高速公路交通突发事件案例的本体模型及应用

    Institute of Scientific and Technical Information of China (English)

    李文雄; 闫茂德; 王建伟

    2013-01-01

    Regarding to the requirements for effectively traffic incident management on freeway with the knowledge of previous emergency cases, an ontology based model of freeway traffic emergency cases is constructed. This model provides a unified semantic representation of the development stages of freeway traffic incident as well as the handling processes, among heterogeneous systems deployed in different areas or departments of freeway; and better facilitate the sharing and application of the knowledge of previous emergency cases. To illustrate the usage of this ontology based model, a freeway traffic emergency cases sharing system is sketched, and a typical traffic emergency case is formally described as an ontology instance for joint emergency rescue on freeway.%针对案例驱动的高速公路交通突发事件应急管理的需求,基于本体技术建立了交通突发事件案例的本体模型.该模型可以提供对高速公路交通突发事件的发展过程与应急处置全过程知识的语义一致性描述,屏蔽高速公路不同路段、不同管理部门交通信息管理系统之间的异构性,实现交通突发事件应急案例知识的充分共享和运用.将本体模型应用于高速公路的联动应急救援领域,建立了应急案例共享系统的框架,并以典型的重特大交通事故应急处置为例给出了基于本体模型的应急案例语义描述.

  4. Thick-skinned tectonics closing the Rifian Corridor

    Science.gov (United States)

    Capella, Walter; Matenco, Liviu; Dmitrieva, Evelina; Roest, Wilmer M. J.; Hessels, Suzanne; Hssain, Mohamed; Chakor-Alami, Abdelwahid; Sierro, Francisco J.; Krijgsman, Wout

    2017-07-01

    Tectonic processes in the Gibraltar region are associated with Africa-Iberia convergence and the formation of the Betic-Rif orogenic system. The Late Miocene shortening recorded in the Rif orogen resulted in gradual shallowing and eventual closure of the Rifian Corridor, a narrow marine gateway connecting the Atlantic Ocean with the Mediterranean Sea. This closure is associated with paleoenvironmental changes that ultimately led to the Mediterranean Messinian Salinity Crisis. Here we present a structural analysis based on a combination of field kinematic data and interpretation of reflection seismic lines acquired for petroleum exploration to understand the deformational phases associated with the closure of the Rifian Corridor. We show the succession of three Late Miocene to present day events, an initial thin-skinned nappe thrusting, followed by regional subsidence and continued by thick-skinned contraction. The transition from in sequence thin-skinned tectonics during subduction to thick-skinned contraction during continental collision resulted in significant acceleration of tectonic uplift and associated exhumation. This is related to a change in the regional deformation linked to plate convergence, but possibly also coupled with deep lithospheric or dynamic topography processes. Such a mechanism is also common for other Mediterranean orogens during late stages of slab retreat, where accelerated tectonics resulted in rapid sedimentation and associated basins evolution. We conclude that the thick-skinned contraction in the Rif orogeny initiated in the late Tortonian, has created a cumulative uplift in the order of 1 km, and provided high enough uplift rates to close the Rifian Corridor.

  5. Die Auswirkungen des China-Pakistan Economic Corridor (CPEC)

    OpenAIRE

    Wagner, Christian

    2016-01-01

    "Der China-Pakistan Economic Corridor (CPEC) stellt eine der bislang größten chinesischen Auslandinvestitionen im Rahmen der "One Belt, One Road"-Initiative dar. Im Zuge der Ausgaben in Höhe von rund 46 Milliarden US-Dollar, die in den nächsten Jahren geplant sind, werden sich die chinesisch-pakistanischen Beziehungen weiter vertiefen. Zugleich wird Pakistan für die chinesische Außenpolitik an Bedeutung gewinnen. Der CPEC betrifft aber auch die indisch-pakistanischen Beziehungen. Der Transpor...

  6. Potential corridors and barriers for plague spread in central Asia

    Science.gov (United States)

    2013-01-01

    Background Plague (Yersinia pestis infection) is a vector-borne disease which caused millions of human deaths in the Middle Ages. The hosts of plague are mostly rodents, and the disease is spread by the fleas that feed on them. Currently, the disease still circulates amongst sylvatic rodent populations all over the world, including great gerbil (Rhombomys opimus) populations in Central Asia. Great gerbils are social desert rodents that live in family groups in burrows, which are visible on satellite images. In great gerbil populations an abundance threshold exists, above which plague can spread causing epizootics. The spatial distribution of the host species is thought to influence the plague dynamics, such as the direction of plague spread, however no detailed analysis exists on the possible functional or structural corridors and barriers that are present in this population and landscape. This study aims to fill that gap. Methods Three 20 by 20 km areas with known great gerbil burrow distributions were used to analyse the spatial distribution of the burrows. Object-based image analysis was used to map the landscape at several scales, and was linked to the burrow maps. A novel object-based method was developed – the mean neighbour absolute burrow density difference (MNABDD) – to identify the optimal scale and evaluate the efficacy of using landscape objects as opposed to square cells. Multiple regression using raster maps was used to identify the landscape-ecological variables that explain burrow density best. Functional corridors and barriers were mapped using burrow density thresholds. Cumulative resistance of the burrow distribution to potential disease spread was evaluated using cost distance analysis. A 46-year plague surveillance dataset was used to evaluate whether plague spread was radially symmetric. Results The burrow distribution was found to be non-random and negatively correlated with Greenness, especially in the floodplain areas. Corridors and

  7. Potential corridors and barriers for plague spread in Central Asia.

    Science.gov (United States)

    Wilschut, Liesbeth I; Addink, Elisabeth A; Heesterbeek, Hans; Heier, Lise; Laudisoit, Anne; Begon, Mike; Davis, Stephen; Dubyanskiy, Vladimir M; Burdelov, Leonid A; de Jong, Steven M

    2013-10-31

    Plague (Yersinia pestis infection) is a vector-borne disease which caused millions of human deaths in the Middle Ages. The hosts of plague are mostly rodents, and the disease is spread by the fleas that feed on them. Currently, the disease still circulates amongst sylvatic rodent populations all over the world, including great gerbil (Rhombomys opimus) populations in Central Asia. Great gerbils are social desert rodents that live in family groups in burrows, which are visible on satellite images. In great gerbil populations an abundance threshold exists, above which plague can spread causing epizootics. The spatial distribution of the host species is thought to influence the plague dynamics, such as the direction of plague spread, however no detailed analysis exists on the possible functional or structural corridors and barriers that are present in this population and landscape. This study aims to fill that gap. Three 20 by 20 km areas with known great gerbil burrow distributions were used to analyse the spatial distribution of the burrows. Object-based image analysis was used to map the landscape at several scales, and was linked to the burrow maps. A novel object-based method was developed - the mean neighbour absolute burrow density difference (MNABDD) - to identify the optimal scale and evaluate the efficacy of using landscape objects as opposed to square cells. Multiple regression using raster maps was used to identify the landscape-ecological variables that explain burrow density best. Functional corridors and barriers were mapped using burrow density thresholds. Cumulative resistance of the burrow distribution to potential disease spread was evaluated using cost distance analysis. A 46-year plague surveillance dataset was used to evaluate whether plague spread was radially symmetric. The burrow distribution was found to be non-random and negatively correlated with Greenness, especially in the floodplain areas. Corridors and barriers showed a mostly NWSE

  8. Winter Responses of Forest Birds to Habitat Corridors and Gaps

    Directory of Open Access Journals (Sweden)

    Colleen Cassady St. Clair

    1998-12-01

    Full Text Available Forest fragmentation and habitat loss may disrupt the movement or dispersal of forest-dwelling birds. Despite much interest in the severity of these effects and ways of mitigating them, little is known about actual movement patterns in different habitat types. We studied the movement of wintering resident birds, lured by playbacks of mobbing calls, to compare the willingness of forest birds to travel various distances in continuous forest, along narrow corridors (fencerows, and across gaps in forest cover. We also quantified the willingness of Black-capped Chickadees (Poecile atricapillus to cross gaps when alternative forested detour routes were available. All species were less likely to respond to the calls as distance increased to 200 m, although White-breasted Nuthatches (Sitta carolinensis and Hairy Woodpeckers (Picoides villosus were generally less likely to respond than chickadees and Downy Woodpeckers (P. pubescens. Chickadees were as likely to travel in corridors as in continuous forest, but were less likely to cross gaps as the gap distance increased. The other species were less willing to travel in corridors and gaps relative to forest, and the differences among habitats also increased with distance. For chickadees, gap-crossing decisions in the presence of forested detours varied over the range of distances that we tested, and were primarily influenced by detour efficiency (the length of the shortcut relative to the available detour. Over short distances, birds used forested detours, regardless of their efficiency. As absolute distances increased, birds tended to employ larger shortcuts in the open when detour efficiency was low or initial distance in the open was high, but they limited their distance from the nearest forest edge to 25 m. Thus, chickadees were unwilling to cross gaps of > 50 m when they had forested alternatives, yet they sometimes crossed gaps as large as 200 m when no such choice existed. Our results suggest that

  9. Trade-offs and efficiencies in optimal budget-constrained multispecies corridor networks

    Science.gov (United States)

    Dilkina, Bistra; Houtman, Rachel; Gomes, Carla P.; Montgomery, Claire A.; McKelvey, Kevin; Kendall, Katherine; Graves, Tabitha A.; Bernstein, Richard; Schwartz, Michael K.

    2017-01-01

    Conservation biologists recognize that a system of isolated protected areas will be necessary but insufficient to meet biodiversity objectives. Current approaches to connecting core conservation areas through corridors consider optimal corridor placement based on a single optimization goal: commonly, maximizing the movement for a target species across a network of protected areas. We show that designing corridors for single species based on purely ecological criteria leads to extremely expensive linkages that are suboptimal for multispecies connectivity objectives. Similarly, acquiring the least-expensive linkages leads to ecologically poor solutions. We developed algorithms for optimizing corridors for multispecies use given a specific budget. We applied our approach in western Montana to demonstrate how the solutions may be used to evaluate trade-offs in connectivity for 2 species with different habitat requirements, different core areas, and different conservation values under different budgets. We evaluated corridors that were optimal for each species individually and for both species jointly. Incorporating a budget constraint and jointly optimizing for both species resulted in corridors that were close to the individual species movement-potential optima but with substantial cost savings. Our approach produced corridors that were within 14% and 11% of the best possible corridor connectivity for grizzly bears (Ursus arctos) and wolverines (Gulo gulo), respectively, and saved 75% of the cost. Similarly, joint optimization under a combined budget resulted in improved connectivity for both species relative to splitting the budget in 2 to optimize for each species individually. Our results demonstrate economies of scale and complementarities conservation planners can achieve by optimizing corridor designs for financial costs and for multiple species connectivity jointly. We believe that our approach will facilitate corridor conservation by reducing acquisition costs

  10. THE BALANCE BETWEEN SUPPLY AND DEMAND OF WATER RESOURCES AND THE WATER-SAVING POTENTIAL FOR AGRICULTURE IN THE HEXI CORRIDOR

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The Hexi Corridor is an important base of agriculture development in Northwest China. According to re-cent statistics, there are 65.94 × 108m3 of water resources available in the Hexi Corridor. At present, net consumption indevelopment and utilization is 43.33 x 108m3. Water supply and demand reach a balance on the recent level of produc-tion, but loss of evaporation and evapotranspiration is as much as 25.69 × 108m3. So net use efficiency of water resourcesis 59%. Based on analyzing balance between water and land considering ecological environment at present, there existsthe serious water shortage in the Shiyang River system where irrigation lands have overloaded. There is a comparative bal-ance between supply and demand of water resource in the Heihe River system; and the Sule River system has some sur-plus water to extend irrigation land. Use of agriculture water accounts for 83.3% and ecological forest and grass for6. 9%. The Hexi Corridor still has a great potential for water saving in agriculture production. Water-saving efficiency ofirrigation is about 10% by using such traditional technologies as furrow and border-dike irrigation and small check irriga-tion, and water-saving with plastic film cover and techniques of advanced sprinkler and drip/micro irrigation etc. cansave more than 60% of irrigated water. Incremental irrigation area for water-saving potential in the Hexi Corridor hasbeen estimated as 56% - 197% to original irrigation area. So the second water sources can be developed from water sav-ing agriculture in the Hexi Corridor under Development of the Western Part of China in large scale. This potential can berealized step by step through developing the water-saving measures, improving the ecological condition of oasis agricul-ture, and optimizing allocation of water resources in three river systems.

  11. Methodological Issues and Values Arising from the Construction of a Heritage Corridor Along Chinese Eastern Railway

    Institute of Scientific and Technical Information of China (English)

    Gao; Fei; Shao; Long

    2016-01-01

    The Chinese Eastern Railway(CER),which was designed by Russia in 1898 and constructed later by China,is a typical industrial cultural landscape of the 20 th century that enjoys a high uniqueness and representativeness due to its integrality and systematicness.It sits on a historic site with various kinds of resources,including architecture,railways,and other facilities.As there has been few changes with CER’s route,its resources are,in fact,still serviceable to the current railway system and people living along the route.However,considering the problems,such as lack of maintenance,ignorance of the society,inappropriate renovations,etc.,attention should be paid to CER’s value assessment before any reconstruction decisions are made.Although value assessment plays a very important role in the decision-making and investment-planning process,there is almost no related research on the construction of a heritage corridor along CER.Seeing that value assessment is part of the CER Heritage Corridor construction project and the values act as a reference in understanding CER as a heritage site,this paper aims to put forward a methodological guidance to identify CER’s values,so that its resources will be assessed by using what we call "value typology." In addition,it also tries to promote the tools that can help to evaluate CER’s values.On the basis of a methodological analysis,it finally puts forward some advices to integrating the value assessment into the decision-making process.

  12. 78 FR 73559 - Moose-Wilson Corridor Comprehensive Management Plan, Environmental Impact Statement, Grand Teton...

    Science.gov (United States)

    2013-12-06

    ... National Park Service Moose-Wilson Corridor Comprehensive Management Plan, Environmental Impact Statement... the Moose-Wilson Corridor, Grand Teton National Park, Wyoming. DATES: The National Park Service will...://parkplanning.nps.gov/MooseWilson , at the Grand Teton National Park Headquarters Building, 1 Teton Park...

  13. 14 CFR 93.305 - Flight-free zones and flight corridors.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Flight-free zones and flight corridors. 93... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES Special Flight Rules in the Vicinity of Grand Canyon National Park, AZ § 93.305 Flight-free zones and flight corridors. Except in...

  14. 78 FR 16036 - Service Level Environmental Impact Statement for the Texas Oklahoma Passenger Rail Study Corridor...

    Science.gov (United States)

    2013-03-13

    ... Passenger Rail Study Corridor, South Texas to Oklahoma City AGENCY: Federal Railroad Administration (FRA... Transportation (TxDOT) to study potential new and/or improved high- speed intercity passenger rail service along... Rail Study (Study) also includes preparation of a service development plan for the corridor for each...

  15. 76 FR 63346 - Environmental Impact Statement, Tappan Zee Bridge/I-287 Corridor Project (Rockland and...

    Science.gov (United States)

    2011-10-12

    ... Administration Environmental Impact Statement, Tappan Zee Bridge/I-287 Corridor Project (Rockland and Westchester... preparing an Environmental Impact Statement (EIS) for the proposed Tappan Zee Bridge/I-287 Corridor project... Port Chester, Westchester County, New York including the Tappan Zee Bridge over the Hudson River....

  16. Barchan dune corridors: Field characterization and investigation of control parameters

    Science.gov (United States)

    Elbelrhiti, H.; Andreotti, B.; Claudin, P.

    2008-06-01

    The structure of the barchan field located between Tarfaya and Laayoune (Atlantic Sahara, Morocco) is quantitatively investigated and compared to that in La Pampa de la Joya (Arequipa, Peru). On the basis of field measurements, we show how the volume, the velocity, and the output sand flux of a dune can be computed from the value of its body and horn widths. The dune size distribution is obtained from the analysis of aerial photographs. It shows that these fields are in a statistically homogeneous state along the wind direction and present a "corridor" structure in the transverse direction, in which the dunes have a rather well selected size. Investigating the possible external parameters controlling these corridors, we demonstrate that none among topography, granulometry, wind, and sand flux is relevant. We finally discuss the dynamical processes at work in these fields (collisions and wind fluctuations) and investigate the way they could regulate the size of the dunes. Furthermore, we show that the overall sand flux transported by a dune field is smaller than the maximum transport that could be reached in the absence of dunes, i.e., in saltation over the solid ground.

  17. Influence of buccal corridor dimension on smile esthetics

    Directory of Open Access Journals (Sweden)

    Diana Cunha Nascimento

    2012-10-01

    Full Text Available OBJECTIVE: To assess the influence of buccal corridor width on smile esthetics of male and female, Caucasian and Afro-descendant subjects by means of digitally manipulated photographs, as well as compare assessments of full-face view (FFV and close-up view of the mouth (CUVM images. METHODS: Facial photographs were taken of four adults' smile, two Caucasians and two Afro-descendants of both genders. The resulting images were digitally manipulated with the aim of rendering - from each original smile - three other smiles simulating three different buccal corridor widths, namely, narrow, medium width and wide. The rendered images, 12 of which portraying FFVs and 12 providing CUVMs, were assessed by 60 examiners who rated the attractiveness of each smile by means of a visual analog scale (VAS. The data were treated with ANOVA and Tukey's post test to compare the different buccal corridors, and Student's t test to compare the two image views (FFV and CUVM. RESULTS: Medium width buccal corridors were considered the most attractive in the four individuals investigated, both in the assessment of FFVs and CUVMs (p 0.05. Furthermore, no statistically significant difference was found between the analyses of FFVs and CUVMs (p > 0.05. CONCLUSION: The buccal corridor exercised a remarkable influence on smile esthetics, with the medium width group being rated as the most attractive. No influence was exerted by the individuals' face, ethnicity or gender.OBJETIVO: avaliar a influência do corredor bucal na estética de sorrisos femininos e masculinos, de leucodermas e melanodermas, por meio de fotografias manipuladas, bem como comparar essa avaliação numa vista facial completa e numa vista aproximada da boca. MÉTODOS: foram realizadas fotografias faciais do sorriso de quatro indivíduos adultos, sendo dois leucodermas e dois melanodermas, de ambos os sexos. As imagens geradas foram manipuladas a fim de produzir, a partir de cada sorriso original, três outros

  18. Fruit Plants Species along Corridor in Kopendukuh Village as a Resource for Rural Tourism Development

    Directory of Open Access Journals (Sweden)

    Widya Kristiyanti Putri

    2015-02-01

    Full Text Available This research aims to identify fruit plants species which is potential for tourism attraction, spatially describes fruit plants distribution and identify local people’s response for fruit plants as tourims attraction in Kopendukuh village, Banyuwangi. Survey was done along the villages corridors. The fruit plant species along corridors was identified and mapped using GPS. Furthermore, semi-structural interview was used to gain informations of local people response about fruit plants as tourism attraction. There were about 18 species and 162 individuals were found along corridor of Kopendukuh village. Fruit plants always found in local home gardens along rural corridor. Local peoples argue that fruit planst s important for numerous purposes. Local people support tourism development in rural area which based on the fruit plants richness (i.e. agrotourism. Keywords: fruit plants, mapping, corridor, rural tourism.

  19. PM10 emission factors for non-exhaust particles generated by road traffic in an urban street canyon and along a freeway in Switzerland

    Science.gov (United States)

    Bukowiecki, N.; Lienemann, P.; Hill, M.; Furger, M.; Richard, A.; Amato, F.; Prévôt, A. S. H.; Baltensperger, U.; Buchmann, B.; Gehrig, R.

    2010-06-01

    Recent studies have shown clear contributions of non-exhaust emissions to the traffic related PM10 load of the ambient air. These emissions consist of particles produced by abrasion from brakes, road wear, tire wear, as well as vehicle induced resuspension of deposited road dust. The main scope of the presented work was to identify and quantify the non-exhaust fraction of traffic related PM10 for two roadside locations in Switzerland with different traffic regimes. The two investigated locations, an urban street canyon with heavily congested traffic and an interurban freeway, are considered as being typical for Central Europe. Mass-relevant contributions from abrasion particles and resuspended road dust mainly originated from particles in the size range 1-10 μm. The results showed a major influence of vehicle induced resuspension of road dust. In the street canyon, the traffic related PM10 emissions (LDV: 24 ± 8 mg km -1 vehicle -1, HDV: 498 ± 86 mg km -1 vehicle -1) were assigned to 21% brake wear, 38% resuspended road dust and 41% exhaust emissions. Along the freeway (LDV: 50 ± 13 mg km -1 vehicle -1, HDV: 288 ± 72 mg km -1 vehicle -1), respective contributions were 3% brake wear, 56% resuspended road dust and 41% exhaust emissions. There was no indication for relevant contributions from tire wear and abrasion from undamaged pavements.

  20. 78 FR 43226 - Going-to-the-Sun Road Corridor Management Plan, Environmental Impact Statement, Glacier National...

    Science.gov (United States)

    2013-07-19

    ... National Park Service Going-to-the-Sun Road Corridor Management Plan, Environmental Impact Statement... Environmental Impact Statement for the Going-to-the-Sun Road Corridor Management Plan for Glacier National Park...-to-the Sun Road (GTSR) corridor. DATES: The National Park Service will accept comments from...

  1. ORNL Trusted Corridors Project: Watts Bar Dam Inland Waterway Project

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Randy M [ORNL; Gross, Ian G [ORNL; Smith, Cyrus M [ORNL; Hill, David E [ORNL

    2011-11-01

    Radiation has existed everywhere in the environment since the Earth's formation - in rocks, soil, water, and plants. The mining and processing of naturally occurring radioactive materials for use in medicine, power generation, consumer products, and industry inevitably generate emissions and waste. Radiological measuring devices have been used by industry for years to measure for radiation in undesired locations or simply identify radioactive materials. Since the terrorist attacks on the United States on 9-11-01 these radiation measuring devices have proliferated in many places in our nation's commerce system. DOE, TVA, the Army Corps and ORNL collaborated to test the usefulness of these devices in our nation's waterway system on this project. The purpose of the Watts Bar Dam ORNL Trusted Corridors project was to investigate the security, safety and enforcement needs of local, state and federal government entities for state-of-the-art sensor monitoring in regards to illegal cargo including utilization of the existing infrastructure. TVA's inland waterways lock system is a recognized and accepted infrastructure by the commercial carrier industry. Safety Monitoring activities included tow boat operators, commercial barges and vessels, recreational watercraft and their cargo, identification of unsafe vessels and carriers, and, monitoring of domestic and foreign commercial vessels and cargo identification. Safety Enforcement activities included cargo safety, tracking, identification of hazardous materials, waterway safety regulations, and hazardous materials regulations. Homeland Security and Law Enforcement Applications included Radiological Dispersive Devices (RDD) identification, identification of unsafe or illicit transport of hazardous materials including chemicals and radiological materials, and screening for shipments of illicit drugs. In the Fall of 2005 the SensorNet funding for the project expired. After several unsuccessful attempts to

  2. Ecological and Recreational Corridor Bogotá Mountain Reserve

    Directory of Open Access Journals (Sweden)

    Diana Wiesner

    2013-01-01

    Full Text Available Bogotá the capital of the Republic of Colombia is a tropical highland city located at 2650 m above sea level, the 25th largest city of the world and among the large, one of the highest. A proposal for integration of components of ecological networks in the Oriental Hills of Bogotá, along a gradient from wild to built nature. Name as The Bogotá Ecological and Recreational Corridor (C.E.R. is based on three strategies: first a social being the largest border agreement with 53 km, along the entire eastern limit of the city. Second the biophysical which involves restoration of ecosystem, and third the socio-spatial which includes infrastructure for making an open air museum for integration and urban limit. The ultimate aim of the approach is to contribute as a pilot proposal in biodiversity managment and cultural transformation in ecological issues for the inhabitants.

  3. The role of green corridors for wildlife conservation in urban landscape: A literature review

    Science.gov (United States)

    Aziz, H. A.; Rasidi, M. H.

    2014-02-01

    Green corridors are an attempt to mitigate negative effects of the built environment of cities and towns. The corridors act as conservation for rapidly extreme intervention and development of the urban environment. Most importantly, it enables dispersal movement of animals within city areas. Issues relate to wildlife conservation in urban areas has been studied for many years and thus, the research makes a review for how the green corridors contribute to the conservation of urban wildlife. This study reviews groups of articles in disciplines of urban landscape planning and biology conservation to discuss the relationship between elements of green corridors and urban wildlife dispersal movement behaviour in Malaysian context. Accordingly, this research is purposely studied to give understanding on how green corridors contribute to the animals' ability of moving and dispersing within the built-up areas. In advance, it is found that there are three factors contribute to the capability of colonization among urban wildlife which are individual, physical and social factor. Green corridor has been defined as one of the physical factor that influence urban wildlife behaviour movement. Consequently, safety area indicating to animals species for traversing in any time such as at night can be defined as the primary potential corridor.

  4. Carbon stock corridors to mitigate climate change and promote biodiversity in the tropics

    Science.gov (United States)

    Jantz, Patrick; Goetz, Scott; Laporte, Nadine

    2014-02-01

    A key issue in global conservation is how biodiversity co-benefits can be incorporated into land use and climate change mitigation activities, particularly those being negotiated under the United Nations to reduce emissions from tropical deforestation and forest degradation. Protected areas have been the dominant strategy for tropical forest conservation and they have increased substantially in recent decades. Avoiding deforestation by preserving carbon stored in vegetation between protected areas provides an opportunity to mitigate the effects of land use and climate change on biodiversity by maintaining habitat connectivity across landscapes. Here we use a high-resolution data set of vegetation carbon stock to map corridors traversing areas of highest biomass between protected areas in the tropics. The derived corridors contain 15% of the total unprotected aboveground carbon in the tropical region. A large number of corridors have carbon densities that approach or exceed those of the protected areas they connect, suggesting these are suitable areas for achieving both habitat connectivity and climate change mitigation benefits. To further illustrate how economic and biological information can be used for corridor prioritization on a regional scale, we conducted a multicriteria analysis of corridors in the Legal Amazon, identifying corridors with high carbon, high species richness and endemism, and low economic opportunity costs. We also assessed the vulnerability of corridors to future deforestation threat.

  5. Northeast Asian Energy Corridor Initiative for Regional Collaboration

    Directory of Open Access Journals (Sweden)

    Paik Hoon

    2012-12-01

    Full Text Available For historical and political reasons, South Korea (hereafter Korea, Japan and China have not achieved much progress in regional energy cooperation for decades. However, the rising importance of Northeast Asia (NEA in the world energy sphere, especially in the global oil market, is providing an opportunity to create an integrated oil market in the region. This study suggests the Northeast Asian Energy Corridor (NEAEC Initiative as an effective conduit for raising the possibility of the Northeast Asian oil hub project. The NEAEC Initiative combines the model of Europe's Amsterdam-Rotterdam-Antwerp (ARA with Singapore's AsiaClear as a form of financial collaboration. The study suggests that an elFor historical and political reasons, South Korea (hereafter Korea, Japan and China have not achieved much progress in regional energy cooperation for decades. However, the rising importance of Northeast Asia (NEA in the world energy sphere, especially in the global oil market, is providing an opportunity to create an integrated oil market in the region. This study suggests the Northeast Asian Energy Corridor (NEAEC Initiative as an effective conduit for raising the possibility of the Northeast Asian oil hub project. The NEAEC Initiative combines the model of Europe's Amsterdam-Rotterdam-Antwerp (ARA with Singapore’s AsiaClear as a form of financial collaboration. The study suggests that an electronically integrated Over-the-Counter (OTC market clearing mechanism accompanied by other key financial instruments among Korea, Japan and China can be an effective means for promoting financial collaboration in the region.

  6. Supply Chain Strategies for the International Interoceanic Mazatlan-Houston Logistic Corridor

    Directory of Open Access Journals (Sweden)

    G. de la O

    2014-08-01

    Full Text Available Describe the interoceanic Mazatlan-Houston Logistic Corridor (MHLC as an alternative route to create sustainable competitive advantages for Mexican, USA, and international firms competing in an international marketplace. Taking into account the competitive advantages of utilizing this corridor for international trade, we analyze supply chain strategies for Mexican and international companies demanding economical logistic solutions in this region. It was found that the MHLC benefits efficient industry segments with demand well known in advance. It was also found that the potential of both inbound and outbound container traffic to the Asia-Pacific marketplace along this international commerce corridor fluctuates between 39,000 and 761,000 TEU's.

  7. The natural and social history of the indigenous lands and protected areas corridor of the Xingu River basin.

    Science.gov (United States)

    Schwartzman, Stephan; Boas, André Villas; Ono, Katia Yukari; Fonseca, Marisa Gesteira; Doblas, Juan; Zimmerman, Barbara; Junqueira, Paulo; Jerozolimski, Adriano; Salazar, Marcelo; Junqueira, Rodrigo Prates; Torres, Maurício

    2013-06-05

    The 280,000 km² Xingu indigenous lands and protected areas (ILPAs) corridor, inhabited by 24 indigenous peoples and about 215 riverine (ribeirinho) families, lies across active agriculture frontiers in some of the historically highest-deforestation regions of the Amazon. Much of the Xingu is anthropogenic landscape, densely inhabited and managed by indigenous populations over the past millennium. Indigenous and riverine peoples' historical management and use of these landscapes have enabled their long-term occupation and ultimately their protection. The corridor vividly demonstrates how ILPAs halt deforestation and why they may account for a large part of the 70 per cent reduction in Amazon deforestation below the 1996-2005 average since 2005. However, ongoing and planned dams, road paving, logging and mining, together with increasing demand for agricultural commodities, continued degradation of upper headwaters outside ILPA borders and climate change impacts may render these gains ephemeral. Local peoples will need new, bottom-up, forms of governance to gain recognition for the high social and biological diversity of these territories in development policy and planning, and finance commensurate with the value of their ecosystem services. Indigenous groups' reports of changing fire and rainfall regimes may themselves evidence climate change impacts, a new and serious threat.

  8. Following Phenomenon and Air Freeway Flow Model%空中高速路交通流的跟驰现象及流量模型

    Institute of Scientific and Technical Information of China (English)

    王莉莉; 张新瑜; 张兆宁

    2012-01-01

    Air freeways connecting long-distance city-pairs with heavy traffic flow in the next generation aviation transportation system ( NGATS) are characterized by monolayer route with single direction, no crossover, aircraft performance limitation, and high density of operation. In order to study the traffic flow operation on the air freeways, a microscopic aircraft-following model for single-layer route of air freeways was established using the car-following theory, based on the civil aviation operation rules of NGATS. Through analysis of the relationship between air traffic flow and density, the model was then extended to a macroscopic traffic flow model for air freeways. The macroscopic model can be used for air route flow optimization, safety analysis, and capacity evaluation. Simulation results of the microscopic aircraft-following model show that the aircraft-following response of a posterior aircraft intensifies when the separation distance from its anterior aircraft is nearer, the speed of flight in the route is faster, or the respond intensity of the posterior aircraft is weaker. Simulation results of the macroscopic air traffic flow model show that the air traffic flow variation is more remarkable when the aircraft separation distance is smaller or the initial velocity is larger.%为研究下一代航空运输系统空中高速路的流量模型,针对连接远程、繁忙航线城市对的空中高速路具有航路单向、无交叉、有性能限制、高密度运行的特点,以下一代航空运输系统的运行规则为基础,基于跟驰理论,对单层航路建立了空中高速路交通流微观跟驰模型.通过对空中交通流量密度关系的分析,扩展出空中交通流的宏观流量模型,该模型可用于航路流量优化、安全分析和航路容量评估等.计算结果表明:由微观跟驰模型得出,运行于空中高速路上的航空器间隔越小、速度越快、后机反应强度越小,后机相对于前机的跟驰反应

  9. Mitigating and Tracking Black Carbon Exposure at Schools in the Mountain View Corridor of Salt Lake City

    Science.gov (United States)

    Roberts, P. T.; Brown, S. G.; Vaughn, D.; DeWinter, J. L.

    2015-12-01

    Black carbon (BC) is a short lived climate forcer and is associated with human health effects. We measured BC inside and outside at four schools in Salt Lake City during two studies in 2011-2014. In addition, PM2.5 was measured indoor and outdoor at one school, and gaseous air toxics outdoor at one school. The schools are within 500 m of a planned major freeway, and two of them will adjoin the freeway. The objectives included determining the outdoor and indoor concentrations of BC, the likely sources of BC, and once the freeway is built, the change in ambient BC at the schools. We determined the current state of air quality outdoors at these schools, to provide baseline data for comparison when the major freeway is operational, and indoors as a baseline before installing improved filtration to reduce BC in classrooms. Using MATES IV cancer risk values, we found that diesel particulate matter, as indicated by ambient, outdoor BC measurements, was responsible for 84% of the cancer risk at the schools. The HVAC system was moderately effective at filtrating PM mass (73% reduction), but very poor at filtering BC (7%-34% reduction), indicating that air toxics risk is similar indoors and outdoors. Improved filtration devices could potentially mitigate this risk, and improved filtration systems have been recommended for the schools. Lastly, we used the difference in absorption at two Aethalometer channels to determine that the majority of BC (> 90%) during the spring through fall is from fossil fuel emissions.

  10. EAARL-B Topography-Big Thicket National Preserve: Menard Creek Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the Menard Corridor Unit of Big Thicket National Preserve in Texas was produced from remotely...

  11. Water Resource Inventory and Assessment (WRIA) - Iowa Corridor Project Area (Port Louisa NWR)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Water Resource Inventory and Assessment (WRIA) Summary Report for Iowa Corridor Project Area describes current hydrologic information, provides an assessment of...

  12. Taos Smart Growth Implementation Assistance: Concepts for the Paseo del Pueblo Sur Corridor

    Science.gov (United States)

    This report describes a technical assistance project with Taos, NM, to help make development along State Highway 68, the Paseo del Pueblo Sur commercial corridor, economically stronger and more attractive.

  13. Mark Twain National Wildlife Refuge Iowa River Corridor Project [Land Status Map: Sheet 3 of 3

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This map was produced by the Division of Realty to depict landownership at Mark Twain National Wildlife Refuge Iowa River Corridor Project. It was generated from...

  14. Mark Twain National Wildlife Refuge Iowa River Corridor Project [Land Status Map: Sheet 2 of 3

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This map was produced by the Division of Realty to depict landownership at Mark Twain National Wildlife Refuge Iowa River Corridor Project. It was generated from...

  15. Mark Twain National Wildlife Refuge Iowa River Corridor Project [Land Status Map: Sheet 1 of 3

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This map was produced by the Division of Realty to depict landownership at Mark Twain National Wildlife Refuge Iowa River Corridor Project. It was generated from...

  16. EAARL-B Topography-Big Thicket National Preserve: Big Sandy Creek Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the Big Sandy Creek Corridor Unit of Big Thicket National Preserve in Texas was produced from...

  17. EAARL-B Topography-Big Thicket National Preserve: Lower Neches River Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first-surface topography Digital Surface Model (DSM) mosaic for the Lower Neches River Corridor Unit of Big Thicket National Preserve in Texas was produced from...

  18. Sensitivity of Occupant Response Subject to Prescribed Corridors for Impact Testing

    Directory of Open Access Journals (Sweden)

    J.R. Crandall

    1996-01-01

    Full Text Available A technology to study the sensitivity of impact responses to prescribed test conditions is presented. Motor vehicle impacts are used to illustrate the principles of this sensitivity technology. Impact conditions are regulated by specifying either a corridor for the acceleration time history or other test parameters such as velocity change, static crush distance, and pulse duration. By combining a time domain constrained optimization method and a multirigid body dynamics simulator, the upper and lower bounds of occupant responses subject to the regulated corridors were obtained. It was found that these prescribed corridors may be either so wide as to allow extreme variations in occupant response or so narrow that they are physically unrealizable in the laboratory test environment. A new corridor based on specifications for the test parameters of acceleration, velocity. crush distance, and duration for frontal vehicle impacts is given.

  19. EAARL-B Topography-Big Thicket National Preserve: Big Sandy Creek Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the Big Sandy Creek Corridor Unit of Big Thicket National Preserve in Texas was produced from...

  20. A Simulation Testbed for Dynamic Air Corridors within the Next Generation Air Transportation System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The key innovation in this effort is the development of a simulation testbed for identifying dynamic air corridors that can increase aircraft throughput in and...

  1. EAARL-B Topography-Big Thicket National Preserve: Village Creek Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the Village Creek Corridor Unit of Big Thicket National Preserve in Texas was produced from remotely...

  2. 2006 Multibeam Mapping of along-shelf corridor, between Madison-Swanson and Steamboat Lumps Florida

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This disk or set of disks contain high-resolution multibeam and backscatter maps of a long thin corridor at the shelf edge near he 74-m isobath spanning from...

  3. EAARL-B Topography-Big Thicket National Preserve: Menard Creek Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the Menard Corridor Unit of Big Thicket National Preserve in Texas was produced from remotely...

  4. EAARL-B Topography-Big Thicket National Preserve: Lower Neches River Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first-surface topography Digital Surface Model (DSM) mosaic for the Lower Neches River Corridor Unit of Big Thicket National Preserve in Texas was produced from...

  5. EAARL-B Topography-Big Thicket National Preserve: Menard Creek Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first-surface topography Digital Surface Model (DSM) mosaic for the Menard Corridor Unit of Big Thicket National Preserve in Texas was produced from remotely...

  6. EAARL-B Topography-Big Thicket National Preserve: Big Sandy Creek Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first-surface topography Digital Elevation Model (DEM) mosaic for the Big Sandy Creek Corridor Unit of Big Thicket National Preserve in Texas was produced from...

  7. Time-averaged currents in the Northeast Corridor Reserve during November 2013.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 2D numerical model, CMS-Flow, was implemented for the Northeast Corridor Reserve (NECR) using a telescoping grid. Tide and wind forcing was provided to the model...

  8. Empowerment Zones and Enterprise Districts - MDC_TargetUrbanAreaCorridor

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — A polygon feature class of Miami-Dade County, Targeted Urban Area Corridors. This coverage was created for the Office of Community & Economic Development (OCED)...

  9. EAARL-B Topography-Big Thicket National Preserve: Lower Neches River Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the Lower Neches River Corridor Unit of Big Thicket National Preserve in Texas was produced from...

  10. EAARL-B Topography-Big Thicket National Preserve: Menard Creek Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first-surface topography Digital Surface Model (DSM) mosaic for the Menard Corridor Unit of Big Thicket National Preserve in Texas was produced from remotely...

  11. EAARL-B Topography-Big Thicket National Preserve: Big Sandy Creek Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first-surface topography Digital Elevation Model (DEM) mosaic for the Big Sandy Creek Corridor Unit of Big Thicket National Preserve in Texas was produced from...

  12. EAARL-B Topography—Big Thicket National Preserve: Village Creek Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first-surface topography Digital Surface Model (DSM) mosaic for the Village Creek Corridor Unit of Big Thicket National Preserve in Texas was produced from...

  13. Wild felid species richness affected by a corridor in the Lacandona forest, Mexico

    Directory of Open Access Journals (Sweden)

    Gil–Fernández, M.

    2017-02-01

    Full Text Available Wild felids are one of the most vulnerable species due to habitat loss caused by fragmentation of ecosystems. We analyzed the effect of a structural corridor, defined as a strip of vegetation connecting two habitat patches, on the richness and habitat occupancy of felids on three sites in Marqués de Comillas, Chiapas, one with two isolated forest patches, the second with a structural corridor, and the third inside the Montes Azules Biosphere Reserve. We found only two species (L. pardalis and H. yagouaroundi in the isolated forest patches, five species in the structural corridor, and four species inside the Reserve. The corridor did not significantly affect occupancy, but due to the low detection rates, further investigation is needed to rule out differences. Our results highlight the need to manage habitat connectivity in the remaining forests in order to preserve the felid community of Marqués de Comillas, Chiapas, México.

  14. EAARL-B Topography-Big Thicket National Preserve: Lower Neches River Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the Lower Neches River Corridor Unit of Big Thicket National Preserve in Texas was produced from...

  15. A Simultaneous Confidence Corridor for Varying Coefficient Regression with Sparse Functional Data

    OpenAIRE

    Gu, Lijie; Li WANG; Härdle, Wolfgang Karl; Yang, Lijian

    2014-01-01

    We consider a varying coefficient regression model for sparse functional data, with time varying response variable depending linearly on some time independent covariates with coefficients as functions of time dependent covariates. Based on spline smoothing, we propose data driven simultaneous confidence corridors for the coefficient functions with asymptotically correct confidence level. Such confidence corridors are useful benchmarks for statistical inference on the global shapes of coeffici...

  16. The effects of the China-Pakistan Economic Corridor on India-Pakistan relations

    OpenAIRE

    Wagner, Christian

    2016-01-01

    The China-Pakistan Economic Corridor (CPEC) constitutes one of the largest foreign investments China has made in the framework of the "One Belt, One Road" initiative. The expenditures planned for the coming years in the amount of approximately $46 billion will further intensify relations between China and Pakistan. At the same time, Pakistan will assume a more prominent role in China's foreign policy. But CPEC also affects relations between India and Pakistan. The transport corridor between P...

  17. Rise of Regional Logistics Hubs in Global Trade : Role of Arctic Corridor in Finland

    OpenAIRE

    Buyle, Christophe

    2015-01-01

    The proposed research concerns the engagement of the Finnish transport network into national, regional, European and global supply chains. The author was interested in studying the role of new transport corridors in trade reactivity and changes in market trends. The main target of the thesis is to understand the role of the Arctic Corridor on the implementation of Finnish development strategies. The mineral industry in Finnish Lapland and the extraction of natural resources in the Barent...

  18. Corridor connecting giant panda habitats from north to south in the Min Mountains, Sichuan, China.

    Science.gov (United States)

    Yin, Kaipu; Xie, Yan; Wu, Ning

    2006-12-01

    The giant panda faces severe threats from habitat fragmentation and isolation. Currently, giant panda populations have been fragmented into 30 habitat patches. The disappearance of isolated small populations and studies on the genetic diversity of various populations have shown that small isolated panda populations are at a high risk of dying out completely. Habitat fragmentation has seriously impaired the ability of the giant panda to resist climate changes and other natural disasters, such as large-scale, synchronous bamboo blooming. The Min Mountains have the largest population of pandas in China, numbering 581 individuals and accounting for 52% of the total (1114) in China. Geographic isolation means that giant pandas in the Min Mountains are divided into two populations (population A in the north and population B in the south). Population B, which had only 42 individuals in 1989, is severely threatened by high-density human populations and the loss of genetic diversity. However, we have identified an important corridor connecting the two populations. This paper explains the importance and the feasibility of reestablishing this corridor. Due to the special geographic locations of these two populations (two rivers block the migration of giant pandas between south and north), the corridor is the only passage for giant pandas in the region. Recent studies have also shown an increase of giant panda activity in the area of the corridor. However, vegetation in the corridor has been severely degraded. Bamboo forest must be restored in this area to provide food for the pandas during migration. The effects of human activities must be reduced in order to maintain panda habitat. We believe that a restored corridor will be of great benefit to the survival of giant pandas in the Min Mountains, especially for population B. Successful re-establishment of a corridor will be a valuable model for corridor construction in the future.

  19. Factors affecting buccal corridor space in Angle′s Class II Division 1 malocclusion

    Directory of Open Access Journals (Sweden)

    Rashmi Bhat

    2014-01-01

    Full Text Available Background and Objectives: Buccal corridor space has been thought of primarily in terms of maxillary width, but there is also evidence that they are heavily influenced by the antero-posterior position of maxilla. The present study was undertaken with an aim of evaluating and comparing the dental and skeletal factors related to buccal corridor space in individuals having Class I and Class II Division 1 malocclusions. Materials and Methods: A total of 80 subjects of which 40 were males and 40 were females in the age group of 20-30 years were selected as per inclusion criteria and were grouped as Group I having Class I malocclusion and as Group II having Class II malocclusions based on angle ANB. 12 linear and 2 angular cephalometric measurements and 4 study cast measurements were used to correlate with the buccal corridor linear ratio (BCLR, calculated on smile photograph using the Adobe Photoshop 7.0 software (Adobe Systems Inc., San Jose, California, USA. The data obtained was statistically evaluated using independent t-test and multiple linear regression analysis. Result: Buccal corridor space is larger in individuals with Class II Division 1 malocclusion when compared with individuals with Class I malocclusions. There exists a significant difference in buccal corridor space between males and females. Conclusion: The present study helps in establishing the correlation between certain factors and the amount of buccal corridor space in individuals having skeletal Class II pattern.

  20. A Multi-Sensor Remote Sensing Approach for Railway Corridor Ground Hazard Management

    Science.gov (United States)

    Kromer, Ryan; Hutchinson, Jean; Lato, Matt; Gauthier, Dave; Edwards, Tom

    2015-04-01

    Characterizing and monitoring ground hazard processes is a difficult endeavor along mountainous transportation corridors. This is primarily due to the quantity of hazard sites, complex topography, limited and sometimes hazardous access to sites, and obstructed views. The current hazard assessment approach for Canadian railways partly relies on the ability of inspection employees to assess hazard from track level, which isn't practical in complex slope environments. Various remote sensing sensors, implemented on numerous platforms have the potential to be used in these environments. They are frequently found to be complementary in their use, however, an optimum combination of these approaches has not yet been found for an operational rail setting. In this study, we investigate various cases where remote sensing technologies have been used to characterize and monitor ground hazards along railway corridors across the Canadian network, in order to better understand failure mechanisms, identify hazard source zones and to provide early warning. Since early 2012, a series of high resolution gigapixel images, Terrestrial Laser Scanning (TLS), Aerial laser scanning (ALS), ground based photogrammetry, oblique aerial photogrammetry (from helicopter and Unmanned Aerial Vehicle (UAV) platforms), have been collected at ground hazard sites throughout the Canadian rail network. On a network level scale, comparison of sequential ALS scanning data has been found to be an ideal methodology for observing large-scale change and prioritizing high hazard sites for more detailed monitoring with terrestrial methods. The combination of TLS and high resolution gigapixel imagery at various temporal scales has allowed for a detailed characterization of the hazard level posed by the slopes, the identification of the main failure modes, an analysis of hazard activity, and the observation failure precursors such as deformation, rockfall and tension crack opening. At sites not feasible for ground

  1. Transport corridors and settlements in a region. Linking settlements to public transport

    Directory of Open Access Journals (Sweden)

    Mojca Šašek Divjak

    2004-01-01

    Full Text Available The focus of the article is conditioning settlement to public transport on the regional and urban level. Similar to occurrences in Western Europe even in Slovenia strong settlement pressures and issues tied to development of suburbanisation are emerging in wider hinterlands of larger cities. In regional centres, where strong transport flows with frequent congestion happen, public transport should be the backbone of the transport system. It is important for consolidation of larger gravitation areas, especially conurbations. We can nevertheless establish that parallel to increasing use of private cars, the use of public transport is decreasing. Thus the present condition demands improvements of transport systems and suitable settlement density in conjunction with development of public transport. This can be achieved only by synergetic linking of public transport development and physical planning in a sustainable settlement system. In the Ljubljana functional region we specifically dealt with links between settlement and the regional public transport system, above all the proposed regional light-railway and tram system in the strict urban area. The decentralised denser settlement model is presented. Based on the study concerning settlement development in the railway corridors we proposed potential possibilities for denser settlement in the immediate areas of suburban railway stations in the northern part of the region, from Črnuče to Kamnik.

  2. Small mammal populations in a restored stream corridor

    Energy Technology Data Exchange (ETDEWEB)

    Wike, L.D.

    2000-03-13

    An opportunity to study the response of a small mammal community to restoration of a riparian wetland was provided by the Pen Branch project at the Savannah River Site (SRS). Live trapping of small mammals was conducted on six transects at Pen Branch in 1996 and 1998 and at three transects at Meyer's Branch, an unimpacted stream at SRS, in 1997 and 1998. Distributions of rates of capture of the four most common species were both spatially and temporally uneven. Kruskal-Wallis one-way analysis of variance found no significant differences in the relationship of capture rates between species and between treatment and both the within-stream control and Meyers Branch. Habitat use and movement within stream corridors appears to be dependent primarily on species, with age and sex perhaps contributing to preference and distance moved. The lack of differences in capture rates related to transect or treatment may be due to the close proximity of sample transects relative to the movement potential of the species sampled.

  3. Renewable Energy Zones for the Africa Clean Energy Corridor

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Grace C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Deshmukh, Ranjit [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Ndhlukula, Kudakwashe [International Renewable Energy Agency (IRENA), Abu Dhabi (United Arab Emirates); Radojicic, Tijana [International Renewable Energy Agency (IRENA), Abu Dhabi (United Arab Emirates); Reilly, Jessica [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States)

    2015-07-01

    Multi-criteria Analysis for Planning Renewable Energy (MapRE) is a study approach developed by the Lawrence Berkeley National Laboratory with the support of the International Renewable Energy Agency (IRENA). The approach combines geospatial, statistical, energy engineering, and economic methods to comprehensively identify and value high-quality wind, solar PV, and solar CSP resources for grid integration based on techno-economic criteria, generation profiles (for wind), and socio-environmental impacts. The Renewable Energy Zones for the Africa Clean Energy Corridor study sought to identify and comprehensively value high-quality wind, solar photovoltaic (PV), and concentrating solar power (CSP) resources in 21 countries in the East and Southern Africa Power Pools to support the prioritization of areas for development through a multi-criteria planning process. These countries include Angola, Botswana, Burundi, Djibouti, Democratic Republic of Congo, Egypt, Ethiopia, Kenya, Lesotho, Libya, Malawi, Mozambique, Namibia, Rwanda, South Africa, Sudan, Swaziland, Tanzania, Uganda, Zambia, and Zimbabwe. The study includes the methodology and the key results including renewable energy potential for each region.

  4. Freeway Crash Prediction Based on Generalized Linear Regression Models%基于广义线性模型的高速公路交通事故预测

    Institute of Scientific and Technical Information of China (English)

    王迎; 周燕

    2015-01-01

    In order to analysis the impact of traffic state parameters to the freeway crash,a freeway crash prediction model was proposed based on the generalized linear regression models (GLM).Using the traffic flow data and crash data from I-8E freeway in the United States,Negative binomial (NB)pre-diction model and Poisson prediction model based on the real-time traffic flow condition was developed, and the elasticity coefficient calculation method used to confirm the prominent traffic induction parameter was proposed.The results show that the freeway crash can be fitted by the GLM,and the predication ac-curacy of NB model is higher than that of Poisson prediction model.The parameters of traffic volume, share ratio and speed standard deviation have significant affected freeway crashes,and they are in a posi-tive relationship with freeway crash.Traffic volume is the most induction factor that influences freeway crash and an increase of 1 % in traffic volume leads to an increase of 5.8% in freeway crash.%为分析高速公路交通流状态参数对交通事故的影响,建立了基于广义线性模型的高速公路交通事故预测模型。采用美国8号州际高速公路的实时交通流数据和交通事故数据,建立了实时交通流状态下的高速公路泊松分布预测模型和负二项分布预测模型,并给出了模型变量弹性系数的计算方法,用以确定高速公路交通事故的突出诱导因素。研究结果表明:广义线性模型能够很好的拟合高速公路交通事故,并且负二项分布预测模型的预测精度高于泊松分布预测模型;交通量、占有率、大车比例和速度标准差是高速公路交通事故的显著影响参数,并且与之呈正向关系;交通量是诱导高速公路交通事故发生最突出因素,交通量增长1%,可导致交通事故增长5.8%。

  5. Integrating occupancy modeling and interview data for corridor identification: A case study for jaguars in Nicaragua

    Science.gov (United States)

    Zeller, K.A.; Nijhawan, S.; Salom-Perez, R.; Potosme, S.H.; Hines, J.E.

    2011-01-01

    Corridors are critical elements in the long-term conservation of wide-ranging species like the jaguar (Panthera onca). Jaguar corridors across the range of the species were initially identified using a GIS-based least-cost corridor model. However, due to inherent errors in remotely sensed data and model uncertainties, these corridors warrant field verification before conservation efforts can begin. We developed a novel corridor assessment protocol based on interview data and site occupancy modeling. We divided our pilot study area, in southeastern Nicaragua, into 71, 6. ??. 6 km sampling units and conducted 160 structured interviews with local residents. Interviews were designed to collect data on jaguar and seven prey species so that detection/non-detection matrices could be constructed for each sampling unit. Jaguars were reportedly detected in 57% of the sampling units and had a detection probability of 28%. With the exception of white-lipped peccary, prey species were reportedly detected in 82-100% of the sampling units. Though the use of interview data may violate some assumptions of the occupancy modeling approach for determining 'proportion of area occupied', we countered these shortcomings through study design and interpreting the occupancy parameter, psi, as 'probability of habitat used'. Probability of habitat use was modeled for each target species using single state or multistate models. A combination of the estimated probabilities of habitat use for jaguar and prey was selected to identify the final jaguar corridor. This protocol provides an efficient field methodology for identifying corridors for easily-identifiable species, across large study areas comprised of unprotected, private lands. ?? 2010 Elsevier Ltd.

  6. Carbon dynamics of river corridors and the effects of human alterations

    Science.gov (United States)

    Wohl, Ellen; Hall, Robert O.; Lininger, Katherine B; Sutfin, Nicholas A.; Walters, David

    2017-01-01

    Research in stream metabolism, gas exchange, and sediment dynamics indicates that rivers are an active component of the global carbon cycle and that river form and process can influence partitioning of terrestrially derived carbon among the atmosphere, geosphere, and ocean. Here we develop a conceptual model of carbon dynamics (inputs, outputs, and storage of organic carbon) within a river corridor, which includes the active channel and the riparian zone. The exchange of carbon from the channel to the riparian zone represents potential for storage of transported carbon not included in the “active pipe” model of organic carbon (OC) dynamics in freshwater systems. The active pipe model recognizes that river processes influence carbon dynamics, but focuses on CO2 emissions from the channel and eventual delivery to the ocean. We also review how human activities directly and indirectly alter carbon dynamics within river corridors. We propose that dams create the most significant alteration of carbon dynamics within a channel, but that alteration of riparian zones, including the reduction of lateral connectivity between the channel and riparian zone, constitutes the most substantial change of carbon dynamics in river corridors. We argue that the morphology and processes of a river corridor regulate the ability to store, transform, and transport OC, and that people are pervasive modifiers of river morphology and processes. The net effect of most human activities, with the notable exception of reservoir construction, appears to be that of reducing the ability of river corridors to store OC within biota and sediment, which effectively converts river corridors to OC sources rather than OC sinks. We conclude by summarizing knowledge gaps in OC dynamics and the implications of our findings for managing OC dynamics within river corridors.

  7. Variable speed limits control for freeway based on cell transmission model%基于元胞传输模型的高速公路可变限速控制

    Institute of Scientific and Technical Information of China (English)

    马明辉; 杨庆芳; 梁士栋

    2015-01-01

    In order to solve congestion problem on freeway during peak period ,which leads to increase of vehicle delays ,and drop of service level ,an optimization method was proposed for bottleneck re‐gion on freeway mainline based on cell transmission model .Variable speed limits control factors and cell transmission model were combined to describe real‐time traffic flow on freeway .Further ,the op‐timization variable speed limits control model at bottleneck region of freeway was formulated with the objective of improving traffic efficiency and decreasing vehicle delays .T he test results show that opti‐mization variable speed limits control method proposed could improve traffic operation efficiency and traffic order ,especially during congestion hours .%针对高速公路交通拥挤、整体服务水平降低、车辆延误增加等问题,提出了一种基于元胞传输模型的高速公路瓶颈区域可变限速控制方法。将可变限速控制方法同元胞传输模型进行融合,使其对限速条件下高速公路交通流变化进行描述,并以提高通行效率和缩短车辆平均延误为控制目标,建立了高速公路瓶颈区域可变限速最优控制模型。实验证明:在高流量条件下,基于元胞传输模型的高速公路可变限速控制方法具有良好的控制效果,能够有效地提升高速公路整体服务水平。

  8. Remote sensing methods for power line corridor surveys

    Science.gov (United States)

    Matikainen, Leena; Lehtomäki, Matti; Ahokas, Eero; Hyyppä, Juha; Karjalainen, Mika; Jaakkola, Anttoni; Kukko, Antero; Heinonen, Tero

    2016-09-01

    To secure uninterrupted distribution of electricity, effective monitoring and maintenance of power lines are needed. This literature review article aims to give a wide overview of the possibilities provided by modern remote sensing sensors in power line corridor surveys and to discuss the potential and limitations of different approaches. Monitoring of both power line components and vegetation around them is included. Remotely sensed data sources discussed in the review include synthetic aperture radar (SAR) images, optical satellite and aerial images, thermal images, airborne laser scanner (ALS) data, land-based mobile mapping data, and unmanned aerial vehicle (UAV) data. The review shows that most previous studies have concentrated on the mapping and analysis of network components. In particular, automated extraction of power line conductors has achieved much attention, and promising results have been reported. For example, accuracy levels above 90% have been presented for the extraction of conductors from ALS data or aerial images. However, in many studies datasets have been small and numerical quality analyses have been omitted. Mapping of vegetation near power lines has been a less common research topic than mapping of the components, but several studies have also been carried out in this field, especially using optical aerial and satellite images. Based on the review we conclude that in future research more attention should be given to an integrated use of various data sources to benefit from the various techniques in an optimal way. Knowledge in related fields, such as vegetation monitoring from ALS, SAR and optical image data should be better exploited to develop useful monitoring approaches. Special attention should be given to rapidly developing remote sensing techniques such as UAVs and laser scanning from airborne and land-based platforms. To demonstrate and verify the capabilities of automated monitoring approaches, large tests in various environments

  9. Multiple Attributes Decision Making Model for Reasonable Allocation Schemes of Freeway Maintenance Machinery%高速公路养护机械合理配置方案的多属性决策模型

    Institute of Scientific and Technical Information of China (English)

    吴彪; 戴彤焱; 何挺继

    2011-01-01

    以经济性、技术性、协调性、适应性为主要元素,构成表征养护机械配置方案的属性集合;利用三角模糊数的相似度和可能度理论,构建高速公路养护机械合理配置方案的多属性决策模型,模型中通过单目标优化模型确定属性的最优权重向量.以某高速公路机械化养护中心的养护机械配置为例,证明该方法切实可行.%The attributes' sets characterizing maintenance machinery allocation schemes are first constituted using the economy, technicality, coordination and adaptability as the major elements. Then the multi-attribute decision-making model for freeway maintenance machinery allocation schemes is built based on triangular fuzzy number and combined with the concept of similarity degree and possibility degree. The optimal weights are derived by solving an optimization model of simple object. The application of the maintenance machinery allocation of a certain freeway mechanization conservation center is presented for demonstration. Case study shows that the method of multi-object decision-making is feasible and effective. The model provides a new method for decision-making for reasonable allocation of freeway maintenance machinery.

  10. THE BALANCE BETWEEN SUPPLY AND DEMAND OF WATER RESOURCES AND THE WATER—SAVING POTENTIAL FOR AGRICULTURE IN THE HEXI CORRIDOR

    Institute of Scientific and Technical Information of China (English)

    GAOQian-zhao; DUHu-lin; 等

    2002-01-01

    The Hexi Corridor is an important base of agriculture development in Northwest China.According to recent statistics,there are 65.94×108 m3 of water resource available in the Hexi Corridor.At present,net consumption in development and utilization is 43.33×108m3.Water supply and demand reach a balance on the recent level of production ,but loss of evaporation and evapotranspiration is as much as 25.69×108m3.So net use efficiency of water resources is 59%.Based on analyzing balance between water and land considering ecological environment at present,there exists the serious water shortage in the Shiyang River system where irrigation land considering ecological environment at present,there exists the serious water shortage in the Shiyang River system where irrigation lands have overloaded.These is a comparative balance between supply and demand of water resource in the Heibe River system.and the Sule River system has some surplus water to extend irrigation land.Use of agriculture water accounts for 83.3% and ecological forest and grass for 6.9%.The Hexi Corridor still has a great potential for water saving in agriculture production.Water-saving efficiency of irrigation is about 10% by using such traditiona technologies as furrow and border-dike irrigation and small check irrigation,and water-saving wigh plastic film cover and techniques of advanced sprinkler and drip/micro irrigation ete.can save more than 60% of irrigated water.Incremental irrigation area for water-saving potential in the Hexi Corridor has been estimated as 56%-197% to original irrigation area.So the second water sources can be developed from water saving agriculture in the Hexi Corridor under Development of the Western Part of China in large scale .This potential can be realized step by step through developing the water-saving measures,improving the ecological condition of oasis agriculture,and optimizing allocation of water resources in there river systems.

  11. Corridors restore animal-mediated pollination in fragmented tropical forest landscapes.

    Science.gov (United States)

    Kormann, Urs; Scherber, Christoph; Tscharntke, Teja; Klein, Nadja; Larbig, Manuel; Valente, Jonathon J; Hadley, Adam S; Betts, Matthew G

    2016-01-27

    Tropical biodiversity and associated ecosystem functions have become heavily eroded through habitat loss. Animal-mediated pollination is required in more than 94% of higher tropical plant species and 75% of the world's leading food crops, but it remains unclear if corridors avert deforestation-driven pollination breakdown in fragmented tropical landscapes. Here, we used manipulative resource experiments and field observations to show that corridors functionally connect neotropical forest fragments for forest-associated hummingbirds and increase pollen transfer. Further, corridors boosted forest-associated pollinator availability in fragments by 14.3 times compared with unconnected equivalents, increasing overall pollination success. Plants in patches without corridors showed pollination rates equal to bagged control flowers, indicating pollination failure in isolated fragments. This indicates, for the first time, that corridors benefit tropical forest ecosystems beyond boosting local species richness, by functionally connecting mutualistic network partners. We conclude that small-scale adjustments to landscape configuration safeguard native pollinators and associated pollination services in tropical forest landscapes. © 2016 The Author(s).

  12. Engineering monitoring of rockfall hazards along transportation corridors: using mobile terrestrial LiDAR

    Directory of Open Access Journals (Sweden)

    M. Lato

    2009-06-01

    Full Text Available Geotechnical hazards along linear transportation corridors are challenging to identify and often require constant monitoring. Inspecting corridors using traditional, manual methods requires the engineer to be unnecessarily exposed to the hazard. It also requires closure of the corridor to ensure safety of the worker from passing vehicles. This paper identifies the use of mobile terrestrial LiDAR data as a compliment to traditional field methods. Mobile terrestrial LiDAR is an emerging remote data collection technique capable of generating accurate fully three-dimensional virtual models while driving at speeds up to 100 km/h. Data is collected from a truck that causes no delays to active traffic nor does it impede corridor use. These resultant georeferenced data can be used for geomechanical structural feature identification and kinematic analysis, rockfall path identification and differential monitoring of rock movement or failure over time. Comparisons between mobile terrestrial and static LiDAR data collection and analysis are presented. As well, detailed discussions on workflow procedures for possible implementation are discussed. Future use of mobile terrestrial LiDAR data for corridor analysis will focus on repeated surveys and developing dynamic four-dimensional models, higher resolution data collection. As well, computationally advanced, spatially accurate, geomechanically controlled three-dimensional rockfall simulations should be investigated.

  13. Palaeoenvironments of insular Southeast Asia during the Last Glacial Period: a savanna corridor in Sundaland?

    Science.gov (United States)

    Bird, Michael I.; Taylor, David; Hunt, Chris

    2005-11-01

    Consideration of a range of evidence from geomorphology, palynology, biogeography and vegetation/climate modelling suggests that a north-south 'savanna corridor' did exist through the continent of Sundaland (modern insular Indonesia and Malaysia) through the Last Glacial Period (LGP) at times of lowered sea-level, as originally proposed by Heaney [1991. Climatic Change 19, 53-61]. A minimal interpretation of the size of this corridor requires a narrow but continuous zone of open 'savanna' vegetation 50-150 km wide, running along the sand-covered divide between the modern South China and Java Seas. This area formed a land bridge between the Malaysian Peninsula and the major islands of Sumatra, Java and Borneo. The savanna corridor connected similar open vegetation types north and south of the equator, and served as a barrier to the dispersal of rainforest-dependent species between Sumatra and Borneo. A maximal interpretation of the available evidence is compatible with the existence of a broad savanna corridor, with forest restricted to refugia primarily in Sumatra, Borneo and the continental shelf beneath the modern South China Sea. This savanna corridor may have provided a convenient route for the rapid early dispersal of modern humans through the region and on into Australasia.

  14. Influence of Smile Arc and Buccal Corridors on Facial Attractiveness: A Cross-sectional Study

    Science.gov (United States)

    Gaikwad, Shashank; Vaz, Anna C; Singh, Baldeep; Taneja, Lavina; Vinod, KS; Verma, Prateek

    2016-01-01

    Introduction Two aspects of the smile: the Smile Arc (SA) and Buccal Corridors (BC) have been the interest of the orthodontist in recent years. Aim The present study was undertaken to evaluate the influence of the smile arc and buccal corridors on facial attractiveness as evaluated by orthodontists, general dentists and laymen. Materials and Methods Two subjects (one male & one female) were selected from the regional population fulfilling the criteria of an ideal smile arc and ideal buccal corridors. Frontal smile view photographs of these subjects were taken and modified by using adobe photoshop 7.0 to create combination of three smile arc variance and three buccal corridors variations respectively which were shown to 25 orthodontists, 25 general dentists & 25 laymen, to rate the facial attractiveness of each image on a rating scale. Results All the three groups (laypersons, dentists and orthodontists) showed significant difference in ratings, indicating that they had different perceptions on the facial attractiveness. Conclusion Orthodontists were more precise in discerning the smile arc and buccal corridors compared to dentists and laypersons. PMID:27790573

  15. Collision risk-capacity tradeoff analysis of an en-route corridor model

    Directory of Open Access Journals (Sweden)

    Ye Bojia

    2014-02-01

    Full Text Available Flow corridors are a new class of trajectory-based airspace which derives from the next generation air transportation system concept of operations. Reducing the airspace complexity and increasing the capacity are the main purposes of the en-route corridor. This paper analyzes the collision risk-capacity tradeoff using a combined discrete–continuous simulation method. A basic two-dimensional en-route flow corridor with performance rules is designed as the operational environment. A second-order system is established by combining the point mass model and the proportional derivative controller together to simulate the self-separation operations of the aircrafts in the corridor and the operation performance parameters from the User Manual for the Base of Aircraft Data are used in this research in order to improve the reliability. Simulation results indicate that the aircrafts can self-separate from each other efficiently by adjusting their velocities, and rationally setting the values of some variables can improve the rate and stability of the corridor with low risks of loss of separation.

  16. Atmospheric pollution in the Tula Industrial Corridor studied using a bio monitor and nuclear analytical techniques

    Energy Technology Data Exchange (ETDEWEB)

    Martinez C, M. A.; Solis, C.; Andrade, E. [UNAM, Instituto de Fisica, Apdo. Postal 20-364, 01000 Mexico D. F. (Mexico); Beltran H, R. I. [Universidad Autonoma del Estado de Hidalgo, Centro de Investigaciones Quimicas, Carretera Pachuca-Tulancingo Km. 4.5, 42184 Pachuca, Hidalgo (Mexico); Issac O, K. [Universidad Autonoma del Estado de Mexico, Facultad de Medicina, Paseo Tollocan s/n, esq. Jesus Carranza, 50120 Toluca, Estado de Mexico (Mexico); Lucho C, C. A. [Universidad Politecnica de Pachuca, Carretera Pachuca-Cd. Sahagun Km. 20, Hidalgo (Mexico); Lopez R, M. C.; Longoria, L. C. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2011-02-15

    This study deals with the application of nuclear analytical techniques to analyze trace elements in the biological monitor Tillandsia usneoides. Biological monitors provides an alternative advantageous way of particulate matter sampling in air pollution studies, since there is no need of special sampling devices, accumulation time can be as long as desired. T. usneoides, which occurs naturally throughout Mexico, was used to monitor air quality of Tula-Vito-Apasco (TVA) industrial corridor at central Mexico. This area is considered one of the critical zones of the country because of atmospheric contaminants high concentration. Particulate matter is regulated by Mexican norms, but its chemical composition is not. Plants were transplanted from a clean environment to four sites at the TVA corridor, and exposed for 12 weeks from February to April 2008. Trace element accumulation of plants was determined by particle induced X-ray emission and neutron activation analysis. Results reveal differences in trace elements distribution among sites in the TVA corridor. Furthermore, anthropogenic elements (S, V) and crustal elements (Ca) in T. usneoides exhibit high levels. Highly toxic elements such as Hg, As and Cr although present at trace levels, showed un enrichment relative to the initial values, when transplanted to the TVA corridor. Results show that monitoring with T. usneoides allows a first approximation of air sources to provide insights of the atmospheric pollution in the TVA corridor. (Author)

  17. Climate change and plant dispersal along corridors in fragmented landscapes of Mesoamerica.

    Science.gov (United States)

    Imbach, Pablo A; Locatelli, Bruno; Molina, Luis G; Ciais, Philippe; Leadley, Paul W

    2013-09-01

    Climate change is a threat to biodiversity, and adaptation measures should be considered in biodiversity conservation planning. Protected areas (PA) are expected to be impacted by climate change and improving their connectivity with biological corridors (BC) has been proposed as a potential adaptation measure, although assessing its effectiveness remains a challenge. In Mesoamerica, efforts to preserve the biodiversity have led to the creation of a regional network of PA and, more recently, BC. This study evaluates the role of BC for facilitating plant dispersal between PA under climate change in Mesoamerica. A spatially explicit dynamic model (cellular automaton) was developed to simulate species dispersal under different climate and conservation policy scenarios. Plant functional types (PFT) were defined based on a range of dispersal rates and vegetation types to represent the diversity of species in the region. The impacts of climate change on PA and the role of BC for dispersal were assessed spatially. Results show that most impacted PA are those with low altitudinal range in hot, dry, or high latitude areas. PA with low altitudinal range in high cool areas benefit the most from corridors. The most important corridors cover larger areas and have high altitude gradients. Only the fastest PFT can keep up with the expected change in climate and benefit from corridors for dispersal. We conclude that the spatial assessment of the vulnerability of PA and the role of corridors in facilitating dispersal can help conservation planning under a changing climate.

  18. 14 CFR Appendix B to Part 420 - Method for Defining a Flight Corridor

    Science.gov (United States)

    2010-01-01

    ... using a linear interpolation and summation exercise, as shown below in equation B8. An applicant shall... by the cosine of the eccentric anomaly at impact (εc k). ER19OC00.080 (J) An applicant shall compute the eccentricity of the trajectory ellipse multiplied by the sine of the eccentric anomaly at...

  19. Operational Capacity on Freeway Bottleneck Segment%高速公路瓶颈路段运营通行能力研究

    Institute of Scientific and Technical Information of China (English)

    吴德华; 邱志军

    2015-01-01

    高速公路瓶颈路段在发生交通拥堵后会引起运营通行能力突变现象,为了更加准确揭示瓶颈路段运营通行能力变化规律,引入非对称驾驶行为理论,改进Newell跟车模型,并对模型进行参数估计和应用分析.通过12个仿真场景及试验数据对比分析了改进模型和美国道路通行能力手册(2010)推荐模型的精确度,发现改进模型可以提高精度;分析了因车道减少导致的交通拥堵,发现关闭不同车道和车道数对运营通行能力影响结果不同,得出了相应的影响值;在一定交通量范围内,入口匝道和出口匝道交通量的增加都会导致主线拥堵路段运营通行能力的降低,并给出了最大降低幅度.研究结果可为缓解高速公路瓶颈路段交通拥堵提供借鉴.%The traffic congestion can cause operational capacity drop phenomenon on freeway bottleneck segment. To reveal the capacity diversification regular pattern, the asymmetric driver behavior theory is used to improve the Newell car-following model. The improved car-following model is calibrated and implemented in field data simulation. By 12 simulation scenarios and field data analysis, the results show that the improved Newell car-following model can increase accuracy in estimate the bottleneck operational capacity compared to the model that Highway Capacity Manual (HCM2010) provided. The traffic congestion due to the lane drop is analyzed, the operational capacity varied in condition close different lane and number of lanes, then the varied value is figured out. The operational capacity on major lane bottleneck segment decreases by changed the flow on on-ramp and off-ramp in range of certain flow change, and the most decreased value is calculated. In conclusion, the results can provide reference for migrate congestion on freeway bottleneck segment.

  20. An Optimal Deployment of Wireless Charging Lane for Electric Vehicles on Highway Corridors

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yongxi [Clemson University

    2016-01-01

    We propose an integrated modeling framework to optimally locate wireless charging facilities along a highway corridor to provide sufficient in-motion charging. The integrated model consists of a master, Infrastructure Planning Model that determines best locations with integrated two sub-models that explicitly capture energy consumption and charging and the interactions between electric vehicle and wireless charging technologies, geometrics of highway corridors, speed, and auxiliary system. The model is implemented in an illustrative case study of a highway corridor of Interstate 5 in Oregon. We found that the cost of establishing the charging lane is sensitive and increases with the speed to achieve. Through sensitivity analyses, we gain better understanding on the extent of impacts of geometric characteristics of highways and battery capacity on the charging lane design.

  1. Transport corridors as a factor of integration in South-Eastern Europe

    Directory of Open Access Journals (Sweden)

    Grčić Mirko

    2004-01-01

    Full Text Available The benefits of opening the state borders with the stress on its integration function through the constitution of cross-border regions cannot be achieved without a synchronized transport development. For South Eastern European countries, the top priority project would be the formation of pan-European transport corridors defined on Crete in 1994 and amended later on in Helsinki in 1997. Six of ten corridors pass through the territory of South Eastern Europe. Due to their transport and geographical locations, the capitals of the region should represent the key nodes on the main transport directions. Corridor X with its technical, economic and functional characteristics represents the axis of the entire transport network in SE Europe. Formation of this network has as its ultimate goal the functional inter-regional integration with simplified and accelerated transport lines. This also means the open barriers but at the same time, improved and harmonized transport infrastructures and services.

  2. Normative segment-specific axial and coronal angulation corridors of subaxial cervical column in axial rotation.

    Science.gov (United States)

    Yoganandan, Narayan; Stemper, Brian D; Pintar, Frank A; Baisden, Jamie L; Shender, Barry S; Paskoff, Glenn

    2008-03-01

    In contrast to clinical studies wherein loading magnitudes are indeterminate, experiments permit controlled and quantifiable moment applications, record kinematics in multiple planes, and allow derivation of moment-angulation corridors. Axial and coronal moment-angulation corridors were determined at every level of the subaxial cervical spine, expressed as logarithmic functions, and level-specificity of range of motion and neutral zones were evaluated. segmental primary axial and coupled coronal motions do not vary by level. Although it is known that cervical spine responses are coupled, segment-specific corridors of axial and coronal kinematics under axial twisting moments from healthy normal spines are not reported. Ten human cadaver columns (23-44 years, mean: 34 +/- 6.8) were fixed at the ends and targets were inserted to each vertebra to obtain kinematics in axial and coronal planes. The columns were subjected to pure axial twisting moments. Range of motion and neutral zone for primary-axial and coupled-coronal rotation components were determined at each spinal level. Data were analyzed using factorial analysis of variance. Moment-rotation angulations were expressed using logarithmic functions, and mean +/-1 standard deviation corridors were derived at each level for both components. Moment-angulations responses were nonlinear. Each segmental curve for both components was well represented by a logarithmic function (r2 > 0.95). Factorial analysis of variance indicated that the biomechanical metrics are spinal level-specific (P specific responses. The presentation of moment-angulation corridors for both metrics forms a dataset for the normal population. These segment-specific nonlinear corridors may help clinicians assess dysfunction or instability. These data will assist mathematical models of the spine in improved validation and lead to efficacious design of stabilizing systems.

  3. "FluvialCorridor": A new ArcGIS toolbox package for multiscale riverscape exploration

    Science.gov (United States)

    Roux, Clément; Alber, Adrien; Bertrand, Mélanie; Vaudor, Lise; Piégay, Hervé

    2015-08-01

    Both for scientists and river basin managers, development of automated geographic information system (GIS) tools is essential today to characterize riverscapes and explore biogeomorphologic processes over large channel networks. Since the 1990s, GIS toolboxes and add-in programs have been used to characterize catchments. However, there is currently no equivalent to a planimetric and longitudinal characterization of fluvial corridor networks at multiple scales. This paper describes FluvialCorridor, a new GIS toolbox. This package allows the user: (i) to extract a large set of riverscape features such as the main components of fluvial corridors from DEM and vector layers (e.g. stream network or valley bottom), and (ii) to aggregate spatial features into homogeneous segments and metrics characterizing each of them. The methodological frameworks involved have been previously described by Alber and Piégay (2011), Leviandier et al. (2012) and Bertrand et al. (2013) and this contribution focuses on the GIS tools allowing the user to automatically operate them. A case study on the Drôme River (France) is provided to illustrate the potential of the package both for geomorphologic understanding and target management actions. FluvialCorridor has been developed for ArcGIS with the related native Python library named ArcPy and tested on ArcGIS 10.0 and 10.1. Obviously, each component of the package can be used separately; however, it also provides a complete workflow for fluvial corridor characterization, even as the toolbox is continually under development and revision. Case study database, FluvialCorridor package and guidelines are available online at http://umrevs-isig.fr.

  4. The relative influence of catchment, riparian corridor, and reach-scale anthropogenic pressures on fish and macroinvertebrate assemblages in French rivers

    NARCIS (Netherlands)

    Marzin, A.; Verdonschot, P.F.M.; Pont, D.

    2013-01-01

    This study compares the relative influences of physiography and anthropogenic pressures on river biota at catchment, riparian corridor, and reach scales. Environmental data, catchment and riparian corridor land use, anthropogenic modifications and biological data were compiled for 301 French sites

  5. Urban Power Line Corridors as Novel Habitats for Grassland and Alien Plant Species in South-Western Finland.

    Science.gov (United States)

    Lampinen, Jussi; Ruokolainen, Kalle; Huhta, Ari-Pekka

    2015-01-01

    Regularly managed electric power line corridors may provide habitats for both early-successional grassland plant species and disturbance-dependent alien plant species. These habitats are especially important in urban areas, where they can help conserve native grassland species and communities in urban greenspace. However, they can also provide further footholds for potentially invasive alien species that already characterize urban areas. In order to implement power line corridors into urban conservation, it is important to understand which environmental conditions in the corridors favor grassland species and which alien species. Likewise it is important to know whether similar environmental factors in the corridors control the species composition of the two groups. We conducted a vegetation study in a 43 kilometer long urban power line corridor network in south-western Finland, and used generalized linear models and distance-based redundancy analysis to determine which environmental factors best predict the occurrence and composition of grassland and alien plant species in the corridors. The results imply that old corridors on dry soils and steep slopes characterized by a history as open areas and pastures are especially suitable for grassland species. Corridors suitable for alien species, in turn, are characterized by productive soils and abundant light and are surrounded by a dense urban fabric. Factors controlling species composition in the two groups are somewhat correlated, with the most important factors including light abundance, soil moisture, soil calcium concentration and soil productivity. The results have implications for grassland conservation and invasive alien species control in urban areas.

  6. 76 FR 3624 - Milford Wind Corridor Phase II, LLC; Supplemental Notice That Initial Market-Based Rate Filing...

    Science.gov (United States)

    2011-01-20

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Milford Wind Corridor Phase II, LLC; Supplemental Notice That Initial Market... supplemental notice in the above-referenced proceeding Milford Wind Corridor Phase II, LLC's application for...

  7. 76 FR 78641 - Cedar Creek Wind Energy, LLC, Milford Wind Corridor Phase I, LLC; Notice of Filing

    Science.gov (United States)

    2011-12-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Cedar Creek Wind Energy, LLC, Milford Wind Corridor Phase I, LLC; Notice of...'s (Commission) June 16, 2011 Order.\\1\\ \\1\\ Cedar Creek Wind Energy, LLC and Milford Wind Corridor...

  8. Composition and abundance of small mammal communities in forest fragments and vegetation corridors in Southern Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Andréa O. Mesquita

    2012-09-01

    Full Text Available Habitat fragmentation leads to isolation and reduce habitat areas, in addition to a series of negative effects on natural populations, affecting richness, abundance and distribution of animal species. In such a text, habitat corridors serve as an alternative for connectivity in fragmented landscapes, minimizing the effects of structural isolation of different habitat areas. This study evaluated the richness, composition and abundance of small mammal communities in forest fragments and in the relevant vegetation corridors that connect these fragments, located in Southern Minas Gerais, Southeastern Brazil. Ten sites were sampled (five forest fragments and five vegetation corridors using the capture-mark-recapture method, from April 2007-March 2008. A total sampling effort of 6 300 trapnights resulted in 656 captures of 249 individuals. Across the 10 sites sampled, 11 small mammal species were recorded. Multidimensional scaling (MDS ordinations and ANOSIM based on the composition of small mammal communities within the corridor and fragment revealed a qualitative difference between the two environments. Regarding abundance, there was no significant difference between corridors and fragments. In comparing mean values of abundance per species in each environment, only Cerradomys subflavus showed a significant difference, being more abundant in the corridor environment. Results suggest that the presence of several small mammal species in the corridor environment, in relatively high abundances, could indicate corridors use as habitat, though they might also facilitate and/or allow the movement of individuals using different habitat patches (fragments.

  9. Green corridors and their possible impact on the European supply chain

    DEFF Research Database (Denmark)

    Panagakos, George; Psaraftis, Harilaos N.; Holte, Even Ambros

    2015-01-01

    The purpose of this chapter is to present the concept of green corridors and analyse their possible impact on the supply chain. The basis of this material is work conducted in the context of the EU SuperGreen project and therefore the geographical setting of the chapter is Europe. The general...... however that the quality of transport and logistics services is also affected by passenger transport competing for route capacity. Aviation is outside the scope of our analysis, as is the use of pipelines for liquid cargoes. In addition, the chapter provides examples of the corridor development approaches...

  10. On sustainable development of agriculture in oasis: a case study of Hexi Corridor, Gansu, China

    Institute of Scientific and Technical Information of China (English)

    Wang Limin

    2007-01-01

    Hexi Corridor is one of the most potential areas in the China's Western Development in 21s' century.However,the problems - the sustainable development of oasis agriculture,the ecosystem of the oasis edge,the landscape structure,the population density in oasis,water resources and land resources in oasis are deteriorating and have restricted the sustainable development of society and economy in this area.This paper summarizes the problems at present,and puts forward the concept of protecting and constructing the oasis environment and sustainable development for the sustainable development of the oasis agriculture in the Hexi Corridor.

  11. Territoriality by conservation in the Selous-Niassa corridor in Tanzania

    DEFF Research Database (Denmark)

    Bluwstein, Jevgeniy; Lund, Jens Friis

    2017-01-01

    In this paper we argue that historically emerging frontiers of conservation pave the way for continuous territorialization. Drawing on a concrete case in the Selous-Niassa Corridor in Southern Tanzania, we show how a frontier emerged in form of community-based conservation and decades of consecut......In this paper we argue that historically emerging frontiers of conservation pave the way for continuous territorialization. Drawing on a concrete case in the Selous-Niassa Corridor in Southern Tanzania, we show how a frontier emerged in form of community-based conservation and decades...

  12. Perspective on traffic control: Aspects of freeway control, intersection control and the control of transit flow in the Netherlands

    NARCIS (Netherlands)

    Hakkesteegt, P.

    1988-01-01

    Paper presented at the 1988 TRB Annual Meeting, Washington D.C., USA. The first part of this paper deals with the control and signalling system for motorways, directed to a more efficient use of available road capacity and to the improvement of road safety. The second part gives some insight into th

  13. Probability Forecast Method for Freeway Traffic Accidents%高速公路交通事故概率预测方法研究

    Institute of Scientific and Technical Information of China (English)

    王少群; 张晓明

    2014-01-01

    准确的高速公路交通事故概率预测可提高高速公路行车安全。通过分析高速公路交通事故的影响因素,建立高速公路交通事故影响因素体系,构造贝叶斯网络,提出基于贝叶斯网络的高速公路交通事故概率预测方法。此方法利用数据库先验概率信息及贝叶斯预测模型,得出高速公路交通事故概率值,以此判断事故危险等级。%Precise probability forecast for freeway traffic accidents is an important means to improve traffic safety. By analyzing the influence factors of highway traffic accidents, this paper establishes a Bayesian network, and develops the probability forecast method based on Bayesian network. This method determines the level of risk by analyzing the distribution of the accident probability values, after deriving them by using database prior probability information and Bayesian model.

  14. Health Risk Assessment for Transport Corridors in Delhi through Vehicular Air Polluting Mapping

    Directory of Open Access Journals (Sweden)

    Nitin Kumar

    2016-09-01

    Full Text Available Vehicles are recognized as one of the major sources of air pollution. Delhi having  a very large number of vehicles produces a lot of air pollution. There is an utter need to ascertain the concentration of the pollutants and their impact on the health of the people of the concerned region. This paper makes an attempt towards such an examination. The method employed here is based on Epidemiology. The assessment of health risks due to increased levels of various pollutants on people represented in this paper is based on the spreadsheet model, Risk of Mortality/Morbidity due to Air Pollution (Ri–MAP. This paper presents the findings of the study that evaluates the Impact of increasing air pollution on human health, especially vehicular pollution, in the monitored region, i.e., National Capital Territory of Delhi (NCT Delhi during the year 2015 by choosing fifteen study sites from different parts of the capital city. The findings are in terms of  excess number of cases of cardiovascular and respiratory mortality, and cardiovascular and respiratory morbidity for all fifteen transport corridors. Among others, Noida link road recorded highest excess number of cases of cardiovascular mortality and morbidity and respiratory Morbidity. In case of respiratory mortality, Wazirabad road recorded maximum excess number of cases. With respect to least excess number of cases, it was Connaught Place (Outer circle. The excess number of cases are directly proportional to the population density of the respective region. Also, the regions showing smaller excess number of cases are the planned, less crowded and posh regions of the national capital territory of Delhi.

  15. Albania – as the Bridge of Routes and Transport Corridors between the Adriatic Sea and Black Sea

    Directory of Open Access Journals (Sweden)

    Ramadan Mazrekaj

    2015-07-01

    Full Text Available Republic of Albania is located in the Western Balkans. Its location in the midst of crossroads for major transit corridors in Europe places Albania in a strategic geographic position. Albania links the western Mediterranean countries with the Balkans and Asia. Its biggest valleys situated in Drin, Shkumbin and Vjose rivers, facilitate the connection of the Balkans with the Adriatic Sea. In the Balkan territory are situated some of the most important Pan - European transport corridors, consisting of: Pan - European Corridor IV, V, VII, VIII, IX and X. Main objective of this paper is the analysis of the development of transport routes and corridors in the Balkans in the context of Pan-European corridors; evaluation of national policy, priorities of Transport, directions of Albania’s main road and their compatibility with the needs of Pan - European connectivity.

  16. 33 CFR 334.770 - Gulf of Mexico and St. Andrew Sound, south of East Bay, Fla., Tyndall Drone Launch Corridor...

    Science.gov (United States)

    2010-07-01

    ... Sound, south of East Bay, Fla., Tyndall Drone Launch Corridor, Tyndall Air Force Base, Fla.; restricted.... Andrew Sound, south of East Bay, Fla., Tyndall Drone Launch Corridor, Tyndall Air Force Base, Fla... referred to as the “Tyndall Drone Launch Corridor.” (b) The regulations. (1) Military usage of areas...

  17. First steps toward automatic patterns recognition from sequences of a restored river corridor photographs

    Science.gov (United States)

    Nouta, S.; Perona, P.; Schneider, P.; Wombacher, A.; Burlando, P.

    2009-04-01

    Obtaining information about river morphology and riparian vegetation patterns by means of photographic techniques is a challenging task with promising applications in the field of river hydraulic engineering and restoration. For instance, such a tool would speed up the post- processing phase of aerial images that is needed to calibrate both hydraulics and ecosystem models. Recognizing patterns automatically is relatively easy in the presence of well-defined objects and contrasting background colors, but this operation becomes rather difficult for open air or environmental photographs (e.g. of river corridors) where a multitude of colors, shadows, reflections and changing light conditions typically characterize the images. In this work an attempt is made in this direction and we begin with the already challenging task of recognizing water and non-water classes from digital photographs under changing light and surface albedo. Such conditions are typically due to either diurnal variability or bad weather conditions (e.g., like fog or snow). We use aerial photographs of the restored corridor of River Thur at Niederneunforn (Switzerland), which is currently monitored with high-resolution digital cameras as a task of the research project RECORD. Images of the river reach are taken from the top of two observation towers installed on the river levee and shots are frequency-dependent on current flow conditions. The approach we present here consists of masking the images by ignoring the irrelevant parts like mountains and sky, for instance. Next, features are defined which describe properties of the image or the image content, like e.g. color values, gradients of neighboring pixels, or application specific information like a probability distribution of a pixel being water derived from the digital elevation model. The investigated features can be classified according to two orthogonal dimensions: i) Pixel based features and features derived from a group of pixels and ii) Time

  18. Sailing From the Seas of Chaos Into the Corridor of Stability: Practical Recommendations to Increase the Informational Value of Studies.

    Science.gov (United States)

    Lakens, Daniël; Evers, Ellen R K

    2014-05-01

    Recent events have led psychologists to acknowledge that the inherent uncertainty encapsulated in an inductive science is amplified by problematic research practices. In this article, we provide a practical introduction to recently developed statistical tools that can be used to deal with these uncertainties when performing and evaluating research. In Part 1, we discuss the importance of accurate and stable effect size estimates as well as how to design studies to reach a corridor of stability around effect size estimates. In Part 2, we explain how, given uncertain effect size estimates, well-powered studies can be designed with sequential analyses. In Part 3, we (a) explain what p values convey about the likelihood that an effect is true, (b) illustrate how the v statistic can be used to evaluate the accuracy of individual studies, and (c) show how the evidential value of multiple studies can be examined with a p-curve analysis. We end by discussing the consequences of incorporating our recommendations in terms of a reduced quantity, but increased quality, of the research output. We hope that the practical recommendations discussed in this article will provide researchers with the tools to make important steps toward a psychological science that allows researchers to differentiate among all possible truths on the basis of their likelihood.

  19. War and wildlife: a post-conflict assessment of Afghanistan's Wakhan Corridor

    NARCIS (Netherlands)

    Mishra, C.; Fitzherbert, A.

    2004-01-01

    Prior to the last two decades of conflict, Afghanistan¿s Wakhan Corridor was considered an important area for conservation of the wildlife of high altitudes. We conducted an assessment of the status of large mammals in Wakhan after 22 years of conflict, and also made a preliminary assessment of wild

  20. Lessons Learned during Creation of the I-65 Biofuels Corridor (White Paper)

    Energy Technology Data Exchange (ETDEWEB)

    2009-06-01

    A team of Clean Cities coalitions and state agencies worked together to create a biofuels corridor along I-65 between Indiana and Alabama. The team built relationships with stakeholders and learned the value of strong partnerships, good communication, marketing, and preparation.

  1. Weakest link or strongest node? Prospects for inland port development in transnational European corridors

    NARCIS (Netherlands)

    Witte, P.A.; Wiegmans, Bart

    2015-01-01

    In a context of increasing global freight transportation and transnational corridor development, inland ports are becoming more important in enhancing hinterland accessibility of deep-sea ports. At the same time, however, when considering the ‘weakest link’ principle, the increasing reliance on inla

  2. POTENTIAL AREAS FOR THE FORMATION OF ECOLOGICAL CORRIDORS BETWEEN REMNANTS OF ATLANTIC FOREST

    Directory of Open Access Journals (Sweden)

    João Flávio Costa dos Santos

    Full Text Available ABSTRACT In Brazil, the remaining areas of Atlantic Forest are intensely fragmented. The connection of forest fragments through ecological corridors is an important step in biodiversity conservation. Certain areas are more resilient, and in those areas, natural forest regeneration, for example, can be encouraged. The aim of this study was to identify areas of greater resilience in order to support the connection of Atlantic Forest fragments with ecological corridors. Forest fragments in the municipality of Paraíba do Sul, in the state of Rio de Janeiro, were mapped using the supervised maximum likelihood classification of an Operational Land Imager (OLI/Landsat-8 sensor image. Next, we analyzed the influence of terrain attributes (aspect, incident solar radiation, slope, and curvature profile on natural regeneration. The areas with the greatest potential to achieve natural regeneration and to form ecological corridors were indicated through fuzzy membership functions. Within Paraíba do Sul, 31% of the territory is covered by vegetation in different stages of regeneration. Recordings were made of 1,251 forest fragments in a middle or advanced stage of regeneration. These fragments are usually situated in the southeast, south, and southwest aspects, in areas that receive the least amount of global solar radiation (Wh·m-2 per year, and on slopes with an angle of inclination greater than 20%. The adjustment of fuzzy functions identified 17,327.5 ha with a tendency to recover, and which are therefore strategic areas in the development of ecological corridors.

  3. War and wildlife: a post-conflict assessment of Afghanistan's Wakhan Corridor

    NARCIS (Netherlands)

    Mishra, C.; Fitzherbert, A.

    2004-01-01

    Prior to the last two decades of conflict, Afghanistan¿s Wakhan Corridor was considered an important area for conservation of the wildlife of high altitudes. We conducted an assessment of the status of large mammals in Wakhan after 22 years of conflict, and also made a preliminary assessment of wild

  4. Strategic Mobility 21: Smart and Secure E Corridor Stakeholder Evaluation - Savannah

    Science.gov (United States)

    2009-12-07

    Global Business Center Mr. Bill Dobbs, GA Dept. of Economic Development Executable Smart Corridor ‘Use Cases’ Information Domain Physical Domain...Investment: Recent Research Trends and Emerging Issues Kent Hindes, Cushman Wakefield Presentation Georgia: A Global Business Center Mr. Bill

  5. 75 FR 10332 - In the Matter of: Corridor Communications Corp., International Cosmetics Marketing Co., PNV, Inc...

    Science.gov (United States)

    2010-03-05

    ... Communications Corp., International Cosmetics Marketing Co., PNV, Inc., Questron Technology, Inc. (n/k/a Quti... securities of Corridor Communications Corp. because it has not filed any periodic reports since the period... current and accurate information concerning the securities of International Cosmetics Marketing...

  6. Customer Satisfaction Perceptions of Dislocated Workers Served by WIN Job Centers in the Mississippi Corridor Consortium

    Science.gov (United States)

    Washburn, Dava Michelle

    2009-01-01

    The purpose of this study was to determine the perceptions of satisfaction of dislocated workers served by WIN Job Centers in the Mississippi Corridor Consortium. Four WIN Job Centers participated in this study: Northeast Mississippi Community College WIN Job Center in Corinth, Northwest Mississippi Community College WIN Job Center in Oxford,…

  7. Evidence of a southward eddy corridor in the South-West Indian ocean

    CSIR Research Space (South Africa)

    Ansorge, IJ

    2015-09-01

    Full Text Available of this eddy corridor appears to be restricted to the deep channel separating the Conrad Rise from the Del Cano and Crozet Plateau. However, while the fate of eddies formed at the SWIR has been widely investigated and the frontal character of this eastward...

  8. Thermal Comfort At The Street Corridor Around Public Places, Case Study Alun-Alun Malang City

    Directory of Open Access Journals (Sweden)

    Erna Winansih

    2016-01-01

    Full Text Available Malang as the second largest city in East Java province become crowded recently. The congestion almost happens everyday. The scenery of the street corridor is full of iron stacks. It is said that Malang city is less comfortable and less walkable. The decrease of this environment encourages to conduct the study (Q.S. 16:90, Q.S. 96:1-5, Q.S. 30:41. The study aimed to analyze the thermal comfort at pedestrian ways around Malang city squares, the street corridor of Merdeka Alun-Alun (MAA and the Tugu Alun-Alun (TAA. The temperature and relative humidity were measured by multinorm instrument. The THI (Temperature Humidity Index method was used to analyze the thermal comfort. The results showed that the THI average at TAA (27 were more comfortable than at MAA (27,5. The south side of the MAA corridor became the most comfortable with the THI value of 26,4, which the side covered by trees canopy (Q.S. 7:58. It needs to conduct next research (Q.S. 13:11, because of the change of the activities at these street corridors.

  9. Model-based corridor performance analysis – An application to a European case

    DEFF Research Database (Denmark)

    Panagakos, George; Psaraftis, Harilaos N.

    2017-01-01

    , to the extent covered by the GreCOR application, the proposed methodology can effectively assess the performance of a freight transport corridor. Combining the model-based approach for the sample construction with the study-based approach for the estimation of chain-level indicators exploits the strengths...

  10. Model-based corridor performance analysis – An application to a European case

    DEFF Research Database (Denmark)

    Panagakos, George; Psaraftis, Harilaos N.

    2017-01-01

    , to the extent covered by the GreCOR application, the proposed methodology can effectively assess the performance of a freight transport corridor. Combining the model-based approach for the sample construction and the study-based approach for the estimation of chain-level indicators exploits the strengths...

  11. The Corridor Principle and the Near Failure Syndrome: Two Generic Concepts with Practical Value for Entrepreneurs

    Science.gov (United States)

    Ronstadt, Robert

    2007-01-01

    In this article, the author defines the Corridor Principle, which explains how entrepreneurs are able to use knowledge and insight from earlier ventures to see new venture opportunities that they could not have seen and/or pursued had they not started an earlier venture. He discusses its importance to practitioners in allowing them to anticipate…

  12. Working on rail freigt corridors : a trade union manual anticipate - take action - work together

    NARCIS (Netherlands)

    Goudswaard, A.; Torre, W. van der; Verbiest, S.

    2013-01-01

    The European Transport Workers Federation (ETF) put in place in 2013 the project “WOC – Working On Rail Freight Corridors” with the objective to on the one hand raise awareness among ETF affiliates about the developments of the European freight corridors and on the other hand to give the tools to an

  13. [Ecological and economic harmony evaluation and spatial evolution of the Hexi corridor, northwest China].

    Science.gov (United States)

    Liu, Hai-long; Shi, Pei-ji; Li, Sheng-mei; Tong, Hua-li; Nie, Xiao-ying; Wei, Wei

    2014-12-01

    The relationship between economic development and environment and the evolution characteristics of spatial pattern in Hexi Corridor of Northwest China were analyzed based on Landsat images in 1985, 1995, 2000 and 2011 with twenty counties in Hexi Corridor chosen as the basic research units. The ecological economic harmony during 1985-2011 was estimated according to ESV (ecosystem services value) and EEH (ecological and economic harmony) index with the ecosystem services value estimation methods. The results showed that the land type of the study area dramatically changed during the study period, the grassland decreased badly, and the construction land and cultivated land increased quickly. The ESV showed an overall downward trend, especially in the Shiyang River basin and the middle of Heihe River. The ESV in the Shule River basin in this period. After 2000, the economic growth speeded up visibly in the study area. The economic development concentrated in the resource-based cities and regional central cities, and declined from the center of corridor to the both sides. The ecological-economic relation in Hexi Corridor experienced a transformation of "preliminary deterioration--further deterioration--low grade coordination". The EEH had large changes in the Shiyang River basin and the middle of Heihe River, which experienced a transformation of "conflict--more conflicts--less conflicts", however, there was little change in Shule River basin. The development mode and the comprehensive reclamation of Shiyang River basin and Heihe River basin had a significant influence on the regional ecological and economic harmony.

  14. Customer Satisfaction Perceptions of Dislocated Workers Served by WIN Job Centers in the Mississippi Corridor Consortium

    Science.gov (United States)

    Washburn, Dava Michelle

    2009-01-01

    The purpose of this study was to determine the perceptions of satisfaction of dislocated workers served by WIN Job Centers in the Mississippi Corridor Consortium. Four WIN Job Centers participated in this study: Northeast Mississippi Community College WIN Job Center in Corinth, Northwest Mississippi Community College WIN Job Center in Oxford,…

  15. Small mammal distributions relative to corridor edges within intensively managed southern pine plantations.

    Science.gov (United States)

    Nicole L. Constantine; Tyler A. Campbell; William M. Baughman; Timothy B. Harrington; Brian R. Chapman; Karl V. Miller

    2005-01-01

    We characterized small mammal communities in three loblolly pine (Pinus taeda) stands in the Lower Coastal Plain of South Carolina during June 1998-Aug. 2000 to investigate influence of corridor edges on small mammal distribution. We live-trapped small mammals in three regenerating stands following clearcutting. Harvested stands were bisected by...

  16. Environmental Assessment for Proposed Utility Corridors at Edwards Air Force Base, California

    Science.gov (United States)

    2016-07-01

    Edwards Air Force Base, California CNPS California Native Plant Society CO Carbon monoxide CO2 Carbon dioxide CO2e Carbon dioxide equivalent mass ...corridors include existing easements, north-south and east-west traversing the Base and take into consideration current easements, communication ...73 3.7.3 Wildlife Communities

  17. Restoring habitat corridors in fragmented landscapes using optimization and percolation models

    Science.gov (United States)

    Justin C. Williams; Stephanie A. Snyder

    2005-01-01

    Landscape fragmentation and habitat loss are significant threats to the conservation of biological diversity. Creating and restoring corridors between isolated habitat patches can help mitigate or reverse the impacts of fragmentation. It is important that restoration and protection efforts be undertaken in the most efficient and effective way possible because...

  18. Fragmentation of Araucaria Forests in the Chapecó Ecological Corridor, Santa Catarina

    Directory of Open Access Journals (Sweden)

    Gisele Garcia Alarcon

    2011-09-01

    Full Text Available In Brazil, only 2% of the Araucaria forest remains, and less than 1% of this forest is protected (as conservation units. In Santa Catarina, the Chapecó River sub-basin was evaluated for the creation of a state ecological corridor. Studies were developed within the Microbacias 2 Project between 2007 and 2009. Landscape metrics provided important data for evaluating the conservation status of the forest remnants for the zoning of the corridor. The Chapecó Ecological Corridor encompasses around 5,000km²; 50.5% of this area comprises remnants of natural ecosystems and 42.7% is used by agricultural activities. Fifteen fragments, which are each larger than 500ha, are Araucaria forests that contain elements of Floresta Estacional Decidual. Of the 83 watersheds studied in permanent preservation areas, 20.5% has more than 60% vegetation cover and 57.5% has between 10% and 30% vegetation cover. It is estimated that the sub-basin has 111,000km2 of forest on private properties, along with remnants in three conservation units and three indigenous areas. The forests of the Chapecó Ecological Corridor represent the last fragments of continuous Araucaria forest in western Santa Catarina.

  19. Tracing overhead transmission line corridors with regard to environmental and spatial qualities

    Directory of Open Access Journals (Sweden)

    Alenka Cof

    2005-01-01

    Full Text Available The article deals with possibilities for running the proposed overhead transmission line Okroglo-Italian border. The Slovene and Italian methods are shown as methods enabling consideration of environmental and spatial impact within the process of planning overhead transmission line corridors. The Slovene method consists of analyses of attractiveness and vulnerability, whereby the first considers those functional and economic factors that affect spatial attractiveness for overhead transmission lines. Thus we can assess the level of economic and functional suitability of alternative routes of the proposed 400 kilovolt overhead transmission line from transformation station Okroglo (Slovenia to Srednje, Golo Brdo and Vrtojba, three potential contact points on the Slovene–Italian border. In accordance with stipulations of the Law on spatial management vulnerability models were prepared, which were used to simulate the development’s potential negative environmental effects and to analyse suitability, which implies harmonisation of development and protection demands. Their result is a possible corridor that can be developed without significant conflicts. The Italian procedure was developed to trace the transmission line corridor from the Slovenian border to the transformation station in Udine. It was also applied on the Slovenian side. Three groups of factors were considered in the procedure: exclusion, repulsion, and attraction. The much simpler procedure enables comparisons, since it uses the same or at least similar spatial data. In conclusion a short commentary is added about the corridor concept as a planning tool.

  20. Identification of priority conservation areas and potential corridors for jaguars in the Caatinga biome, Brazil.

    Directory of Open Access Journals (Sweden)

    Ronaldo Gonçalves Morato

    Full Text Available The jaguar, Panthera onca, is a top predator with the extant population found within the Brazilian Caatinga biome now known to be on the brink of extinction. Designing new conservation units and potential corridors are therefore crucial for the long-term survival of the species within the Caatinga biome. Thus, our aims were: 1 to recognize suitable areas for jaguar occurrence, 2 to delineate areas for jaguar conservation (PJCUs, 3 to design corridors among priority areas, and 4 to prioritize PJCUs. A total of 62 points records of jaguar occurrence and 10 potential predictors were analyzed in a GIS environment. A predictive distributional map was obtained using Species Distribution Modeling (SDM as performed by the Maximum Entropy (Maxent algorithm. Areas equal to or higher than the median suitability value of 0.595 were selected as of high suitability for jaguar occurrence and named as Priority Jaguar Conservation Units (PJCU. Ten PJCUs with sizes varying from 23.6 km2 to 4,311.0 km2 were identified. Afterwards, we combined the response curve, as generated by SDM, and expert opinions to create a permeability matrix and to identify least cost corridors and buffer zones between each PJCU pair. Connectivity corridors and buffer zone for jaguar movement included an area of 8.884,26 km2 and the total corridor length is about 160.94 km. Prioritizing criteria indicated the PJCU representing c.a. 68.61% of the total PJCU area (PJCU # 1 as of high priority for conservation and connectivity with others PJCUs (PJCUs # 4, 5 and 7 desirable for the long term survival of the species. In conclusion, by using the jaguar as a focal species and combining SDM and expert opinion we were able to create a valid framework for practical conservation actions at the Caatinga biome. The same approach could be used for the conservation of other carnivores.

  1. Buccal Corridors: A Fact or a Myth in the Eyes of Laymen?

    Science.gov (United States)

    Elhiny, Omnia A.; Harhash, Asmaa Y.

    2016-01-01

    AIM: This study aimed to investigate laymen knowledge of the existence of the buccal corridor and whether it was an important factor for them in judging smile attractiveness and the effect of introducing the knowledge to them on their further judgment. MATERIALS AND METHODS: Nine subjects were randomly selected with variable buccal corridor percentages. They were coached to smile in a posed fashion and full face smile photographs were taken from a standardised distance. The photographs were randomly arranged in a power point presentation and displayed to a panel of thirty-nine randomly selected laymen judges. The judges made their beauty judgment on a visual analogue scale (VAS) and filled a questionnaire. After their education about the buccal corridor, they were asked to make a second judgment on a second sheet with VAS and with a different random sequence of the photographs. RESULTS: Intra-class correlation agreement for all the judges between the first and second scores was 0.713. The Spearman’s rho Correlation coefficient indicated a positive correlation for all the photos. For the male judges, the agreement between the ratings was 0.839, and the correlation was positive for all the photos. For the female judges, the agreement between the ratings was 0.510, and the correlation was positive for all the photographs. Hundred percent of the judges were not familiar with the buccal corridor. Eighty percent of the female judges and 44.4% of the male judges mentioned that it would affect their further judgment. CONCLUSION: Laymen build their esthetic judgments on what we teach them, and modifying treatment plans to include corrections of buccal corridors for esthetic reasons only is a myth. PMID:28028418

  2. Identification of priority conservation areas and potential corridors for jaguars in the Caatinga biome, Brazil.

    Science.gov (United States)

    Morato, Ronaldo Gonçalves; Ferraz, Katia Maria Paschoaletto Micchi de Barros; de Paula, Rogério Cunha; de Campos, Cláudia Bueno

    2014-01-01

    The jaguar, Panthera onca, is a top predator with the extant population found within the Brazilian Caatinga biome now known to be on the brink of extinction. Designing new conservation units and potential corridors are therefore crucial for the long-term survival of the species within the Caatinga biome. Thus, our aims were: 1) to recognize suitable areas for jaguar occurrence, 2) to delineate areas for jaguar conservation (PJCUs), 3) to design corridors among priority areas, and 4) to prioritize PJCUs. A total of 62 points records of jaguar occurrence and 10 potential predictors were analyzed in a GIS environment. A predictive distributional map was obtained using Species Distribution Modeling (SDM) as performed by the Maximum Entropy (Maxent) algorithm. Areas equal to or higher than the median suitability value of 0.595 were selected as of high suitability for jaguar occurrence and named as Priority Jaguar Conservation Units (PJCU). Ten PJCUs with sizes varying from 23.6 km2 to 4,311.0 km2 were identified. Afterwards, we combined the response curve, as generated by SDM, and expert opinions to create a permeability matrix and to identify least cost corridors and buffer zones between each PJCU pair. Connectivity corridors and buffer zone for jaguar movement included an area of 8.884,26 km2 and the total corridor length is about 160.94 km. Prioritizing criteria indicated the PJCU representing c.a. 68.61% of the total PJCU area (PJCU # 1) as of high priority for conservation and connectivity with others PJCUs (PJCUs # 4, 5 and 7) desirable for the long term survival of the species. In conclusion, by using the jaguar as a focal species and combining SDM and expert opinion we were able to create a valid framework for practical conservation actions at the Caatinga biome. The same approach could be used for the conservation of other carnivores.

  3. Comparative landscape genetics of two frugivorous bats in a biological corridor undergoing agricultural intensification.

    Science.gov (United States)

    Cleary, Katherine A; Waits, Lisette P; Finegan, Bryan

    2017-07-03

    Agricultural intensification in tropical landscapes poses a new threat to the ability of biological corridors to maintain functional connectivity for native species. We use a landscape genetics approach to evaluate impacts of expanding pineapple plantations on two widespread and abundant frugivorous bats in a biological corridor in Costa Rica. We hypothesize that the larger, more mobile Artibeus jamaicensis will be less impacted by pineapple than the smaller Carollia castanea. In 2012 and 2013, we sampled 735 bats in 26 remnant forest patches surrounded by different proportions of forest, pasture, crops and pineapple. We used 10 microsatellite loci for A. jamaicensis and 16 microsatellite loci for C. castanea to estimate genetic diversity and gene flow. Canonical correspondence analyses indicate that land cover type surrounding patches has no impact on genetic diversity of A. jamaicensis. However, for C. castanea, both percentage forest and pineapple surrounding patches explained a significant proportion of the variation in genetic diversity. Least-cost transect analyses (LCTA) and pairwise G″st suggest that for A. jamaicensis, pineapple is more permeable to gene flow than expected, while as expected, forest is the most permeable land cover for gene flow of C. castanea. For both species, LCTA indicate that development may play a role in inhibiting gene flow. The current study answers the call for landscape genetic research focused on tropical and agricultural landscapes, highlights the value of comparative landscape genetics in biological corridor design and management and is one of the few studies of biological corridors in any ecosystem to implement a genetic approach to test corridor efficacy. © 2017 John Wiley & Sons Ltd.

  4. Perceptions of brachyfacial, mesofacial and dolichofacial individuals with regard to the buccal corridor in different facial types

    Directory of Open Access Journals (Sweden)

    Matheus Melo PITHON

    2014-10-01

    Full Text Available Objective: Evaluate the esthetic perception and attractiveness of the smile with regard to the buccal corridor in different facial types by brachyfacial, mesofacial and dolichofacial individuals. Material and Methods: The image of a smiling individual with a mesofacial type of face was changed to create three different facial types with five different buccal corridors (2%, 10%, 15%, 22% and 28%. To achieve this effect, a photo editing software was used (Adobe Photoshop, Adobe Systems Inc, San Francisco, CA, EUA. The images were submitted to evaluators with brachyfacial, mesofacial and dolichofacial types of faces, who evaluated the degree of esthetic perception and attractiveness by means of a visual analog scale measuring 70 mm. The differences between evaluators were verified by the Mann-Whitney test. All statistics were performed with a confidence level of 95%. Results: Brachyfacial individuals perceived mesofacial and dolichofacial types of faces with buccal corridor of 2% as more attractive. Mesofacial individuals perceived mesofacial and dolichofacial types of faces with buccal corridor of 2%, 10% and 15% as more attractive. Dolichofacial individuals perceived the mesofacial type of face with buccal corridor of 2% as more attractive. Evaluators of the female sex generally attributed higher scores than the male evaluators. Conclusion: To achieve an enhanced esthetic smile it is necessary to observe the patient’s facial type. The preference for narrow buccal corridors is an esthetic characteristic preferred by men and women, and wide buccal corridors are less attractive.

  5. Monitoring of fogwater chemistry in the gulf coast urban industrial corridor: Baton Rouge (louisiana).

    Science.gov (United States)

    Raja, S; Ravikrishna, R; Kommalapati, R R; Valsaraj, K T

    2005-11-01

    Seventeen fog events were sampled in Baton Rouge, Louisiana during 2002-2004 as part of characterizing wet deposition by fogwater in the heavily industrialized corridor along the Louisiana Gulf Coast in the United States. These samples were analyzed for chemical characteristics such as pH, conductivity, total organic and inorganic carbon, total metals and the principal ion concentrations. The dominant ionic species in all samples were NH4+, NO3-, Cl- and SO4(2-). The pH of the fogwater sampled had a mean value of 6.7 with two cases of acidic pH of 4.7. Rainwater and fogwater pH were similar in this region. The acidity of fogwater was a result of NO3- but partly offset by high NH4+. The measured gaseous SO2 accounted for a small percentage of the observed sulfate concentration, indicating additional gas-to-particle conversion of SO2 to sulfate in fogwater. The gaseous NOx accounted for most of the dissolved nitrate and nitrite concentration in fogwater. The high chloride concentration was attributable to the degradation of chlorinated organics in the atmosphere. The metal composition was traced directly to soil-derived aerosol precursors in the air. The major metals observed in fogwater were Na, K, Ca, Fe, Al, Mg and Zn. Of these Na, K, Ca and Mg were predominant with mean concentrations > 100 microM. Al, Fe and Zn were present in the samples, at mean concentrations < 100 microM. Small concentrations of Mn (7.8 microM), Cu (2 microM), Pb (0.07 microM) and As (0.32 microM) were also observed in the fogwaters, and these were shown to result from particulates (PM2.5) in the atmosphere. The contribution to both ions and metals from the marine sources in the Louisiana Gulf Coast was minimal. The concentrations of all principal ionic species and metals in fogwater were 1-2 orders of magnitude larger than in rainwater. Several linear alkane organic compounds were observed in the fogwater, representing the contributions from petroleum products at concentrations far

  6. 高速公路安全与交通流特征参数关系%Relationship Between Traffic Flow and Safety on Freeway

    Institute of Scientific and Technical Information of China (English)

    钟连德; 孙小端

    2013-01-01

    With 3-year' s traffic flow data and crash data of a freeway in plain terrain in China, the relationship between traffic flow and safety was analyzed. Besides the amount of traffic volume influences the crash occurrence absolutely, truck percent, the speed difference between truck and car, and the ratio of traffic volume to capacity are the most three prominent parameters. The interactive impact also existed among the traffic flow parameters inside, so how and to what extent the single parameter impacted the road safety was changeable, and some functions made sense only when other parameters were confined in the specific conditions. The authors developed several kinds of mathematical relationships that described the combined effects of traffic flow characteristics on crash occurrences, which can enable engineers to identify and implement effective countermeasures to reduce the probability of crashes.%基于我国平原区1条典型高速公路3年的事故数据和交通流数据对两者之间的关系进行了研究.利用多变量多项式比率等方法建立了多个交通流参数和事故率之间的关系方程,并辅以三维曲面图加以直观反映.研究表明:大车比例、大小车平均速度差和饱和度是影响交通安全最为重要的3个交通流特征参数,多个交通流参数之间相互作用关系复杂,单个参数对交通安全的影响随着其他参数取值的变化而变化.

  7. 基于粗糙集高速公路混沌T-SFNN控制仿真%Chaos Control Simulation of Freeway by Using T-S Fuzzy-neural Networks Based on Rough Sets

    Institute of Scientific and Technical Information of China (English)

    庞明宝; 贺国光; 赵新萍; 东方

    2012-01-01

    The on-ramp chaos control problem of freeway was studied by using fuzzy-neural networks based on rough set theory. Based on the uncertainty characteristic of vehicle volume in freeway system, the thought was proposed to establish the knowledge base of the on-ramp intelligent chaos controller of freeway by using data mining technology. The T-S fuzzy- neural networks ramp controller was designed. The traffic density, upstream traffic volume and maximal Lyapunov exponents are the input variables and the red timing is the output variable of the controller The knowledge base of the chaos controller was established by using rough sets theory. The controller structure including the extracting of fuzzy rules was determined. The parameters of the fuzzy controller were optimized by using fuzzy-neural networks. The feasibility and validity of the method was demonstrated via the simulation experiment, which shows that the order motion can be realized, the traffic jam phenomena can be suppressed, and the freeway capacity can be enhaned by using the intelligent chaos controller.%研究基于粗糙集理论的高速公路混沌系统模糊神经网络入口匝道控制方法。针对高速公路车流量不确定性特点,提出了通过教据挖掘技术建立交通流入口压道智能混沌控制器知识库的思想:设计了以密度、上游流量和最大李亚普诺走指数作为输入.红灯时间作为输出的T-S模糊神经网络混炖控制器;采用袒糙集理论建立混沌控制器知识库,确定模糊神经网络控制器结构并提取模糊规则;采用模糊神经网络方法对控制器参数进行优化。仿真结果表明:采用该方法设计的智能混沌控制器,可实现保持高速公路有序运动、避免交通堵塞、提高交通通行能力的目的,是提高高速公路管理控制水平的有效方法。

  8. Comparison of in situ observations of air traffic emission signatures in the North Atlantic flight corridor with simulations using a Gaussian plume model

    Energy Technology Data Exchange (ETDEWEB)

    Konopka, P.; Schlager, H.; Schulte, P.; Schumann, U.; Ziereis, H. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere; Hagen, D.; Whitefield, P. [Missouri Univ., Rolla, MO (United States). Lab. for Cloud and Aerosol Science

    1997-12-31

    Focussed aircraft measurements including NO, NO{sub 2}, O{sub 3}, and aerosols (CN) have been carried out over the Eastern North Atlantic as part of the POLINAT (Pollution from Aircraft Emissions in the North Atlantic Flight Corridor) project to search for small and large scale signals of air traffic emissions in the corridor region. Here, the experimental data measured at cruising altitudes on November, 6, 1994 close to peak traffic hours are considered. Observed peak concentrations in small scale NO{sub x} spikes exceed background level of about 50 pptv by up to two orders of magnitude. The measured NO{sub x} concentration field is compared with simulations obtained with a plume dispersion model using collected air traffic data and wind measurements. Additionally, the measured and calculated NO/NO{sub x} ratios are considered. The comparison with the model shows that the observed (multiple-)peaks can be understood as a superposition of several aircraft plumes with ages up to 3 hours. (author) 12 refs.

  9. Recent sea experience in South Africa and national principles: Learning from national scale SEAs for renewable energy and power corridors

    CSIR Research Space (South Africa)

    Lochner, Paul A

    2016-05-01

    Full Text Available Strategic Environmental Assessments (SEAs) for the development of wind and solar photovoltaic (PV) energy and powerline corridors have recently been completed in South Africa, leading to a decision by the South African Cabinet in February 2016...

  10. EAARL-B Topography—Big Thicket National Preserve: Little Pine Island Bayou Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first-surface topography Digital Surface Model (DSM) mosaic for the Little Pine Island Bayou Corridor Unit of Big Thicket National Preserve in Texas was produced...

  11. EAARL-B Topography—Big Thicket National Preserve: Canyonlands and Upper Neches River Corridor Units, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first-surface topography Digital Surface Model (DSM) mosaic for the Canyonlands and Upper Neches River Corridor Units of Big Thicket National Preserve in Texas was...

  12. EAARL-B Topography—Big Thicket National Preserve: Village Creek Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first-surface topography Digital Surface Model (DSM) mosaic for the Village Creek Corridor Unit of Big Thicket National Preserve in Texas was produced from...

  13. EAARL-B Topography—Big Thicket National Preserve: Canyonlands and Upper Neches River Corridor Units, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the Canyonlands and Upper Neches River Corridor Units of Big Thicket National Preserve in Texas was...

  14. EAARL-B Topography—Big Thicket National Preserve: Little Pine Island Bayou Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first-surface topography Digital Surface Model (DSM) mosaic for the Little Pine Island Bayou Corridor Unit of Big Thicket National Preserve in Texas was produced...

  15. EAARL-B Topography—Big Thicket National Preserve: Canyonlands and Upper Neches River Corridor Units, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the Canyonlands and Upper Neches River Corridor Units of Big Thicket National Preserve in Texas was...

  16. EAARL-B Topography—Big Thicket National Preserve: Little Pine Island Bayou Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the Little Pine Island Bayou Corridor Unit of Big Thicket National Preserve in Texas was produced...

  17. EAARL-B Topography—Big Thicket National Preserve: Little Pine Island Bayou Corridor Unit, Texas, 2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare-earth topography Digital Elevation Model (DEM) mosaic for the Little Pine Island Bayou Corridor Unit of Big Thicket National Preserve in Texas was produced...

  18. A small mammal community in a forest fragment, vegetation corridor and coffee matrix system in the Brazilian Atlantic forest.

    Directory of Open Access Journals (Sweden)

    Mariana Ferreira Rocha

    Full Text Available The objective of our work was to verify the value of the vegetation corridor in the conservation of small mammals in fragmented tropical landscapes, using a model system in the southeastern Minas Gerais. We evaluated and compared the composition and structure of small mammals in a vegetation corridor, forest fragments and a coffee matrix. A total of 15 species were recorded, and the highest species richness was observed in the vegetation corridor (13 species, followed by the forest fragments (10 and the coffee matrix (6. The absolute abundance was similar between the vegetation corridor and fragments (F = 22.94; p = 0.064, and the greatest differences occurred between the vegetation corridor and the matrix (F = 22.94; p = 0.001 and the forest fragments and the matrix (F = 22.94; p = 0.007. Six species showed significant habitat preference possibly related to the sensitivity of the species to the forest disturbance. Marmosops incanus was the species most sensitive to disturbance; Akodon montensis, Cerradomys subflavus, Gracilinanus microtarsus and Rhipidomys sp. displayed little sensitivity to disturbance, with a high relative abundance in the vegetation corridor. Calomys sp. was the species least affected by habitat disturbance, displaying a high relative abundance in the coffee matrix. Although the vegetation corridors are narrow (4 m width, our results support the hypothesis in which they work as a forest extension, share most species with the forest fragment and support species richness and abundance closer to forest fragments than to the coffee matrix. Our work highlights the importance and cost-effectiveness of these corridors to biodiversity management in the fragmented Atlantic Forest landscapes and at the regional level.

  19. Valuation of travel time savings for intercity travel: The Madrid-Barcelona corridor

    DEFF Research Database (Denmark)

    Roman, Concepcion; Carlos Martin, Juan; Espino, Raquel

    2014-01-01

    We derive values of travel time savings (VOT) for the Madrid-Barcelona corridor, linking the two largest cities in Spain, based on the estimation of discrete choice models among the main public transport services in the corridor: air transport, high speed rail (HSR) and bus. The new HSR alternative...... to provide useful information to quantify users' benefits during the lifespan of a given project. We found, as expected, that HSR and air transport users exhibit substantially higher values for saving travel time than bus travellers. Also as expected, savings of waiting time are more valued than savings...... (which started to operate in February 2008) competes directly with one of the densest airline domestic markets in the world, and its introduction produced substantial improvements in level of service, achieving reductions in travel time of more than 50% over the conventional train. A specifically...

  20. Polycyclic aromatic hydrocarbons (PAHs) in atmospheric dustfall from the industrial corridor in Hubei Province, Central China.

    Science.gov (United States)

    Zhang, Jiaquan; Qu, Chengkai; Qi, Shihua; Cao, Junji; Zhan, Changlin; Xing, Xinli; Xiao, Yulun; Zheng, Jingru; Xiao, Wensheng

    2015-10-01

    Thirty atmospheric dustfall samples collected from an industrial corridor in Hubei Province, central China, were analyzed for 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs) to investigate their concentrations, spatial distributions, sources, and health risks. Total PAH concentrations (ΣPAHs) ranged from 1.72 to 13.17 µg/g and averaged 4.91 µg/g. High molecular weight (4-5 rings) PAHs averaged 59.67% of the ΣPAHs. Individual PAH concentrations were not significantly correlated with total organic carbon, possibly due to the semi-continuous inputs from anthropogenic sources. Source identification studies suggest that the PAHs were mainly from motor vehicles and biomass/coal combustion. The incremental lifetime cancer risks associated with exposure to PAHs in the dustfall ranged from 10(-4) to 10(-6); these indicate potentially serious carcinogenic risks for exposed populations in the industrial corridor.

  1. Recent Positioning Techniques for Efficient Port Operations and Development of Suez Canal Corridor

    Directory of Open Access Journals (Sweden)

    Ahmed Elhattab

    2016-12-01

    Full Text Available The current developments in positioning techniques and communication technology have great impact on both construction and operations of ports. The majority of positioning systems for marine traffic are satellite based such as GPS. Virtual Reference Station is one of the recent high precision techniques for GNSS positioning which can be used for smart and efficient port.The advantages of using virtual reference station technique in different port operation and construction have been discussed in this paper. To apply this technique in Suez Canal corridor zone, a design of Continuously Operating Reference Station network has been proposed. This network can be utilized during different construction and operations phases of Suez Canal Corridor project.  

  2. Application of Transaction Costs in Analyzing Transport Corridors Using Multi-Agent-Based Simulation

    Directory of Open Access Journals (Sweden)

    Lawrence E. Henesey

    2006-03-01

    Full Text Available In analyzing the freight transportation systems, such as thetransport of intermodal containers, often direct monetary costsassociated with transportation are used to evaluate or determinethe choice of transport corridor. In forming decisions ontransport co"idor choice, this paper proposes that transactioncosts can be considered as an additional determinant in conductingtransport corridor analysis. The application of transactioncosts theory in analyzing the organizations and the transactionsthat occur, assists in indicating as to which governancestructure results in higher efficiencies. Efficiency is seen as eitherthe minimisation on costs or the maximisation of customerservice levels. The use of multi-agent based simulation for modellingthe organisational structure and mechanisms provides anovel approach in understanding the relationships in a regionaltransport co"idor.

  3. Tectonics of the Western Betics: the role of E-W strike slip fault corridors

    Science.gov (United States)

    Frasca, Gianluca; Gueydan, Frédéric; Brun, Jean-Pierre; Célérier, Bernard

    2014-05-01

    The tectonic origin of the arcuate Betic-Rif orogenic belt that surrounds the Alboran Sea at the western tip of the Mediterranean Sea remains debated. Here, we investigate the tectonic units cropping out in the Western Betics (Malaga region, Southern Spain) with the main goal of reconstructing the Oligo-Miocene evolution of the area. New structural data and geological mapping together with available data allow us to identify the main structural features of the area. Deformation is found to be extremely diffused but two E-W elongated tectonic blocks with different lithological composition are outlined by marked E-W dextral strike-slip corridors ending up in horse-tail splays. These E-W strike slip corridors are responsible for late Miocence tectonics of both the internal and external zones of the Betic Cordillera.

  4. North-South Corridor Demonstration Project: Ethical and Logistical Challenges in the Design of a Demonstration Study of Early Antiretroviral Treatment for Long Distance Truck Drivers along a Transport Corridor through South Africa, Zimbabwe, and Zambia

    Directory of Open Access Journals (Sweden)

    G. B. Gomez

    2013-01-01

    Full Text Available Background. Long-distance truck drivers are at risk of acquiring and transmitting HIV and have suboptimal access to care. New HIV prevention strategies using antiretroviral drugs to reduce transmission risk (early antiretroviral therapy (ART at CD4 count >350 cells/μL have shown efficacy in clinical trials. Demonstration projects are needed to evaluate “real world” programme effectiveness. We present the protocol for a demonstration study to evaluate the feasibility, acceptability, and cost of an early ART intervention for HIV-positive truck drivers along a transport corridor across South Africa, Zimbabwe, and Zambia, as part of an enhanced strategy to improve treatment adherence and retention in care. Methods and Analysis. This demonstration study would follow an observational cohort of truck drivers receiving early treatment. Our mixed methods approach includes quantitative, qualitative, and economic analyses. Key ethical and logistical issues are discussed (i.e., choice of drug regimen, recruitment of participants, and monitoring of adherence, behavioural changes, and adverse events. Conclusion. Questions specific to the design of tailored early ART programmes are amenable to operational research approaches but present substantial ethical and logistical challenges. Addressing these in demonstration projects can inform policy decisions regarding strategies to reduce health inequalities in access to HIV prevention and treatment programmes.

  5. Study on the oasis corridor landscape in the arid regions based on RS and GIS methods--application of Jinta Oasis, China

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The study on the oasis corridor landscape is a new hotspot in the ecological environment research in the arid regions.In oasis, maincorridor landscape types include river, ditch, shelterbelt and road.This paper introduces the basic ecological effects of the corridor landscapeon the transporting mass and energy and obstructing desert landscape expansion and incursion.Using Geographic Information System(GIS), wehave researched the corridor distribution and its spatial relationship with other landscape types in the Jinta Oasis.Based on the dynamicallymonitoring on the landscape pattern change of the Jinta Oasis during the latter 10 years by using Remote Sensing(RS) and GIS, the drivingfunctions of the corridors on this change have been analyzed in detail.The analysis results showed that all kinds of corridors' characteristics canbe quantified by the indexes such as length and width, ratio of perimeter and area, density and non-heterogeneity.The total corridor length ofJinta Oasis is 1838.5 km and its density is 2.1 km/km2 .The corridor density of the irrigation land, forest and resident area is maximal, whichshows that affection degree of the oasis corridors on them is the most.The improvement of the corridors quality is one of the important drivingfactors on the irrigation land and so on.The organic combination of the RS and GIS technologies and landscape research methods would be aneffective means for the corridor landscape research on arid region oasis.

  6. Designing Conservation Corridors in Production Landscapes: Assessment Methods, Implementation Issues, and Lessons Learned

    Directory of Open Access Journals (Sweden)

    Amanda T. Lombard

    2010-09-01

    Full Text Available Designing broad-scale conservation corridors has become increasingly common as a way of conducting an assessment for achieving targets for the representation and persistence of nature. However, since many of these corridors must traverse agricultural and other production landscapes, planning and implementation are not trivial tasks. Most approaches to conservation assessments in the dynamic world of production landscapes are data-intensive and analytically complex. However, in the real world, donor and other external requirements impose time and budget constraints, and dictate strong stakeholder involvement in the entire planning process. In order to accommodate this, assessments must be rapid, cheap, and the approach and products must be comprehensible and acceptable to stakeholders. Here we describe such an assessment aimed at identifying and implementing a network of conservation corridors in the Gouritz Initiative project domain of South Africa's Cape Floristic Region hotspot. We used empirical data and expert knowledge to identify a corridor network hypothesized to sustain key ecological and evolutionary processes. We also consulted experts to provide a spatially explicit assessment of the opportunity costs of conservation associated with agriculture, the predominant land use in the region. We used these products to identify categories of land requiring different actions and instruments to achieve conservation goals, thereby moving from the "where" to the "how" of conservation. This information was then fed into the collaborative strategy development process for the Gouritz Initiative. Our discussion emphasizes the lessons that we learnt from undertaking this assessment, particularly lessons regarding the implementation of the planning products. We conclude that at the outset of any planning project, a consensus on the vision must be achieved, a detailed social assessment of appropriate institutions must be undertaken, and a learning

  7. Walk the line: station context, corridor type and bus rapid transit walk access in Jinan, China

    OpenAIRE

    Jiang, Yang; Mehndiratta, Shomik; Zegras, P. Christopher

    2011-01-01

    This paper examines BRT station walk access patterns in rapidly urbanizing China and the relationship between bus rapid transit (BRT) station context and corridor type and the distance people will walk to access the system (i.e., catchment area). We hypothesize that certain contextual built environment features and station and right-of-way configurations will increase the walk-access catchment area; that is, that urban design influences users’ willingness to walk to BRT. We base our analysis ...

  8. ON THE FORMATION OF «ECONOMIC CORRIDOR SILK ROAD»: STATUS, PROBLEMS AND PROSPECTS

    Directory of Open Access Journals (Sweden)

    Rashid K. Alimov

    2013-01-01

    Full Text Available The author analyzes the status and prospect of Tajik-Chinese relations in the context of the initiative of the President of the PRC on establishing of an economic corridor the Silk Road. A detailed characteristic of expected challenges and benefits for countries of Central Asia and China is given. Special attention is spent on the possibilities of developing of relations between Tajikistan and China, that have risen to the level of strategic partnership.

  9. Migratory corridors of adult female Kemp’s ridley turtles in the Gulf of Mexico

    Science.gov (United States)

    Shaver, Donna J.; Hart, Kristen M.; Fujisaki, Ikuko; Rubio, Cynthia; Sartain-Iverson, Autumn R.; Pena, Jaime; Gamez, Daniel Gomez; Gonzales Diaz Miron, Raul de Jesus; Burchfield, Patrick M.; Martinez, Hector J.; Ortiz, Jaime

    2016-01-01

    For many marine species, locations of migratory pathways are not well defined. We used satellite telemetry and switching state-space modeling (SSM) to define the migratory corridor used by Kemp's ridley turtles (Lepidochelys kempii) in the Gulf of Mexico. The turtles were tagged after nesting at Padre Island National Seashore, Texas, USA from 1997 to 2014 (PAIS; n = 80); Rancho Nuevo, Tamaulipas, Mexico from 2010 to 2011 (RN; n = 14); Tecolutla, Veracruz, Mexico from 2012 to 2013 (VC; n = 13); and Gulf Shores, Alabama, USA during 2012 (GS; n = 1). The migratory corridor lies in nearshore Gulf of Mexico waters in the USA and Mexico with mean water depth of 26 m and a mean distance of 20 km from the nearest mainland coast. Migration from the nesting beach is a short phenomenon that occurs from late-May through August, with a peak in June. There was spatial similarity of post-nesting migratory pathways for different turtles over a 16 year period. Thus, our results indicate that these nearshore Gulf waters represent a critical migratory habitat for this species. However, there is a gap in our understanding of the migratory pathways used by this and other species to return from foraging grounds to nesting beaches. Therefore, our results highlight the need for tracking reproductive individuals from foraging grounds to nesting beaches. Continued tracking of adult females from PAIS, RN, and VC nesting beaches will allow further study of environmental and bathymetric components of migratory habitat and threats occurring within our defined corridor. Furthermore, the existence of this migratory corridor in nearshore waters of both the USA and Mexico demonstrates that international cooperation is necessary to protect essential migratory habitat for this imperiled species.

  10. Palaeohydrological corridors for hominin dispersals in the Middle East ∼250-70,000 years ago

    Science.gov (United States)

    Breeze, Paul S.; Groucutt, Huw S.; Drake, Nick A.; White, Tom S.; Jennings, Richard P.; Petraglia, Michael D.

    2016-07-01

    The timing and extent of palaeoenvironmental connections between northeast Africa, the Levant and the Arabian Peninsula during the Middle and Late Pleistocene are critical to debates surrounding dispersals of hominins, including movements of Homo sapiens out of Africa. Although there is evidence that synchronous episodes of climatic amelioration during the late Middle and Late Pleistocene may have allowed connections to form between northern Africa and western Asia, a number of palaeoclimate models indicate the continued existence of an arid barrier between northern Arabia and the Levant. Here we evaluate the palaeoenvironmental setting for hominin dispersals between, and within, northeast Africa and southwest Asia during Marine Isotope Stages (MIS) 7-5 using reconstructions of surface freshwater availability as an environmental proxy. We use remotely sensed data to map palaeohydrological features (lakes, wetlands and rivers) across the presently hyper-arid areas of northern Arabia and surrounding regions, integrating these results with palaeoclimate models, palaeoenvironmental proxy data and absolute dating to determine when these features were active. Our analyses suggest limited potential for dispersals during MIS 7 and 6, but indicate the formation of a palaeohydrological corridor (the 'Tabuk Corridor') between the Levant and the Arabian interior during the MIS 6-5e glacial-interglacial transition and during MIS 5e. A recurrence of this corridor, following a slightly different route, also occurred during MIS 5a. These palaeohydrological and terrestrial data can be used to establish when proposed routes for hominin dispersals became viable. Furthermore, the distribution of Arabian archaeological sites with affinities to Levantine assemblages, some of which are associated with Homo sapiens fossils, and the relative density of Middle Palaeolithic assemblages within the Tabuk Corridor, are consistent with it being utilised for dispersals at various times.

  11. Geometric Context and Orientation Map Combination for Indoor Corridor Modeling Using a Single Image

    Science.gov (United States)

    Baligh Jahromi, Ali; Sohn, Gunho

    2016-06-01

    Since people spend most of their time indoors, their indoor activities and related issues in health, security and energy consumption have to be understood. Hence, gathering and representing spatial information of indoor spaces in form of 3D models become very important. Considering the available data gathering techniques with respect to the sensors cost and data processing time, single images proved to be one of the reliable sources. Many of the current single image based indoor space modeling methods are defining the scene as a single box primitive. This domain-specific knowledge is usually not applicable in various cases where multiple corridors are joined at one scene. Here, we addressed this issue by hypothesizing-verifying multiple box primitives which represents the indoor corridor layout. Middle-level perceptual organization is the foundation of the proposed method, which relies on finding corridor layout boundaries using both detected line segments and virtual rays created by orthogonal vanishing points. Due to the presence of objects, shadows and occlusions, a comprehensive interpretation of the edge relations is often concealed. This necessitates the utilization of virtual rays to create a physically valid layout hypothesis. Many of the former methods used Orientation Map or Geometric Context to evaluate their proposed layout hypotheses. Orientation map is a map that reveals the local belief of region orientations computed from line segments, and in a segmented image geometric context uses color, texture, edge, and vanishing point cues to estimate the likelihood of each possible label for all super-pixels. Here, the created layout hypotheses are evaluated by an objective function which considers the fusion of orientation map and geometric context with respect to the horizontal viewing angle at each image pixel. Finally, the best indoor corridor layout hypothesis which gets the highest score from the scoring function will be selected and converted to a 3D

  12. Blood Parasites of Blue-winged Teal ( Anas discors ) from Two Migratory Corridors, in the Southern USA.

    Science.gov (United States)

    Garvon, Jason M; Mott, Joanna B; Jacobs, Sandy Serio; Fedynich, Alan M

    2016-07-01

    We collected 180 Blue-winged Teal ( Anas discors ) in September and October 2002 from Florida, US (n=100, representing the eastern migratory corridor) and the Louisiana-Texas, US, border (n=80, representing the western migratory corridor) and examined for blood parasites using thin heart-blood smears. Leucocytozoon simondi, Haemoproteus nettionis, and microfilariae were found in 16, 23, and 27 birds, respectively. Prevalence of L. simondi and H. nettionis did not vary by migratory corridor, but the prevalence of microfilariae was higher in the western corridor (23%) than the eastern corridor (9%). No differences in prevalence of L. simondi, H. nettionis, and microfilariae were observed by host age or sex. The mean density of L. simondi and H. nettionis averaged 1.5±0.3 and 2.3±0.4 (±SE per 3,000 erythrocytes), respectively. Ranked abundance models for main and interactive effects of corridor, age, and sex were not statistically significant for L. simondi or H. nettionis. Low prevalence and abundance of hematozoa in early autumn migrants reflects the likelihood of low exposure probabilities of Blue-winged Teal on the breeding grounds, compared to their congeners.

  13. Role of the future creative universities in the triple helix of science and technology corridors

    Directory of Open Access Journals (Sweden)

    Iraj nabipour

    2015-01-01

    Full Text Available The science and technology corridor is a complex cluster containing universities, science parks, research centers, high-tech companies, venture capital, institutional and physical infrastructures, and human capital in a defined geography with its unique management and legal structure in association with the business space and knowledge-based products. In fact, the science and technology corridor reflects the concept of development based on the knowledge region (the especial region for science and technology. The knowledge region is clearly a triple helix phenomenon par excellence: universities, governments and businesses combine their efforts to construct a common advantage which they would not be able to offer on their own. The future creative universities in connection with the knowledge city-regions not only will deal with innovation and entrepreneurial training but also produce a competitive, vibrant environment with high indices for quality of life and full of green technologies. In this article, we will present functional interactions of the creative universities in the triple helix, particularly the missions for the Iranian universities of medical sciences. As a theoretical model, the complex interactions of Bushehr University of Medical Sciences and Health Services with Bushehr Science and Technology Corridor will be discussed.

  14. Postglacial viability and colonization in North America’s ice-free corridor

    Science.gov (United States)

    Pedersen, Mikkel W.; Ruter, Anthony; Schweger, Charles; Friebe, Harvey; Staff, Richard A.; Kjeldsen, Kristian K.; Mendoza, Marie L. Z.; Beaudoin, Alwynne B.; Zutter, Cynthia; Larsen, Nicolaj K.; Potter, Ben A.; Nielsen, Rasmus; Rainville, Rebecca A.; Orlando, Ludovic; Meltzer, David J.; Kjær, Kurt H.; Willerslev, Eske

    2016-09-01

    During the Last Glacial Maximum, continental ice sheets isolated Beringia (northeast Siberia and northwest North America) from unglaciated North America. By around 15 to 14 thousand calibrated radiocarbon years before present (cal. kyr BP), glacial retreat opened an approximately 1,500-km-long corridor between the ice sheets. It remains unclear when plants and animals colonized this corridor and it became biologically viable for human migration. We obtained radiocarbon dates, pollen, macrofossils and metagenomic DNA from lake sediment cores in a bottleneck portion of the corridor. We find evidence of steppe vegetation, bison and mammoth by approximately 12.6 cal. kyr BP, followed by open forest, with evidence of moose and elk at about 11.5 cal. kyr BP, and boreal forest approximately 10 cal. kyr BP. Our findings reveal that the first Americans, whether Clovis or earlier groups in unglaciated North America before 12.6 cal. kyr BP, are unlikely to have travelled by this route into the Americas. However, later groups may have used this north-south passageway.

  15. Forest corridors maintain historical gene flow in a tiger metapopulation in the highlands of central India.

    Science.gov (United States)

    Sharma, Sandeep; Dutta, Trishna; Maldonado, Jesús E; Wood, Thomas C; Panwar, Hemendra Singh; Seidensticker, John

    2013-09-22

    Understanding the patterns of gene flow of an endangered species metapopulation occupying a fragmented habitat is crucial for landscape-level conservation planning and devising effective conservation strategies. Tigers (Panthera tigris) are globally endangered and their populations are highly fragmented and exist in a few isolated metapopulations across their range. We used multi-locus genotypic data from 273 individual tigers (Panthera tigris tigris) from four tiger populations of the Satpura-Maikal landscape of central India to determine whether the corridors in this landscape are functional. This 45 000 km(2) landscape contains 17% of India's tiger population and 12% of its tiger habitat. We applied Bayesian and coalescent-based analyses to estimate contemporary and historical gene flow among these populations and to infer their evolutionary history. We found that the tiger metapopulation in central India has high rates of historical and contemporary gene flow. The tests for population history reveal that tigers populated central India about 10 000 years ago. Their population subdivision began about 1000 years ago and accelerated about 200 years ago owing to habitat fragmentation, leading to four spatially separated populations. These four populations have been in migration-drift equilibrium maintained by high gene flow. We found the highest rates of contemporary gene flow in populations that are connected by forest corridors. This information is highly relevant to conservation practitioners and policy makers, because deforestation, road widening and mining are imminent threats to these corridors.

  16. Research on the quality of the wine grapes in corridor area of China

    Directory of Open Access Journals (Sweden)

    Guo Cheng

    2015-03-01

    Full Text Available The corridor area of Gansu Province is one of the most important wine grape growing regions in China, and this strip of land results in a significant difference in terms of terroir between its regions. Chemical composition and antioxidant capacity of the main wine grape varieties (Vitis vinifera L. cultivated in the corridor area of Gansu Province in northwest China were compared. Three regions (Zhangye, Wuwei, and Jiayuguan were selected to explain the influence of soil and climate conditions on the quality of wine grapes. This study aims to investigate the effect of different regions on berry composition and antioxidant capacity, providing a general evaluation of red and white wine grapes quality in the corridor area of China. The results showed that ‘Merlot’ grapes grown in Zhangye had the best quality among the different varieties in the three regions of Gansu evaluated. The moderate temperature and nitrogen deficiency were associated with improved fruit quality. It was identified that the most suitable grape variety from Zhangye is ‘Merlot’, and that ‘Cabernet Sauvignon’ and ‘Italian Resling’ are the most suitable varieties from Wuwei and Jiayuguan, respectively.

  17. Identifying ecological corridors for Amur tigers (Panthera tigris altaica) and Amur leopards (Panthera pardus orientalis).

    Science.gov (United States)

    Miquelle, Dale G; Rozhnov, Vyachaslav V; Ermoshin, Victor; Murzin, Andre A; Nikolaev, Igor G; Hernandez-Blanco, Jose A; Naidenko, Sergie V

    2015-07-01

    The rapid explosion of human populations and the associated development of human-dominated landscapes have drastically reduced and fragmented habitat for tigers (Panthera tigris) and leopards (Panthera pardus) across Asia, resulting in multiple small populations. However, Amur tiger (Panthera tigris altaica) habitat in Russia has remained largely interconnected, except for a break between tigers in southwest Primorye and the southern Sikhote-Alin Mountains. This habitat patch in southwest Primorye also retains the last population of Amur leopards (Panthera pardus orientalis). Genetic differentiation of tigers in southwest Primorye and the Sikhote-Alin Mountains along with survey data suggest that habitat fragmentation is limiting movement of tigers and leopards across the Razdolnaya River basin. We looked at historical and recent survey data on tigers and leopards and mapped existing cover types to examine land-use patterns of both large felids and humans in the development strip along the Razdolnaya River. We then used least-cost distance analyses to identify the most effective potential corridor to retain connectivity for large felids between Land of the Leopard National Park and Ussuriskii Zapovednik (Reserve). We identified a single potential corridor that still exists with a total distance of 62.5 km from Land of the Leopard National Park to Ussuriskii Zapovednik, mostly (93%) through forested habitat. We recommend formal recognition of a Razdolnaya ecological corridor and provide specific recommendations for each of 3 proposed management sections.

  18. Usage of Electric Vehicle Supply Equipment Along the Corridors between the EV Project Major Cities

    Energy Technology Data Exchange (ETDEWEB)

    Mindy Kirkpatrick

    2012-05-01

    The report explains how the EVSE are being used along the corridors between the EV Project cities. The EV Project consists of a nationwide collaboration between Idaho National Laboratory (INL), ECOtality North America, Nissan, General Motors, and more than 40 other city, regional and state governments, and electric utilities. The purpose of the EV Project is to demonstrate the deployment and use of approximately 14,000 Level II (208-240V) electric vehicle supply equipment (EVSE) and 300 fast chargers in 16 major cities. This research investigates the usage of all currently installed EV Project commercial EVSE along major interstate corridors. ESRI ArcMap software products are utilized to create geographic EVSE data layers for analysis and visualization of commercial EVSE usage. This research locates the crucial interstate corridors lacking sufficient commercial EVSE and targets locations for future commercial EVSE placement. The results and methods introduced in this research will be used by INL for the duration of the EV Project.

  19. Movements and corridors of African elephants in relation to protected areas

    Science.gov (United States)

    Douglas-Hamilton, I.; Krink, T.; Vollrath, F.

    2005-04-01

    Understanding how mammals satisfy their need for space in fragmenting ecosystems is crucial for ecosystem conservation. Using state-of-the-art global positioning system (GPS) technology we tracked 11 focal African elephants (Loxodonta africana) in Kenya at 3-hourly fix intervals and collected between 34 and 406 days per individual. Our recordings gave a high spatio-temporal resolution compared to previous studies and allowed novel insights into range use. The actual ranges of the tracked elephants are smaller than usually represented. Moreover, the ranges in our sample were complex and not confined to officially designated protected areas, except where fenced. All the unfenced elephants in our sample had distinct `home sectors' linked by `travel' corridors. Within each home sector the elephants concentrated in favourite `core zones'. Such core zones tended to lie in protected areas whereas corridors typically crossed unprotected range. Elephants moved significantly faster along corridors than elsewhere in their range, which suggests awareness of danger outside the protected area. We conclude that understanding the complex use of an animal's range is crucial for conservation planning aiming to balance animal interests with those of human beings that co-habit in their range.

  20. Planning for long, wide conservation corridors on private lands in the Oak Ridges Moraine, Ontario, Canada.

    Science.gov (United States)

    Whitelaw, Graham S; Eagles, Paul F J

    2007-06-01

    We explored the role of conservation biology in the planning of a natural-heritage system that includes long, wide conservation corridors situated primarily on private lands, and established to connect natural core areas in the Oak Ridges Moraine of Ontario, Canada. We based our review on government documents, semi-structured interviews with participants involved in this land-use planning process, and our involvement with the issue from 1990 through 2002. Conservation biology had a major influence on the outcome of the land-use planning process for this moraine. The landform was identified as an area of value by the environmental movement within the context of a number of ongoing government studies that began in the late 1980s and early 1990s. Conservation biologists and planners in government, the environmental movement, and the private sector carried out work related to conservation biology, including inventories and the development and application of criteria for the delineation of core areas and conservation corridors. Once the political timing was favorable (2001-2002), decision makers linked the science of conservation biology to planning policies and law in Ontario. The Oak Ridges Moraine land-use planning process was precedent setting in Canada, and possibly internationally. To our knowledge this is the first time long, wide conservation corridors on private lands were regulated through land-use-planning legislation and led to restrictions on urban development and aggregate resource extraction.

  1. Extreme endurance flights by landbirds crossing the Pacific Ocean: Ecological corridor rather than barrier?

    Science.gov (United States)

    Gill, R.E.; Tibbitts, T.L.; Douglas, D.C.; Handel, C.M.; Mulcahy, D.M.; Gottschalck, J.C.; Warnock, N.; McCaffery, B.J.; Battley, Phil F.; Piersma, Theunis

    2009-01-01

    Mountain ranges, deserts, ice fields and oceans generally act as barriers to the movement of land-dependent animals, often profoundly shaping migration routes. We used satellite telemetry to track the southward flights of bar-tailed godwits (Limosa lapponica baueri), shorebirds whose breeding and non-breeding areas are separated by the vast central Pacific Ocean. Seven females with surgically implanted transmitters flew non-stop 8117-11680km (10153??1043 s.d.) directly across the Pacific Ocean; two males with external transmitters flew non-stop along the same corridor for 7008-7390km. Flight duration ranged from 6.0 to 9.4 days (7.8??1.3 s.d.) for birds with implants and 5.0 to 6.6 days for birds with externally attached transmitters. These extraordinary non-stop flights establish new extremes for avian flight performance, have profound implications for understanding the physiological capabilities of vertebrates and how birds navigate, and challenge current physiological paradigms on topics such as sleep, dehydration and phenotypic flexibility. Predicted changes in climatic systems may affect survival rates if weather conditions at their departure hub or along the migration corridor should change. We propose that this transoceanic route may function as an ecological corridor rather than a barrier, providing a wind-assisted passage relatively free of pathogens and predators. ?? 2008 The Royal Society.

  2. The value of corridor in flat as place attachment in the life of the dwellers

    Science.gov (United States)

    Arifin, Lilianny; Widigdo, Wanda K.; Juniwati, Anik; Mintorogo, Danny

    2017-06-01

    Place attachment has been examined extensively in the behavioral and architecture studies over the past two decades. In the production of housing, designers mainly focus on the quality of the physical components. Place attachment is just the form of connection between a person and the environmental setting. However, it was challenging for this study to grasp the aspects of meanings and attachment, both in the level of personal, community and natural environment contexts, which are not adequately considered in the design process. In this study, three-dimensional model of personal and community attachments to their corridor in the flat was conceptually and empirically examined. The aim is to test an integrated approach to measuring place attachment at the corridor in flat in understanding the values of locations in the life of the dwellers. Sample cases included the examination of attachment to the hallway in three units located in Surabaya, Indonesia. It found out that the value of corridor as a place was affected by the daily experience of the places, social bonding, neighborhood interaction, and landscape values.

  3. Carpathian Shear Corridor - A strike-slip boundary of an extruded crustal segment

    Science.gov (United States)

    Marko, František; Andriessen, Paul A. M.; Tomek, Čestmír; Bezák, Vladimír; Fojtíková, Lucia; Bošanský, Marián; Piovarči, Milan; Reichwalder, Peter

    2017-04-01

    The Carpathian Shear Corridor (CSC), a morphostructurally distinctive ENE-WSW brittle shear zone, is a prominent dynamic interface of crustal fragments shifted during an oblique collision process combined with lateral extrusions in the Late stages of the Western Carpathians tectonic evolution. This tectonics was due to convection in the upper mantle, driven mainly by slab-pull forces related to a subductional process in front of prograding Carpathians. The CSC separates the marginal segment of the Western Carpathians, already firmly attached to the European plate, from the southern still eastwardly moving block. This process led to structural transpositions, anomalous rotation of small blocks and tilting and uplift/subsidence events, resulting in a tectonic style of horst and intramountaine basin alternations within the corridor. Preliminary paleomagnetic data indicate anomalous CCW block rotations within this corridor, and AFT ages indicate Early and Late Miocene (ca 24-22 Ma and ca 10-7 Ma) fault controlled exhumation events triggered by increased shear zone activity. Deep seismic sections, magnetotelluric and gravity data show that CSC follows a frontal ramp of the Western Carpathians thrust over the foreland. The CSC remains an active strike-slip shear zone, and therefore the most important earthquake risk-zone in the Slovakian portion of the Western Carpathians. It presents a lateral ramp transform boundary of eastwardly extruding crustal segment during the Miocene and up to the recent time.

  4. An editorial approach: Mike Nelson’s corridors and The Deliverance and The Patience

    Directory of Open Access Journals (Sweden)

    Helen Hughes

    2015-06-01

    Full Text Available This essay contrasts the contemporary British artist Mike Nelson’s approach to constructing his large, multi-room installations with his approach to editing the numerous artist books that he has produced since 2000. This comparison reveals several compositional symmetries between the two, namely pertaining to narrative non-linearity and meta-fictionality. The logic of montage is shown to similarly underscore both the books and the installations. This essay argues that the corridors connecting the different rooms of Nelson’s installations function in a similar way to the logic of montage: they play an integral role as the support that binds the structure of the installation (its multiple rooms together as a whole. This essay argues that the corridor is the primary viewing framework of the installation for the viewer, and that this vantage point is significant because the necessarily partial vision of the installation from the space of the corridor demonstrates the logic of installation art more broadly. I conclude by mapping the key compositional elements of Nelson’s artist books onto his installations, taking the 2001 work The Deliverance and The Patience as a case study, to show that the books do not exemplify the artwork as with traditional exhibition catalogues, but rather parallel it. That is, a structural continuity is established between these two facets of his work.

  5. Ray-Based Statistical Propagation Modeling for Indoor Corridor Scenarios at 15 GHz

    Directory of Open Access Journals (Sweden)

    Qi Wang

    2016-01-01

    Full Text Available According to the demands for fifth-generation (5G communication systems, high frequency bands (above 6 GHz need to be adopted to provide additional spectrum. This paper investigates the characteristics of indoor corridor channels at 15 GHz. Channel measurements with a vector network analyzer in two corridors were conducted. Based on a ray-optical approach, a deterministic channel model covering both antenna and propagation characteristic is presented. The channel model is evaluated by comparing simulated results of received power and root mean square delay spread with the corresponding measurements. By removing the impact of directional antennas from the transmitter and receiver, a path loss model as well as small-scale fading properties for typical corridors is presented based on the generated samples from the deterministic model. Results show that the standard deviation of path loss variation is related to the Tx height, and placing the Tx closer to the ceiling leads to a smaller fluctuation of path loss.

  6. Geospatial tools for the identification of a malaria corridor in Estado Sucre, a Venezuelan north-eastern state.

    Science.gov (United States)

    Delgado-Petrocelli, Laura; Camardiel, Alberto; Aguilar, Víctor Hugo; Martinez, Néstor; Córdova, Karenia; Ramos, Santiago

    2011-05-01

    Landscape ecology research relies on frameworks based on geographical information systems (GIS), geostatistics and spatial-feature relationships. With regard to health, the approach consists of systems analysis using a set of powerful tools aimed at the reduction of community vulnerability through improved public policies. The north-oriental malaria focus, one of five such foci in Venezuela, situated in the north-eastern part of the Estado Sucre state, unites several social and environmental features and functions as an epidemiological corridor, i.e. an endemic zone characterised by permanent interaction between the mosquito vector and the human host allowing a continuous persistence of the malaria lifecycle. A GIS was developed based on official cartography with thematic overlays depicting malaria distribution, socio-economic conditions, basic environmental information and specific features associated with the natural wetlands present in the area. Generally, malaria foci are continuously active but when the malaria situation was modelled in the north-oriental focus, a differential, spatio-temporal distribution pattern situation was found, i.e. a situation oscillating between very active and dormant transmission. This pattern was displayed by spatial and statistical analysis based on the model generated in this study and the results were confirmed by municipal and county malaria records. Control of malaria, keeping the incidence at a permanently low level within the regional population, should be possible if these results are taken into account when designing and implementing epidemiological surveillance policies.

  7. Geospatial tools for the identification of a malaria corridor in Estado Sucre, a Venezuelan north-eastern state

    Directory of Open Access Journals (Sweden)

    Laura Delgado-Petrocelli

    2011-05-01

    Full Text Available Landscape ecology research relies on frameworks based on geographical information systems (GIS, geostatistics and spatial-feature relationships. With regard to health, the approach consists of systems analysis using a set of powerful tools aimed at the reduction of community vulnerability through improved public policies. The north-oriental malaria focus, one of five such foci in Venezuela, situated in the north-eastern part of the Estado Sucre state, unites several social and environmental features and functions as an epidemiological corridor, i.e. an endemic zone characterised by permanent interaction between the mosquito vector and the human host allowing a continuous persistence of the malaria lifecycle. A GIS was developed based on official cartography with thematic overlays depicting malaria distribution, socio-economic conditions, basic environmental information and specific features associated with the natural wetlands present in the area. Generally, malaria foci are continuously active but when the malaria situation was modelled in the north-oriental focus, a differential, spatio-temporal distribution pattern situation was found, i.e. a situation oscillating between very active and dormant transmission. This pattern was displayed by spatial and statistical analysis based on the model generated in this study and the results were confirmed by municipal and county malaria records. Control of malaria, keeping the incidence at a permanently low level within the regional population, should be possible if these results are taken into account when designing and implementing epidemiological surveillance policies.

  8. Who wants to conserve remaining forest fragments in the Manompana Corridor?

    Directory of Open Access Journals (Sweden)

    Hans R. Felber

    2012-12-01

    locale, fournissant produits et services pour la consommation quotidienne ou donnant accès à un revenu monétaire. Sur un plan global, aussi bien les organisations de protection de la nature que les milieux scientifiques essayent d’endiguer la déforestation. Depuis les années 1996 la politique nationale à Madagascar a généré lois et processus visant à transférer la gestion des ressources forestières de l’Etat aux communautés locales. Cependant, il n’a pas été possible, jusqu’à ce jour, d’atténuer l’ampleur de la destruction et de la fragmentation des forêts pluviales de l’île. Plus encore, à l’heure actuelle la perception de l’importance des fragments de forêts n’est pas connue par la population. Un projet de recherche a été lancé pour contribuer à combler cette lacune, dans le corridor de Manompana, sur la côte. Les buts de ce projet étaient (i d’explorer l’importance des fragments de forêts pour les revenus monétaires de la population locale et (ii d’analyser la perception de l’importance des fragments de forêts par la population locale. Les recherches se sont déroulées dans quatre villages situés à des distances différentes du grand massif forestier. La population locale a été répartie en différentes catégories de niveau de vie et en fonction de la distance à parcourir entre les villages et la forêt. Cette approche a permis d’étudier le rôle de la forêt quant aux revenus monétaires des différents groupes de la population. Nous avons également cherché à établir un lien entre l’ampleur des revenus monétaires et un intérêt à conserver les fragments de forêts qui subsistent. Nos méthodes de recherche font recours à des exercices de « scoring », à des discussions avec des groupes ciblés et à des enquêtes de ménages. Il ressort des analyses que certains groupes ont un intérêt à conserver les fragments forestiers. Cet intérêt est significativement lié, d’une part, au

  9. Streamlining Transportation Corridor Planning Processess: Freight and Traffic Information

    Energy Technology Data Exchange (ETDEWEB)

    Franzese, Oscar [ORNL

    2010-08-01

    The traffic investigation is one of the most important parts of an Environmental Impact Statement of projects involving the construction of new roadway facilities and/or the improvement of existing ones. The focus of the traffic analysis is on the determination of anticipated traffic flow characteristics of the proposed project, by the application of analytical methods that can be grouped under the umbrella of capacity analysis methodologies. In general, the main traffic parameter used in EISs to describe the quality of traffic flow is the Level of Service (LOS). The current state of the practice in terms of the traffic investigations for EISs has two main shortcomings. The first one is related to the information that is necessary to conduct the traffic analysis, and specifically to the lack of integration among the different transportation models and the sources of information that, in general, reside in GIS databases. A discussion of the benefits of integrating CRS&SI technologies and the transportation models used in the EIS traffic investigation is included. The second shortcoming is in the presentation of the results, both in terms of the appearance and formatting, as well as content. The presentation of traffic results (current and proposed) is discussed. This chapter also addresses the need of additional data, in terms of content and coverage. Regarding the former, other traffic parameters (e.g., delays) that are more meaningful to non-transportation experts than LOS, as well as additional information (e.g., freight flows) that can impact traffic conditions and safety are discussed. Spatial information technologies can decrease the negative effects of, and even eliminate, these shortcomings by making the relevant information that is input to the models more complete and readily available, and by providing the means to communicate the results in a more clear and efficient manner. The benefits that the application and use of CRS&SI technologies can provide to

  10. Simulation approach to define sustainable balance between automobile traffic and bus rapid transit (BRT) in urban corridors

    Energy Technology Data Exchange (ETDEWEB)

    Siddique, A.J.; Khan, A. [Carleton Univ., Ottawa, ON (Canada). Dept. of Civil and Environmental Engineering

    2007-07-01

    One of the key challenges facing Central Business Districts (CBD) of medium size urban areas in North America is how to minimize the dependence on automobiles while providing efficient transit service. Underground facilities, exclusive bus/rail corridor or elevated roadways may not be practical due to high cost, aesthetics, noise and adverse land use effects. Because of its compatibility with land use and infrastructure, bus rapid transit (BRT) is receiving more attention. Existing roadway infrastructure, when used as a shared facility, may support rapid transit service besides providing a sustainable level of automobile traffic. A microscopic simulation approach is required in order to assess design changes and throughput levels of shared corridors. The purpose of this paper was to advance the concept of a sustainable balance between public transit and automobile traffic in the CBD, and demonstrate the role of microsimulation as a tool to analyze policies and designs. Limitations of the existing planning methodology were explained and a description of how microscopic simulation approach could be used to overcome methodological gaps was presented. In addition, selected results of a research study conducted using microscopic simulation approach for BRT corridors in Ottawa were shown. It was concluded that BRT operations under favourable conditions in downtown corridors can potentially serve over 28,000 passengers per hour and that removing on-street parking from bus transit corridor expedites bus movement. 12 refs., 5 tabs., 4 figs.

  11. Identifying Potential Conservation Corridors Along the Mongolia-Russia Border Using Resource Selection Functions: A Case Study on Argali Sheep

    Directory of Open Access Journals (Sweden)

    Buyanaa Chimeddorj

    2013-12-01

    Full Text Available The disruption of animal movements is known to affect wildlife populations, particularly large bodied, free-ranging mammals that require large geographic ranges to survive. Corridors commonly connect fragmented wildlife populations and their habitats, yet identifying corridors rarely uses data on habitat selection and movements of target species. New technologies and analytical tools make it possible to better integrate landscape patterns with spatial behavioral data. We show how resource selection functions can describe habitat suitability using continuous and multivariate metrics to determine potential wildlife movement corridors. During 2005–2010, we studied movements of argali sheep ( Ovis ammon near the Mongolia-Russia border using radio-telemetry and modeled their spatial distribution in relation to landscape features to create a spatially explicit habitat suitability surface to identify potential transboundary conservation corridors. Argali sheep habitat selection in western Mongolia positively correlated with elevation, ruggedness index, and distance to border. In other words, argali were tended use areas with higher elevation, rugged topography, and distances farther from the international border. We suggest that these spatial modeling approaches offer ways to design and identify wildlife corridors more objectively and holistically, and can be applied to many other target species.

  12. Bidirectional recovery patterns of Mojave Desert vegetation in an aqueduct pipeline corridor after 36 years: I. Perennial shrubs and grasses

    Science.gov (United States)

    Berry, Kristin H.; Weigand, James F.; Gowan, Timothy A.; Mack, Jeremy S.

    2015-01-01

    We studied recovery of 21 perennial plant species along a severely disturbed aqueduct corridor in a Larrea tridentata-Ambrosia dumosa plant alliance in the Mojave Desert 36 years after construction. The 97-m wide corridor contained a central dirt road and buried aqueduct pipeline. We established transects at 0 m (road verge), 20 m and 40 m into the disturbance corridor, and at 100 m in undisturbed habitat (the control). Although total numbers of shrubs per transect did not vary significantly with distance from the verge, canopy cover of shrubs, species richness, and species diversity were higher in the control than at the verge and other distances. Canopy cover of common shrubs (Ericameria nauseosa, Ambrosia salsola, A. dumosa, L. tridentata, Grayia spinosa) and perennial grasses (Elymus elymoides, Poa secunda) also varied significantly by location. Discriminant analysis clearly separated the four distances based on plant composition. Patterns of recovery were bidirectional: secondary succession from the control into the disturbance corridor and inhibition from the verge in the direction of the control. Time estimated for species composition to resemble the control is dependent on location within the disturbance corridor and could be centuries at the road verge. Our findings have applications to other deserts.

  13. Studi Hubungan Budaya dengan Aglomerasi Ekonomi (North-South Corridor Di Jawa Timur

    Directory of Open Access Journals (Sweden)

    Rachmad Kresna Sakti

    2012-05-01

    Full Text Available ABSTRACT   There are two things that commonly identify economic activitivities spacially such as concentration and imbalance.  East Java has two concentration poles of Java economic activities spacially. One of the concentration areas in East Java is in Surabaya, and that concentration activity is called North-South Corridor which is close to temple/ archeological site in East Java. Based on the fact, this research answers some questions like (1 Is there any interaction between culture dimension (the people and economic dimension? (2 How does culture dimension interacts with economic dimension? The aims of the research are (a To know the interaction between culture dimension (the people and economic dimension partially and cumulatively, so there will be North-South Corridor in East Java; (b To know the flow of mechanism from the detail of culture dimension interacting with economic dimension. The research was done outside North-South Corridor  area in East Java. The result of the research shows (1 there is a relationship between culture and economic dimension. It can be showed from the difference of each economic subject both inside and outside North-South Corridor in facing Hofstede Culture; (2 the difference of culture is formed by the environment of area inside and outside North-South Corridor.   Keywords: North-South Corridor, culture, economic concentration   ABSTRAKS   Terdapat dua hal yang seringkali menjadi ciri menonjol dari kegiatan perekonomian secara spasial, yaitu adanya konsentrasi dan ketimpangan. Di Pulau Jawa Terdapat dua kutub konsentrasi kegiatan ekonomi di Jawa secara spasial. Salah satunya wilayah konsentrasi kegiatan ekonomi di Surabaya Jawa Timur. Konsentrasi kegiatan tersebut dikenal dengan koridor utara – selatan. Menariknya koridor Utara-Selatan berhimpit dengan letak situs purbakala/candi di Jawa Timur.  Berpijak pada kesenjangan realita tersebut, penelitan ini berusaha menjawab pertanyaan berikut, (1 apakah

  14. Tectonic inversion of compressional structures in the Southern portion of the Paramirim Corridor, Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Simone Cerqueira Pereira Cruz

    Full Text Available The Paramirim Corridor represents the maximum inversion zone of the Paramirim Aulacogen. Reverse-to-reverse dextral shear zones and various types of folds dominate such corridor. These structures reflect a stress field that is WSW-ENE oriented, developed in units of Aulacogen basement, as well as in the Lagoa Real Intrusive Suite, of Statherian age, in Espinhaço and São Francisco supergroups, of Statherian-Tonian and Cryogenian ages, respectively, and in the Macaúbas-Santo Onofre Group, of Tonian age at the most. A rich collection of extensional structures truncate compressional structures of the Paramirim Corridor, characterized by normal shear zones and foliation, which is sometimes mylonitic, down-dip stretching lineation, drag folds, traction fractures and S/C structures. In these shear zones, quartz occurs truncated by the foliation, while feldspars are fractured and altered to white mica. Distribution of the quartz c-axes is at a maximum of 14° from the Z-axis. Thus, it suggests that the deformation activated mainly the basal glide planes in the direction. The paleostress study using the Win-Tensor software demonstrated that the regimen ranged between radial and pure distention. The S1 direction oscillated around a vertical trend, while s3 was sub-horizontal, with a predominant N230-050° direction. Ar-Ar ages in biotite obtained from the extensional shear zones ranged from 480 and 490 Ma. Together, data obtained for the structures associated with the late extensional regimen described in the present study suggest that its nucleation is associated with distal and brittle-ductile sectors of the gravitational collapse zone of Araçuaí-West Congo Orogen.

  15. Recreational trails as corridors for alien plants in the Rocky Mountains, USA

    Science.gov (United States)

    Wells, Floye H.; Lauenroth, William K.; Bradford, John B.

    2012-01-01

    Alien plant species often use areas of heavy human activity for habitat and dispersal. Roads and utility corridors have been shown to harbor more alien species than the surrounding vegetation and are therefore believed to contribute to alien plant persistence and spread. Recreational trails represent another corridor that could harbor alien species and aid their spread. Effective management of invasive species requires understanding how alien plants are distributed at trailheads and trails and how their dispersal may be influenced by native vegetation. Our overall goal was to investigate the distribution of alien plants at trailheads and trails in the Rocky Mountains of Colorado. At trailheads, we found that although the number of alien species was less than the number of native species, alien plant cover ( x̄=50%) did not differ from native plant cover, and we observed a large number of alien seedlings in the soil seed bank, suggesting that alien plants are a large component of trailhead communities and will continue to be so in the future. Along trails, we found higher alien species richness and cover on trail (as opposed to 4 m from the trail) in 3 out of 4 vegetation types, and we observed higher alien richness and cover in meadows than in other vegetation types. Plant communities at both trailheads and trails, as well as seed banks at trailheads, contain substantial diversity and abundance of alien plants. These results suggest that recreational trails in the Rocky Mountains of Colorado may function as corridors that facilitate the spread of alien species into wildlands. Our results suggest that control of alien plants should begin at trailheads where there are large numbers of aliens and that control efforts on trails should be prioritized by vegetation type.

  16. Normalizing and scaling of data to derive human response corridors from impact tests.

    Science.gov (United States)

    Yoganandan, Narayan; Arun, Mike W J; Pintar, Frank A

    2014-06-01

    It is well known that variability is inherent in any biological experiment. Human cadavers (Post-Mortem Human Subjects, PMHS) are routinely used to determine responses to impact loading for crashworthiness applications including civilian (motor vehicle) and military environments. It is important to transform measured variables from PMHS tests (accelerations, forces and deflections) to a standard or reference population, termed normalization. The transformation process should account for inter-specimen variations with some underlying assumptions used during normalization. Scaling is a process by which normalized responses are converted from one standard to another (example, mid-size adult male to large-male and small-size female adults, and to pediatric populations). These responses are used to derive corridors to assess the biofidelity of anthropomorphic test devices (crash dummies) used to predict injury in impact environments and design injury mitigating devices. This survey examines the pros and cons of different approaches for obtaining normalized and scaled responses and corridors used in biomechanical studies for over four decades. Specifically, the equal-stress equal-velocity and impulse-momentum methods along with their variations are discussed in this review. Methods ranging from subjective to quasi-static loading to different approaches are discussed for deriving temporal mean and plus minus one standard deviation human corridors of time-varying fundamental responses and cross variables (e.g., force-deflection). The survey offers some insights into the potential efficacy of these approaches with examples from recent impact tests and concludes with recommendations for future studies. The importance of considering various parameters during the experimental design of human impact tests is stressed.

  17. Colonisation trends of the invasive plant, Impatiens glandulifera, along river corridors: some preliminary findings

    Science.gov (United States)

    Greenwood, Phil; Kuhn, Brigitte; Kuhn, Nikolaus

    2016-04-01

    Originating from the Himalayas, the highly invasive plant, Impatiens glandulifera (Himalayan Balsam), is now found on three separate continents, with a distribution that includes most temperate European countries, large areas of east and west North America and parts of New Zealand. As a ruderal species, it prefers damp, shady and fertile soils that are frequently disturbed. This means that it commonly occurs along the riparian zone of rivers and streams. Being highly sensitivity to cold weather, however, whole stands suddenly and often simultaneously die-off; leaving riparian areas bare or partially devoid of vegetation. These lifecycle traits have implicated it in promoting soil erosion in affected river systems in temperate regions. Recent work undertaken by members of the Physical Geography & Environmental Change Research Group, University of Basel, has documented erosion rates along a section of contaminated river systems in northwest Switzerland, and southwest UK. Collectively, these data now span a total of seven separate germination and die-off cycles. Results from both river systems over all monitoring campaigns indicate that soil loss from areas contaminated with I. glandulifera is significantly greater than comparable areas supporting perennial vegetation. Crucially, however, extremely high-magnitude erosion was recorded at approximately 30% of contaminated areas (n=41). Reasons for high disturbance levels focus on the possibility that I. glandulifera tends to colonise depositional areas within a flood-zone. As those areas act as foci for the accretion of flood-derived sediment, the ability of this material to resist subsequent mobilisation processes is low due to limited cohesion, poor compaction and undeveloped soil structure. We hypothesis, therefore, that the tendency of I. glanduilfera to grow in depositional sites will be reflected in a number of key physico-chemical traits associated with soils in such areas; namely lower in-situ bulk

  18. Urban ventilation corridors mapping using surface morphology data based GIS analysis

    Science.gov (United States)

    Wicht, Marzena; Wicht, Andreas; Osińska-Skotak, Katarzyna

    2017-04-01

    This paper describes deriving the most appropriate method for mapping urban ventilation corridors, which, if properly designed, reduce heat stress, air pollution and increase air quality, as well as increase the horizontal wind speed. Urban areas are - in terms of surface texture - recognized as one of the roughest surfaces, which results in wind obstruction and decreased ventilation of densely built up areas. As urban heat islands, private household and traffic emissions or large scale industries occur frequently in many cities, both in temperate and tropical regions. A proper ventilation system has been suggested as an appropriate mitigation mean [1] . Two concepts of morphometric analyses of the urban environment are used on the example of Warsaw, representing a dense, urban environment, located in the temperate zone. The utilized methods include firstly a roughness mapping calculation [2] , which analyses zero plane displacement height (zd) and roughness length (z0) and their distribution for the eight (inter-)cardinal wind directions and secondly a grid-based frontal area index mapping approach [3] , which uses least cost path analysis. Utilizing the advantages and minimizing the disadvantages of those two concepts, we propose a hybrid approach. All concepts are based on a 3D building database obtained from satellite imagery, aided by a cadastral building database. Derived areas (ventilation corridors), that facilitate the ventilation system, should be considered by the local authorities as worth preserving, if not expanding, in order to improve the air quality in the city. The results also include designation of the problematic areas, which greatly obscure the ventilation and might be investigated as to reshape or rebuilt to introduce the air flow in particularly dense areas like city centers. Keywords: roughness mapping; GIS; ventilation corridors; frontal area index Rizwan, A. M., Dennis, L. Y., & Chunho, L. I. U. (2008). A review on the generation

  19. CHINA PAKISTAN ECONOMIC CORRIDOR (CPEC): PROSPECTS AND CHALLENGES FOR REGIONAL INTEGERATION

    OpenAIRE

    Ali, Akber

    2015-01-01

    As a flagship of China’s One Belt One Road initiative, China Pakistan Economic Corridor (CPEC) is pivotal to China’s energy security owing to the growing row in the region of South China Sea among China and other regional and global players. The ongoing contestation between China and other countries in the Asia Pacific has compelled China to look for alternative pathways to meet its increasing energy needs in case of any blockade of the Strait of Malacca as a consequence of any conflict betwe...

  20. Corridor of existence of thermodynamically consistent solution of the Ornstein-Zernike equation.

    Science.gov (United States)

    Vorob'ev, V S; Martynov, G A

    2007-07-14

    We obtain the exact equation for a correction to the Ornstein-Zernike (OZ) equation based on the assumption of the uniqueness of thermodynamical functions. We show that this equation is reduced to a differential equation with one arbitrary parameter for the hard sphere model. The compressibility factor within narrow limits of this parameter variation can either coincide with one of the formulas obtained on the basis of analytical solutions of the OZ equation or assume all intermediate values lying in a corridor between these solutions. In particular, we find the value of this parameter when the thermodynamically consistent compressibility factor corresponds to the Carnahan-Stirling formula.

  1. Comparison of serial and parallel simulations of a corridor fire using FDS

    Science.gov (United States)

    Valasek, L.

    2015-09-01

    Current fire simulators allow to model the course of fire in large areas and its impact on structure and equipment. This paper deals with a comparison of serial and parallel calculations of simulation of a corridor fire by the FDS (Fire Dynamics Simulator) system. In parallel case, the whole computational domain is divided into several computational meshes, the computation on each mesh is considered as a single MPI (Message Passing Interface) process realised on one computational core and communication between MPI processes is provided by MPI. The aim of this paper is to determine the size of error caused by parallelization of computation, which occurs at touches of computational meshes.

  2. Comparative use of riparian corridors and oases by migrating birds in southeast Arizona

    Science.gov (United States)

    Skagen, S.K.; Melcher, C.P.; Howe, W.H.; Knopf, F.L.

    1998-01-01

    The relative importance of cottonwood-willow riparian corridors and isolated oases to land birds migrating across southeastern Arizona was evaluated during four spring migrations, 1989 to 1994, based on patterns of species richness, relative abundance, density, and body condition of birds. We surveyed birds in 13 study sites ranging in size and connectivity from small isolated patches to extensive riparian forest, sampled vegetation and insects, and captured birds in mistnets. The continuous band of riparian vegetation along the San Pedro River does not appear to be functioning as a corridor for many migrating species, although it may for a few, namely Yellow-breasted Chats (Icteria virens), Summer Tanagers (Piranga rubra), and Northern Rough-winged Swallows (Steldigopteryx serripennis), which account for fewer than 10% of the individuals migrating through the area. Small, isolated oases hosted more avian species than the corridor sites, and the relative abundances of most migrating birds did not differ between sites relative to size-connectivity. There were few differences in between-year variability in the relative abundances of migrating birds between corridor and oasis sites. Between-year variability decreased with overall abundance of species and was greater for species with breeding ranges that centered north of 50??N latitude. Body condition of birds did not differ relative to the size-connectivity of the capture site, but individuals of species with more northerly breeding ranges had more body fat than species that breed nearby. Peak migration densities of several bird species far exceeded breeding densities reported for the San Pedro River, suggesting that large components of these species were en route migrants. Peak densities of Yellow Warblers (Dendroica petechia) reached 48.0 birds/ha, of Wilson's Warblers (Wilsonia pusilla) 33.7 birds/ha, and of Yellow-rumped Warblers (D. coronata) 30.1 birds/ha. Riparian vegetation is limited in extent in the

  3. A preliminary study on designing ecological corridors in Xishuangbanna National Nature Reserve with 3S techniques

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This paper is based on the fieldwork in Xishuang-banna Natioanl Nature Reserve in Yunnan Province of China. GPS data of Asian elephants were collected and analyzed with the remote sensing satellite photos of the region to estimate the landform physiognomy of different colors. We also analyzed a series of ecological factors includ-ing altitude, landform, relief, villages and roads which affected the distribution and movement of Asian elephants. The results suggested the possibility of designing and estab-lishing corridors in Xishuangbanna National Nature Reserve to protect the population of wild elephants in the region.

  4. Robust analysis of an underwater navigational strategy in electrically heterogeneous corridors.

    Science.gov (United States)

    Dimble, Kedar D; Ranganathan, Badri N; Keshavan, Jishnu; Humbert, J Sean

    2016-08-01

    Obstacles and other global stimuli provide relevant navigational cues to a weakly electric fish. In this work, robust analysis of a control strategy based on electrolocation for performing obstacle avoidance in electrically heterogeneous corridors is presented and validated. Static output feedback control is shown to achieve the desired goal of reflexive obstacle avoidance in such environments in simulation and experimentation. The proposed approach is computationally inexpensive and readily implementable on a small scale underwater vehicle, making underwater autonomous navigation feasible in real-time.

  5. GEOMETRIC CONTEXT AND ORIENTATION MAP COMBINATION FOR INDOOR CORRIDOR MODELING USING A SINGLE IMAGE

    Directory of Open Access Journals (Sweden)

    A. B. Jahromi

    2016-06-01

    Full Text Available Since people spend most of their time indoors, their indoor activities and related issues in health, security and energy consumption have to be understood. Hence, gathering and representing spatial information of indoor spaces in form of 3D models become very important. Considering the available data gathering techniques with respect to the sensors cost and data processing time, single images proved to be one of the reliable sources. Many of the current single image based indoor space modeling methods are defining the scene as a single box primitive. This domain-specific knowledge is usually not applicable in various cases where multiple corridors are joined at one scene. Here, we addressed this issue by hypothesizing-verifying multiple box primitives which represents the indoor corridor layout. Middle-level perceptual organization is the foundation of the proposed method, which relies on finding corridor layout boundaries using both detected line segments and virtual rays created by orthogonal vanishing points. Due to the presence of objects, shadows and occlusions, a comprehensive interpretation of the edge relations is often concealed. This necessitates the utilization of virtual rays to create a physically valid layout hypothesis. Many of the former methods used Orientation Map or Geometric Context to evaluate their proposed layout hypotheses. Orientation map is a map that reveals the local belief of region orientations computed from line segments, and in a segmented image geometric context uses color, texture, edge, and vanishing point cues to estimate the likelihood of each possible label for all super-pixels. Here, the created layout hypotheses are evaluated by an objective function which considers the fusion of orientation map and geometric context with respect to the horizontal viewing angle at each image pixel. Finally, the best indoor corridor layout hypothesis which gets the highest score from the scoring function will be selected

  6. Potential economic corridors between Vietnam and Lao PDR: Roles played by Vietnam

    OpenAIRE

    Nguyen, Binh Giang

    2012-01-01

    The Third Thai-Lao Friendship over the Mekong officially opened on 11th November 2011 facilitates the cross-border trade along Asian Highway 15 and Asian Highway 131 between Northeast Thailand, Central Lao PDR and North Central Vietnam. Since the establishment of East-West Economic Corridor (EWEC) which based on the Asian Highway 16, the cross-border trade among countries in Greater Mekong Sub-region has been much facilitated. The success of EWEC encourages local governments in the region to...

  7. Discriminant analysis based method to develop real-time crash indicator for evaluating freeway safety%基于判别分析的高速公路交通安全实时评价指标

    Institute of Scientific and Technical Information of China (English)

    徐铖铖; 刘攀; 王炜; 蒋璇

    2012-01-01

    To evaluate the impacts of changing traffic flow conditions on the risks of crash on freeways , a quantitative indicator based on real-time traffic flow data is developed to predict the occurrences of crash on freeways. Crash data and real-time traffic data with an interval of 30 s are extracted from a segment of the 1-880 N freeway in the state of California, United States. A linear combination of traffic flow parameters which is defined as real-time crash indicator is developed by Fisher discriminant analysis to identify dangerous traffic conditions. Negative real-time crash indicators represent dangerous traffic conditions potentially leading to crash occurrences while positive crash indicators represent normal traffic conditions which theoretically will not lead to crash occurrences. The conditional logistic regression model is applied to quantify the impacts of real-time crash indicator on the crash risk. The results show that the accuracy of using real-time crash indicator to predict crash occurrences on freeways is 65.7%. Moreover, one unit decrease in real-time crash indicator may increase the crash risk by 1. 8 times.%为了实时评价交通流变化对高速公路交通事故风险的影响,利用高精度交通流数据建立了高速公路交通安全实时评价指标.提取了美国加州I-880 N高速公路上采集间隔为30 s的实时交通流数据和事故数据,采用Fisher判别分析方法建立交通流参数的线性组合,以判别危险交通流状态.该线性组合被定义为高速公路交通安全实时评价指标,当该指标小于0时,代表危险交通流状态,有发生交通事故的风险;当该指标大于0时,代表正常交通流状态,没有发生交通事故的风险.采用条件logistic回归模型进一步研究了该指标与交通事故风险之间的定量关系.研究结果表明,该指标预测事故的精度为65.7%.另外,该指标每减小1个单位,交通事故风险将提高1.8倍.

  8. 高速公路入口匝道仿真模型参数校正研究%Study on Freeway On-ramp Simulation Model Parameters Calibration

    Institute of Scientific and Technical Information of China (English)

    朱庆瑞

    2016-01-01

    At present there are few researches on freeway on-ramp simulation model parameters calibration in China. This paper puts forward the highway on-ramp traffic simulation model parameters calibration process in China. First, the model default parameters are evaluated. If the default parameters don't satisfy the freeway on-ramp traffic simulation model parameters requirements, it is necessary to determine the calibration target and the calibration parameters. The calibration experiment is designed according to the determined parameters to be calibrated. Latin orthogonal experimental method is used to arrange the experiment scheme, to preliminarily calibrate the parameters, and several groups of ideal parameters combination are obtained. Then second calibration, fine-tuning of ideal combined parameters. Using T test method, the new parameter combination is calibrated again, to identify the ideal parameter combination which has the minimum error. Finally the model is verified. By methods of statistical validation and animation verification, the calibration parameters are verified, and to determine whether the calibration of parameters is in line with the freeway on-ramp traffic simulation model parameters. Taking the on-ramp traffic simulation model of a section of Huanghua–Shijiazhuang Expressway in Shijiazhuang as an example, the effectiveness of the freeway on-ramp simulation model parameters calibration is verified.%目前国内对高速公路入口匝道仿真模型的参数校正研究尚不多见。本文提出了我国高速公路入口匝道交通仿真模型参数校正流程。首先对模型默认参数进行评价,如不满足高速公路入口匝道交通仿真模型参数的要求,则需要进行校准指标及待校准参数的确定。根据确定的待校准参数设计校准实验,采用拉丁正交试验法安排实验方案,对参数进行初步校准,得出几组较为理想的参数组合。然后进行二次校准,对较理想的参

  9. Variable Speed Limit on Freeway Based on the Cost of Traffic Delay and Crash Damage%基于延误和事故损失的高速公路可变限速控制

    Institute of Scientific and Technical Information of China (English)

    王磊; 林永杰

    2016-01-01

    以交通检测系统获取的车道流量和速度为模型输入,分别提出基于延误损失、事故损失和综合损失等3类步进式可变限速控制。综合现有基于流量和基于车速离散性算法估计了高速公路事故发生率,提出了基于延误和事故发生率的路段综合损失计算方法。以青兰高速莱芜区约20 km的路段为实例,模拟了8组可变限速牌,通过微观仿真验证了提出的3种算法。结果证明,相比于静态控制,建立的3种模型均显著降低了主线车流的停车次数、停车延误和综合延误,改善了车辆行驶的平稳性,但主线车辆旅行时间略有增加。根据敏感性分析发现,随着驾驶员对限速值服从率的下降,可变限速控制的效益也逐渐降低,尤其低于80%时,下降显著;当低于60%时,基本保持不变。%Taking traffic volume and speed collected by traffic detection system as input variables, this paper proposes three kinds of step-by-step variable speed limit control models to minimize estimated delay cost, crash cost and comprehensive cost, respectively. The freeway crash rate is estimated based on volume-over-capacity and speed deviation by the existing model, and then the comprehensive cost is computed in terms of estimated delay and crash rate. In tests that used field freeway from about 20km segment of Qing-lan freeway with eight variable speed limit signs, these developed three controls show promise in reducing the numbers of vehicle stops, stopped delay and equivalent travel delay based on micro simulation results, smoothing traffic speed and improving traffic safety. Nevertheless, travel time of freeway vehicles is increased a little. Additionally, sensitivity analysis of driver compliance rate indicates that benefits of variable speed limit are gradually reduced as compliance rate decreased. When the compliance rate is below 80%, benefits are significantly decreased;and benefits are

  10. Chaos Control of Freeway Mainline Using Variable Speed Limits with FNN Based on Subtractive Clustering%基于减法聚类的高速公路主线可变速度FNN混沌控制

    Institute of Scientific and Technical Information of China (English)

    任沙沙; 庞明宝; 王彦虎; 陈培

    2012-01-01

    研究基于减法聚类的高速公路混沌系统主线可变速度模糊神经网络控制方法.针对交通系统的不确定性和非线性,提出了通过数据挖掘技术建立高速公路主线混沌控制器知识库的思想,简介了高速公路主线可变速度混沌控制原理,设计了以密度、上游车流量和最大李雅普诺夫指数作为输入,主线速度上限值作为输出的T-S模糊神经网络混沌控制器.采用减法聚类方法确定了控制器结构,包括提取模糊规则、产生控制器初始参数.使用遗传算法对聚类半径进行了优化,并采用模糊神经网络方法对控制器参数进行了优化.仿真结果表明:采用该方法设计的高速公路主线智能混沌控制器,可保持高速公路上的有序运动,从而达到抑制交通堵塞、提高道路通行能力的目的.%The chaos control of freeway mainline was studied by using variable speed limits and fuzzy-neural networks (FNN) based on subtractive clustering. Based on the uncertainty and nonlinearity of traffic system, the thought of establishing the knowledge base of mainline chaos controller for freeway by using data mining technology was proposed. Trie chaos control principle of mainline variable speed limits in freeway was briefly introduced. The T-S FNN chaos controller was designed, where traffic density, upstream traffic volume and maximal Lyapunov exponent were selected as the input variables and the mainline speed upper limit was selected as the output variable of the controller. Subtractive clustering was used to determine the controller structure, including the extracting of fuzzy rules and generating initial parameters. The radius of the clustering centers was optimized by genetic algorithm, and the parameters of the fuzzy controller were optimized by using fuzzy neural network. The simulation result indicates that order motion on freeway can be realized by using the mainline intelligent chaos controller designed by the

  11. Relationship between Level of Service and Traffic Safety on Freeway%高速公路交通服务水平与交通安全关系研究

    Institute of Scientific and Technical Information of China (English)

    张杰; 孙小端; 熊彬; 贺玉龙; 刘小明

    2012-01-01

    Level of service (LOS) is a quality measure describing operational conditions within a traffic stream. Traffic safety is not an index to be used to assess LOS. Based on the data of traffic flow and crashes of a freeway, the relationships between hourly LOS and traffic safety of segments in a representative day, and between LOS 15 minutes before a crash and traffic safety were studied. The level of casualty of crashes on different LOS was analyzed. The results show that with the improvement of LOS, the occurrence probability of an injury or fatal crash increases on the freeway and the crashes tend to be more serious.%交通服务水平是道路使用者从道路状况、交通条件、道路环境等方面可能得到的服务程度或服务质量,交通安全没有包括在评定交通服务水平的指标里.基于样本高速公路的交通流和交通事故数据,分析了路段1d24h每个小时的服务水平与交通安全的关系、每起事故发生前15 min的路段服务水平与交通安全的关系.通过比较各级交通服务水平下的交通伤亡事故水平,表明随着交通服务水平的提高,高速公路发生伤亡事故的机率也随之增加,交通事故后果越严重.

  12. Comparison of Placement Distances of Advance Guide Sign of Freeway Exit and Their Safety Performances%高速出口预告指路标志设置距离及其安全性能比较

    Institute of Scientific and Technical Information of China (English)

    郭唐仪; 胡启洲; 姚丁元

    2011-01-01

    为弥补我国现行规范和美国MUTCD关于出口预告指路标志设置经验主义的缺陷,根据驾驶员驶离高速主线的驾驶行为,视觉特性以及高速道路交通条件,建模确定了预告指路标志3种不同安装方式(路边直立式、路上横跨式及中央架设式)在不同车道数和不同设计速度下的设置距离.TSIS - CORSIM模拟表明,本文计算值比我国现行规范以及MUTCD推荐值在分流鼻上游500m产生的车道变换次数分别少38%和74%,能较大程度改善分流区的安全性能.%The current Chinese specification and US MUTCD guideline for placement distance of advance guide sign of freeway exit are empiricism-based. To remedy the existing shortcomings, considering drivers' exiting driving behaviors, vision characteristics and traffic conditions on freeway, the placement distances for ground installation, overhead installation and median installation under the condition of different lane numbers and design speeds were deduced by modeling. The simulation result in TIS-CORSIM indicates that the number of lane changes generated by the distance proposed in this paper is 40% less than that generated by current Chinese specification and 20% less than that from MUTCD guideline in diverging area from ramp nose to 500 m upstream. Thus, the recommended placement distances have better safety performance.

  13. The age of formation of the mirabilite and sand wedges in the Hexi Corridor and their paleoclimatic interpretation

    Institute of Scientific and Technical Information of China (English)

    WANG Nai'ang; ZHANG Jianming; CHENG Hongyi; GUO Jianying; ZHAO Qiang

    2003-01-01

    Sand wedges in the Hexi Corridor mainly formed in an alluvial gravel stratum of the late Pleistocene and the radiocarbon ages of the eolian sand infilling wedge prove that they were a product of the last ice age. During their period of formation, the mean annual air temperature in the Hexi Corridor was about -5.3℃, i. e. about 13℃ lower than that of the present. This estimated value iscoincident with the decrease in air temperature predicated from mirabilite (Na2SO4·10H2O) sedimentary layer in study area, and also agrees with research on theestimated amplitude of air temperature lowering in middle and high latitudes ofthe Northern Hemisphere during the last glacial period. The annual precipitation in the Western Hexi Corridor at that time was probably about 100-200 mm, i.e.about 100 mm more than at present.

  14. Structure and diversity of phyllostomid bat assemblages on riparian corridors in a human-dominated tropical landscape.

    Science.gov (United States)

    de la Peña-Cuéllar, Erika; Benítez-Malvido, Julieta; Avila-Cabadilla, Luis Daniel; Martínez-Ramos, Miguel; Estrada, Alejandro

    2015-02-01

    Tropical forests around the world have been lost, mainly because of agricultural activities. Linear elements like riparian vegetation in fragmented tropical landscapes help maintain the native flora and fauna. Information about the role of riparian corridors as a reservoir of bat species, however, is scanty. We assessed the value of riparian corridors on the conservation of phyllostomid bat assemblage in an agricultural landscape of southern Mexico. For 2 years (2011-2013), mist-netting at ground level was carried out twice during the dry season (December to May) and twice during the wet season (June to November) in different habitats: (1) riparian corridors in mature forest, (2) riparian corridors in pasture, (3) continuous forest away from riparian vegetation, and (4) open pastures. Each habitat was replicated three times. To determine the influence of vegetation structure on bat assemblages, all trees (≥10 cm dbh) were sampled in all habitats. Overall, 1752 individuals belonging to 28 species of Phyllostomidae were captured with Sternodermatinae being the most rich and abundant subfamily. Riparian corridors in mature forest and pastures had the greatest species richness and shared 65% of all species. Open pastures had the lowest richness and abundance of bats with no Phyllostominae species recorded. Six of the 18 species recorded could be considered as habitat indicators. There was a positive relationship between bat species composition and tree basal area. Our findings suggest that contrary to our expectations, bats with generalist habits and naturally abundant could be useful detector taxa of habitat modification, rather than bats strongly associated with undisturbed forest. Also in human-dominated landscapes, the maintenance of habitat elements such as large trees in riparian corridors can serve as reservoirs for bat species, especially for those that are strongly associated with undisturbed forest.

  15. Landform-Sediment Associations Within `Subglacial Meltwater Corridors' Reflect Channelised Subglacial Hydraulic Conditions During Deglaciation on the Canadian Shield

    Science.gov (United States)

    Haiblen, A. M.; Ward, B. C.; Campbell, J. E.; Normandeau, P. X.

    2016-12-01

    Esker networks have traditionally been invoked to represent the channelised subglacial drainage system in shield terrains. However, eskers are only one sediment-landform association found within `subglacial meltwater corridors': tracts where till has been eroded, bedrock is exposed and glaciofluvial sediments have been deposited in a time-transgressive manner. These regularly-spaced corridors parallel deglacial ice flow directions, have up-and-down profiles, and can cross modern drainage divides. Our LiDAR- and field-based mapping in the Slave and South Rae regions of Northwest Territories, west of the Keewatin Ice Divide, reveals that the most common sediment-landform association in many of these subglacial meltwater corridors is not eskers, but mounds and ridges that are up to 30 m high and 300 m wide. These mounds and ridges typically occur in groups of 20 to 200. Eskers have been observed to drape some mounds and ridges, thus, they must form subglacially. These mounds and ridges are commonly cored with diamicton that is similar in composition and structure to regional till. They are occasionally draped with well-sorted, stratified glaciofluvial sediments. The simplest interpretation for the genesis of these landforms is that regional till was eroded during meltwater corridor formation, after which glaciofluvial deposition occurred in some areas. The hydraulic conditions required to create these mounds and ridges are different to those required for esker formation. Thus, subglacial meltwater corridors, not just the eskers that they sometimes contain, should be considered when parameters are developed for numerical models relating to subglacial drainage systems in shield terrains. Determining the genesis of landforms found within meltwater corridors will improve our understanding of hydraulic conditions in the subglacial channelised drainage system during late-stage ice-sheet retreat and decay.

  16. A synthesis of hydrochemistry with an integrated conceptual model for groundwater in the Hexi Corridor, northwestern China

    Science.gov (United States)

    Wang, Liheng; Dong, Yanhui; Xu, Zhifang

    2017-09-01

    Although many studies have investigated the recharge and evolution of groundwater in the Hexi Corridor, northwestern (NW) China, they describe individual sites such as Jinchang, Jiuquan, Dunhuang, and others. Considering the similarity of these sites, a systematic review of the entire Hexi Corridor is lacking. This paper compares and summarizes previous studies in the Hexi Corridor to provide a regional perspective of the isotopic characteristics and hydrochemical composition of groundwater. In unconfined aquifers, groundwater is recharged by snow and ice melt water from the Qilian Mountains; local precipitation can be neglected. Therefore, the groundwater belongs to a unique hydrological cycle model in the Hexi Corridor, referred to as snow and ice melt water-groundwater system. The dominant anion species changes from HCO3- in front of the mountains to SO42- in the middle basin and Cl- at the basin boundary along the groundwater flow direction, and TDS increases gradually owing to evaporation. A major hydrogeochemical process is the dissolution of minerals from the aquifer in the recharge area changing to cation exchange reactions in the discharge area. Confined groundwater was recharged mainly in the late Pleistocene and middle Holocene at colder temperatures than those of modern times; thus, it is non-renewable. In addition to dissolution, the hydrochemical composition of confined groundwater is also affected by cation exchange reactions. The hydrogeochemical categories of the confined groundwater are simple and stable. In the present study, a conceptual model is established on the basis of the analyses presented, which has important implications for water resource management in the Hexi Corridor. The inter-basin water allocation program should continue in order to achieve optimal utilization of water resources, but groundwater exploitation should be limited as much as possible. Additionally, on the basis of the review and integration of previous research, the

  17. Endemic and threatened tetrapods in the restingas of the biodiversity corridors of Serra do Mar and of the central da Mata Atlântica in Eastern Brazil

    Directory of Open Access Journals (Sweden)

    C. F. D Rocha

    Full Text Available Biodiversity corridors comprise a mosaic of land uses connecting fragments of natural forest across a landscape. Two such corridors have been established along the eastern coast of Brazil: the Serra do Mar and the Central da Mata Atlântica corridors, along which most of the coastal plains are restinga areas. In this study, we analyze the present status of the endemic and endangered terrestrial vertebrates of both corridors. We sampled 10 restingas in both corridors, recording species of amphibians, reptiles, birds, and mammals. Some restingas harbor a relatively large number of endemic species, and two main regions of endemism can be identified along the restingas of both corridors: the coastal restingas from northern Espírito Santo State to southern Bahia State (between Linhares, ES, and Trancoso, BA, and the coastal region between the restingas of Maricá and Jurubatiba, Rio de Janeiro State. Six species of terrestrial vertebrates considered threatened with extinction are found in the restingas of Serra do Mar and Central da Mata Atlântica biodiversity corridors (Liolaemus lutzae, Formicivora littoralis, Mimus gilvus, Schistochlamys melanopis, and Trinomys eliasi. The region located between the restinga of Maricá and that of Jurubatiba is of special relevance for the conservation of vertebrate species of the restingas of the corridors because a considerable number of threatened species of terrestrial vertebrates are found there. We strongly recommend efforts to develop checklists of threatened faunas for the States of Espírito Santo and Bahia.

  18. Earthquake scenario and probabilistic ground-shaking hazard maps for the Albuquerque-Belen-Santa Fe, New Mexico, corridor

    Science.gov (United States)

    Wong, I.; Olig, S.; Dober, M.; Silva, W.; Wright, D.; Thomas, P.; Gregor, N.; Sanford, A.; Lin, K.-W.; Love, D.

    2004-01-01

    New Mexico's population is concentrated along the corridor that extends from Belen in the south to Española in the north and includes Albuquerque and Santa Fe. The Rio Grande rift, which encompasses the corridor, is a major tectonically, volcanically, and seismically active continental rift in the western U.S. Although only one large earthquake (moment magnitude (M) ≥ 6) has possibly occurred in the New Mexico portion of the rift since 1849, paleoseismic data indicate that prehistoric surface-faulting earthquakes of M 6.5 and greater have occurred on aver- age every 400 yrs on many faults throughout the Rio Grande rift.

  19. Retroperitoneal oblique corridor to the L2-S1 intervertebral discs in the lateral position: an anatomic study.

    Science.gov (United States)

    Davis, Timothy T; Hynes, Richard A; Fung, Daniel A; Spann, Scott W; MacMillan, Michael; Kwon, Brian; Liu, John; Acosta, Frank; Drochner, Thomas E

    2014-11-01

    Access to the intervertebral discs from L2-S1 in one surgical position can be challenging. The transpsoas minimally invasive surgical (MIS) approach is preferred by many surgeons, but this approach poses potential risk to neural structures of the lumbar plexus as they course through the psoas. The lumbar plexus and iliac crest often restrict the L4-5 disc access, and the L5-S1 level has not been a viable option from a direct lateral approach. The purpose of the present study was to investigate an MIS oblique corridor to the L2-S1 intervertebral disc space in cadaveric specimens while keeping the specimens in a lateral decubitus position with minimal disruption of the psoas and lumbar plexus. Twenty fresh-frozen full-torso cadaveric specimens were dissected, and an oblique anatomical corridor to access the L2-S1 discs was examined. Measurements were taken in a static state and with mild retraction of the psoas. The access corridor was defined at L2-5 as the left lateral border of the aorta (or iliac artery) and the anterior medial border of the psoas. The L5-S1 corridor of access was defined transversely from the midsagittal line of the inferior endplate of L-5 to the medial border of the left common iliac vessel and vertically to the first vascular structure that crosses midline. The mean access corridor diameters in the static state and with mild psoas retraction, respectively, were as follows: at L2-3, 18.60 mm and 25.50 mm; at L3-4, 19.25 mm and 27.05 mm; and at L4-5, 15.00 mm and 24.45 mm. The L5-S1 corridor mean values were 14.75 mm transversely, from midline to the left common iliac vessel and 23.85 mm from the inferior endplate of L-5 cephalad to the first midline vessel. The oblique corridor allows access to the L2-S1 discs while keeping the patient in a lateral decubitus position without a break in the table. Minimal psoas retraction without significant tendon disruption allowed for a generous corridor to the disc space. The L5-S1 disc space can be

  20. Environmental management model for small dairies in the Industrial Corridor of Boyaca (Colombia

    Directory of Open Access Journals (Sweden)

    Deháquiz Mejía Janneth Esperanza

    2012-04-01

    Full Text Available

    This research addresses the general objective of environmental issues, focusing on the Environmental Management System model that can be applied to small businesses in the dairy industry in the Industrial Corridor of Boyaca, for which the Environmental Management Model based on the NTC ISO 14000 Standard was created. This is a case study of 10 small dairy companies legally established in the study area. The research results are presented initially with a description of the context and specific means of dairy production activity in the Industrial Corridor of Boyaca; a situational diagnosis was performed for the dairy chain of the department, and likewise the study configured the profile and characterization of the administration and environment of these companies in the study area, using the information collected through a survey of the businesses as the input. With the information obtained in the diagnosis, the Environmental Management Model for these organizations was designed.

  1. Simulation of bidirectional pedestrian flow in transfer station corridor based on multi forces

    Institute of Scientific and Technical Information of China (English)

    周雪梅; 纪翔峰; 黄凰; 杨晓光

    2014-01-01

    A good understanding of pedestrian movement in the transfer corridor is vital for the planning and design of the station, especially for efficiency and safety.A multi-force vector grid model was presented to simulate the movement of bidirectional pedestrian flow based on cellular automata and forces between pedestrians. The model improves rule-based characteristics of cellular automata, details forces between pedestrians and solves pedestrian collisions by a several-step updating method to simulate pedestrian movements. Two general scenarios in corridor were simulated. One is bidirectional pedestrian flow simulation with isolation facility, and the other is bidirectional pedestrian flow simulation without isolation facility, where there exists disturbance in the middle. Through simulation, some facts can be seen that pedestrians in the case with isolation facility have the largest speed and pedestrians in the case without isolation facility have the smallest speed; pedestrians in the case of unidirectional flow have the largest volume and pedestrians in the case of without isolation facility have the smallest volume.

  2. Ecology of anopheline mosquitoes (Diptera: Culicidae) in the Central Atlantic Forest Biodiversity Corridor, southeastern Brazil.

    Science.gov (United States)

    Da Silva, Kleber S; Pinto, Israel De S; Leite, Gustavo R; Das Virgens, Thieres M; Dos Santos, Claudiney B; Falqueto, Aloísio

    2013-01-01

    Knowledge of the fauna composition of anopheline mosquitoes, their ecological aspects and behavior, and influence of climatic variables on their population dynamics can help in understanding the transmission of Plasmodium parasites and thus develop more efficient strategies for the control of malaria. In the Central Atlantic Forest Biodiversity Corridor, southeastern Brazil, foci of introduced malaria have been reported among people returning from the Amazon region, north Brazil. Our objective was to evaluate and compare the anopheline fauna from a preserved environment and an adjacent peridomiciliary modified environment at the Central Atlantic Forest Biodiversity Corridor. We collected anopheline mosquitoes on a monthly basis from June 2004 to May 2006 from both these environments to understand the ecological aspects and their association with the occurrence of malaria. We captured 5,491 anopheline mosquitoes belonging to two subgenera and 11 species and studied the correlations between anopheline mosquito species and climatic variables. We considered Anopheles darlingi (Root) as the principal malaria vector and Anopheles albitarsis s. l. (Arribalzaga) as the secondary vector.

  3. Anthropogenic influences on macro-level mammal occupancy in the Appalachian Trail corridor.

    Directory of Open Access Journals (Sweden)

    Peter L Erb

    Full Text Available Anthropogenic effects on wildlife are typically assessed at the local level, but it is often difficult to extrapolate to larger spatial extents. Macro-level occupancy studies are one way to assess impacts of multiple disturbance factors that might vary over different geographic extents. Here we assess anthropogenic effects on occupancy and distribution for several mammal species within the Appalachian Trail (AT, a forest corridor that extends across a broad section of the eastern United States. Utilizing camera traps and a large volunteer network of citizen scientists, we were able to sample 447 sites along a 1024 km section of the AT to assess the effects of available habitat, hunting, recreation, and roads on eight mammal species. Occupancy modeling revealed the importance of available forest to all species except opossums (Didelphis virginiana and coyotes (Canis latrans. Hunting on adjoining lands was the second strongest predictor of occupancy for three mammal species, negatively influencing black bears (Ursus americanus and bobcats (Lynx rufus, while positively influencing raccoons (Procyon lotor. Modeling also indicated an avoidance of high trail use areas by bears and proclivity towards high use areas by red fox (Vulpes vulpes. Roads had the lowest predictive power on species occupancy within the corridor and were only significant for deer. The occupancy models stress the importance of compounding direct and indirect anthropogenic influences operating at the regional level. Scientists and managers should consider these human impacts and their potential combined influence on wildlife persistence when assessing optimal habitat or considering management actions.

  4. Making climate change tangible for strategic adaptation planning: The Climate Corridor Approach

    Science.gov (United States)

    Orlowsky, Boris; Calanca, Pierluigi; Ali, Irshad; Ali, Jawad; Elguera Hilares, Agustin; Huggel, Christian; Khan, Inamullah; Neukom, Raphael; Nizami, Arjumand; Qazi, Muhammad Abbas; Robledo, Carmenza; Rohrer, Mario; Salzmann, Nadine; Schmidt, Kaspar

    2017-04-01

    Climate change is a global phenomenon and difficult to grasp. Although its importance is generally acknowledged, impacts of (future) climate change on human activities are in many cases not taken into account explicitly, in particular when planning development projects. This is due to technical and conceptual challenges, missing financial and human resources and competing priorities. Neglecting climate change can become problematic, if a proposed activity requires specific climatological conditions under which it becomes feasible, a simple example being crop cultivation that needs certain temperature an d precipitation ranges. Comparing such ``climate corridors'' to future climate projections provides an intuitive and low-cost yet quantitative means for assessing needs for, and viability of, adaptation activities under climate change - a "poor man's approach" to climate suitability analysis. A chief advantage of this approach is its modest demand on data. Three case studies from Pakistan, Peru and Tajikistan show that climate corridor analysis can deliver robust results and can be used to efficiently communicate risks and challenges of climate change to partners and stakeholders in the developing countries.

  5. Noise monitoring and modeling on four lanning of national highways corridor.

    Science.gov (United States)

    Devi, P Shiyamala; Rosaline, G Vimala

    2012-10-01

    Noise emitted from traffic contributes to about 55% of total noise pollution in India. This paper is an effort of a research conducted to quantify and analyze the traffic noise emissions along the Salem-Namakkal NH 7 corridor with an ultimate objective of setting up a traffic noise model based on the traffic noise conditions of Indian cities. Noise levels and other variables have been measured in 15 locations to develop a statistical regression model based on A-weighted equivalent noise level for Indian road conditions. The ambient noise levels recorded represent the higher noise levels prevailing along the NH 7 corridor. The Receptor Oriented Technique adopted proves to be helpful in characterizing the ambient noise levels along the study area. The newly developed road traffic noise model can be effectively used as a decision support tool for predicting equivalent noise levels in the cities of India. The present analysis also reveals that the magnitude of noise levels has an increasing trend due to the increased traffic flow and presents the attention needed for minimization. The mitigation measures and the future evaluations are discussed.

  6. Common raven occurrence in relation to energy transmission line corridors transiting human-altered sagebrush steppe

    Science.gov (United States)

    Coates, Peter S.; Howe, Kristy B.; Casazza, Michael L.; Delehanty, David J.

    2014-01-01

    Energy-related infrastructure and other human enterprises within sagebrush steppe of the American West often results in changes that promote common raven (Corvus corax; hereafter, raven) populations. Ravens, a generalist predator capable of behavioral innovation, present a threat to many species of conservation concern. We evaluate the effects of detailed features of an altered landscape on the probability of raven occurrence using extensive raven survey (n= 1045) and mapping data from southern Idaho, USA. We found nonlinear relationships between raven occurrence and distances to transmission lines, roads, and facilities. Most importantly, raven occurrence was greater with presence of transmission lines up to 2.2 km from the corridor.We further explain variation in raven occurrence along anthropogenic features based on the amount of non-native vegetation and cover type edge, such that ravens select fragmented sagebrush stands with patchy, exotic vegetative introgression. Raven occurrence also increased with greater length of edge formed by the contact of big sagebrush (Artemisia tridentate spp.) with non-native vegetation cover types. In consideration of increasing alteration of sagebrush steppe, these findings will be useful for planning energy transmission corridor placement and other management activities where conservation of sagebrush obligate species is a priority.

  7. EIA BASED COMPARATIVE URBAN TRAFFIC NOISE ANALYSIS BETWEEN OPERATIONAL AND UNDER CONSTRUCTION PHASE PUBLIC TRANSPORT CORRIDOR

    Directory of Open Access Journals (Sweden)

    Rajeev Kumar Mishra

    2014-09-01

    Full Text Available Delhi has a population of 16.75 million and is increasing at a rapid rate. This increase in population has enhanced the need for public transport. In Delhi, this need for public transport is served mainly by buses, auto rickshaws, a rapid transit system, taxis and suburban railways. Delhi has one of the highest road densities in India. Buses are the most popular means of transport catering to about 60% of the total demand. In order to meet the transport demand in Delhi, the State and the Union government started the construction of a mass rapid transit system, including the Delhi Metro. By the application of various data and public response, the paper accentuates the qualitative discussion on impacts of mass rapid transit system (MRTS corridor on land use and social aspects of lives of residents and road users. It also proposes certain mitigating measures for that meticulous condition. The analysis and survey outcome explain about the exceeded level of noise level as compared to CPCB standards. The share of public transport in total noise pollution is smaller than private but still exceeds the standards. Such problem demands the design of noise barrier along the corridor to curb the noise pollution.

  8. Typology of building shading elements on Jalan Sudirman corridor in Pekanbaru

    Science.gov (United States)

    Faisal, G.; Aldy, P.

    2016-04-01

    In 2013, temperature in Pekanbaru was between 22.60°C and 34.6°C with humidity 79.14 percent. This condition has increase the concern of energy utilization to building comfort. Buildings have the biggest energy consuming due to the use of air conditioner in Pekanbaru. One effort to reduced energy is shading devices application. Application of air conditioner need huge energy, replaced natural circulation with architecture elements to reduced building thermal. This research study about system and building shading devices types that influence building thermal in Pekanbaru so that knowing characteristics and elements form. This study aims to determine and identify of systems and building elements types in Pekanbaru, which the element forms to conquer in climate condition. Qualitative method with rationalistic-paradigm has used to identify typology of building shading devices on Jalan Sudirman corridor. The research orientation on typology theory, thermal theory, and building shading device to identification of building shading device types on Jalan Sudirman corridor. Based on the survey result, there are 2 type of building shading devices on Jalan Sudirman Pekanbaru which is based on forms and quantity of shading. The types are building shading devices based on shading quantity and building shading devices based on shading forms.

  9. REDUCING SURFACE TEMPERATURES OF NORTH-SOUTH BUSINESS CORRIDORS IN YOGYAKARTA

    Directory of Open Access Journals (Sweden)

    Prasasto SATWIKO

    2015-12-01

    Full Text Available The heat island has made the warm-humid climate city of Yogyakarta thermally more uncomfortable, which induces its people to depend more on energy consuming air conditioners. Business corridors are constructed from building walls and roofs, pedestrian paths, the streets and the vegetation, which convert solar radiation into heat. Infrared mappings of the four north-south axis business corridors of Yogyakarta found that streets and vehicles have their temperatures higher than the air temperature. Exception is at Gejayan St., where the street’s temperature is close to the air temperature. This street has rows of trees on its median, which effectively shades the street. Further study on Gejayan St. using a computer simulation method confirms that columnar and spreading form trees can reduce incident solar radiation on the street surface by, respectively, 13.35% and 22.02%. Putting creeping plants on pergolas reduce incident solar radiation on the west and the east walls by, respectively, 37.05% and 37.45%.

  10. Slovenian and European legal stipulations concerning protection and rehabilitation of river corridors

    Directory of Open Access Journals (Sweden)

    Matjaž Mikoš

    2003-01-01

    Full Text Available In view of the state of hydromorphological preservation of river corridors in the Slovenian hydrographic network and because of demands imposed by domestic and European legislature concerning water resource management and environmental protection, certain sections of rivers and streams that were for various reasons regulated in the past, will have to be rehabilitated. Permanent solutions to such issues demand careful planning of rehabilitation on suitable sections of rivers and streams, adequate positioning within physical planning acts, as well as streamlined administrative procedures and devised maintenance of rehabilitation areas. Because the process demands the return of formerly taken water surfaces into the domain of water ecosystems and dynamics of hydromorphological processes, and consequentially maintenance of regained surfaces, the public becomes an important factor, which is a position, granted by domestic and European laws. Last, but not least, successful execution of rehabilitation of water corridors, besides planning, administration and consistent public participation, demands knowledge about good practices of project management, as well as technical execution of such projects.

  11. Automated Inspection of Power Line Corridors to Measure Vegetation Undercut Using Uav-Based Images

    Science.gov (United States)

    Maurer, M.; Hofer, M.; Fraundorfer, F.; Bischof, H.

    2017-08-01

    Power line corridor inspection is a time consuming task that is performed mostly manually. As the development of UAVs made huge progress in recent years, and photogrammetric computer vision systems became well established, it is time to further automate inspection tasks. In this paper we present an automated processing pipeline to inspect vegetation undercuts of power line corridors. For this, the area of inspection is reconstructed, geo-referenced, semantically segmented and inter class distance measurements are calculated. The presented pipeline performs an automated selection of the proper 3D reconstruction method for on the one hand wiry (power line), and on the other hand solid objects (surrounding). The automated selection is realized by performing pixel-wise semantic segmentation of the input images using a Fully Convolutional Neural Network. Due to the geo-referenced semantic 3D reconstructions a documentation of areas where maintenance work has to be performed is inherently included in the distance measurements and can be extracted easily. We evaluate the influence of the semantic segmentation according to the 3D reconstruction and show that the automated semantic separation in wiry and dense objects of the 3D reconstruction routine improves the quality of the vegetation undercut inspection. We show the generalization of the semantic segmentation to datasets acquired using different acquisition routines and to varied seasons in time.

  12. AUTOMATED INSPECTION OF POWER LINE CORRIDORS TO MEASURE VEGETATION UNDERCUT USING UAV-BASED IMAGES

    Directory of Open Access Journals (Sweden)

    M. Maurer

    2017-08-01

    Full Text Available Power line corridor inspection is a time consuming task that is performed mostly manually. As the development of UAVs made huge progress in recent years, and photogrammetric computer vision systems became well established, it is time to further automate inspection tasks. In this paper we present an automated processing pipeline to inspect vegetation undercuts of power line corridors. For this, the area of inspection is reconstructed, geo-referenced, semantically segmented and inter class distance measurements are calculated. The presented pipeline performs an automated selection of the proper 3D reconstruction method for on the one hand wiry (power line, and on the other hand solid objects (surrounding. The automated selection is realized by performing pixel-wise semantic segmentation of the input images using a Fully Convolutional Neural Network. Due to the geo-referenced semantic 3D reconstructions a documentation of areas where maintenance work has to be performed is inherently included in the distance measurements and can be extracted easily. We evaluate the influence of the semantic segmentation according to the 3D reconstruction and show that the automated semantic separation in wiry and dense objects of the 3D reconstruction routine improves the quality of the vegetation undercut inspection. We show the generalization of the semantic segmentation to datasets acquired using different acquisition routines and to varied seasons in time.

  13. Characterizing corridor-level travel time distributions based on stochastic flows and segment capacities

    Directory of Open Access Journals (Sweden)

    Hao Lei

    2015-12-01

    Full Text Available Trip travel time reliability is an important measure of transportation system performance and a key factor affecting travelers’ choices. This paper explores a method for estimating travel time distributions for corridors that contain multiple bottlenecks. A set of analytical equations are used to calculate the number of queued vehicles ahead of a probe vehicle and further capture many important factors affecting travel times: the prevailing congestion level, queue discharge rates at the bottlenecks, and flow rates associated with merges and diverges. Based on multiple random scenarios and a vector of arrival times, the lane-by-lane delay at each bottleneck along the corridor is recursively estimated to produce a route-level travel time distribution. The model incorporates stochastic variations of bottleneck capacity and demand and explains the travel time correlations between sequential links. Its data needs are the entering and exiting flow rates and a sense of the lane-by-lane distribution of traffic at each bottleneck. A detailed vehicle trajectory data-set from the Next Generation SIMulation (NGSIM project has been used to verify that the estimated distributions are valid, and the sources of estimation error are examined.

  14. Safe Shores and Resilient Transit Corridors: Using Science, Design, and Stakeholder Partnerships to Address Connecticut's Coastal Vulnerabilities

    Science.gov (United States)

    French, R. A.; Felson, A. J.; Kirmmse, E.; Hagemann, K.

    2015-12-01

    Connecticut's densely developed coastline is highly vulnerable to sea level rise and coastal storms. 95% of the state's entire population lives within 50 miles of the shore. Connecticut has more than $542 billion in insured assets in harms way, only Florida has a greater exposure. As part of the state of Connecticut Phase 1 application for the HUD National Disaster Resilience Competition, the Connecticut Institute for Resilience and Climate Adaptation (CIRCA) at the University of Connecticut undertook an assessment of coastal vulnerabilities, including the impacts of sea level rise on the frequency of flooding, socioeconomic factors, critical infrastructure, and housing using data collected from federal, state, and municipal sources. Connecticut's unique geology, characterized by a glaciated coastline with highly erodible former deltas and elevated ridgelines extending out to rocky headlands, became the basis of the climate adaptation approach. Together with a nine state agency workgroup, municipal and regional government, and non-profit and industry representatives, CIRCA and the Yale UED lab developed a long-term urban redevelopment solution of resilient access and egress corridors layered over ridgelines and resilient zones of transit oriented economic development linked to shoreline communities. This concept can be applied in both Connecticut's coastal cities like New Haven and its smaller towns. The process demonstrated the effective partnership between the universities and state agencies in bringing the science of flood modeling and mapping together with innovative design to create solutions for climate adaptation. However, it also revealed significant gaps in data availability to analyze the economic and social drivers for adopting different adaptation strategies. Furthermore, the accuracy of current flood mapping tools needs to be improved to predict future flooding at the municipal project scale. As Connecticut and other states move forward with resilience

  15. Dynamique institutionnelle des transferts de gestion dans le corridor Fandriana-Vondrozo

    Directory of Open Access Journals (Sweden)

    Thierry Ganomanana

    2011-06-01

    Full Text Available Ten years after their creation, the operation of the community-based natural resource management policy named ‘transfert de gestion’ – the 1996 GELOSE law (applied to any kind of natural resources, and the 2001 GCF decree (only applied to forests – remains little understood. The forest corridor linking Ranomafana and Andringitra National Parks has been extended south, and since 2006 the Fandriana-Vondrozo Corridor has been established as a new protected area within the Madagascar Protected Area System. Eighty-two sites of transfert de gestion have been created since 2001 in the Fandriana-Vondrozo Corridor and Randriamahaleo III are managed by local community associations named COBA. Management is determined by law but is locally adapted to each site. We analyze the dynamic of the community forest management system using six variables and 19 modes: year of creation (five modes, legal form of management (two modes, locality (two modes, principal NGO partners (five modes, management objective (two modes, and surface area of the transferred site (three modes. There are four institutions in charge of forest management: local community associations (COBA, which manage the forest in their territory; the Forest Service (Eaux et Forêt representing the State, which controls this management; the commune, the smallest decentralized unit of the State, which manages the whole communal territory including forests; and NGOs, which facilitate the process. In order to investigate institutional tendencies, the sites of transfert de gestion are analyzed using Multiple Correspondence Analysis. The sites are distributed in the first two factorial plans with percentage variance of 18.5 % and 15.8 % according to their objectives: 1 pure conservation, and 2 economic development. Three types of NGO are distinguished by the form and duration of their support to COBA. The NGOs with greatest weight in the process are those which support the transfert de gestion

  16. Molecular Corridor Based Approach for Description of Evolution of Secondary Organic Aerosols

    Science.gov (United States)

    Li, Y., Sr.; Poeschl, U.; Shiraiwa, M.

    2015-12-01

    Organic aerosol is ubiquitous in the atmosphere and its major component is secondary organic aerosol (SOA). Formation and evolution of SOA is a complex process involving coupled chemical reactions and mass transport in the gas and particle phases (Shiraiwa et al., 2014). Current air quality models do not embody the full spectrum of reaction and transport processes, nor do they identify the dominant rate-limiting steps in SOA formation, resulting in the significant underprediction of observed SOA concentrations, which precludes reliable quantitative predictions of aerosols and their environmental impacts. Recently, it has been suggested that the SOA chemical evolution can be represented well by "molecular corridor" with a tight inverse correlation between molar mass and volatility of SOA oxidation products (Shiraiwa et al., 2014). Here we further analyzed the structure, molar mass and volatility of 31,000 unique organic compounds. These compounds include oxygenated organic compounds as well as nitrogen- and sulfur-containing organics such as amines, organonitrates, and organosulfates. Results show that most of those compounds fall into this two-dimensional (2-D) space, which is constrained by two boundary lines corresponding to the volatility of n -alkanes CnH2n+2 and sugar alcohols CnH2n+2On. A method to predict the volatility of nitrogen- and sulfur- containing compounds is developed based on those 31,000 organic compounds. It is shown that the volatility can be well predicted as a function of chemical composition numbers, providing a way to apply this 2-D space to organic compounds observed in real atmosphere. A comprehensive set of observation data from laboratory experiments, field campaigns and indoor measurements is mapped to the molecular corridor. This 2-D space can successfully grasp the properties of organic compounds formed in different atmospheric conditions. The molecular corridor represents a new framework in which chemical and physical properties as

  17. Secondary wind dispersal enhances long-distance dispersal of an invasive species in urban road corridors

    Directory of Open Access Journals (Sweden)

    Ingo Kowarik

    2011-08-01

    Full Text Available Roads contribute to habitat fragmentation and function as dispersal barriers for many organisms. At the same time many nonnative plant species are associated with road systems, a relationship that has been explained by the availability of disturbed habitats along roadsides and traffic-mediated dispersal of species. By studying secondary wind dispersal (SWD over paved ground in an urban road corridor, we add the perspective of corridor-specific, but traffic-independent dispersal processes to the complex dispersal systems along roads. We analyzed (1 the seed shadow of an invasive tree Ailanthus altissima along a sidewalk subsequent to a strong wind and (2 the movements of painted samaras of this species released at ground level at the same site to identify the functioning of SWD. For the first experiment, we searched for samaras in the vicinity of an isolated tree three days after a strong wind. For the second experiment, we tracked the movement of the released samaras repeatedly over a period of 9–11 days, approximated probability-distance functions to the frequency distribution of samaras along the transect for different times after release, and related nearby measured wind data to changes in dispersal kernels. Single samaras from an isolated tree formed a seed shadow that extended for a distance of 456m and fragments of fruit clusters traveled up to 130m. Forty-twopercent of the sampled samaras were moved >100 m. The second experiment revealed that painted samaras released on the ground were moved up to 150m over the pavement. Dispersal distances increased with time after seed release. A significant increase in the scale parameter b of the dispersal kernel with higher wind sums above 3.7 m/s illustrates a threshold for movement of samaras over the ground. Habitat shifts to safe sites for germination occurred during SWD, and different types of pavement influenced these processes. Smooth-surfaced pavement enhanced SWD, while cobbles with

  18. Vegetation composition and structure of woody plant communities along urban interstate corridors in Louisville, KY, U.S.A

    Science.gov (United States)

    Tara L. E. Trammell; Margaret M. Carreiro

    2011-01-01

    Urban forests adjacent to interstate corridors are understudied ecosystems across cities. Despite their small area, these forests may be strategically located to provide large ecosystem services due to their ability to act as a barrier against air pollutants and noise as well as to provide flood control. The woody vegetation composition and structure of forests...

  19. Arbuscular mycorrhizal fungi associations of vascular plants confined to river valleys: towards understanding the river corridor plant distribution.

    Science.gov (United States)

    Nobis, Agnieszka; Błaszkowski, Janusz; Zubek, Szymon

    2015-01-01

    The group of river corridor plants (RCP) includes vascular plant species which grow mainly or exclusively in the valleys of large rivers. Despite the long recognized fact that some plant species display a corridor-like distribution pattern in Central Europe, there is still no exhaustive explanation of the mechanisms generating this peculiar distribution. The main goal of this study was therefore to investigate whether arbuscular mycorrhizal fungi (AMF) and fungal root endophytes influence the RCP distribution. Arbuscular mycorrhizae (AM) were observed in 19 out of 33 studied RCP. Dark septate endophytes (DSE) and Olpidium spp. were recorded with low abundance in 15 and 10 plant species, respectively. The spores of AMF were found only in 32% of trap cultures established from the soils collected in the river corridor habitats. In total, six widespread AMF species were identified. Because the percentage of non-mycorrhizal species in the group of RCP is significant and the sites in river corridors are characterized by low AMF species diversity, RCP can be outcompeted outside river valleys by the widespread species that are able to benefit from AM associations in more stable plant-AMF communities in non-river habitats.

  20. Evaluating the effect of corridors and landscape heterogeneity on dispersal probability: a comparison of three spatially explicit modelling approaches

    DEFF Research Database (Denmark)

    Jepsen, J. U.; Baveco, J. M.; Topping, C. J.

    2004-01-01

    or populations in space given a specific configuration of habitat patches. We evaluated how the choice of model influenced predictions regarding the effect of patch- and corridor configuration on dispersal probabilities and the number of successful immigrants of a simulated small mammal. Model results were...... analysed both at the level of the entire habitat network and at the level of individual patches....

  1. Agricultural conservation planning framework: 2. Classification of riparian buffer design-types with application to assess and map stream corridors

    Science.gov (United States)

    A watershed’s riparian corridor presents opportunities to stabilize streambanks, intercept runoff, and influence shallow groundwater with riparian buffers. This paper presents a system to classify these riparian opportunities and apply it towards riparian management planning in HUC12 watersheds. Hig...

  2. Carbon pools in stream-riparian corridors: legacy of disturbance along mountain streams of south-eastern Wyoming

    Science.gov (United States)

    Claire M. Ruffing; Kathleen A. Dwire; Melinda D. Daniels

    2016-01-01

    Streams and their accompanying riparian environments are intrinsic components of terrestrial carbon cycling. However, they have been understudied in terms of the magnitude of their storage components and the role of disturbance in determining carbon storage capacity. This study presents partial carbon budgets for stream-riparian corridors along six study...

  3. Automatic construction of aerial corridor for navigation of unmanned aircraft systems in class G airspace using LiDAR

    Science.gov (United States)

    Feng, Dengchao; Yuan, Xiaohui

    2016-05-01

    According to the airspace classification by the Federal Aviation Agency, Class G airspace is the airspace at 1,200 feet or less to the ground, which is beneath class E airspace and between classes B-D cylinders around towered airstrips. However, the lack of flight supervision mechanism in this airspace, unmanned aerial system (UAS) missions pose many safety issues. Collision avoidance and route planning for UASs in class G airspace is critical for broad deployment of UASs in commercial and security applications. Yet, unlike road network, there is no stationary marker in airspace to identify corridors that are available and safe for UASs to navigate. In this paper, we present an automatic LiDAR-based airspace corridor construction method for navigation in class G airspace and a method for route planning to minimize collision and intrusion. Our idea is to combine LiDAR to automatically identify ground objects that pose navigation restrictions such as airports and high-rises. Digital terrain model (DTM) is derived from LiDAR point cloud to provide an altitude-based class G airspace description. Following the FAA Aeronautical Information Manual, the ground objects that define the restricted airspaces are used together with digital surface model derived from LiDAR data to construct the aerial corridor for navigation of UASs. Preliminary results demonstrate competitive performance and the construction of aerial corridor can be automated with much great efficiency.

  4. Causes of Sandstorm Disaster and Strategies against Desertification——A Case Study of Hexi Corridor in Northwest China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This case study outlines the problems faced by the peoples of the Hexi Corridor. These problems are serious and urgent, and are representative of those faced by other communities right across western China. The root causes are outlined and some remedies are suggested. The practical measures proposed under China's National Action Plan to Combat Desertification are described and discussed.

  5. 77 FR 49856 - Environmental Impact Statement for the Salinas to San Luis Obispo Portion of the Coast Corridor...

    Science.gov (United States)

    2012-08-17

    ... in the future as continued growth in population, employment, and tourism activity is expected to... infrastructure that is significantly undersized for the volumes it currently accommodates, much less future... fully booked during peak travel periods. Aging Rail Infrastructure--Investment in corridor rail...

  6. Effects of Width, Edge and Habitat on the Abundance and Nesting Success of Scrub-shrub Birds in Powerline Corridors

    Science.gov (United States)

    David I. King; Richard B. Chandler; Jeffrey M. Collins; Wayne R. Petersen; Thomas E. Lautzenheiser

    2009-01-01

    Concern about declines in scrub–shrub bird populations has resulted in efforts to create and maintain habitat for these species. Vegetation within powerline corridors is managed to prevent contact of vegetation with transmission lines, and comprises approximately 2% of all of habitat for scrub–shrub birds in southern New England. Although previous studies have...

  7. Examining the effect of speed, roadside features, and roadway geometry on crash experience along a rural corridor

    Institute of Scientific and Technical Information of China (English)

    Donald C.Watson Jr.; Ahmed Al-Kaisy; Nathan D.Anderson

    2014-01-01

    This paper presents a current investigation into crash experience along a 15.7-mile rural corridor in southwest Montana with the aim of better understanding crash causal factors along the corridor. The study utilized ten years of crash data, geometric data, and observed free-flow speed data along the corridor. A systematic approach was used where every tenth of a mile was described in term of the crash experience, speed, alignment, and roadside features. Using bivariate and multivariate statistical anal-yses, the study investigated the crash experience along the corridor as well as some of the underlying relationships which could explain some of the crash causal factors. Results show a strong association between crash rates and horizontal curvatures even for flat curves that can be negotiated at speeds above the posted speed limit, per the highway design equations. Higher crash rates were also found to be associated with the difference between the observed free-flow speeds and the speed dictated by the curve radius or sight distance as per the design equations. Further, results strongly support the safety benefits of guardrails as evidenced by the lower crash rates and severities. The presence of fixed objects and the steepness of side slopes were also found to have an effect on crash rates and severities.

  8. The rise and fall of a policy: policy succession and the attempted termination of ecological corridors policy in the Netherlands

    NARCIS (Netherlands)

    Turnhout, E.

    2009-01-01

    In policy analysis, studies on policy termination are rare. This article offers such a study. It presents the story of how, despite attempts by the government to terminate it, Dutch nature policy on ecological corridors continued to be implemented by regional governments and in the field. A case

  9. 75 FR 59323 - Early Scoping for the Alternatives Analysis of the North Corridor Transit Project in Metropolitan...

    Science.gov (United States)

    2010-09-27

    ... Project in Metropolitan Seattle AGENCY: Federal Transit Administration, DOT. ACTION: Early Scoping Notice... meetings and the range of alternatives currently identified to address the project's purpose are described....soundtransit.org/NorthHCT . ADDRESSES: Roger Iwata, North Corridor Project, Sound Transit, 401 S. Jackson...

  10. Mediating factors of land use change among coffee farmers in a biological corridor

    DEFF Research Database (Denmark)

    Bosselmann, Aske Skovmand

    2012-01-01

    Trees in agricultural landscapes are important for the provision of environmental services. This study assesses the loss of shade coffee during a 9 year period in a biological corridor in Costa Rica, and investigates the mediating factors of land use change. Following a conceptual framework...... that presents how household and farm characteristics mediate the interplay between underlying and proximate causes of land use change, the effect of the mediating factors is determined by applying an ordered probit model to household and land use data for 2000 and 2009 from 217 former and present coffee farmers....... Additional 224 telephone interviews supplement the data on land use change. Results show a 50% reduction in the coffee area and a corresponding loss of trees. Family labor, age of household head, coffee prices, and use of shade tree products significantly reduce the probability of converting the coffee field...

  11. Controlling inclination in rotary mode in tight TVD corridors using a 2-dimensional steerable system

    Energy Technology Data Exchange (ETDEWEB)

    Rasheed, W. [Andergauge Ltd., Dubai (United Arab Emirates)

    2000-11-01

    The use of a 2D rotary steerable system to control the inclination of true vertical depth (TVD) and horizontal wells was discussed. The system was introduced in 1986 and has since been used successfully in more than 4,500 sections and 500 horizontal wells worldwide. Directional corrections are unlikely with the use of this system. The system can often drill to total depth in a single bit run. As well bore inclination increases, bit walk becomes less significant. It was concluded that the 2D rotary steerable system is capable of drilling horizontal sections effectively and efficiently. It can meet tight TVD corridor objectives with an accuracy of {+-}2 feet. It also has other benefits regarding hole quality. 11 refs., 5 tabs.

  12. From Migration Corridors to Clusters: The Value of Google+ Data for Migration Studies

    CERN Document Server

    Messias, Johnnatan; Weber, Ingmar; Zagheni, Emilio

    2016-01-01

    Recently, there have been considerable efforts to use online data to investigate international migration. These efforts show that Web data are valuable for estimating migration rates and are relatively easy to obtain. However, existing studies have only investigated flows of people along migration corridors, i.e. between pairs of countries. In our work, we use data about "places lived" from millions of Google+ users in order to study migration "clusters", i.e. groups of countries in which individuals have lived. For the first time, we consider information about more than two countries people have lived in. We argue that these data are very valuable because this type of information is not available in traditional demographic sources which record country-to-country migration flows independent of each other. We show that migration clusters of country triads cannot be identified using information about bilateral flows alone. To demonstrate the additional insights that can be gained by using data about migration c...

  13. From the CERN web: The Art of Science, Theory corridor, DAMPE and more

    CERN Multimedia

    2016-01-01

    This section highlights articles, blog posts and press releases published in the CERN web environment over the past weeks. This way, you won’t miss a thing...     "Move over Mr Einstein!" A scientific experiment ignites creativity and dialogue 26 February – CMS Collaboration The inspiration for the latest art exhibition at the Cité du Temps came from a scientific experiment the height of a six-floor building, built to the precision of the thickness of a human hair. “CMS – The Art of Science”, by Michael Hoch, running from 27 February to 10 April 2016, delivers a dynamic dialogue between art and science. A combination of photography, collage and installations, it pays tribute to the thousands of people who constructed the Compact Muon Solenoid (CMS) Experiment at CERN’s Large Hadron Collider (LHC) near Geneva. Continue to read…   One of CERN’s Theory corridors &ndas...

  14. Virtual Team and Trust Relationship: Focus Group Interviews in Multimedia Super Corridor Status Companies

    Directory of Open Access Journals (Sweden)

    Norizah Aripin

    2011-12-01

    Full Text Available This paper aims to discuss the trust relationship in virtual teams in Multimedia Super Corridor (MSC status companies. The study used qualitative method that is phenomenology approach through focus group interviews. In-depth interview were also used with semi-structured and openended questions. The interviews involved six staffs at different position in virtual team (two team leaders, and four team members. The interviews were recorded, transcribed and analyzed according to the thematic analysis. Results showed that dimensions on virtual team trust relationship including interpersonal communication, personality, team members size, face-to-face meeting needs, safety information when discussing face-to-face in public places, and difficulty to recall interaction via video conferencing with other team members.

  15. Telemedicine and medical informatics in the multimedia super corridor: the Malaysian vision.

    Science.gov (United States)

    Abidi, S S; Goh, A; Yusoff, Z

    1998-01-01

    The practice of medicine, with its wide range of environmental conditions and complex dependencies, has long been used as a test bed for various advanced technologies. Telemedicine, as conceptualised within the Multimedia Super Corridor (MSC) context, is seen as the application of several relatively mature technologiesartificial intelligence (AI), multimedia communication and information systems (IS) amongst othersso as to benefit a large cross-section of the Malaysian population. We will discuss in general terms the Malaysian vision on the comprehensive MSC telemedicine solution, its functionality and associated operational conditions. In particular, this paper focuses on the conceptualisation of one key telemedical component i.e. the Lifetime Health Plan (LHP) system, which is eventually intended to be a distributed multi-module application for the periodic monitoring and generation of health-care advisories for upwards of 20 million Malaysians.

  16. A water balance model to estimate flow through the Old and Middle River corridor

    Science.gov (United States)

    Andrews, Stephen W.; Gross, Edward S.; Hutton, Paul H.

    2016-01-01

    We applied a water balance model to predict tidally averaged (subtidal) flows through the Old River and Middle River corridor in the Sacramento–San Joaquin Delta. We reviewed the dynamics that govern subtidal flows and water levels and adopted a simplified representation. In this water balance approach, we estimated ungaged flows as linear functions of known (or specified) flows. We assumed that subtidal storage within the control volume varies because of fortnightly variation in subtidal water level, Delta inflow, and barometric pressure. The water balance model effectively predicts subtidal flows and approaches the accuracy of a 1–D Delta hydrodynamic model. We explore the potential to improve the approach by representing more complex dynamics and identify possible future improvements.

  17. An Intelligent Robotic Hospital Bed for Safe Transportation of Critical Neurosurgery Patients Along Crowded Hospital Corridors.

    Science.gov (United States)

    Wang, Chao; Savkin, Andrey V; Clout, Ray; Nguyen, Hung T

    2015-09-01

    We present a novel design of an intelligent robotic hospital bed, named Flexbed, with autonomous navigation ability. The robotic bed is developed for fast and safe transportation of critical neurosurgery patients without changing beds. Flexbed is more efficient and safe during the transportation process comparing to the conventional hospital beds. Flexbed is able to avoid en-route obstacles with an efficient easy-to-implement collision avoidance strategy when an obstacle is nearby and to move towards its destination at maximum speed when there is no threat of collision. We present extensive simulation results of navigation of Flexbed in the crowded hospital corridor environments with moving obstacles. Moreover, results of experiments with Flexbed in the real world scenarios are also presented and discussed.

  18. The woody vegetation communities of the Hluhluwe-Corridor- Umfolozi Game Reserve Complex

    Directory of Open Access Journals (Sweden)

    A. Whateley

    1983-12-01

    Full Text Available Land units for the 900 km- Hluhluwe-Corridor-Umfolozi Game Reserve Complex in north eastern Natal were identified on aerial photographs. The physiognomy, dominants and description of the woody vegetation for each unit were identified during ground inspections and. where necessary, the point-centred quarter method was applied. Two forest, two riverine forest, ten woodland and two thicket communities were recognized. These communities are described according to their distribution, height and percentage frequency of the components in the different canopy strata. A map at a scale of 1:25 000 was also compiled. Some of these communities are compared with other similar woodlands previously described for Natal. In some communities the frequency of certain dominant canopy species in the under tree strata was extremely low and autecological research has been suggested.

  19. Hydrologic indicators of hot spots and hot moments of mercury methylation potential along river corridors

    Science.gov (United States)

    Singer, Michael B.; Harrison, Lee R.; Donovan, Patrick M.; Blum, Joel D.; Marvin-DiPasquale, Mark C.

    2016-01-01

    The biogeochemical cycling of metals and other contaminants in river-floodplain corridors is controlled by microbial activity responding to dynamic redox conditions. Riverine flooding thus has the potential to affect speciation of redox-sensitive metals such as mercury (Hg). Therefore, inundation history over a period of decades potentially holds information on past production of bioavailable Hg. We investigate this within a Northern California river system with a legacy of landscape-scale 19th century hydraulic gold mining. We combine hydraulic modeling, Hg measurements in sediment and biota, and first-order calculations of mercury transformation to assess the potential role of river floodplains in producing monomethylmercury (MMHg), a neurotoxin which accumulates in local and migratory food webs. We identify frequently inundated floodplain areas, as well as floodplain areas inundated for long periods. We quantify the probability of MMHg production potential (MPP) associated with hydrology in each sector of the river system as a function of the spatial patterns of overbank inundation and drainage, which affect long-term redox history of contaminated sediments. Our findings identify river floodplains as periodic, temporary, yet potentially important, loci of biogeochemical transformation in which contaminants may undergo change during limited periods of the hydrologic record. We suggest that inundation is an important driver of MPP in river corridors and that the entire flow history must be analyzed retrospectively in terms of inundation magnitude and frequency in order to accurately assess biogeochemical risks, rather than merely highlighting the largest floods or low-flow periods. MMHg bioaccumulation within the aquatic food web in this system may pose a major risk to humans and waterfowl that eat migratory salmonids, which are being encouraged to come up these rivers to spawn. There is a long-term pattern of MPP under the current flow regime that is likely to be

  20. Hydrologic indicators of hot spots and hot moments of mercury methylation potential along river corridors.

    Science.gov (United States)

    Singer, Michael Bliss; Harrison, Lee R; Donovan, Patrick M; Blum, Joel D; Marvin-DiPasquale, Mark

    2016-10-15

    The biogeochemical cycling of metals and other contaminants in river-floodplain corridors is controlled by microbial activity responding to dynamic redox conditions. Riverine flooding thus has the potential to affect speciation of redox-sensitive metals such as mercury (Hg). Therefore, inundation history over a period of decades potentially holds information on past production of bioavailable Hg. We investigate this within a Northern California river system with a legacy of landscape-scale 19th century hydraulic gold mining. We combine hydraulic modeling, Hg measurements in sediment and biota, and first-order calculations of mercury transformation to assess the potential role of river floodplains in producing monomethylmercury (MMHg), a neurotoxin which accumulates in local and migratory food webs. We identify frequently inundated floodplain areas, as well as floodplain areas inundated for long periods. We quantify the probability of MMHg production potential (MPP) associated with hydrology in each sector of the river system as a function of the spatial patterns of overbank inundation and drainage, which affect long-term redox history of contaminated sediments. Our findings identify river floodplains as periodic, temporary, yet potentially important, loci of biogeochemical transformation in which contaminants may undergo change during limited periods of the hydrologic record. We suggest that inundation is an important driver of MPP in river corridors and that the entire flow history must be analyzed retrospectively in terms of inundation magnitude and frequency in order to accurately assess biogeochemical risks, rather than merely highlighting the largest floods or low-flow periods. MMHg bioaccumulation within the aquatic food web in this system may pose a major risk to humans and waterfowl that eat migratory salmonids, which are being encouraged to come up these rivers to spawn. There is a long-term pattern of MPP under the current flow regime that is likely to be

  1. Consequences of Environmental Service Payments for Forest Retention and Recruitment in a Costa Rican Biological Corridor

    Directory of Open Access Journals (Sweden)

    Steven J. Hollenhorst

    2009-06-01

    Full Text Available Compensation to landowners for forest-derived environmental services has gained international recognition as a mechanism to combat forest loss and fragmentation. This approach is widely promoted, although there is little evidence demonstrating that environmental service payments encourage forest stewardship and conservation. Costa Rica provides a unique case study in which a 1996 Forestry Law initiated environmental service payments and prohibited forest conversion to other land uses. We examined these novel policies to determine their influence on landowner decisions that affect forest change, carbon services, and connectivity in a 2425 km² biological corridor. We used Landsat images to compare land-cover changes before and after 1996, and linked these data to landowner surveys investigating land-use decisions. Carbon stocks and storage in secondary forests were also examined. Forest change observations were corroborated by landowner survey data, indicating that the 1996 Forestry Law and environmental service payments contributed positively to forest retention and recruitment. Socioeconomic conditions also favored forest protection. Rates of natural forest loss declined from -1.43% to -0.10%/yr after 1996. Forest cover and connectivity were maintained through tree plantations and secondary forest recruitment, although forest heterogeneity increased as these forest types sometimes replaced natural forest. Carbon storage in secondary forest approached levels in primary forest after 25–30 yr of succession, although few landowners retained natural regeneration. Secondary forests will persist as minor landscape components without legal or financial incentives. The Costa Rican experience provides evidence that environmental service payments can be effective in retaining natural forest and recruiting tree cover within biological corridors.

  2. Aggregate supply and demand modeling using GIS methods for the front range urban corridor, Colorado

    Science.gov (United States)

    Karakas, Ahmet; Turner, Keith

    2004-07-01

    The combined use of allocation modeling and geographical information system (GIS) technologies for providing quantitative assessments of aggregate supply and demand is evaluated using representative data for the Front Range Urban Corridor (FRUC) in Colorado. The FRUC extends from the Colorado-Wyoming border to south of Colorado Springs, and includes Denver and the major urban growth regions of Colorado. In this area, aggregate demand is high and is increasing in response to population growth. Neighborhood opposition to the establishment of new pits and quarries and the depletion of many deposits are limiting aggregate supplies. Many sources are already covered by urban development or eliminated from production by zoning. Transport of aggregate by rail from distant resources may be required in the future. Two allocation-modeling procedures are tested in this study. Network analysis procedures provided within the ARC/INFO software, are unsatisfactory. Further aggregate allocation modeling used a model specifically designed for this task; a modified version of an existing Colorado School of Mines allocation model allows for more realistic market analyses. This study evaluated four scenarios. The entire region was evaluated with a scenario reflecting the current market and by a second scenario in which some existing suppliers were closed down and new potential suppliers were activated. The conditions within the Denver metropolitan area were studied before and after the introduction of three possible rail-to-truck aggregate distribution centers. GIS techniques are helpful in developing the required database to describe the Front Range Urban Corridor aggregate market conditions. GIS methods allow the digital representation of the regional road network, and the development of a distance matrix relating all suppliers and purchasers.

  3. Value and Resilience in the Case of 'Invasive' Tamarix in the Colorado River Riparian Corridor

    Science.gov (United States)

    Loring, P. A.; Gerlach, S.; Zamora, F.

    2009-12-01

    A common premise of science for conservation and sustainability is an assumption that despite any human definitions of value, there are ecological first principles, e.g., resilience, which must be understood if sustainability is to be possible. As I show here, however, pursuits such as restoration, conservation, and sustainability remain tangled in (and sometimes at odds with one another regarding) many value-laden decisions regarding the equity, justice, and morality of human-environment interactions. These include such important decisions as: what should be restored or sustained and for whom, how and by whom, and at what cost. This paper uses examples from the lower Colorado River Riparian Corridor, in particular the issue of the so-called ‘invasive’ saltcedar (Tamarix spp.), to illustrate some of the implicit value judgments common to the practice of managing ecosystems. There are many possible perspectives to be taken on a matter like Tamarix, each implicitly or explicitly representing different worldviews and agendas for the ecosystems in question. Resilience theory provides one such perspective, but as I show here, it proves incapable of producing recommendations for managing the corridor that are free of subjective valuations. I end with a case study of habitat and Tamarix management practices in the Mexican portion of the Colorado River Delta, highlighting the proven potential when up-front values are explicitly coupled to the practice of sustainability science, rather than left as details for 'good governance,' a realm presently imagined as separate from science, to sort out. Map of the Colorado River Delta. The Sonoran Institute manages projects in the Mexican portion of the Colorado River Delta region, along the Rio Hardy, the mainstem of the Colorado River in Baja California, MX and in the Cienega de Santa Clara wetlands, Sonora, MX. Map courtesy of Water Education Foundation. www.watereducation.org

  4. Hydrologic indicators of hot spots and hot moments of mercury methylation along river corridors

    Science.gov (United States)

    Singer, Michael; Harrison, Lee; Donovan, Patrick; Blum, Joel; Marvin-DiPasquale, Mark

    2016-04-01

    The biogeochemical cycling of metals and other contaminants river-floodplain corridors is controlled by microbial activity is often affected by dynamic redox conditions. Riverine flooding thus has the potential to affect speciation of redox-sensitive metals such as mercury (Hg). Therefore, flow history over a period of decades potentially holds information on past production of bioavailable Hg. We investigate this process within a Northern California river system that has a legacy of industrial-scale 19th century hydraulic gold mining. In the first known application of this methodology, we combine hydraulic modeling, measurements of Hg species in sediment and biota, and first-order calculations to assess the role of river floodplains in producing monomethylmercury (MMHg), which accumulates in local and migratory biota. We identify areas that represent 'hot spots' (frequently inundated areas of floodplains) and 'hot moments' (floodplain areas inundated for consecutive long periods). We show that the probability of MMHg production in each sector of the river system is dependent on the spatial patterns of overbank flow and drainage, which affect its long-term redox history. MMHg bioaccumulation within the aquatic food web may pose a major risk to humans and waterfowl that eat migratory salmonids, which are being encouraged to come up these rivers to spawn, and there appears to be no end to MMHg production under a regime of increasingly common large floods with extended duration. These findings identify river floodplains as periodic, temporary, yet important, loci of biogeochemical transformation in which contaminants may undergo change during limited periods of the historical hydrologic record. We suggest that inundation is the primary driver of MMHg production in river corridors and that the entire flow history must be analyzed in terms of magnitude and frequency of inundation in order to accurately assess biogeochemical risks, rather than merely highlighting the

  5. Spatial and temporal distribution of precipitation based on corrected TRMM data around the Hexi Corridor, China

    Institute of Scientific and Technical Information of China (English)

    Tao Zhang; YuanQing He; Jian Ma; Juan Pang

    2014-01-01

    Accurate rainfall distribution is difficult to acquire based on limited meteorological stations, especially in remote areas like high mountains and deserts. The Hexi Corridor and its adjacent regions (including the Qilian Mountains and the Alxa Plateau) are typical districts where there are only 30 available rain gauges. Tropical Rainfall Measuring Mission (TRMM) data provide a possible solution. After precision analysis of monthly 0.25 degree resolution TRMM 3B43 data from 1998 to 2012, we find that the correlations between TRMM 3B43 estimates and rain gauge precipitation are significant overall and in each station around the Hexi Corridor;however, the biases of annual precipitation differ in different stations and are seriously overestimated in most of the sites. Thus, Inverse Distance Weighting (IDW) interpolation method was used to rectify TRMM data based on the difference between TRMM 3B43 estimates and rain gauge observations. The results show that rectified TRMM data present more details than rain gauges in remote areas where there are few stations, alt-hough they show high coherence of distribution. Precipitation decreases from southeast to northwest on an annual and seasonal scale. There are three rainfall centers (>500 mm) including Menyuan, Qilian and Toson Lake, and two low rain-fall centers (5 mm/a), Badain Jaran Desert (>2 mm/a), Toson Lake (>20 mm/a) and Qingtu Lake (>20 mm/a) which shows a significant increasing trend, while precipitation in Hala Lake (<-2 mm/a) and Tengger Desert (<-3 mm/a) demonstrates a decreasing trend.

  6. GIS (Geographic Information Systems) based automatic tool for selection of gas pipeline corridors

    Energy Technology Data Exchange (ETDEWEB)

    Matos, Denise F.; Menezes, Paulo Cesar P.; Paz, Luciana R.L.; Garcia, Katia C.; Cruz, Cristiane B.; Pires, Silvia H.M.; Damazio, Jorge M.; Medeiros, Alexandre M.

    2009-07-01

    This paper describes a methodology developed to build total accumulated surfaces in order to better select gas pipelines corridor alternatives. The methodology is based on the minimization of negative impacts and the use of Geographic Information Systems (GIS), allowing an automatic method of construction, evaluation and selection of alternatives, that will contribute to the decision making process. It is important to emphasize that this paper follows the assumptions presented on the research reports of a project sponsored by the Ministry of Mines and Energy (MME) and elaborated at the Electric Power Research Center (CEPEL), called 'Development of a Geographic Information System to Oil and Gas Sectors in Brazil', and also the studies d GTW Project (Gas to Wire). Gas pipelines, as for their linear characteristic, may cross a variety of habitats and settlements, increasing the complexity of their environmental management. Considering this reality, this paper presents a methodology that takes into account different environmental criteria (layers), according to the area impacted. From the synthesis of the criteria it is presented the total accumulated surface. It is showed an example of a hypothetical gas pipeline connection between two points using the total accumulated surface. To select the 'impact scores' of the features, the gas pipeline was considered as a linear feature, but the result is a region, formed by pixels, each pixel with an accumulated impact score lower than some arbitrary measure. This region is called 'corridor', and it is the final result obtained using the proposed methodology. (author)

  7. 基于红外图像和普通图像对比的高速公路可视度分析%Visibility Analysis for Freeway Based on Comparison of Ordinary and Infrared Images

    Institute of Scientific and Technical Information of China (English)

    杜豫川; 张晓明; 刘成龙; 刘翔

    2016-01-01

    The real-time monitoring of the low visibility of the freeway is very important for the traffic safety. This paper is aimed at establishing a visual distance monitoring model which is specially applied to freeway. The visual degree is proposed, and the ratio of the pixel points of the common image and infrared image is presented, which can reflect the actual visual distance, then the paper establishes the visibility model. At the same time, the temperature correction factor is proposed for reducing the impact of temperature on the infrared image, and the correction coefficient of the camera is proposed according to the different imaging quality. Then, several areas are got by dividing the infrared image according range, and according to the distance from the camera, the visual inspection table is established through cumulative percentage of pixels for different areas. Results show that the model has a certain degree of reliability and good accuracy of less than 11%, the visibility model can be used to well determine the visual distance in the low visibility environment, which can effectively improve freeway driving safety.%高速公路可视距离的实时检测对于低能见度预警保证行车安全具有重要意义,本文旨在建立一种专门应用于高速公路的可视距离检测模型。由此提出可视度概念,并创新性地通过普通图像和红外图像的像素点的比值来反映实际可视距离,进一步建立可视度推算模型。同时为减小温度对红外图像影响,提出并推导了温度修正系数;为减小仪器成像质量差异引入了相机修正系数,有效提高了模型的计算精度。根据离摄像机位置不同距离范围内像素点的累计百分比,建立可视度查阅表。现场试验结果表明:本文提出的可视度分析模型预测结果相对误差小于11%,该可视度模型能够在低能见度环境下准确判断可视距离,可以有效提高高速公路驾驶安全。

  8. 高速公路交通事故严重程度与交通流特征的关系研究%Relationships between Crash Severity and Traffic Flow Characteristics on Freeways

    Institute of Scientific and Technical Information of China (English)

    侯树展; 孙小端; 贺玉龙; 田启华

    2011-01-01

    In order to determine the relationships between traffic flow characteristics in the crash hour and crash severity, traffic flow and crash data were obtained from the JT Freeway for seven months. Detailed information about traffic flow characteristics was matched for each crash to build a data set of crashes and traffic flow in the crash hour. The distributing rules of traffic flow and crashes show that the number of crashes and crash severity peaks in some sections of volume, speed or proportion of trucks. On the basis of above analysis, using principal component analysis, a principal component index of traffic flow was presented to stand for the traffic flow characteristics by dimensionality reduction. Statistical analysis models for the relationship between crash severity and traffic flow principal component index were developed for freeway. The study shows crashes are more serious when the value of traffic flow principal component index is close to zero.%为研究交通事故发生前后交通流特征对事故严重程度的影响,以JT高速公路作为研究对象,长期观测和采集交通流及事故数据.将交通事故发生时段的交通流主要衡量指标与事故信息进行数据匹配,形成交通事故与事故小时交通流匹配数据集,并分析流量、速度、大车比例等交通流表征指标与不同等级事故数的分布规律.通过分析发现:在某些流量、速度或大车比例区段,交通事故数及其严重程度处于较高的水平.在此基础上,利用主成分分析(PCA)技术对衡量交通流特征的初始指标进行降维处理,用交通流主成分指标综合反映交通流特征,并建立事故严重程度与交通流主成分指标的统计分析模型.结果表明:交通流主成分指标趋于零的区段的事故严重程度明显高于其他区段.

  9. 高速公路路段交通量分析及轴载换算%Analysis of Traffic Volume and Equivalent Axle Load Factors in Freeway Sections

    Institute of Scientific and Technical Information of China (English)

    朱靓雯; 刘黎萍

    2016-01-01

    交通荷载数据对沥青路面设计和管理有重要作用。轴载谱方法可以更为全面、准确地描述交通荷载。文中收集了江西省部分高速公路荷载站点的实测轴载数据和交通量数据。通过对每一辆车进出收费站的名称识别,结合公路网分布统计得到各路段的交通荷载数据集合。对各路段实测轴载数据特征、交通增长率和累计标准轴次等进行分析,建立了轴载谱数据和交通量数据之间的关系,并给出了调查地区的当量轴次换算系数参考值。%Traffic loading data is very important for asphalt pavement design and management.Axle load spectrum is more comprehensive and accurate in describing the traffic load.This study collected the measured axle load data and traffic volume data of asphalt pavement freeways from toll gates in Jiangxi Province.Traffic loading data in freeway sections is obtained through the data from the en-trance and exit toll gate,combined with the highway network.The data was used to analyze the axle load spectrum factors,the number of accumulated equivalent axle loads,and the growth rate of equiv-alent axle loads.It has been found that the growth rate of equivalent axle loads in some highway sec-tions is negative.In addition,the relationship between axle load data and traffic volume data was de-veloped through the equivalent axle load factors,the value of which in investigated area was listed at last.

  10. 澳门大学新校区全天候立体步行连廊设计%The Design of the All-weather Stereoscopic Corridor of the New Campus for University of Macau

    Institute of Scientific and Technical Information of China (English)

    黄骏; 林燕

    2014-01-01

    澳门大学新校区的全天候步行连廊系统是校园环境的重要组成部分,又是校园各部分之间的联系手段,通过建立立体化多层次的步行系统,实现了人车分流与全校区全天候无障碍步行环境。通过对其建筑设计理念及手法的分析,阐释了立体化多层次步行校园的设计理念。%The all-weather stereoscopic corridor of the new campus for University of Macau,which links the whole campus,is an integral part of the campus environment. By setting up the stereoscopic multi-level walking system, it realizes the separation of people and vehicles and all-weather barrier-free walking environment in the campus. This paper will analyze the design of the stereoscopic corridor to discuss the design idea of the stereoscopic multi-level walking campus.

  11. Natural-color and color-infrared image mosaics of the Colorado River corridor in Arizona derived from the May 2009 airborne image collection

    Science.gov (United States)

    Davis, Philip A.

    2013-01-01

    The Grand Canyon Monitoring and Research Center (GCMRC) of the U.S. Geological Survey (USGS) periodically collects airborne image data for the Colorado River corridor within Arizona (fig. 1) to allow scientists to study the impacts of Glen Canyon Dam water release on the corridor’s natural and cultural resources. These data are collected from just above Glen Canyon Dam (in Lake Powell) down to the entrance of Lake Mead, for a total distance of 450 kilometers (km) and within a 500-meter (m) swath centered on the river’s mainstem and its seven main tributaries (fig. 1). The most recent airborne data collection in 2009 acquired image data in four wavelength bands (blue, green, red, and near infrared) at a spatial resolution of 20 centimeters (cm). The image collection used the latest model of the Leica ADS40 airborne digital sensor (the SH52), which uses a single optic for all four bands and collects and stores band radiance in 12-bits. Davis (2012) reported on the performance of the SH52 sensor and on the processing steps required to produce the nearly flawless four-band image mosaic (sectioned into map tiles) for the river corridor. The final image mosaic has a total of only 3 km of surface defects in addition to some areas of cloud shadow because of persistent inclement weather during data collection. The 2009 four-band image mosaic is perhaps the best image dataset that exists for the entire Arizona part of the Colorado River. Some analyses of these image mosaics do not require the full 12-bit dynamic range or all four bands of the calibrated image database, in which atmospheric scattering (or haze) had not been removed from the four bands. To provide scientists and the general public with image products that are more useful for visual interpretation, the 12-bit image data were converted to 8-bit natural-color and color-infrared images, which also removed atmospheric scattering within each wavelength-band image. The conversion required an evaluation of the

  12. Canonical Correlation Factors Causing the Formation of Accumulated Sand-belts along the Oasis Fringe in Hexi Corridor

    Institute of Scientific and Technical Information of China (English)

    Chang; Zhaofeng; Wang; Qiangqiang; Zhang; Jianhui; Tang; Jinnian; Zhu; Shujuan; Fan; Baoli; Zhang; Dabiao; Liu; Shizeng; Zhang; Guozhong; Li; Aide

    2014-01-01

    Accumulated sand-belts refer to those formed along the oasis fringe,especially at the upwind location,due to the accumulation of sand blocked by farmland windbreak. In the 60 years since the foundation of new China,a lot of trees have been planted for desertification combating in northwest and north China,thus,accumulated sand-belts were formed at the upwind location. The formation and the ecological effects of the accumulated sand-belts along the oasis fringe is a new scientific concern. To study the formation causes of these belts in Hexi corridor,21 samples were selected,and the height / width of the belts,as well as the vegetation,soil,soil moisture and climatic factors were investigated. This paper analyzed the correlation between the height / width of the belts and the vegetation,soil,soil moisture and climatic factors using the methods of variance analysis,correlation analysis and canonical correlation analysis. The results indicate that: the accumulated sand-belts take a trend of being high and wide in the east whereas low and narrow in the west,and most of the parts tend to be stable; the species on the belts are dominated by Tamarix austromongolica,the vegetation cover and the pure vegetation cover of different dominant species on the leeward slope of the accumulated sand-belts vary significantly. The canonical correlation analysis shows that: the height and width of accumulated sand-belt is the interaction of precipitation,distance to the sand source,leeward vegetation cover and annual average wind speed. Moreover,the height of accumulated sand-belts are negatively correlated to the soil moisture at the depth of 30- 50 cm,air humidity and leeward vegetation cover,and the width of the belts is also negatively correlated with the distance to the sand source. The ecological effects of the accumulated sand-belts are both positive( stopping sands from moving into farmland,protective role as an obstacle)and negative( when the belts decay and activate one day

  13. Susceptibilidad al deslizamiento en el corredor Siquirres-Turrialba Landslide susceptibility in the Siquirres-Turrialba corridor

    Directory of Open Access Journals (Sweden)

    Gustavo Segura

    2011-12-01

    Full Text Available Se presenta una zonificación de la susceptibilidad al deslizamiento en el sector entre las localidades de Siquirres y Turrialba, específicamente para un corredor de 10 km de ancho sobre la ruta del poliducto de RECOPE, que cubre una extensión aproximada de 330 km². El estudio se realizó a partir de la interpretación de fotografías aéreas, información bibliográfica y la aplicación del método Mora & Vahrson (Mora et al., 1992, sustituyendo el relieve relativo por un mapa de pendientes e incorporando un mapa inventario de deslizamientos en la evaluación del parámetro de susceptibilidad litológica. Como resultado de la zonificación, se obtuvo que las áreas correspondientes a susceptibilidad baja abarcan la mayor parte del mapa (33,9% y se presentan mayormente en sectores donde afloran las unidades litoestratigráficas Tuis, al sureste del área, Suretka y en algunos sectores de la formación Andesitas Poás. Las áreas correspondientes a susceptibilidad media (25,3% se presentan principalmente en rocas de las formaciones Andesitas Poás, Uscari y Guayacán; mientras que las áreas correspondientes a susceptibilidad alta (13,4% se presentan principalmente en sectores donde afloran las rocas de las formaciones Andesitas Poás, Uscari, Brechas La Unión y Río Banano.A landslide suceptibility zonation was performed in a 10 km wide corridor along the RECOPE pipeline between the cites of Siquirres and Turrialba. The total study area is 330 km². Analysis was based on aerial photointerpretation, bibliographic research and the application of the Mora-Vahrson method (Mora et al., 1992, in which slope was used instead of the internal relief parameter. A landslide inventory map was included in the evaluation of the lithological suceptibility parameter. Zonation resulted in a predominance of areas with low landslide susceptibility (33,9%, mostly located where Tuis Formation is present, south east of the study area, followed by Suretka

  14. SEMANTIC LABELLING OF ULTRA DENSE MLS POINT CLOUDS IN URBAN ROAD CORRIDORS BASED ON FUSING CRF WITH SHAPE PRIORS

    Directory of Open Access Journals (Sweden)

    W. Yao

    2017-09-01

    Full Text Available In this paper, a labelling method for the semantic analysis of ultra-high point density MLS data (up to 4000 points/m2 in urban road corridors is developed based on combining a conditional random field (CRF for the context-based classification of 3D point clouds with shape priors. The CRF uses a Random Forest (RF for generating the unary potentials of nodes and a variant of the contrastsensitive Potts model for the pair-wise potentials of node edges. The foundations of the classification are various geometric features derived by means of co-variance matrices and local accumulation map of spatial coordinates based on local neighbourhoods. Meanwhile, in order to cope with the ultra-high point density, a plane-based region growing method combined with a rule-based classifier is applied to first fix semantic labels for man-made objects. Once such kind of points that usually account for majority of entire data amount are pre-labeled; the CRF classifier can be solved by optimizing the discriminative probability for nodes within a subgraph structure excluded from pre-labeled nodes. The process can be viewed as an evidence fusion step inferring a degree of belief for point labelling from different sources. The MLS data used for this study were acquired by vehicle-borne Z+F phase-based laser scanner measurement, which permits the generation of a point cloud with an ultra-high sampling rate and accuracy. The test sites are parts of Munich City which is assumed to consist of seven object classes including impervious surfaces, tree, building roof/facade, low vegetation, vehicle and pole. The competitive classification performance can be explained by the diverse factors: e.g. the above ground height highlights the vertical dimension of houses, trees even cars, but also attributed to decision-level fusion of graph-based contextual classification approach with shape priors. The use of context-based classification methods mainly contributed to smoothing of

  15. Semantic Labelling of Ultra Dense Mls Point Clouds in Urban Road Corridors Based on Fusing Crf with Shape Priors

    Science.gov (United States)

    Yao, W.; Polewski, P.; Krzystek, P.

    2017-09-01

    In this paper, a labelling method for the semantic analysis of ultra-high point density MLS data (up to 4000 points/m2) in urban road corridors is developed based on combining a conditional random field (CRF) for the context-based classification of 3D point clouds with shape priors. The CRF uses a Random Forest (RF) for generating the unary potentials of nodes and a variant of the contrastsensitive Potts model for the pair-wise potentials of node edges. The foundations of the classification are various geometric features derived by means of co-variance matrices and local accumulation map of spatial coordinates based on local neighbourhoods. Meanwhile, in order to cope with the ultra-high point density, a plane-based region growing method combined with a rule-based classifier is applied to first fix semantic labels for man-made objects. Once such kind of points that usually account for majority of entire data amount are pre-labeled; the CRF classifier can be solved by optimizing the discriminative probability for nodes within a subgraph structure excluded from pre-labeled nodes. The process can be viewed as an evidence fusion step inferring a degree of belief for point labelling from different sources. The MLS data used for this study were acquired by vehicle-borne Z+F phase-based laser scanner measurement, which permits the generation of a point cloud with an ultra-high sampling rate and accuracy. The test sites are parts of Munich City which is assumed to consist of seven object classes including impervious surfaces, tree, building roof/facade, low vegetation, vehicle and pole. The competitive classification performance can be explained by the diverse factors: e.g. the above ground height highlights the vertical dimension of houses, trees even cars, but also attributed to decision-level fusion of graph-based contextual classification approach with shape priors. The use of context-based classification methods mainly contributed to smoothing of labelling by removing

  16. Corridor effect of the spatial changes of landscape patterns in arid areas: A case study of the river corridor areas in the middle and lower reaches of Tarim River

    Institute of Scientific and Technical Information of China (English)

    ZHOU Huarong; XIAO Duning; ZHOU Kefa

    2006-01-01

    The river corridor areas in the middle and lower reaches of the Tarim River are dominated by the traditional green corridors along the river section from the Qara Reservoir in Yuli County to the Taitema Lake in Ruoqiang County, which plays an important role in the social and economic development in the Tarim River Watershed with a extremely significant ecological functions. The buffer zones perpendicular to the watercourse were defined along both riversides at a 5-km interval beginning from the watercourse (10 km wider) using the method of the buffer zone analysis. The landscape pattern indexes of each buffer zone were calculated, and the indexes of the main landscape patterns were analyzed so as to reveal the radiative effect and the characteristics of the river corridors on landscape and patch levels.The results show that the radiative width is generally 30 km in the study area, and can be up to 50-70 km in sub- region FG1 because the study area is located in two drainage basins, with an ecological interstitial zone between them. The landscapes of woodlands and wetlands are generally distributed within the 10km buffer zone (it means that the buffer zone is 5 km away from the watercourse; the same hereafter)along both riversides. Moreover, the closer the buffer zone is to the watercourse, the higher the patch density and the largest patch index are. In the ecological and environmental regeneration for the study area,the extent of ecological effect of the river corridors 82must be fully considered, and the projects must be scientifically and rationally planned and designed.

  17. 沿海高速公路软土地基变形规律及处理效果%Deforming law of soft soil foundation of costal freeway and its processing result

    Institute of Scientific and Technical Information of China (English)

    李昭晖; 李昭俊

    2009-01-01

    以河北沿海高速公路软土地基试验工程的测试结果为基础,分析了塑料排水板及水泥搅拌桩超载预压两种处理方法下从路堤填筑到超载卸载以及路面结构层施工阶段软土地基的变形规律,并分析了地基处理的效果,从而为同类工程的设计和施工控制积累经验.%Based upon the experimental result of the soft soil foundation experiment of the costal freeway in Hebei, it analyses the deforming law of soft soil foundation in the periods of road embankment, unloading the overload and the construction of road surface structural layer under the processing methods of plastic drainage board and cement mixing pile overload pre-pressing, and analyses the result of road foundation pro-cessing, so as to accumulate experience for the design and construction control of similar projects.

  18. Deflection corridors of abdomen and thorax in oblique side impacts using equal stress equal velocity approach: comparison with other normalization methods.

    Science.gov (United States)

    Yoganandan, Narayan; Arun, Mike W J; Humm, John; Pintar, Frank A

    2014-10-01

    The first objective of the study was to determine the thorax and abdomen deflection time corridors using the equal stress equal velocity approach from oblique side impact sled tests with postmortem human surrogates fitted with chestbands. The second purpose of the study was to generate deflection time corridors using impulse momentum methods and determine which of these methods best suits the data. An anthropometry-specific load wall was used. Individual surrogate responses were normalized to standard midsize male anthropometry. Corridors from the equal stress equal velocity approach were very similar to those from impulse momentum methods, thus either method can be used for this data. Present mean and plus/minus one standard deviation abdomen and thorax deflection time corridors can be used to evaluate dummies and validate complex human body finite element models.

  19. [Identification of ecological corridors for Tibetan antelope and assessment of their human disturbances in the alpine desert of Qinghai-Tibet Plateau].

    Science.gov (United States)

    Zhuge, Hai-jin; Lin, Dan-qi; Li, Xiao-wen

    2015-08-01

    The alpine desert of Qinghai-Tibet Plateau (QTP) provides the largest habitats for those endangered ungulates (e.g., Tibetan antelope, Tibetan Kiang and wild yak) on the earth. However, human disturbance especially infrastructure constructions (e.g., railway & highway) has increasingly fragmented the habitats of those endangered ungulates by disturbing and interrupting their ecological corridors for their seasonal migration. Aiming at identifying the potential ecological corridors for Tibetan antelope, a GIS-based model-Linkage Mapper was used to model and detect the potential ecological corridors of Tibetan antelope based on the principle of least cost path. Three categories of ecological corridors, i. e., closed (inside reserves), linking (linking the reserves) and open (starting from reserve but ending outside) corridors were distinguished by their spatial interactions with existing major national nature reserves (i.e., Altun, Kekexili and Qiangtang NNRs) in the alpine desert of QTP, and their spatial patterns, conservation status associated with human disturbance were also examined. Although our research indicated a general ecological integration of both habitats and ecological corridors in the alpine desert ecosystem, increasing human disturbance should not be ignored, which particularly partially undermined the functioning of those ecological corridors linking the nature reserves. Considering disadvantages of prevailing separate administrative structure of nature reserve on the effective conservation of ecological corridors for those endangered ungulates, a coordinative conservation network among these major national nature reserves should be established to ensure the unified trans-boundary conservation efforts and to enhance its overall conservation efficacy by sharing information, knowledge and optimizing conservation resources.

  20. Tick communities at the expanding wildlife / cattle interface in the Eastern Cape Province, South Africa : implications for Corridor disease

    Directory of Open Access Journals (Sweden)

    E.R. Smith

    2010-05-01

    Full Text Available Corridor disease, transmitted by the brown ear tick (Rhipicephalus appendiculatus, is one of Africa's most pathogenic tick-borne diseases for cattle. With a focus on this species, we investigated the community parameters (richness, diversity and abundance of ticks in the Eastern Cape, South Africa, and how this may be linked to the increasing wildlife / cattle interface in the region. There were significantly more ticks of a greater diversity and richness at sites positioned at the wildlife / cattle interface ('treatment sites' compared to sites where wildlife was absent (controls. Significantly, R. appendiculatus was only found at the treatment sites. Therefore, it is believed that the wildlife / cattle interface may be playing a crucial role in increasing the occurrence, abundance and distribution of R. appendiculatus in the Eastern Cape. The implications of a Corridor disease outbreak in the region are discussed.

  1. ENVIRONMENTAL ASSESSMENT FOR THE PROPOSED WITHDRAWAL OF PUBLIC LANDS WITHIN AND SURROUNDING THE CALIENTE RAIL CORRIDOR, NEVADA

    Energy Technology Data Exchange (ETDEWEB)

    DOE

    2005-12-01

    The purpose for agency action is to preclude surface entry and the location of new mining claims, subject to valid existing rights, within and surrounding the Caliente rail corridor as described in the Yucca Mountain FEIS (DOE 2002). This protective measure is needed to enhance the safe, efficient, and uninterrupted evaluation of land areas for potential rail alignments within the Caliente rail corridor. The evaluation will assist the DOE in determining, through the Rail Alignment environmental impact statement (EIS) process, whether to construct a branch rail line, and to provide support to the BLM in deciding whether or not to reserve a ROW for the rail line under the Federal Land Policy and Management Act (FLPMA). The BLM participated as a cooperating agency in preparing this EA because it is the responsible land manager and BLM staff could contribute resource specific expertise.

  2. Evolution of the landscape along the Clear Creek Corridor, Colorado; urbanization, aggregate mining and reclamation

    Science.gov (United States)

    Arbogast, Belinda; Knepper, Daniel H.; Melick, Roger A.; Hickman, John

    2002-01-01

    Prime agricultural land along the Clear Creek floodplain, Colorado, attracted settlement in the 1850's but the demand for sand and gravel for 1900's construction initiated a sequence of events that exceeded previous interests and created the modified landscape and urban ecosystem that exists today. The Clear Creek valley corridor offers a landscape filled with a persistent visible and hidden reminder of it's past use. The map sheets illustrate the Clear Creek landscape as a series of compositions, both at the macro view (in the spatial context of urban structure and highways from aerial photographs) and micro view (from the civic scale where landscape features like trees, buildings, and sidewalks are included). The large-scale topographic features, such as mountains and terraces, appear 'changeless' (they do change over geologic time), while Clear Creek has changed from a wide braided stream to a narrow confined stream. Transportation networks (streets and highways) and spiraling population growth in adjacent cities (from approximately 38,000 people in 1880 to over a million in 1999) form two dominant landscape patterns. Mining and wetland/riparian occupy the smallest amount of land use acres compared to urban, transportation, or water reservoir activities in the Clear Creek aggregate reserve study area. Four types of reclaimed pits along Clear Creek were determined: water storage facilities, wildlife/greenbelt space, multiple-purpose reservoirs, and 'hidden scenery.' The latter involves infilling gravel pits (with earth backfill, concrete rubble, or sanitary landfill) and covering the site with light industry or residential housing making the landform hard to detect as a past mine site. Easier to recognize are the strong-edged, rectilinear water reservoirs, reclaimed from off-channel sand and gravel pits that reflect the land survey grid and property boundaries. The general public may not realize softly contoured linear wildlife corridors connecting urban

  3. Pollution from aircraft emissions in the North Atlantic flight corridor. Overview on the results of the POLINAT project

    Energy Technology Data Exchange (ETDEWEB)

    Schumann, U.; Duerbeck, T.; Feigl, C. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Wessling (Germany); Arnold, F.; Droste-Franke, B. [Max-Planck-Inst. fuer Kernphysik, Heidelberg (Germany); Flatoy, F. [Bergen Univ. (Norway). Inst. of Geophysics; Ford, I.J. [University Coll., London (United Kingdom); Hagen, D.E.; Hopkins, A.R. [Missouri Univ., Rolla, MO (United States). Lab. for Cloud and Aerosol Sciences; Hayman, G.D. [National Environmental Technology Centre, AEA Technology, Culham (United Kingdom); and others

    1997-12-31

    The POLINAT project (phase 1) was performed 1994 to 1996 within the Environment Research Programme of the European Commission. POLINAT-2 is being performed now since April 1996. The objectives of POLINAT-1 and -2, the methods used, the measurements, and some selected results are described. Details are given on the measured background concentrations, the emission indices of several aircraft, comparisons between modelled and measured data, and the impact of the emissions within the North Atlantic flight corridor. (author) 21 refs.

  4. Assessing Habitat Quality of Forest-Corridors through NDVI Analysis in Dry Tropical Forests of South India: Implications for Conservation

    OpenAIRE

    Paramesha Mallegowda; Ganesan Rengaian; Jayalakshmi Krishnan; Madhura Niphadkar

    2015-01-01

    Most wildlife habitats and migratory routes are extremely threatened due to increasing demands on forestland and forest resources by burgeoning human population. Corridor landscape in Biligiri Rangaswamy Temple Tiger Reserve (BRT) is one among them, subjected to various anthropogenic pressures. Human habitation, intensive farming, coffee plantations, ill-planned infrastructure developments and rapid spreading of invasive plant species Lantana camara, pose a serious threat to wildlife habitat ...

  5. Acidic Deposition along the Appalachian Trail Corridor and its Effects on Acid-Sensitive Terrestrial and Aquatic Resources

    Science.gov (United States)

    Lawrence, G. B.; Sullivan, T. J.; Burns, D. A.; Bailey, S. W.; Cosby, B. J., Jr.; Dovciak, M.; Ewing, H. A.; McDonnell, T. C.; Riemann, R.; Quant, J.; Rice, K. C.; Siemion, J.; Weathers, K. C.

    2015-12-01

    The Appalachian National Scenic Trail (AT) spans 3,500 km from Georgia to Maine. Over its length, the trail passes through a corridor with wide variations in climate, bedrock type, soils, and stream water quality. These factors create a diverse range of ecosystems. The health of these ecosystems is a cause for concern because the AT passes through the heavily populated eastern U.S. with its many sources of sulfur (S) and nitrogen (N) emissions that produce acidic deposition. To address concerns about the health of the AT, a study was designed to evaluate the condition and sensitivity of the AT corridor with respect to acidic deposition. Collections of stream water (265 sites), soil (60 sites), tree cores (15 sites) and atmospheric deposition samples (4 sites) were made along with understory and overstory vegetation measurements (30 sites) over the full trail length within a 40 km-wide corridor. Existing data on atmospheric deposition, geology, vegetation, stream chemistry, and soil chemistry were also used in the analysis. Mean acid-neutralizing capacity (ANC) was lowest in the streams in the North section, intermediate in the Central section and highest the South section, despite the South having the highest acid rain levels. At least 40% of the study streams exhibited pH and/or Ali measurements that indicated potential harm to biota. Approximately 70% of the soil sites had values of base saturation under 20%, the threshold below which acidic deposition can mobilize inorganic aluminum (Ali), the form harmful to terrestrial and aquatic life. Compositional similarity of understory and canopy species was positively correlated with acidic deposition, suggesting that during past decades, species poorly adapted to acidic deposition were replaced with tolerant species. Target loads modeling indicated that exceedance of sulfur target loads to achieve stream ANC = 50 μeq/L by the year 2100occurred throughout the trail corridor.

  6. Exploring empowerment within the Gullah Geechee cultural heritage corridor: implications for heritage tourism development in the Lowcountry

    Science.gov (United States)

    B. Bynum Boley; Cassandra Johnson Gaither

    2015-01-01

    While scholarship on the Gullah Geechee (GG) people has been extensive, little research has examined heritage tourism’s potential to empower or disempower the GG. In an attempt to shed light on this, the Gullah Geechee Cultural Heritage Corridor (GGCHC) was chosen as a case-study site because of its 2006 designation by Congress to protect and promote the unique...

  7. Planning Landscape Corridors in Ecological Infrastructure Using Least-Cost Path Methods Based on the Value of Ecosystem Services

    Directory of Open Access Journals (Sweden)

    Jung A Lee

    2014-10-01

    Full Text Available Ecosystem service values have rarely been incorporated in the process of planning ecological infrastructure for urban areas. Urban ecological infrastructure is a network system of natural lands and waters that provides ecosystem services. The purpose of this study was to design landscape corridors that maximize the value of ecosystem services in ecological infrastructure planning. We explored the optimal corridors to enhance the connectivity among landscape elements to design an ecological infrastructure for the city of Gwacheon, South Korea, as an example of a small urban area. We calculated the value of ecosystem services using standardized estimation indices based on an intensive review of the relevant literature and employed the least-cost path method to optimize the connectivity of landscape structural elements. The land use type in the city with the highest estimated value of ecosystem services was the riparian zone (i.e., 2011 US$7,312.16/ha. Given areal coverage of all land use types, the estimated value of developed area open spaces was 2011 US$899,803.25, corresponding to the highest contribution to the total value of ecosystem services. Therefore, the optimal configured dispersal corridors for wildlife were found from the riparian zones (source area to the developed area open spaces (destination area in the city. Several challenges remain for improving the estimation of the value of ecosystem services and incorporating these ecosystems in ecological infrastructure planning. Nonetheless, the approaches taken to estimate the value of ecosystem services and design landscape corridors in this study may be of value to future efforts in urban ecological infrastructure planning.

  8. Diet composition of common leopards in Bardia National Park and the adjacent buffer zones and habitat corridor in Nepal

    OpenAIRE

    Deo, Rima

    2014-01-01

    The common Leopard (Panthera pardus) is the most widely distributed species among the large felids. It is a great challenge to manage their depredation on livestock at global level. In this study, I examined spatiotemporal patterns of leopard diet composition in Bardia National Park, Nepal, the buffer zones surrounding the park and a recently established habitat corridor that extends towards a protected area in India. Based on analyses of leopard scat contents, I investigated how the proporti...

  9. [Seasonal variation and spatial distribution of typical organochlorine pesticides in the atmosphere of Hexi Corridor and Lanzhou, northwest China].

    Science.gov (United States)

    Ding, Zhong-Yuan; Mao, Xiao-Xuan; Ma, Zi-Long; Tian, Hui; Guo, Qiang; Huang, Tao; Gao, Hong; Li, Jun; Zhang, Gan

    2013-04-01

    Air samples were seasonally collected in Hexi Corridor and Lanzhou, Gansu province, using polyurethane foam (PUF) based passive air samplers for a year and determined hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs). Atmospheric concentrations of sigma HCHs (alpha-HCH +beta-HCH +gamma-HCH +delta-HCH) and sigma DDTs (p,p'-DDT + o,p'-DDT + p,p'-DDE + p,p'-DDD) were 86.22 pg x m(-3) and 34.06 pg x m(-3) in Hexi Corridor and Lanzhou with background concentrations of 54.41 pg x m(-3) and 21.56 pg x m(-3), respectively, which were lower than previously reported values elsewhere. In general, the seasonal pollution characteristics of sigma HCHs and sigma DDTs exhibited higher levels with the average concentrations of 127.4 pg x m(-3) and 47.06 pg x m(-3) in autumn, respectively. Furthermore, relatively higher residual concentrations of HCHs and DDTs were found in Jiuquan, Anxi and Zhangye, relating to their more arable lands and more intensively historical usage. Source apportionment indicated HCHs were mainly originated from historical technical-HCHs residues and recent Lindane usage. Recently introduced technical-DDTs was highly responsible for DDTs contamination, whereas the higher concentrations of o,p'-DDT observed in Jiuquan and Anxi may be attributed to dicofol usage. In addition, human exposure to HCHs and DDTs in Hexi Corridor and Lanzhou via inhalation could be relatively low.

  10. Conditions and processes affecting sand resources at archeological sites in the Colorado River corridor below Glen Canyon Dam, Arizona

    Science.gov (United States)

    East, Amy E.; Collins, Brian D.; Sankey, Joel B.; Corbett, Skye C.; Fairley, Helen C.; Caster, Joshua

    2016-05-17

    This study examined links among fluvial, aeolian, and hillslope geomorphic processes that affect archeological sites and surrounding landscapes in the Colorado River corridor downstream from Glen Canyon Dam, Arizona. We assessed the potential for Colorado River sediment to enhance the preservation of river-corridor archeological resources through aeolian sand deposition or mitigation of gully erosion. By identifying locally prevailing wind directions, locations of modern sandbars, and likely aeolian-transport barriers, we determined that relatively few archeological sites are now ideally situated to receive aeolian sand supply from sandbars deposited by recent controlled floods. Whereas three-fourths of the 358 river-corridor archeological sites we examined include Colorado River sediment as an integral component of their geomorphic context, only 32 sites currently appear to have a high degree of connectivity (coupled interactions) between modern fluvial sandbars and sand-dominated landscapes downwind. This represents a substantial decrease from past decades, as determined by aerial-photograph analysis. Thus, we infer that recent controlled floods have had a limited, and declining, influence on archeological-site preservation.

  11. Assessing Habitat Quality of Forest-Corridors through NDVI Analysis in Dry Tropical Forests of South India: Implications for Conservation

    Directory of Open Access Journals (Sweden)

    Paramesha Mallegowda

    2015-02-01

    Full Text Available Most wildlife habitats and migratory routes are extremely threatened due to increasing demands on forestland and forest resources by burgeoning human population. Corridor landscape in Biligiri Rangaswamy Temple Tiger Reserve (BRT is one among them, subjected to various anthropogenic pressures. Human habitation, intensive farming, coffee plantations, ill-planned infrastructure developments and rapid spreading of invasive plant species Lantana camara, pose a serious threat to wildlife habitat and their migration. Aim of this work is to create detailed NDVI based land change maps and to use them to identify time-series trends in greening and browning in forest corridors in the study area and to identify the drivers that are influencing the observed changes. Over the four decades in BRT, NDVI increased in the core area of the forest and reduced in the fringe areas. The change analysis between 1973 and 2014 shows significant changes; browning due to anthropogenic activities as well as natural processes and greening due to Lantana spread. This indicates that the change processes are complex, involving multiple driving factors, such as socio-economic changes, high population growth, historical forest management practices and policies. Our study suggests that the use of updated and accurate change detection maps will be useful in taking appropriate site specific action-oriented conservation decisions to restore and manage the degraded critical wildlife corridors in human-dominated landscape.

  12. Geospatial and machine learning techniques for wicked social science problems: analysis of crash severity on a regional highway corridor

    Science.gov (United States)

    Effati, Meysam; Thill, Jean-Claude; Shabani, Shahin

    2015-04-01

    The contention of this paper is that many social science research problems are too "wicked" to be suitably studied using conventional statistical and regression-based methods of data analysis. This paper argues that an integrated geospatial approach based on methods of machine learning is well suited to this purpose. Recognizing the intrinsic wickedness of traffic safety issues, such approach is used to unravel the complexity of traffic crash severity on highway corridors as an example of such problems. The support vector machine (SVM) and coactive neuro-fuzzy inference system (CANFIS) algorithms are tested as inferential engines to predict crash severity and uncover spatial and non-spatial factors that systematically relate to crash severity, while a sensitivity analysis is conducted to determine the relative influence of crash severity factors. Different specifications of the two methods are implemented, trained, and evaluated against crash events recorded over a 4-year period on a regional highway corridor in Northern Iran. Overall, the SVM model outperforms CANFIS by a notable margin. The combined use of spatial analysis and artificial intelligence is effective at identifying leading factors of crash severity, while explicitly accounting for spatial dependence and spatial heterogeneity effects. Thanks to the demonstrated effectiveness of a sensitivity analysis, this approach produces comprehensive results that are consistent with existing traffic safety theories and supports the prioritization of effective safety measures that are geographically targeted and behaviorally sound on regional highway corridors.

  13. SHRUBBY TREE COMPONENT OF RIPARIAN CORRIDORS IN RESTORATION AND NATURAL REMAINING AREAS OF MATRIX FORESTRY, RIO NEGRINHO, SC STATE

    Directory of Open Access Journals (Sweden)

    Eliziane Carla Scariot

    2014-06-01

    Full Text Available http://dx.doi.org/10.5902/1980509814578The aim of this study was to analyze the shrubby tree component in riparian corridors in restoration process and natural remainders in a matrix forestry. We identified the richness, diversity, dispersal and pollination syndromes of the individuals and estimate the floristic similarity. The study was conducted at the producing farm of Pinus spp. wood Santa Alice, located in Rio Negrinho city, Santa Catarina state, Brazil. We adopted the center-quarter method for survey the shrubby tree component in four sample groups: CA (advanced stage of riparian corridors vegetation, CR (riparian corridors in restoration, MA (advanced stage of natural remaining, MI (intermediate stage of natural remaining. We found the highest richness and diversity index in MA and CR. Regarding the number of individuals, the dispersal and pollination syndromes predominant in all sample groups were zoochory and zoophilia. CR and CA had the highest percentage of floristic similarity while MA and MI did not form clusters. The sample group CR has composition, richness and diversity more similar to CA. This indicates that the restoration of riparian zones has conditions to rescue the components and the interactions of an ecological community.

  14. Inventory of Invasive Plant Species along the corridor of Kawah Ijen Nature Tourism Park, Banyuwangi, East Java

    Directory of Open Access Journals (Sweden)

    Lia Hapsari

    2014-01-01

    Full Text Available A field survey was conducted in November 2013 to inventory invasive plant species present along the corridor of Kawah Ijen Nature Tourism Park exploratively. Result showed that there were 11 plant species found abundantly along the corridor. Typical native species were dominated by Cyathea contaminans, Casuarina junghuhniana and Vaccinium varingiaefolium. Three species were determined as invasive alien species i.e. Chromolaena odorata, Acacia decurrens and Blumea lacera whereas five species were determined as native species but potential invaders i.e. Rubus moluccanus, Melastoma malabatrichum, Polygonum barbatum, Debregeasia longifolia and Pteridium aquilinum. In term of tourism particularly on nature-based destinations enable moving in and out of invasive alien species due to opening the access of some natural protected areas. The environmental impact of an alien species whether it becomes invasive at its destination depends on its biological key point,  what ecological role the species may play, and on additional factors such as its tolerance of the gross features of the environment in the new range. Keyword: invasive plants, corridor, Kawah Ijen, Nature Tourism Park, Banyuwangi

  15. Pipeline corridors through wetlands - impacts on plant communities: Bayou Grand Cane, De Soto Parish, Louisiana. Topical report, August 1991--July 1993

    Energy Technology Data Exchange (ETDEWEB)

    Shem, L.M.; Zimmerman, R.E.; Hayes, D. [Argonne National Lab., IL (United States); Van Dyke, G.D. [Argonne National Lab., IL (United States)]|[Trinity Christian College, Palos Heights, IL (United States)

    1994-12-01

    The goal of the Gas Research Institute Wetland Corridors Program is to document impacts of existing pipeline on the wetlands they traverse. To accomplish this goal, 12 existing wetland crossings were surveyed. These sites varied in elapsed time since pipeline construction, wetland type, pipeline installation techniques, and night of-way (ROW) management practices. This report presents the results of a survey conducted over the period of August 12-13, 1991, at the Bayou Grand Cane crossing in De Soto Parish, Louisiana, where a pipeline constructed three years prior to the survey crosses the bayou through mature bottomland hardwoods. The sit was not seeded or fertilized after construction activities. At the time of sampling, a dense herb stratum (composed of mostly native species) covered the 20-m-wide ROW, except within drainage channels. As a result of the creation of the ROW, new habitat was created, plant diversity increased, and forest habitat became fragmented. The ROW must be maintained at an early stage of succession to allow access to the pipeline however, impacts to the wetland were minimized by decreasing the width of the ROW to 20 m and recreating the drainage channels across the ROW. The canopy trees on the ROW`s edge shaded part of the ROW, which helped to minimize the effects of the ROW.

  16. Pipeline corridors through wetlands - summary of seventeen plant-community studies at ten wetland crossings. Topical report, February 1990--August 1994

    Energy Technology Data Exchange (ETDEWEB)

    Van Dyke, G.D. [Argonne National Lab., IL (United States)]|[Trinity Christian College, Palos Heights, IL (United States); Shem, L.M.; Wilkey, P.L.; Zimmerman, R.E.; Alsum, S.K. [Argonne National Lab., IL (United States)

    1994-12-01

    As part of the Gas Research Institute Wetland Corridors Program, Argonne National Laboratory conducted field studies on 10 wetland crossings located in six states to document impacts of natural gas pipeline rights-of-way (ROWS) on 15 wetland plant communities. This study is unique in the number, range, ages, and variety of wetland crossings surveyed and compared. Vegetation data and recorded observations were analyzed to reveal patterns associated with age, installation technology, maintenance practices, and wetland type. This report summarizes the findings of this study. Results revealed that ROWs of pipelines installed according to recent wetland regulations rapidly revegetated with dense and diverse plant communities. The ROW plant communities were similar to those in the adjacent natural areas in species richness, wetland indicator values, and percentages of native species. The ROW plant communities developed from naturally available propagules without fertilization, liming, or artificial seeding. ROWs contributed to increased habitat and plant species diversity in the wetland. There was little evidence that they degrade the wetland by providing avenues for the spread of invasive and normative plant species. Most impacts are temporal in nature, decreasing rapidly during the first several years and more slowly thereafter to the extent permitted by maintenance and other ROW activities.

  17. Introduction to corridor selection & assessment for Bus Rapid Transit System (BRTS in Hyderabad

    Directory of Open Access Journals (Sweden)

    Bhanu Kireeti Chanda

    2014-06-01

    Full Text Available Bus rapid transit system is an innovation and it is up gradation to the present transport system. BRT is affordable, adaptable and cost effective. The term of rapid transit system means a form of high speed urban passenger transportation. Here, the mode of transportation is bus hence it is called as bus rapid transit system (BRTS. Transportation facilities and the system will be different form different countries. Especially for the developing countries, transportation is a problem and BRT is the best way to overcome it. If a country gets richer the development will be seen in different aspects like education, industry, science and technology etc., except transport which will get worse. There are many ways to get rid of these traffic issues and transport problems. What attracted the countries to install BRT is the bus way concept as that it can cover whole city and is cheaper than the rail. BRT is a high speed rapid transit system using high capacity vehicles, physically separated bus ways, modern station with electronic fare collection, rapid boarding and high service frequency which result more passengers and less congestion. This paper presents an overview of BRTS and corridor selection & assessment for it in Hyderabad through surveys etc.

  18. Environmental and social risk evaluation of overseas investment under the China-Pakistan Economic Corridor.

    Science.gov (United States)

    Zhang, Ruilian; Andam, Francis; Shi, Guoqing

    2017-06-01

    Along with the further implementation of the "One Belt, One Road" initiative and the promotion of the China-Pakistan Economic Corridor (CPEC), the construction of the CPEC will likely face challenges owing to differences between China and Pakistan in politics, economics, culture, religion, language, customs, environmental management systems, environmental protection laws, social management systems, and social management regulations. To address potential environmental and social risks associated with Chinese enterprises as they invest in the CPEC region, this paper examines previous studies addressing topics such as the environmental and social safeguards of international institutions and Pakistan's domestic environmental and social management requirements. We then systematically identify the environmental and social risk factors involved in CPEC construction, which cover risks regarding water, air, soil, noise, biodiversity, politics, economics, culture, technology, and individuals. By establishing and calculating these risks and using a multi-fuzzy comprehensive evaluation model, we found that noise and individual risks belong to a medium risk category, while others belong to a higher risk category. In view of these risks, the Chinese government must create a friendly and peaceful environment for Chinese enterprises to invest in the CPEC region, and Chinese enterprises must adopt a development strategy of strength and capacity building and establish enterprises capable of addressing environmental and social issues during the investment process. All stakeholders must understand that if no determined and diligent steps are taken, CPEC construction might be doomed for failure from the start.

  19. Application of Lean Agile Resilient Green Paradigm Framework on China Pakistan Economic Corridor: A Case Study

    Directory of Open Access Journals (Sweden)

    KHAN RAI WAQASAZFAR

    2017-07-01

    Full Text Available China has recently emerged as the technological and economic giant and an attractive place for investment for MCNs (Multi-National Companies. Many of the high ranked MNC?s have shifted their production facilities to China due to low production cost.Finished products are transported through sea routes passing through Singapore and Sri Lanka, to different Middle Eastern, European and American countries. This major transition has lead to complete transformation of the global SC (Supply Chain;which resulted into extended transportation, distances and led time,thus affecting the four paradigms of SC i.e. lean, agile, resilient and green. Effective integration of all of these paradigms poses a significant challenge for the academia and industry related to SC.The common and critical success factors among these paradigms are reduction in transportation distances and most importantly lead time. Scenario planning technique is used in this study to analyze different trade routes originating from central China. CPEC (China Pakistan Economic Corridor was identified as the most feasible and economical route owing to its reduced transportation distance and led time. CPEC route also provides us an opportunity to perform trade-offs between the four paradigms; focusing primarily on the critical success factors. These tradeoffs provide us a common ground which lead us to propose a new LARG (Lean Agile Resilient Green framework. This framework was further validated with the help of results obtained from CPEC case study using scenario planning technique

  20. Determination of bioclimatic comfort in Erzurum-Rize expressway corridor using GIS

    Energy Technology Data Exchange (ETDEWEB)

    Zengin, Murat; Karahan, Faris [Department of Landscape Architecture, Faculty of Agriculture, Atatuerk University, 25240 Erzurum (Turkey); Kopar, Ibrahim [Department of Physical Geography, Faculty of Literature, Atatuerk University, 25240 Erzurum (Turkey)

    2010-01-15

    In this study, topographical and climatical conditions are prescinded all along Erzurum-Rize expressway corridors to appoint the areas which have bioclimatic comfort in summer season (June, July, August). For this purpose, the climate data (temperature, relative humidity, wind speed) from nine different stations was entered in the digital data base. By dint of ArcGIS 9.1 software, climatic data were analysed and numerological maps were produced by Inverse Distance Weighted (IDW) interpolation method. As a method, bioclimatically comfortable areas consists of: relative humidity between 30 and 65%, temperature between 15 and 20 C, and wind speed up to 5 m/s. The maps were scored as 0 for uncomfortable and 1 for comfortable and superposed, and bioclimatic comfort area (temperature: 1-relative humidity: 1-wind speed: 1) were determined. Besides, topographic factors were appreciated. As a result of this study, it is concerned that the area (452749 ha. % 63); beginning from south of the Mountains Mescit which is started by Black Sea coastline to Mountain Mescit (3230 m) is out of bioclimatic comfort region; the Erzurum depression (1758 m) beginning from the Mountains Mescit has been determined that area has bioclimatic comfort conditions. As a consequence, it is confirmed that one of the ideal area which has bioclimatic comfort is the Erzurum depression area in Turkey. (author)

  1. Three Different Approaches for Localization in a Corridor Environment by Means of an Ultrasonic Wide Beam

    Directory of Open Access Journals (Sweden)

    Luigi Spedicato

    2013-03-01

    Full Text Available In this paper the authors present three methods to detect the position and orientation of an observer, such as a mobile robot, with respect to a corridor wall. They use an inexpensive sensor to spread a wide ultrasonic beam. The sensor is rotated by means of an accurate servomotor in order to propagate ultrasonic waves towards a regular wall. Whatever the wall material may be the scanning surface appears to be an acoustic reflector as a consequence of low air impedance. The realized device is able to give distance information in each motor position and thus permits the derivation of a set of points as a ray trace‐scanner. The dataset contains points lying on a circular arc and relating to strong returns. Three different approaches are herein considered to estimate both the slope of the wall and its minimum distance from the sensor. Slope and perpendicular distance are the parameters of a target plane, which may be calculated in each observer’s position to predict its new location. Experimental tests and simulations are shown and discussed by scanning from different stationary locations. They allow the appreciation of the effectiveness of the proposed approaches.

  2. The effect of perception anisotropy on particle systems describing pedestrian flows in corridors

    CERN Document Server

    Gulikers, Lennart; Muntean, Adrian; Lyulin, Alexey

    2012-01-01

    We consider a microscopic model (a system of self-propelled particles) to study the behaviour of a large group of pedestrians walking in a corridor. Our point of interest is the effect of anisotropic interactions on the global behaviour of the crowd. The anisotropy we have in mind reflects the fact that people do not perceive (i.e. see, hear, feel or smell) their environment equally well in all directions. The dynamics of the individuals in our model follow from a system of Newton-like equations in the overdamped limit. The instantaneous velocity is modelled in such a way that it accounts for the angle under which an individual perceives another individual. We investigate the effects of this perception anisotropy by means of extensive simulations, very much in the spirit of molecular dynamics. We define a number of characteristic quantifiers (including the polarization index and Morisita index) that serve as measures for e.g. organization and clustering, and we use these to investigate the influence of anisot...

  3. An ecological basis for future fish habitat restoration efforts in the Huron-Erie Corridor

    Science.gov (United States)

    Hondorp, Darryl W.; Roseman, Edward F.; Manny, Bruce A.

    2014-01-01

    This perspective describes the major natural and anthropogenic forces driving change in the abundance and quality of fish habitats in the Huron-Erie Corridor (HEC), the Great Lakes connecting channel comprised of the St. Clair River, the Lake St. Clair, and the Detroit River. Channels connecting the Laurentian Great Lakes discharge large volumes of water equal to or greater than most other large rivers in the world that is of consistent high quality and volume, all year. Owing to creation of the St. Lawrence Seaway through the Great Lakes, the connecting channels have been modified by dredging over 200 km of deep-draft shipping lanes with a maintained depth of no less than 8.2 m. Combined with modification of their shorelines for housing and industries, use of the connecting channels for discharges of industrial and municipal wastes and shipping has resulted in numerous beneficial use impairments, such as restrictions on fish and wildlife consumption, degradation of fish and wildlife populations, and losses of fish and wildlife habitat. Various options for remediation of native fish populations and their habitats in the Great Lakes connecting channels, including construction of spawning habitat for threatened and high-value food fishes, such as lake sturgeon (Acipenser fulvescens), walleye (Sander vitreus), and lake whitefish (Coregonus clupeaformis), have been implemented successfully in two of the channels, and form the basis for further recommended research described in this article.

  4. Melampyrum Cristatum L. – A Rare River Corridor Plant in Wielkopolska and Poland

    Directory of Open Access Journals (Sweden)

    Stachnowicz Wojciech

    2013-12-01

    Full Text Available Melampyrum cristatum is an extremely rare, native, hemi-parasitic, vascular plant, recently considered to be extinct in Poland. The article presents data concerning new localities of the species recorded in 2007-2012 in the valley of the River Warta (Wielkopolska, Poland. Local distribution of M. cristatum in the Natura 2000 sites: PLH300012 - Rogalińska Dolina Warty (ca. 147.5 sq. km and PLH300053 - Lasy Żerkowsko-Czeszewskie (ca. 71.6 sq. km, as well as its updated regional (in Wielkopolska and national (Poland ranges are shown on maps and interpreted on the background of the geomorphic diversity of occupied habitats. The results suggest that in Poland the species is distributed mainly along valleys of large, lowland rivers, which corresponds with its ‘River Corridor Plant’ status in Central Europe. The species rarity is discussed considering its outline phytocoenological scale (comprising various plant communities within 6 syntaxonomical classes, the riverine distribution pattern and chosen biological features. Natural habitat heterogeneity along with changeable water regime in floodplains, as well as potential limitations of myrmecochoric seed dispersal, may constitute potential reasons for the species low frequency

  5. Protect Anadromous Salmonids in the Mainstem Corridor, Monitoring and Evaluation, Annual Report 200-2001.

    Energy Technology Data Exchange (ETDEWEB)

    Vigg, Steven; Johnson, John

    2002-02-01

    In this annual Monitoring & Evaluation (M&E) report to the Bonneville Power Administration (BPA), we summarize significant activities and performance measures resultant from enhanced protection by Columbia River Inter-Tribal Fisheries Enforcement (CRITFE) in the mainstem corridor (BPA Project 2000-056). This report covers the Fiscal Year (FY) 2000 performance period -- May 15, 2000 to May 14, 2001. Quarterly progress reports have previously been submitted to BPA and are posted on the M&E Web site (www.Eco-Law.net) -- for the time period April-December 2000 (Vigg 2000b,c,d) and for the period January-June 2001 (Vigg 2001a,b). We also present comprehensive data representing the first quarter of year 2000 in this report for a pre-project comparison. In addition, we have analyzed specific annual enforcement statistics to evaluate trends during the baseline period 1996-2000. Additional statistics and more years of comprehensive baseline data are now being summarized, and will be presented in future M&E annual reports--to provide a longer time series for evaluation of trends in input, output and outcome performance standards.

  6. Survey of transmission line corridors. [Data on delays in transmission line construction

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-05

    The intent of this study is to determine the extent of delays experienced in planning and constructing transmission lines in the continental United States. The reasons for the delays are identified for each line studied and their effect on the total electrical system is sought. Data was collected for 136 different lines either recently built or currently under study. Statistics were developed for each line in several categories and comparisons of lines delayed were made by company, area served and generation capacity. From the study presented here it was found that: right-of-way acquisition procedures including condemnation and easement negotiation practices delay more projects than local, state and federal regulatory requirements combined; load growth reductions particularly in the east have reduced the impact of regulatory delays; the south, southeast and southwestern areas of the country experience fewer delays in constructing transmission lines than the more populated states, and the cost for corridor delays was responded to for only 17 of the 142 projects surveyed. By far the most costly delay is the expense of condemning land for transmission right-of-way.

  7. PRECIPITATION, A PRESENT-DAY MODELLING FACTOR IN THE ORĂŞTIE CORRIDOR

    Directory of Open Access Journals (Sweden)

    CĂTĂLINA MĂRCULEŢ

    2014-10-01

    Full Text Available This Corridor, which extends between the confluence of the Mureş River and its tributaries Sebeş and the Strei, is subjected to vast modelling processes (rain-induced weathering, surface erosion, gullying, torrential activity and landsliding, triggered largely by precipitation. Annual mean values are over 500 mm; however, maximum precipitation/24 hrs of up to 75 mm have the greatest impact. Slope processes are enhanced with precipitation of over 10 mm / day, more frequently occurring from June through to September. The analysis of the Fournier Index (an indicator of rain-induced erosion has revealed that maximum values were recorded by the Sebeş and Deva weather station in June and July. Large quantities of torrential and lasting precipitation are a frequent occurrence also during transitional seasons, having the same detrimental effects, mostly in spring when harvested soils are already moist from snowmelt. Whenever heavy rains fall after long periods of dryness, the soil is severely impaired by raininduced denudation, especially on slopes cultivated with hoeing plants.

  8. Quantifying forest vertical structure to determine bird habitat quality in the Greenbelt Corridor, Denton, TX

    Science.gov (United States)

    Matsubayashi, Shiho

    This study presents the integration of light detection and range (LiDAR) and hyperspectral remote sensing to create a three-dimensional bird habitat map in the Greenbelt Corridor of the Elm Fork of the Trinity River. This map permits to examine the relationship between forest stand structure, landscape heterogeneity, and bird community composition. A biannual bird census was conducted at this site during the breeding seasons of 2009 and 2010. Census data combined with the three-dimensional map suggest that local breeding bird abundance, community structure, and spatial distribution patterns are highly influenced by vertical heterogeneity of vegetation surface. For local breeding birds, vertical heterogeneity of canopy surface within stands, connectivity to adjacent forest patches, largest forest patch index, and habitat (vegetation) types proved to be the most influential factors to determine bird community assemblages. Results also highlight the critical role of secondary forests to increase functional connectivity of forest patches. Overall, three-dimensional habitat descriptions derived from integrated LiDAR and hyperspectral data serve as a powerful bird conservation tool that shows how the distribution of bird species relates to forest composition and structure at various scales.

  9. Fogwater Chemistry and Air Quality in the Texas-Louisiana Gulf Coast Corridor

    Science.gov (United States)

    Kommalapati, R. R.; Raja, S.; Ravikrishna, R.; Murugesan, K.; Collett, J. L.; Valsaraj, K.

    2007-05-01

    The presence of fog water in polluted atmosphere can influence atmospheric chemistry and air quality. The study of interactions between fog water and atmospheric gases and aerosols are very important in understanding the atmospheric fate of the pollutants. In this Study several air samples and fogwater samples were collected in the heavily industrialized area of Gulf Coast corridor( Houston, TX and Baton Rouge, LA). A total of 32 fogwater samples were collected, comprising of nine fog events in Baton Rouge (Nov 2004 to Feb 2005) and two fog events in Houston (Feb, 2006), during the fog sampling campaigns. These samples were analyzed for pH, total and dissolved carbon, major inorganic ions, organic acids, and aromatics, aldehydes, VOCs, and linear alkanes organic compounds. Fogwater samples collected in Houston show clear influence of marine and anthropogenic environment, while Baton Rouge samples reveal a relatively less polluted environment. Also, a time series observation of air samples indicated that fog event at the monitoring site impacted the air concentrations of the pollutants. This is attributed to presence of surface active organic matter in fog water.

  10. Three Different Approaches for Localization in a Corridor Environment by Means of an Ultrasonic Wide Beam

    Directory of Open Access Journals (Sweden)

    Luigi Spedicato

    2013-03-01

    Full Text Available In this paper the authors present three methods to detect the position and orientation of an observer, such as a mobile robot, with respect to a corridor wall. They use an inexpensive sensor to spread a wide ultrasonic beam. The sensor is rotated by means of an accurate servomotor in order to propagate ultrasonic waves towards a regular wall. Whatever the wall material may be the scanning surface appears to be an acoustic reflector as a consequence of low air impedance. The realized device is able to give distance information in each motor position and thus permits the derivation of a set of points as a ray trace-scanner. The dataset contains points lying on a circular arc and relating to strong returns. Three different approaches are herein considered to estimate both the slope of the wall and its minimum distance from the sensor. Slope and perpendicular distance are the parameters of a target plane, which may be calculated in each observer's position to predict its new location. Experimental tests and simulations are shown and discussed by scanning from different stationary locations. They allow the appreciation of the effectiveness of the proposed approaches.

  11. Mitochondrial haplogroup C4c: a rare lineage entering America through the ice-free corridor?

    Science.gov (United States)

    Hooshiar Kashani, Baharak; Perego, Ugo A; Olivieri, Anna; Angerhofer, Norman; Gandini, Francesca; Carossa, Valeria; Lancioni, Hovirag; Semino, Ornella; Woodward, Scott R; Achilli, Alessandro; Torroni, Antonio

    2012-01-01

    Recent analyses of mitochondrial genomes from Native Americans have brought the overall number of recognized maternal founding lineages from just four to a current count of 15. However, because of their relative low frequency, almost nothing is known for some of these lineages. This leaves a considerable void in understanding the events that led to the colonization of the Americas following the Last Glacial Maximum (LGM). In this study, we identified and completely sequenced 14 mitochondrial DNAs belonging to one extremely rare Native American lineage known as haplogroup C4c. Its age and geographical distribution raise the possibility that C4c marked the Paleo-Indian group(s) that entered North America from Beringia through the ice-free corridor between the Laurentide and Cordilleran ice sheets. The similarities in ages andgeographical distributions for C4c and the previously analyzed X2a lineage provide support to the scenario of a dual origin for Paleo-Indians. Taking into account that C4c is deeply rooted in the Asian portion of the mtDNA phylogeny and is indubitably of Asian origin, the finding that C4c and X2a are characterized by parallel genetic histories definitively dismisses the controversial hypothesis of an Atlantic glacial entry route into North America.

  12. Survey of transmission line corridors. [Data on delays in transmission line construction

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-05

    The intent of this study is to determine the extent of delays experienced in planning and constructing transmission lines in the continental United States. The reasons for the delays are identified for each line studied and their effect on the total electrical system is sought. Data was collected for 136 different lines either recently built or currently under study. Statistics were developed for each line in several categories and comparisons of lines delayed were made by company, area served and generation capacity. From the study presented here it was found that: right-of-way acquisition procedures including condemnation and easement negotiation practices delay more projects than local, state and federal regulatory requirements combined; load growth reductions particularly in the east have reduced the impact of regulatory delays; the south, southeast and southwestern areas of the country experience fewer delays in constructing transmission lines than the more populated states, and the cost for corridor delays was responded to for only 17 of the 142 projects surveyed. By far the most costly delay is the expense of condemning land for transmission right-of-way.

  13. Acoustic Telemetry, Cape Hatteras, and ocean Migratory Corridors: Defining Critical Habitats

    Directory of Open Access Journals (Sweden)

    Roger A. Rulifson

    2015-11-01

    Full Text Available North Carolina continental shelf waters are being targeted for development for wind farms and for oil and gas exploration. The main site for the latter is only 38 miles from Cape Hatteras, a major topographic feature that changes the dynamics of near-shore large ocean currents including the Labrador Current and Gulf Stream. The Cape constricts shelf habitat and restricts the migratory corridors of highly migratory species. The Hatteras Acoustic Array just south of the Cape indicates that this area is heavily used by species of concern year-around. Atlantic sturgeon Acipenser oxyrhynchus migrate southward through Hatteras Bight in the fall and northward in the spring; some remain in the area throughout the winter months. Sandbar Sharks, Sand Tiger Sharks, and some Atlantic Sturgeon seem to migrate to Hatteras Bight and remain in the area throughout the winter, while other Atlantic sturgeon and White Sharks tend to migrate through Hatteras Bight on the way to other overwintering grounds. The period November through April seems to be the most critical period for these four species. Agencies need to expand the area of focus for these studies, as well as gather new information about resident species and marine mammals, before science-based environmental assessment can be made.

  14. Travel modal choice analysis for traffic corridors based on decision-theoretic approaches

    Institute of Scientific and Technical Information of China (English)

    郭伟; 张毅; 尤佳轩; 胡坚明; 裴欣

    2016-01-01

    The rapid development of multimodal transportation system prompts travellers to choose multiple transportation modes, such as private vehicles or taxi, transit (subways or buses), or park-and-ride combinations for urban trips. Traffic corridor is a major scenario that supports travellers to commute from suburban residential areas to central working areas. Studying their modal choice behaviour is receiving more and more interests. On one hand, it will guide the travellers to rationally choose their most economic and beneficial mode for urban trips. On the other hand, it will help traffic operators to make more appropriate policies to enhance the share of public transit in order to alleviate the traffic congestion and produce more economic and social benefits. To analyze the travel modal choice, a generalized cost model for three typical modes is first established to evaluate each different travel alternative. Then, random utility theory (RUT) and decision field theory (DFT) are introduced to describe the decision-making process how travellers make their mode choices. Further, some important factors that may influence the modal choice behaviour are discussed as well. To test the feasibility of the proposed model, a field test in Beijing was conducted to collect the real-time data and estimate the model parameters. The improvements in the test results and analysis show new advances in the development of travel mode choice on multimodal transportation networks.

  15. [Root architecture of two desert plants in central Hexi Corridor of Northwest China].

    Science.gov (United States)

    Shan, Li-Shan; Li, Yi; Ren, Wei; Su, Shi-Ping; Dong, Qiu-Lian; Geng, Dong-Mei

    2013-01-01

    In this study, the root systems of desert plant species Reaumuria soongorica and Nitraria tangutorum in the central Hexi Corridor of Northwest China were excavated by shovel, and the characteristics of the plant root architecture were analyzed by using topology and fractal theory. The root topological indices of the two desert plants were small, and the root branching patterns were herringbone-like. The roots of the two desert plants had obvious fractal characteristics, with the fractal dimension of R. soongorica and N. tangutorum being (1.18 +/- 0.04) and (1.36 +/- 0.06), respectively. The root fractal dimension and fractal abundance were significantly positively correlated with the root average link length. The root average link lengths of the two plants were long, which enlarged the plants' effective nutrition space, and thus, made the plants adapt to the dry and infertile soil environment. The sums of the root cross-sectional areas before and after the root bifurcation of the two desert plants were equal, which verified the principle of Leonardo da Vinci. A total of 17 parameters of root architecture were analyzed by the principal component analysis. The parameters of root topological structure, numbers of root links, stepwise branching ratio, and root diameter could well present the root architecture characteristics of the two desert plants.

  16. Telecouplings in the East–West Economic Corridor within Borders and Across

    Directory of Open Access Journals (Sweden)

    Stephen J. Leisz

    2016-12-01

    Full Text Available In recent years, the concepts of teleconnections and telecoupling have been introduced into land-use and land-cover change literature as frameworks that seek to explain connections between areas that are not in close physical proximity to each other. The conceptual frameworks of teleconnections and telecoupling seek to explicitly link land changes in one place, or in a number of places, to distant, usually non-physically connected locations. These conceptual frameworks are offered as new ways of understanding land changes; rather than viewing land-use and land-cover change through discrete land classifications that have been based on the idea of land-use as seen through rural–urban dichotomies, path dependencies and sequential land transitions, and place-based relationships. Focusing on the land-use and land-cover changes taking place along the East–West Economic Corridor that runs from Dong Ha City in Quang Tri, Vietnam, through Sepon District, Savannakhet, Lao PDR, into Thailand this paper makes use of data gathered from fieldwork and remote sensing analysis to examine telecouplings between sending, receiving and spill-over systems on both sides of the Vietnam-Lao PDR border. Findings are that the telecouplings are driving changes in rural village and urban systems on both sides of the border, and are enabled by a policy environment that has sought to facilitate the cross-border transportation of goods within the region.

  17. Pedestrian movement analysis in transfer station corridor: Velocity-based and acceleration-based

    Science.gov (United States)

    Ji, Xiangfeng; Zhang, Jian; Hu, Yongkai; Ran, Bin

    2016-05-01

    In this paper, pedestrians are classified into aggressive and conservative ones by their temper. Aggressive pedestrians' walking through crowd in transfer station corridor is analyzed. Treating pedestrians as particles, this paper uses the modified social force model (MSFM) as the building block, where forces involve self-driving force, repulsive force and friction force. The proposed model in this paper is a discrete model combining the MSFM and cellular automata (CA) model, where the updating rules of the CA are redefined with MSFM. Due to the continuity of values generated by the MSFM, we use the fuzzy logic to discretize the continuous values into cells pedestrians can move in one step. With the observation that stimulus around pedestrians influences their acceleration directly, an acceleration-based movement model is presented, compared to the generally reviewed velocity-based movement model. In the acceleration-based model, a discretized version of kinematic equation is presented based on the acceleration discretized with fuzzy logic. In real life, some pedestrians would rather keep their desired speed and this is also mimicked in this paper, which is called inertia. Compared to the simple triangular membership function, a trapezoidal membership function and a piecewise linear membership function are used to capture pedestrians' inertia. With the trapezoidal and the piecewise linear membership function, many overlapping scenarios should be carefully handled and Dubois and Prade's four-index method is used to completely describe the relative relationship of fuzzy quantities. Finally, a simulation is constructed to demonstrate the effect of our model.

  18. The historical formation of the landscape in the Corridor Acapulco-Zihuatanejo

    Directory of Open Access Journals (Sweden)

    María Inés Mombelli Pierini

    2010-09-01

    Full Text Available Corridor Acapulco-Zihuatanejo is the name under the coastal plain is known, between these cities in the state of Guerrero, a strip of land located on the northwestern coast of the state which is very interesting for private investment in tourist mega-projects. This article describes the historical vicissitudes that have occurred in land use with development cycles and crises in production practices, and the consequent cultural change by successive jumps in the landscape of this territory. Using a model case study and the retrospective geography fundamentals it is possible an investigation to understand the conditions which provide a continuity of production practice or the determinant that raise a decisive break in the same practice. For this work, the landscape is a historical-cultural construction, the crop is the unity of the geographical environment which participates in the formation of the landscape within the successive production cycles, and the retrospective is a solution to questions about the future because the observation of the past suggests the question about the future, invite to leave the retrospective by the uncertainty of prospective.

  19. Extension of an iterative closest point algorithm for simultaneous localization and mapping in corridor environments

    Science.gov (United States)

    Yue, Haosong; Chen, Weihai; Wu, Xingming; Wang, Jianhua

    2016-03-01

    Three-dimensional (3-D) simultaneous localization and mapping (SLAM) is a crucial technique for intelligent robots to navigate autonomously and execute complex tasks. It can also be applied to shape measurement, reverse engineering, and many other scientific or engineering fields. A widespread SLAM algorithm, named KinectFusion, performs well in environments with complex shapes. However, it cannot handle translation uncertainties well in highly structured scenes. This paper improves the KinectFusion algorithm and makes it competent in both structured and unstructured environments. 3-D line features are first extracted according to both color and depth data captured by Kinect sensor. Then the lines in the current data frame are matched with the lines extracted from the entire constructed world model. Finally, we fuse the distance errors of these line-pairs into the standard KinectFusion framework and estimate sensor poses using an iterative closest point-based algorithm. Comparative experiments with the KinectFusion algorithm and one state-of-the-art method in a corridor scene have been done. The experimental results demonstrate that after our improvement, the KinectFusion algorithm can also be applied to structured environments and has higher accuracy. Experiments on two open access datasets further validated our improvements.

  20. Using niche-modelling and species-specific cost analyses to determine a multispecies corridor in a fragmented landscape

    Science.gov (United States)

    Zurano, Juan Pablo; Selleski, Nicole; Schneider, Rosio G.

    2017-01-01

    Misiones, Argentina, contains the largest remaining tract of Upper Paraná Atlantic Forest ecoregion; however, ~50% of native forest is unprotected and located in a mosaic of plantations, agriculture, and pastures. Existing protected areas are becoming increasingly isolated due to ongoing habitat modification. These factors, combined with lower than expected regional carnivore densities, emphasize the need to understand the effect of fragmentation on animal movement and connectivity between protected areas. Using detection dogs and genetic analyses of scat, we collected data on jaguars (Panthera onca), pumas (Puma concolor), ocelots (Leopardus pardalis), oncillas (Leopardus tigrinus), and bush dogs (Speothos venaticus) across habitats that varied in vegetation, disturbance, human proximity, and protective status. With MaxEnt we evaluated habitat use, habitat suitability, and potential species richness for the five carnivores across northern-central Misiones, Argentina. Through a multifaceted cost analysis that included unique requirements of each carnivore and varying degrees of overlap among them, we determined the optimal location for primary/secondary corridors that would link the northern-central zones of the Green Corridor in Misiones and identified areas within these corridors needing priority management. A secondary analysis, comparing these multispecies corridors with the jaguar’s unique requirements, demonstrated that this multispecies approach balanced the preferences of all five species and effectively captured areas required by this highly restricted and endangered carnivore. We emphasize the potential importance of expanding beyond a single umbrella or focal species when developing biological corridors that aim to capture the varied ecological requirements of coexisting species and ecological processes across the landscape. Detection dogs and genetic analyses of scat allow data on multiple species to be collected efficiently across multiple habitat