WorldWideScience

Sample records for air routes

  1. Effective local dynamic routing strategy for air route networks

    Institute of Scientific and Technical Information of China (English)

    Wu Wenjun; Zhao Lingxi

    2015-01-01

    With the rapid development of air transportation, network service ability has attracted a lot of attention in academe. Aiming to improve the throughput of the air route network (ARN), we propose an effective local dynamic routing strategy in this paper. Several factors, such as the rout-ing distance, the geographical distance and the real-time local traffic, are taken into consideration. When the ARN is in the normal free-flow state, the proposed strategy can recover the shortest path routing (SPR) strategy. When the ARN undergoes congestion, the proposed strategy changes the paths of flights based on the real-time local traffic information. The throughput of the Chinese air route network (CARN) is evaluated. Results confirm that the proposed strategy can significantly improve the throughput of CARN. Meanwhile, the increase in the average flying distance and time is tiny. Results also indicate the importance of the distance related factors in a routing strategy designed for the ARN.

  2. Fast 3D route-planning approach for air vehicle

    Science.gov (United States)

    Tu, Jilin; Ding, Mingyue; Zhou, Chengping; Ai, Haojun

    1997-06-01

    A fast 3-D route planning method for unmanned air vehicle is proposed which can generate physically realizable 3-D route within a reasonable time. Our method includes two steps: First, 2-D route planning generates a route which satisfies turning radius constraint(abbreviated as R-constrained below); second, 3-D route planning generates 3-D route in vertical profile of the 2-D route. To make 2-D route R-constrained, a method is proposed by supposing 2-D route of air vehicle is composed of a sequence of arc route segments and tangential points between neighboring arcs are searching nodes. 3 -D route planning is considered as optimal control problem, and its route can be determined by applying motion equations of air vehicle. The experiments show that our method can produce feasible 3-D routes within a reasonable time, and ensure the planned 3-D routes satisfy aerodynamics constraints of air vehicle.

  3. Dynamic Air Route Open-Close Problem for Airspace Management

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Dynamic airspace management plans and assigns airspace resources to airspace users on demand to increase airspace capacity. Although many studies of air traffic flow management (ATFM) have sought to optimally allocate air traffic to get the best use of given airspace resources, few studies have focused on how to build an efficient air traffic network or how to adjust the current network in real time. This paper presents an integer program model named the dynamic air route open-close problem (DROP). DROP has a cost-based objective function which takes into account constraints such as the shortest occupancy time of routes, which are not considered in ATFM models. The aim of DROP is to determine which routes will be opened to a certain user during a given time period. Simulation results show that DROP can facilitate utilization of air routes. DROP, a simplified version of an air traffic network constructing problem, is the first step towards realizing dynamic airspace management. The combination of ATFM and DROP can facilitate decisions toward more reasonable, efficient use of limited airspace resources.

  4. Air quality on bus routes in Umea, Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Sandberg, H.; Forsberg, B. [Dept. of Environmental Health and Dept. of Public Health and Clinical Medicine, Umea University SE, Umea (Sweden)

    2000-07-01

    Bus traffic in some local streets with up to 650 buses per day has resulted in complaints about air pollution and suggestions from residents that the bus routes should be changed to other streets. We have studied nitrogen dioxide and benzene concentrations at five exposed sites and at two representative control sites without bus traffic, and found no general differences in air quality. However, the site and temperature adjusted concentrations fell significantly during a strike among bus drivers. (authors)

  5. 14 CFR 71.13 - Classification of Air Traffic Service (ATS) routes.

    Science.gov (United States)

    2010-01-01

    ...) routes. 71.13 Section 71.13 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... ROUTES; AND REPORTING POINTS § 71.13 Classification of Air Traffic Service (ATS) routes. Unless otherwise specified, ATS routes are classified as follows: (a) In subpart A of this part: (1) Jet routes. (2)...

  6. Air France Offers A Second Daily Flight on Its Beijing - Paris Route

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

      Starting from 14 June 2005, Air France is adding one more daily flight on its Beijing - Paris's route. Air France customers will then have a choice of fourteen weekly flights between the two cities.……

  7. Air France Offers A Second Daily Flight on Its Beijing - Paris Route

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Starting from 14 June 2005, Air France is adding one more daily flight on its Beijing - Paris's route. Air France customers will then have a choice of fourteen weekly flights between the two cities.

  8. Airport Activity Statistics of Certificated Route Air Carriers.

    Science.gov (United States)

    1981-12-31

    CaielailIbIn1kg High Poit. Q ---. - Gronsbors/igh Point/Winston.ahig. BMVt Moolef/Brr. Hollemn AMD N. Mim -- Alfllbdo/Boliimen AID Salida Crosk. KI& -- Kaiaueaoo...Airlins, Inc. 1 Aeromech, Inc. KC 4 2 AK Altair Airlines, Inc. 2 Air California Inc. OC 2 a AL U.S. Air, ie., d&a U.S. Air 8 Air Florida, Inc. QE 2 1>4 AS...OC Air California , Inc. 36 Mid-South Aviation, Inc. VL 4 37 OZ Ozark Air Lines, Inc. 37 Midway Airlines, ic. 1L 3 38 PA Pan American World Airways

  9. Air route selection for improved air-to-ground situation assessment

    Science.gov (United States)

    Oispuu, Marc; Sciotti, Massimo; Charlish, Alexander

    2013-05-01

    Air-to-Ground Situation Assessment (SA) requires gathering information on the entities evolving on the ground (e.g., people, vehicles), and inferring the relations among them and their final intent. Several airborne sensor data might concur in the compilation of such high-level picture, which is aimed at identifying threats and promptly raising alarms. However, this process is intrinsically prone to errors: as the evidence - provided to the SA algorithm - originates from noisy sensor observations, the final outcome is also affected by uncertainty. High-level inferred variables, such as "Situation" and "Threat Level", can be seen as error-affected, incomplete estimates of the ground truth, hence they are subject to improvement by properly steering the data acquisition process. In this paper we address the problem of optimizing the air route of the sensing platform, in order to reduce the number of false declarations or the delay in threat declaration in the SA stage. Specifically, we consider the problem of detecting a hostile behavior between pairs of ground targets by exploiting track data generated from airborne bearings-only measurements. We model the optimization problem with a sequential Markov Decision Process (MDP): the platform sequentially selects the best maneuver (i.e., its acceleration vector) in order to maximize the total reward over an infinite horizon. We define the potential contribution of an action as a function of the expected environmental conditions (e.g., obscurations of the line-of-sight) and the improvement of the localization accuracy achievable for the tracked objects. We demonstrate that following the optimized trajectory the delay in the declaration of a hostile behavior between two targets is reduced at the same erroneous declaration rate.

  10. Airport Activity Statistics of Certificated Route Air Carriers

    Science.gov (United States)

    1988-12-31

    mama EA - EASTERN AIRUNES ......................... TOTAL ................. S 1090141 15147.26 2254.21 567.89 22.10 17969.36 NS 1669 AS 1091810...TOTAL MAIL MAIL VEN UELA CARACAS (LA CARLOTA ) AA- AMERICAN AIRLINES ........................ INTERNATIONAL . S 35424 332.24 .31 .31 332.55 EA- EASTERN AIR

  11. Analysis of the Chinese air route network as a complex network

    Institute of Scientific and Technical Information of China (English)

    Cai Kai-Quan; Zhang Jun; Du Wen-Bo; Cao Xian-Bin

    2012-01-01

    The air route network,which supports all the flight activities of the civil aviation,is the most fundamental infrastructure of air traffic management system.In this paper,we study the Chinese air route network (CARN) within the framework of complex networks. We find that CARN is a geographical network possessing exponential degree distribution,low clustering coefficient,large shortest path length and exponential spatial distance distribution that is obviously different from that of the Chinese airport network (CAN).Besides,via investigating the flight data from 2002 to 2010,we demonstrate that the topology structure of CARN is homogeneous,howbeit the distribution of flight flow on CARN is rather heterogeneous.In addition,the traffic on CARN keeps growing in an exponential form and the increasing speed of west China is remarkably larger than that of east China.Our work will be helpful to better understand Chinese air traffic systems.

  12. Improving the Air Mobility Command’s Air Refueler Route Building Capabilities

    Science.gov (United States)

    2014-03-27

    routing tool. Sundar and Rathinam [18] also study a traveling salesman version of the problem in the unmanned aerial vehicle realm. Their focus is on...constrained shortest path with fuel limitations. The objective is to minimize the distance traveled . Some aircraft routing problems involve...radius and network density their only limitations. 4 O’Rourke et al. [15] examine a traveling salesman version of aircraft routing in the unmanned aerial

  13. A Mathematical Model and Algorithm for Routing Air Traffic Under Weather Uncertainty

    Science.gov (United States)

    Sadovsky, Alexander V.

    2016-01-01

    A central challenge in managing today's commercial en route air traffic is the task of routing the aircraft in the presence of adverse weather. Such weather can make regions of the airspace unusable, so all affected flights must be re-routed. Today this task is carried out by conference and negotiation between human air traffic controllers (ATC) responsible for the involved sectors of the airspace. One can argue that, in so doing, ATC try to solve an optimization problem without giving it a precise quantitative formulation. Such a formulation gives the mathematical machinery for constructing and verifying algorithms that are aimed at solving the problem. This paper contributes one such formulation and a corresponding algorithm. The algorithm addresses weather uncertainty and has closed form, which allows transparent analysis of correctness, realism, and computational costs.

  14. Dynamic Air-Route Adjustments - Model,Algorithm,and Sensitivity Analysis

    Institute of Scientific and Technical Information of China (English)

    GENG Rui; CHENG Peng; CUI Deguang

    2009-01-01

    Dynamic airspace management (DAM) is an important approach to extend limited air space resources by using them more efficiently and flexibly.This paper analyzes the use of the dynamic air-route adjustment (DARA) method as a core procedure in DAM systems.DARA method makes dynamic decisions on when and how to adjust the current air-route network with the minimum cost.This model differs from the air traffic flow management (ATFM) problem because it considers dynamic opening and closing of air-route segments instead of only arranging flights on a given air traffic network and it takes into account several new constraints,such as the shortest opening time constraint.The DARA problem is solved using a two-step heuristic algorithm.The sensitivities of important coefficients in the model are analyzed to determine proper values for these coefficients.The computational results based on practical data from the Beijing ATC region show that the two-step heuristic algorithm gives as good results as the CPLEX in less or equal time in most cases.

  15. Airport Activity Statistics of Certificated Route Air Carriers, 1993

    Science.gov (United States)

    1993-12-31

    FIEVNIE 1"M• om XiTrE EEPLAEOTALS (ANPORTHWES TOA...m. .. .. sum795L AMRCA N TRASTTAL.......... -HUB % OF OPLANEMlMl AMO MAIL COLORAD -w• u STEABIDT SPI M...BLUE GRASS ) AIR WISCONSIN ... . . . . . . . . TOTAL . . 38.373 9.72 15.49 2521 MS AS 38.373 9.72 15.49 25.21 A M E R IC A N...ENPLANEMENTS AD MAIL KENTUCKY-Contlnued LEXINGTOWFRANKFORT-Coflinued (BLUE GRASS )-Continued AS 700 AMERUET ................................... TOTAL

  16. Northwest passage: Trade route for large air cushion vehicles

    Science.gov (United States)

    Anderson, J. L.

    1973-01-01

    A conceptual vehicle and powerplant (10,000-ton) nuclear-powered air-cushion vehicle (ACV) that could open the Northwest Passage and other Arctic passages to commercial traffic is identified. The report contains a description of the conceptual vehicle, including the powerplant and operations, an assessment of technical feasibility, estimates of capital and operating costs, and identification of eligible cargo and markets. A comparison of the nuclear ACV freighter with nuclear container ships shows that for containerized or roll-on/roll-off cargo the ACV would provide greatly reduced transit time between North Atlantic and North Pacific ports at a competitive cost.

  17. 77 FR 30437 - Proposed Amendment of Air Traffic Service Routes; Southwestern United States

    Science.gov (United States)

    2012-05-23

    ... Federal Aviation Administration 14 CFR Part 71 RIN 2120-AA66 Proposed Amendment of Air Traffic Service Routes; Southwestern United States AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of... Administration, 800 Independence Avenue SW., Washington, DC 20591; telephone: (202) 267-8783....

  18. Meeting Air Transportation Demand in 2025 by Using Larger Aircraft and Alternative Routing to Complement NextGen Operational Improvements

    Science.gov (United States)

    Smith, Jeremy C.; Guerreiro, Nelson M.; Viken, Jeffrey K.; Dollyhigh, Samuel M.; Fenbert, James W.

    2010-01-01

    A study was performed that investigates the use of larger aircraft and alternative routing to complement the capacity benefits expected from the Next Generation Air Transportation System (NextGen) in 2025. National Airspace System (NAS) delays for the 2025 demand projected by the Transportation Systems Analysis Models (TSAM) were assessed using NASA s Airspace Concept Evaluation System (ACES). The shift in demand from commercial airline to automobile and from one airline route to another was investigated by adding the route delays determined from the ACES simulation to the travel times used in the TSAM and re-generating new flight scenarios. The ACES simulation results from this study determined that NextGen Operational Improvements alone do not provide sufficient airport capacity to meet the projected demand for passenger air travel in 2025 without significant system delays. Using larger aircraft with more seats on high-demand routes and introducing new direct routes, where demand warrants, significantly reduces delays, complementing NextGen improvements. Another significant finding of this study is that the adaptive behavior of passengers to avoid congested airline-routes is an important factor when projecting demand for transportation systems. Passengers will choose an alternative mode of transportation or alternative airline routes to avoid congested routes, thereby reducing delays to acceptable levels for the 2025 scenario; the penalty being that alternative routes and the option to drive increases overall trip time by 0.4% and may be less convenient than the first-choice route.

  19. Risk-Hedged Approach for Re-Routing Air Traffic Under Weather Uncertainty

    Science.gov (United States)

    Sadovsky, Alexander V.; Bilimoria, Karl D.

    2016-01-01

    This presentation corresponds to: our paper explores a new risk-hedged approach for re-routing air traffic around forecast convective weather. In this work, flying through a more likely weather instantiation is considered to pose a higher level of risk. Current operational practice strategically plans re-routes to avoid only the most likely (highest risk) weather instantiation, and then tactically makes any necessary adjustments as the weather evolves. The risk-hedged approach strategically plans re-routes by minimizing the risk-adjusted path length, incorporating multiple possible weather instantiations with associated likelihoods (risks). The resulting model is transparent and is readily analyzed for realism and treated with well-understood shortest-path algorithms. Risk-hedged re-routes are computed for some example weather instantiations. The main result is that in some scenarios, relative to an operational-practice proxy solution, the risk-hedged solution provides the benefits of lower risk as well as shorter path length. In other scenarios, the benefits of the risk-hedged solution are ambiguous, because the solution is characterized by a tradeoff between risk and path length. The risk-hedged solution can be executed in those scenarios where it provides a clear benefit over current operational practice.

  20. Impact of bicycle route type on exposure to traffic-related air pollution.

    Science.gov (United States)

    MacNaughton, Piers; Melly, Steven; Vallarino, Jose; Adamkiewicz, Gary; Spengler, John D

    2014-08-15

    Cyclists are exposed to traffic-related air pollution (TRAP) during their commutes due to their proximity to vehicular traffic. Two of the main components of TRAP are black carbon (BC) and nitrogen dioxide (NO2), which have both been causally associated with increased mortality. To assess the impact of cyclists' exposure to TRAP, a battery-powered mobile monitoring station was designed to sample air pollutants along five bike routes in Boston, Massachusetts. The bike routes were categorized into three types: bike paths, which are separated from vehicle traffic; bike lanes, which are adjacent to traffic; and designated bike lanes, which are shared traffic lanes for buses and cyclists. Bike lanes were found to have significantly higher concentrations of BC and NO2 than bike paths in both adjusted and unadjusted generalized linear models. Higher concentrations were observed in designated bike lanes than bike paths; however, this association was only significant for NO2. After adjusting for traffic density, background concentration, and proximity to intersections, bike lanes were found to have concentrations of BC and NO2 that were approximately 33% higher than bike paths. Distance from the road, vegetation barriers, and reduced intersection density appear to influence these variations. These findings suggest that cyclists can reduce their exposure to TRAP during their commute by using bike paths preferentially over bike lanes regardless of the potential increase of traffic near these routes.

  1. Identifying vital edges in Chinese air route network via memetic algorithm

    Directory of Open Access Journals (Sweden)

    Wenbo Du

    2017-02-01

    Full Text Available Due to rapid development in the past decade, air transportation system has attracted considerable research attention from diverse communities. While most of the previous studies focused on airline networks, here we systematically explore the robustness of the Chinese air route network, and identify the vital edges which form the backbone of Chinese air transportation system. Specifically, we employ a memetic algorithm to minimize the network robustness after removing certain edges, and hence the solution of this model is the set of vital edges. Counterintuitively, our results show that the most vital edges are not necessarily the edges of the highest topological importance, for which we provide an extensive explanation from the microscope view. Our findings also offer new insights to understanding and optimizing other real-world network systems.

  2. Identifying vital edges in Chinese air route network via memetic algorithm

    CERN Document Server

    Du, Wen-Bo; Yan, Gang; Lordan, Oriol; Cao, Xian-Bin

    2016-01-01

    Due to its rapid development in the past decade, air transportation system has attracted considerable research attention from diverse communities. While most of the previous studies focused on airline networks, here we systematically explore the robustness of the Chinese air route network, and identify the vital edges which form the backbone of Chinese air transportation system. Specifically, we employ a memetic algorithm to minimize the network robustness after removing certain edges hence the solution of this model is the set of vital edges. Counterintuitively, our results show that the most vital edges are not necessarily the edges of highest topological importance, for which we provide an extensive explanation from the microscope of view. Our findings also offer new insights to understanding and optimizing other real-world network systems.

  3. Assessment of air quality in and around a steel industry with direct reduction iron route.

    Science.gov (United States)

    Jena, Pradip K; Behera, Dillip K; Mishra, C S K; Mohanty, Saswat K

    2011-10-01

    The coal based Direct Reduced Iron (DRI) route for secondary steel production is now a preferred choice in India. Steel making is invariably associated with emission of air pollutants into the environment. Air quality monitoring was carried out in Winter, Summer and Rainy seasons of 2008 in eight monitoring stations in the work zone and five stations in the residential zone of an Integrated Steel Industry located in Orissa state, India. Four air quality parameters i.e. SPM, RSPM, SO2 and NO2 were monitored. Mean SPM and RSPM values were found to be significantly high (p < 0.01) at stations nearer to source in both work zone and residential zone .The highest average SPM and RSPM values in the work zone recorded were 4869 microg/m3 and 1420 microg/m3 and in the residential zone 294 microg/m3 and 198 microg/m3 respectively. No significant difference in the SO2 and NO2 levels was observed between the work and residential zones. In general, the values of air pollutants were highest in Winter followed by Summer and Rainy season. SPM and RSPM values exceeded the National Air Quality Standards (NAAQS) in both the residential and work zones.

  4. Cerebral air embolism as a complication of computed tomography-guided marking of the lung: depiction of air inflow route from a pulmonary vein to the left atrium.

    Science.gov (United States)

    Higashino, Takanori; Noma, Satoshi; Nishimoto, Yuko; Endo, Junki; Taguchi, Yoshio; Shindo, Toru

    2011-02-01

    Air embolism in the arterial system is a very rare but potentially fatal complication of percutaneous transthoracic needle biopsy or marking. We report a case of a patient with interstitial pneumonia associated with Sjögren syndrome, who presented with systemic arterial air embolism as a complication of computed tomography-guided marking of the lung. The air inflow route was depicted clearly on computed tomography from the peripheral pulmonary vein that crossed the needle pathway to the left atrium.

  5. 78 FR 38236 - Proposed Establishment, Modification and Cancellation of Air Traffic Service (ATS) Routes...

    Science.gov (United States)

    2013-06-26

    ... the affected routes. This action would enhance the safety and efficient management of aircraft within... Airspace Docket No. 13-AEA-3) and be submitted in triplicate to the Docket Management Facility (see...: is a newly established route to become effective August 22, 2013 (78 FR 29615, May 21,...

  6. Radon as a tracer of daily, seasonal and spatial air movements in the Underground Tourist Route "Coal Mine" (SW Poland).

    Science.gov (United States)

    Tchorz-Trzeciakiewicz, Dagmara Eulalia; Parkitny, Tomasz

    2015-11-01

    The surveys of radon concentrations in the Underground Tourist Route "Coal Mine" were carried out using passive and active measurement techniques. Passive methods with application of Solid State Nuclear Track Detectors LR115 were used at 4 points in years 2004-2007 and at 21 points in year 2011. These detectors were exchanged at the beginning of every season in order to get information about seasonal and spatial changes of radon concentrations. The average radon concentration noted in this facility was 799 Bq m(-3) and is consistent with radon concentrations noted in Polish coal mines. Seasonal variations, observed in this underground tourist route, were as follows: the highest radon concentrations were noted during summers, the lowest during winters, during springs and autumns intermediate but higher in spring than in autumn. The main external factor that affected seasonal changes of radon concentrations was the seasonal variation of outside temperature. No correlation between seasonal variations of radon concentrations and seasonal average atmospheric pressures was found. Spatial variations of radon concentrations corresponded with air movements inside the Underground Tourist Route "Coal Mine". The most vivid air movements were noted along the main tunnel in adit and at the place located near no blinded (in the upper part) shaft. Daily variations of radon concentrations were recorded in May 2012 using RadStar RS-230 as the active measurement technique. Typical daily variations of radon concentrations followed the pattern that the highest radon concentrations were recorded from 8-9 a.m. to 7-8 p.m. and the lowest during nights. The main factor responsible for hourly variations of radon concentrations was the daily variation of outside temperatures. No correlations were found between radon concentration and other meteorological parameters such as atmospheric pressure, wind velocity or precipitation. Additionally, the influence of human factor on radon

  7. 78 FR 53239 - Establishment, Modification and Cancellation of Air Traffic Service (ATS) Routes; Northeast...

    Science.gov (United States)

    2013-08-29

    ... navigation guidance for portions of the affected routes. This action enhances the safe and efficient management of aircraft within the National Airspace System. DATES: Effective date 0901 UTC, October 17, 2013... northeast United States (78 FR 38236, June 26, 2013). Interested parties were invited to participate in...

  8. En Route Air Traffic Control Input Devices for the Next Generation

    Science.gov (United States)

    Mainini, Matthew J.

    2010-01-01

    The purpose of this study was to investigate the usefulness of different input device configurations when trial planning new routes for aircraft in an advanced simulation of the en route workstation. The task of trial planning is one of the futuristic tools that is performed by the graphical manipulation of an aircraft's trajectory to reroute the aircraft without voice communication. In this study with two input devices, the FAA's current trackball and a basic optical computer mouse were evaluated with "pick" button in a click-and-hold state and a click-and-release state while the participant dragged the trial plan line. The trial plan was used for three different conflict types: Aircraft Conflicts, Weather Conflicts, and Aircraft + Weather Conflicts. Speed and accuracy were the primary dependent variables. Results indicate that the mouse conditions were significantly faster than the trackball conditions overall with no significant loss of accuracy. Several performance ratings and preference ratings were analyzed from post-run and post-simulation questionnaires. The release conditions were significantly more useful and likable than the hold conditions. The results suggest that the mouse in the release button state was the fastest and most well liked device configuration for trial planning in the en route workstation. Keywords-input devices, en route, controller, workstation, mouse, trackball, NextGen

  9. Value Focused Thinking Analysis of the Pacific Theater’s Future Air Mobility En Route System

    Science.gov (United States)

    2011-06-01

    Number: 609-754-7749 E-mail: peter.axtell@us.af.mil School/Organization: AFIT / ASAM Status: [X] Student [ ] Faculty...PACAF/A4, Mission Brief provided to ASAM class, 16 May 2011. Sere, M. Strategic Airlift En Route Analysis and Considerations to Support the Global

  10. Cyclist route choice, traffic-related air pollution, and lung function: a scripted exposure study

    OpenAIRE

    Jarjour, Sarah; Jerrett, Michael; Westerdahl, Dane; de Nazelle, Audrey; Hanning, Cooper; Daly, Laura; Lipsitt, Jonah; Balmes,John

    2013-01-01

    Abstract Background A travel mode shift to active transportation such as bicycling would help reduce traffic volume and related air pollution emissions as well as promote increased physical activity level. Cyclists, however, are at risk for exposure to vehicle-related air pollutants due to their proximity to vehicle traffic and elevated respiratory rates. To promote safe bicycle commuting, the City of Berkeley, California, has designated a network of ...

  11. Transmission through air as a possible route of exposure for MRSA

    NARCIS (Netherlands)

    Bos, Marian E.H.; Verstappen, Koen M.; Cleef, Van Brigitte A.G.L.; Dohmen, Wietske; Dorado-García, Alejandro; Graveland, Haitske; Duim, Birgitta; Wagenaar, Jaap A.; Kluytmans, Jan A.J.W.; Heederik, Dick J.J.

    2016-01-01

    Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) is highly prevalent in pigs and veal calves. The environment and air in pig and veal calf barns is often contaminated with LA-MRSA, and can act as a transmission source for humans. This study explores exposure-response rel

  12. STS-56 inflight maintenance (IFM) air duct routing on OV-103's middeck

    Science.gov (United States)

    1993-01-01

    STS-56 inflight maintenance (IFM) repair on Discovery's, Orbiter Vehicle (OV) 103's, middeck was required to offset overheating problems with one of the onboard experiments -- Detailed Supplementary Objective (DSO) 322, Human lymphocyte locomotion in microgravity. This 'elephant's trunk' fix was rigged from the airlock's air recirculation duct to DSO 322's forward locker location by Commander Kenneth Cameron. The 'elephant's trunk' was fashioned from trash bags and other plastic items to extend an airline to the troubled area. DSO 322 is collecting data on the locomotion and migration of human lymphocytes through intercellular matrix and is testing the rotating wall vessel and the specimen temperature controller. In the background is the port side wall with the side hatch, middeck accomodations rack (MAR), and shuttle orbiter repackaged galley (SORG) visible.

  13. Relationship between Air Traffic Selection and Training (AT-SAT)) Battery Test Scores and Composite Scores in the Initial en Route Air Traffic Control Qualification Training Course at the Federal Aviation Administration (FAA) Academy

    Science.gov (United States)

    Kelley, Ronald Scott

    2012-01-01

    Scope and Method of Study: This study focused on the development and use of the AT-SAT test battery and the Initial En Route Qualification training course for the selection, training, and evaluation of air traffic controller candidates. The Pearson product moment correlation coefficient was used to measure the linear relationship between the…

  14. 78 FR 78302 - Proposed Modification and Establishment of Air Traffic Service (ATS) Routes in the Vicinity of...

    Science.gov (United States)

    2013-12-26

    ... on this action must submit with those comments a self-addressed, stamped postcard on which the... Meacham Blvd., Fort Worth, TX 76137. Persons interested in being placed on a mailing list for future NPRMs... Federal airways are published in paragraph 6010(a) and low altitude RNAV routes (T) are published...

  15. 通用航空空中游览航线设计研究%Design of General Aviation Air Tour Routes

    Institute of Scientific and Technical Information of China (English)

    覃睿; 李雪娇; 王瑞; 党亚茹

    2015-01-01

    With the rapid development of the general aviation industry,helicopter touring emerges due to its unique advan-tages in viewing range and comfortable experience. During a helicopter air tour,the selection of a travelling route definitely decides the sightseeing effect. Therefore,how to design air tour routes has become a major issue. This article analyzes the factors influencing the design of air tour routes,and gives a more detailed description on how to better design the routes, which will help policy-makers do the planning from a more comprehensive perspective to facilitate the use of helicopters in tourism to further promote the development of both general aviation industry and tourism industry.%随着通用航空业的蓬勃发展,直升飞机游览由于在取景范围和舒适度上有着独到的优点,已成为旅游的较好选择。在利用直升机空中游览时,航线的选择是决定游览效果的关键性决策,如何更好地设计空中游览航线成为空中游览的一项重大问题。分析了空中游览航线设计的影响因素,并就如何设计出更好的航线做了较为详细的说明,有利于决策者从更加全面的角度设计航线,使直升机在旅游业上得到更好的应用,同时合理利用直升飞机游览将有利于通用航空业进一步发展,也将促进旅游业的兴盛。

  16. The influence of automation support on Air Traffic Controller behaviour with a Speed And Route Advisory function

    NARCIS (Netherlands)

    Merwe, K. van de; Oprins, E.A.P.B.; Plaat, A. van der; Erikson, F.

    2009-01-01

    The aim of this paper is to describe the influence of automation support on Air Traffic Controller performance, workload and Situation Awareness (SA). Controllers handle traffic through means of tactical control involving heading, speed and altitude instructions. Future Air Traffic Management (ATM)

  17. Competitive allocation of resources on a network: an agent-based model of air companies competing for the best routes

    CERN Document Server

    Gurtner, Gérald; Lillo, Fabrizio

    2014-01-01

    We present a stylized model of the allocation of resources on a network. By considering as a concrete example the network of sectors of the airspace, where each node is a sector characterized by a maximal number of simultaneously present aircraft, we consider the problem of air companies competing for the allocation of the airspace. Each company is characterized by a cost function, weighting differently punctuality and length of the flight. We consider the model in the presence of pure and mixed populations of types of airline companies and we study how the equilibria depends on the characteristics of the network.

  18. Route churn: an analysis of low-cost carrier route continuity in Europe

    NARCIS (Netherlands)

    de Wit, J.G.; Zuidberg, J.

    2016-01-01

    Discontinuity of air routes is a subject that has been analysed in various ways. For example, the complex network approach focuses on network robustness and resilience due to route interruptions during a relatively short period. Also seasonal interruptions of air routes are a well-documented phenome

  19. 基于机场航线相关的鸟类活动研究%STUDY ON THE RELATION BETWEEN FLY-BIRDS AND AIR ROUTE IN AIRPORT

    Institute of Scientific and Technical Information of China (English)

    孙涛; 赛道建; 吕涛; 卫伟; 邵增珍; 张月侠

    2015-01-01

    本文选择在滑跑阶段活动的鸟类为研究对象,结果显示鸟撞风险的变化程度与鸟类的数量、飞翔轨迹与航线的距离密切相关。根据飞行阶段鸟撞风险评估和人、机、鸟三者间动态的时空位置关系,选择有效措施驱离航线附近活动的鸟类、防止飞鸟侵入机场并向航线靠近,保证飞行航线处于净空状态以防范鸟撞的发生。%This paper analyzed behavior of flying birds in airport during aircraft taxiing.The result shows thatbird strike risk has a relationship with the number and behavior of birds,and the distance between the air route andthe flight birds in the airport.Driving air route efficaciously needs following the evaluation of bird strike risk in flightphase,and dynamic relation in the temporal and spatial position among human,birds,airplane,which can ensurethe flightroute clearance to prevent the bird strike in the flyingroute.

  20. Improving Operational Acceptability of Dynamic Weather Routes Through Analysis of Commonly Use Routings

    Science.gov (United States)

    Evans, Antony D.; Sridhar, Banavar; McNally, David

    2016-01-01

    The Dynamic Weather Routes (DWR) tool is a ground-based trajectory automation system that continuously and automatically analyzes active in-flight aircraft in en route airspace to find simple modifications to flight plan routes that can save significant flying time, while avoiding weather and considering traffic conflicts, airspace sector congestion, special use airspace, and FAA routing restrictions. Trials of the DWR system have shown that significant delay savings are possible. However, some DWR advised routes are also rejected by dispatchers or modified before being accepted. Similarly, of those sent by dispatchers to flight crews as proposed route change requests, many are not accepted by air traffic control, or are modified before implementation as Center route amendments. Such actions suggest that the operational acceptability of DWR advised route corrections could be improved, which may reduce workload and increase delay savings. This paper analyzes the historical usage of different flight routings, varying from simple waypoint pairs to lengthy strings of waypoints incorporating jet routes, in order to improve DWR route acceptability. An approach is developed that can be incorporated into DWR, advising routings with high historical usage and savings potential similar to that of the nominal DWR advisory. It is hypothesized that modifying a nominal DWR routing to one that is commonly used, and nearby, will result in more actual savings since common routings are generally familiar and operationally acceptable to air traffic control. The approach allows routing segments with high historical usage to be concatenated to form routes that meet all DWR constraints. The relevance of a route's historical usage to its acceptance by dispatchers and air traffic control is quantified by analyzing historical DWR data. Results indicate that while historical usage may be less of a concern to flight dispatchers accepting or rejecting DWR advised route corrections, it may be

  1. Security Verification of Secure MANET Routing Protocols

    Science.gov (United States)

    2012-03-22

    the destination. The route discovery phase is complete upon receipt of the RREP at the requesting node. The DYMO protocol is a simpler version of AODV ...described in this appendix. The protocols are Secure AODV (SAODV), Secure Efficient Distance Vector (SEAD), and Secure Link State Routing Protocol (SLSP...SECURITY VERIFICATION OF SECURE MANET ROUTING PROTOCOLS THESIS Matthew F. Steele, Captain, USAF AFIT/GCS/ENG/12-03 DEPARTMENT OF THE AIR FORCE AIR

  2. The Study on the Air Route of Base-jumping Performance%跳伞运动中空中航线的探讨

    Institute of Scientific and Technical Information of China (English)

    冯晓晔

    2012-01-01

    跳伞是高空中勇敢者的运动,是集勇气、意志、智慧和科技于一体的体育项目。跳伞运动在我国有着较长的发展历史,并且是我国竞技体育优势项目之一,特别是定点项目曾多次在世界锦标赛、世界杯和世界航空运动会等大型比赛中取得优异成绩。所谓定点跳伞就是:跳伞员操纵降落伞在指定跳靶内着陆的跳伞。跳伞员操纵降落伞从天而降,能否准确的落在30cm直径的跳靶上,近而多数次均能踩中2cm直径的靶心,除要求要有极高的准确性外,还有诸多的因素如天气状况、心理状况、操纵手法以及降落伞的稳定情况等都起着很大的作用,这中间能否走好空中航线是提高定点成绩的关键。%Skydiving is a game for the brave.It's a sport combining courage,Will,Wisdom,and technology.In China,skydiving has a long developing history and is one of our competitive advantage sports.Particularly for base jumping,We have achieved excellence in many world competitions such as the Parachuting World Championship,Parachuting World Cup etc.Base jumping is a skydiving category in which skydivers manipulate the parachuting umbrella to control the fall and land on the jumping target.This category tests the ability of the skydiver to control the fall and accurately land in the 30 cm diameter jumping target and step on the 2 cm diameter bull's eye as many times as possible.The results are impacted by many factors such as weather,psychology,Control,and the stability of the parachuting umbrella.The key to improving the performance is to take a good air route in the sky.

  3. METODOLOGÍA PARA EVALUAR EL IMPACTO AMBIENTAL SOBRE LA CALIDAD DEL AIRE EN LOS PROYECTOS DE REDISEÑO DE RUTAS DE TRANSPORTE PÚBLICO COLECTIVO EN LAS CIUDADES. ESTUDIO DE CASO: MEDELLÍN METHODOLOGY FOR ASSESSING ENVIRONMENTAL IMPACT ON AIR QUALITY IN PROJECTS REDESIGNING COLLECTIVE PUBLIC TRANSPORT ROUTES IN THE CITIES. CASE STUDY: MEDELLÍN

    Directory of Open Access Journals (Sweden)

    Carlos Echeverri

    2012-06-01

    Full Text Available Este documento establece la metodología y los procedimientos necesarios para evaluar el impacto ambiental sobre la calidad del aire en los proyectos de rediseño de rutas de transporte público colectivo en las principales ciudades del mundo. Para este propósito, se formuló un caso hipotético en la ciudad de Medellín teniendo en cuenta las rutas de transporte público colectivo complementarias al sistema integrado de transporte en el Valle de Aburrá, convirtiendo algunas rutas radiales en rutas transversales o de migración a otras cuencas. Con la reconfiguración propuesta para las rutas de transporte público colectivo la emisión de contaminantes proveniente de los buses no presentó cambios sustanciales. Sin embargo, la concentración de partículas aumentó en ciertos puntos de la zona de estudio y alcanzó valores que superan la norma anual de calidad del aire (50 µg/m³.This document provides the methodology and necessary procedures to assess the environmental impact on air quality in the projects of redesign of collective public transport routes in main cities around the world. For this purpose, it has been formulated a hypothetical case in the city of Medellin keeping in mind the public transport routes that are complementary to the integrated transport system in the Aburrá Valley, transforming some radial routes in transversal routes or migration to other basins. With the reconfiguration proposed for collective public transport routes, pollutant emissions from buses did not show substantial changes. However, the concentration of particles increased at certain points in the study area, reaching values that exceed the annual standard for air quality (50 µg/m³.

  4. FAA Air Traffic Control Operations Concepts. Volume 2. ACF/ACCC (Area Control Facility/Area Control Computer Complex) Terminal and En Route Controllers. Change 1

    Science.gov (United States)

    1988-07-29

    i’MinimumVectorAltitude) * MVA * and {MilitarY’ Route) and (Holding_ PatterrnAirspace) and TOD @2 SLS 3.7.1.2.1.1.1.2 and Fi~nal_Approach_Course and (Navigational-Aid...and{ [Fix]) and(LMinimumVectorAltitude]) * MVA * and( [Military-Route]) and( [HoldingPatternAirspoce]) and .T13D) @ SLS 3.7.1.2.1.1.1.2 Emfphasize...Restore Conflict Alert 370 Pox ,.’Conflict Resolution Adviso, y: The cooobillity shall bc provided to optionally supressresoreo toyhe resolution

  5. Research of Air Route Planning Optimization Method without Threat Based on Improved Ant Colony Algorithm%利用改进蚁群算法的可规避威胁源最优航线规划

    Institute of Scientific and Technical Information of China (English)

    柴毅哲; 杨任农; 马明杰; 刘孟强

    2015-01-01

    Aimed at air route planning problems in complex environment,a route planning optimization method without threat based on the fundamental ant colony algorithm is proposed.The use of this method enhances the descriptive ability of the real flight circumstance to improve the effectiveness of route plan-ning by reconstructing the route planning target function and comprehensively analyzing the information of terrain and threat in aircraft flight environment,including the factors such as route distance,time,fuel, cost and threat evasion ,etc.Still,the use of this method can save algorithm time and enhance efficiency of optimization by improving distance heuristic factor to introduce heuristic direction.The simulation results show that the use of this improved ant colony algorithm can save 10% of the optimization time and reduce 10��odd iterative times compared with that of the fundamental ant colony algorithm.%针对复杂环境中飞行器航线规划问题,在基本蚁群算法的基础上,提出一种可规避威胁源的航线规划方法。通过综合分析飞行器飞行环境中的地形信息和威胁信息,考虑航线距离、时耗、能耗、全程费用和威胁规避等因素,重构航线规划目标函数,加强了对飞行器实际飞行环境的描述,从而提高了航线规划的有效性;通过增加目标节点对下一节点的影响来改进状态转移概率,促使蚂蚁向目标方向前进,以节省计算时间,提高优化效率。仿真结果显示,与基本蚁群算法相比,改进算法可以节省10%的优化时间且缩短10多次迭代次数。

  6. Hurricane Evacuation Routes

    Data.gov (United States)

    Department of Homeland Security — Hurricane Evacuation Routes in the United States A hurricane evacuation route is a designated route used to direct traffic inland in case of a hurricane threat. This...

  7. Lateralization of route continuation and route order

    NARCIS (Netherlands)

    Van Der Ham, Ineke J M; Van Den Hoven, Jacco

    2014-01-01

    Navigation is a complex cognitive ability and its structure is still poorly understood. Memory for route continuation and route order are hypothesized to be at least partially separate components of navigation ability. In the current experiment, participants studied a route in virtual reality. The d

  8. Routing and scheduling problems

    DEFF Research Database (Denmark)

    Reinhardt, Line Blander

    be that the objects routed have an availability time window and a delivery time window or that locations on the path have a service time window. When routing moving transportation objects such as vehicles and vessels schedules are made in connection with the routing. Such schedules represent the time for the presence...... to a destination on a predefined network, the routing and scheduling of vessels in a liner shipping network given a demand forecast to be covered, the routing of manpower and vehicles transporting disabled passengers in an airport and the vehicle routing with time windows where one version studied includes edge...... of a connection between two locations. This could be an urban bus schedule where busses are routed and this routing creates a bus schedule which the passengers between locations use. In this thesis various routing and scheduling problems will be presented. The topics covered will be routing from an origin...

  9. Routing in opportunistic networks

    CERN Document Server

    Dhurandher, Sanjay; Anpalagan, Alagan; Vasilakos, Athanasios

    2013-01-01

    This book provides a comprehensive guide to selected topics, both ongoing and emerging, in routing in OppNets. The book is edited by worldwide technical leaders, prolific researchers and outstanding academics, Dr. Isaac Woungang and co-editors, Dr. Sanjay Kumar Dhurandher, Prof. Alagan Anpalagan and Prof. Athanasios Vasilakos. Consisting of contributions from well known and high profile researchers and scientists in their respective specialties, the main topics that are covered in this book include mobility and routing, social-aware routing, context-based routing, energy-aware routing, incentive-aware routing, stochastic routing, modeling of intermittent connectivity, in both infrastructure and infrastructure-less OppNets. Key Features: Discusses existing and emerging techniques for routing in infrastructure and infrastructure-less OppNets. Provides a unified covering of otherwise disperse selected topics on routing in infrastructure and infrastructure-less OppNets.  Includes a set of PowerPoint slides and g...

  10. Visualizing Internet routing changes.

    Science.gov (United States)

    Lad, Mohit; Massey, Dan; Zhang, Lixia

    2006-01-01

    Today's Internet provides a global data delivery service to millions of end users and routing protocols play a critical role in this service. It is important to be able to identify and diagnose any problems occurring in Internet routing. However, the Internet's sheer size makes this task difficult. One cannot easily extract out the most important or relevant routing information from the large amounts of data collected from multiple routers. To tackle this problem, we have developed Link-Rank, a tool to visualize Internet routing changes at the global scale. Link-Rank weighs links in a topological graph by the number of routes carried over each link and visually captures changes in link weights in the form of a topological graph with adjustable size. Using Link-Rank, network operators can easily observe important routing changes from massive amounts of routing data, discover otherwise unnoticed routing problems, understand the impact of topological events, and infer root causes of observed routing changes.

  11. Hazmat Routes (National)

    Data.gov (United States)

    Department of Transportation — The Federal Motor Carrier Safety Administration (FMCSA) Hazardous Material Routes (NTAD) were developed using the 2004 First Edition TIGER/Line files. The routes are...

  12. Routing on Metacyclic Graphs

    Institute of Scientific and Technical Information of China (English)

    Wenjun Xiao

    2002-01-01

    Wu, Lakshmivarahan and Dhall[5] recently described a deterministic, distributed routing scheme for some special classes of metacyclic graphs. However they have no proof of correctness that the scheme is a shortest path routing algorithm. In the note we give a suboptimal, deterministic routing algorithm.

  13. Routing and scheduling problems

    DEFF Research Database (Denmark)

    Reinhardt, Line Blander

    In today’s globalized society, transport contributes to our daily life in many different ways. The production of the parts for a shelf ready product may take place on several continents and our travel between home and work, vacation travel and business trips has increased in distance the last......, the effectiveness of the network is of importance aiming at satisfying as many costumer demands as possible at a low cost. Routing represent a path between locations such as an origin and destination for the object routed. Sometimes routing has a time dimension as well as the physical paths. This may...... to a destination on a predefined network, the routing and scheduling of vessels in a liner shipping network given a demand forecast to be covered, the routing of manpower and vehicles transporting disabled passengers in an airport and the vehicle routing with time windows where one version studied includes edge...

  14. Route Availabililty Planning Tool -

    Data.gov (United States)

    Department of Transportation — The Route Availability Planning Tool (RAPT) is a weather-assimilated decision support tool (DST) that supports the development and execution of departure management...

  15. Contact Graph Routing

    Science.gov (United States)

    Burleigh, Scott C.

    2011-01-01

    Contact Graph Routing (CGR) is a dynamic routing system that computes routes through a time-varying topology of scheduled communication contacts in a network based on the DTN (Delay-Tolerant Networking) architecture. It is designed to enable dynamic selection of data transmission routes in a space network based on DTN. This dynamic responsiveness in route computation should be significantly more effective and less expensive than static routing, increasing total data return while at the same time reducing mission operations cost and risk. The basic strategy of CGR is to take advantage of the fact that, since flight mission communication operations are planned in detail, the communication routes between any pair of bundle agents in a population of nodes that have all been informed of one another's plans can be inferred from those plans rather than discovered via dialogue (which is impractical over long one-way-light-time space links). Messages that convey this planning information are used to construct contact graphs (time-varying models of network connectivity) from which CGR automatically computes efficient routes for bundles. Automatic route selection increases the flexibility and resilience of the space network, simplifying cross-support and reducing mission management costs. Note that there are no routing tables in Contact Graph Routing. The best route for a bundle destined for a given node may routinely be different from the best route for a different bundle destined for the same node, depending on bundle priority, bundle expiration time, and changes in the current lengths of transmission queues for neighboring nodes; routes must be computed individually for each bundle, from the Bundle Protocol agent's current network connectivity model for the bundle s destination node (the contact graph). Clearly this places a premium on optimizing the implementation of the route computation algorithm. The scalability of CGR to very large networks remains a research topic

  16. The Route Analysis Based On Flight Plan

    Science.gov (United States)

    Feriyanto, Nur; Saleh, Chairul; Fauzi, Achmad; Rachman Dzakiyullah, Nur; Riza Iwaputra, Kahfi

    2016-02-01

    Economic development effects use of air transportation since the business process in every aspect was increased. Many people these days was prefer using airplane because it can save time and money. This situation also effects flight routes, many airlines offer new routes to deal with competition. Managing flight routes is one of the problems that must be faced in order to find the efficient and effective routes. This paper investigates the best routes based on flight performance by determining the amount of block fuel for the Jakarta-Denpasar flight route. Moreover, in this work compares a two kinds of aircraft and tracks by calculating flight distance, flight time and block fuel. The result shows Jakarta-Denpasar in the Track II has effective and efficient block fuel that can be performed by Airbus 320-200 aircraft. This study can contribute to practice in making an effective decision, especially helping executive management of company due to selecting appropriate aircraft and the track in the flight plan based on the block fuel consumption for business operation.

  17. A New Route Maintenance in Dynamic Source Routing Protocol

    CERN Document Server

    Shukla, Ashish

    2010-01-01

    Mobile ad-hoc network (MANET) is infrastructureless, self-organizable, multi hop packet switched network. A number of routing protocols for MANETs have been proposed in recent years. Dynamic Source Routing (DSR) protocol is one of the most popular routing protocol for ad hoc networks. This paper presents a novel method to enhance route maintenance part of DSR protocol. Our proposed route maintenance significantly increases the efficiency of the protocol at the time of route failures.

  18. Improving Reactive Ad Hoc Routing Performance by Geographic Route Length

    Institute of Scientific and Technical Information of China (English)

    CAO Yuan-da; YU Yan-bing; LU Di

    2005-01-01

    In order to help reactive ad hoc routing protocols select better-performance routes, a novel metric named geographic route length (GRL) is proposed. The relationship between GRL metric and routing performance is analyzed in detail. Combined with hop metric, GRL is applied into the original ad hoc on-demand distance vector (AODV) to demonstrate its effectiveness. Simulation experiments have shown that GRL can effectively reduce packet delay and route discovery frequency, thus can improve reactive ad hoc routing performance.

  19. Cumulative Vehicle Routing Problems

    OpenAIRE

    Kara, &#;mdat; Kara, Bahar Yeti&#;; Yeti&#;, M. Kadri

    2008-01-01

    This paper proposes a new objective function and corresponding formulations for the vehicle routing problem. The new cost function defined as the product of the distance of the arc and the flow on that arc. We call a vehicle routing problem with this new objective function as the Cumulative Vehicle Routing Problem (CumVRP). Integer programming formulations with O(n2) binary variables and O(n2) constraints are developed for both collection and delivery cases. We show that the CumVRP is a gener...

  20. IP Routing Protocols

    Science.gov (United States)

    Nolasco Pinto, Armando

    2002-03-01

    Uyless Black is a widely known expert in computer networks and data communications. He is author of more than ten books in the communication technologies field, which puts him in a good position to address this topic. In IP Routing Protocols he starts by providing the background and concepts required for understanding TCP/IP technology. This is done clearly and assumes little prior knowledge of the area. As might be expected, he emphasizes the IP route discovery problem. Later he details several routing protocols.

  1. Class network routing

    Science.gov (United States)

    Bhanot, Gyan; Blumrich, Matthias A.; Chen, Dong; Coteus, Paul W.; Gara, Alan G.; Giampapa, Mark E.; Heidelberger, Philip; Steinmacher-Burow, Burkhard D.; Takken, Todd E.; Vranas, Pavlos M.

    2009-09-08

    Class network routing is implemented in a network such as a computer network comprising a plurality of parallel compute processors at nodes thereof. Class network routing allows a compute processor to broadcast a message to a range (one or more) of other compute processors in the computer network, such as processors in a column or a row. Normally this type of operation requires a separate message to be sent to each processor. With class network routing pursuant to the invention, a single message is sufficient, which generally reduces the total number of messages in the network as well as the latency to do a broadcast. Class network routing is also applied to dense matrix inversion algorithms on distributed memory parallel supercomputers with hardware class function (multicast) capability. This is achieved by exploiting the fact that the communication patterns of dense matrix inversion can be served by hardware class functions, which results in faster execution times.

  2. Routed planar networks

    Directory of Open Access Journals (Sweden)

    David J. Aldous

    2016-04-01

    Full Text Available Modeling a road network as a planar graph seems very natural. However, in studying continuum limits of such networks it is useful to take {\\em routes} rather than {\\em edges} as primitives. This article is intended to introduce the relevant (discrete setting notion of {\\em routed network} to graph theorists. We give a naive classification of all 71 topologically different such networks on 4 leaves, and pose a variety of challenging research questions.

  3. Routing Service Quality—Local Driver Behavior Versus Routing Services

    DEFF Research Database (Denmark)

    Ceikute, Vaida; Jensen, Christian S.

    2013-01-01

    experiments with real vehicle trajectory data and an existing online navigation service. It is found that the availability of information about previous trips enables better prediction of route travel time and makes it possible to provide the users with more popular routes than does a conventional navigation...... of the quality of one kind of location-based service, namely routing services. Specifically, the paper presents a framework that enables the comparison of the routes provided by routing services with the actual driving behaviors of local drivers. Comparisons include route length, travel time, and also route...

  4. Modeling Routing Overhead Generated by Wireless Proactive Routing Protocols

    CERN Document Server

    Javaid, Nadeem; Javaid, Akmal; Malik, Shahzad A

    2011-01-01

    In this paper, we present a detailed framework consisting of modeling of routing overhead generated by three widely used proactive routing protocols; Destination-Sequenced Distance Vector (DSDV), Fish-eye State Routing (FSR) and Optimized Link State Routing (OLSR). The questions like, how these protocols differ from each other on the basis of implementing different routing strategies, how neighbor estimation errors affect broadcast of route requests, how reduction of broadcast overhead achieves bandwidth, how to cope with the problem of mobility and density, etc, are attempted to respond. In all of the above mentioned situations, routing overhead and delay generated by the chosen protocols can exactly be calculated from our modeled equations. Finally, we analyze the performance of selected routing protocols using our proposed framework in NS-2 by considering different performance parameters; Route REQuest (RREQ) packet generation, End-to-End Delay (E2ED) and Normalized Routing Load (NRL) with respect to varyi...

  5. Modeling Routing Overhead Generated by Wireless Reactive Routing Protocols

    CERN Document Server

    Javaid, Nadeem; Javaid, Akmal; Malik, Shahzad A

    2011-01-01

    In this paper, we have modeled the routing over- head generated by three reactive routing protocols; Ad-hoc On-demand Distance Vector (AODV), Dynamic Source Routing (DSR) and DYnamic MANET On-deman (DYMO). Routing performed by reactive protocols consists of two phases; route discovery and route maintenance. Total cost paid by a protocol for efficient routing is sum of the cost paid in the form of energy consumed and time spent. These protocols majorly focus on the optimization performed by expanding ring search algorithm to control the flooding generated by the mechanism of blind flooding. So, we have modeled the energy consumed and time spent per packet both for route discovery and route maintenance. The proposed framework is evaluated in NS-2 to compare performance of the chosen routing protocols.

  6. Location-routing problems

    Energy Technology Data Exchange (ETDEWEB)

    Laporte, G.

    1987-01-01

    Location-routing problems involve simultaneously locating a number of facilities among candidate sites and establishing delivery routes to a set of users in such a way that the total system cost is minimized. This paper presents a survey of such problems. It includes some applications and examples of location-routing problems, a description of the main heuristics that have been developed for such problems, and reviews of various formulations and algorithms used in solving these problems. A more detailed review is given of exact algorithms for the vehicle routing problem, three-index vehicle flow formulations, and two-index vehicle flow formulations and algorithms for symmetrical and non-symmetrical problems. It is concluded that location-routing problem research is a fast-growing area, with most developments occurring over the past few years; however, research is relatively fragmented, often addresses problems which are too specific and contains several voids which have yet to be filled. A number of promising research areas are identified. 137 refs., 3 figs.

  7. Multihop Wireless Networks Opportunistic Routing

    CERN Document Server

    Zeng, Kai; Li, Ming

    2011-01-01

    This book provides an introduction to opportunistic routing an emerging technology designed to improve the packet forwarding reliability, network capacity and energy efficiency of multihop wireless networks This book presents a comprehensive background to the technological challenges lying behind opportunistic routing. The authors cover many fundamental research issues for this new concept, including the basic principles, performance limit and performance improvement of opportunistic routing compared to traditional routing, energy efficiency and distributed opportunistic routing protocol desig

  8. Collective network routing

    Science.gov (United States)

    Hoenicke, Dirk

    2014-12-02

    Disclosed are a unified method and apparatus to classify, route, and process injected data packets into a network so as to belong to a plurality of logical networks, each implementing a specific flow of data on top of a common physical network. The method allows to locally identify collectives of packets for local processing, such as the computation of the sum, difference, maximum, minimum, or other logical operations among the identified packet collective. Packets are injected together with a class-attribute and an opcode attribute. Network routers, employing the described method, use the packet attributes to look-up the class-specific route information from a local route table, which contains the local incoming and outgoing directions as part of the specifically implemented global data flow of the particular virtual network.

  9. Optimizing well intervention routes

    Energy Technology Data Exchange (ETDEWEB)

    Paiva, Ronaldo O. [PETROBRAS S.A., Vitoria, ES (Brazil); Schiozer, Denis J.; Bordalo, Sergio N. [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica. Centro de Estudo do Petroleo (CEPETRO)]. E-mail: denis@dep.fem.unicamp.br; bordalo@dep.fem.unicamp.br

    2000-07-01

    This work presents a method for optimizing the itinerary of work over rigs, i.e., the search for the route of minimum total cost, and demonstrates the importance of the dynamics of reservoir behaviour. The total cost of a route includes the rig expenses (transport, assembly and operation), which are functions of time and distances, plus the losses of revenue in wells waiting for the rig, which are also dependent of time. A reservoir simulator is used to evaluate the monetary influence of the well shutdown on the present value of the production curve. Finally, search algorithms are employed to determine the route of minimal cost. The Simulated Annealing algorithm was also successful in optimizing the distribution of a list of wells among different work over rigs. The rational approach presented here is recommended for management teams as a standard procedure to define the priority of wells scheduled for work over. (author)

  10. Occurrence of radon in the Polish underground tourist routes

    Directory of Open Access Journals (Sweden)

    Jerzy Olszewski

    2015-08-01

    Full Text Available Background: There are about 200 underground tourist routes in Poland. There are caves, mines or underground structures. This paper presents the results of the research intended to identify the extent of the occurrence of radon concentrations in underground areas of tourist routes. Material and Methods: We conducted the measurement of periodic concentrations of radon (1–2 months in the summer using type Tastrak trace detectors. We determined the average concentrations of radon in air in 66 underground tourist routes in Poland. Results: The research results comprise 259 determinations of average radon concentrations in 66 routes. The arithmetic average of the results was 1610 Bqm–3, and the maximum measured concentration was over 20 000 Bqm–3. The minimum concentration was 100 Bqm–3 (threshold method considering the arithmetic average of the measurements. It was found that in 67% of the routes, the average concentration of radon has exceeded 300 Bqm–3 and in 22 underground routes it exceeded 1000 Bqm–3. Conclusions: Radon which occurs in many Polish underground tourist routes may be an organizational, legal and health problem. It is necessary to develop a program of measures to reduce radon concentrations in underground routes, especially routes located in the former mines. Med Pr 2015;66(4:557–563

  11. Flying Ad-Hoc Networks: Routing Protocols, Mobility Models, Issues

    OpenAIRE

    Muneer Bani Yassein; “Nour Alhuda” Damer

    2016-01-01

    Flying Ad-Hoc Networks (FANETs) is a group of Unmanned Air Vehicles (UAVs) which completed their work without human intervention. There are some problems in this kind of networks: the first one is the communication between (UAVs). Various routing protocols introduced classified into three categories, static, proactive, reactive routing protocols in order to solve this problem. The second problem is the network design, which depends on the network mobility, in which is the process of cooperati...

  12. SET-Routes programme

    CERN Multimedia

    Marietta Schupp, EMBL Photolab

    2008-01-01

    Dr Sabine Hentze, specialist in human genetics, giving an Insight Lecture entitled "Human Genetics – Diagnostics, Indications and Ethical Issues" on 23 September 2008 at EMBL Heidelberg. Activities in a achool in Budapest during a visit of Angela Bekesi, Ambassadors for the SET-Routes programme.

  13. Whirlpool routing for mobility

    KAUST Repository

    Lee, Jung Woo

    2010-01-01

    We present the Whirlpool Routing Protocol (WARP), which efficiently routes data to a node moving within a static mesh. The key insight in WARP\\'s design is that data traffic can use an existing routing gradient to efficiently probe the topology, repair the routing gradient, and communicate these repairs to nearby nodes. Using simulation, controlled testbeds, and real mobility experiments, we find that using the data plane for topology maintenance is highly effective due to the incremental nature of mobility updates. WARP leverages the fact that converging flows at a destination make the destination have the region of highest traffic. We provide a theoretical basis for WARP\\'s behavior, defining an "update area" in which the topology must adjust when a destination moves. As long as packets arrive at a destination before it moves outside of the update area, WARP can repair the topology using the data plane. Compared to existing protocols, such as DYMO and HYPER, WARP\\'s packet drop rate is up to 90% lower while sending up to 90% fewer packets.

  14. SET-Routes programme

    CERN Multimedia

    CERN audiovisual service

    2009-01-01

    The SET-Routes programme, launched in 2007 with the goal of attracting girls and young women to careers in science, came to an end in April this year. The result of a collaboration between EMBL, EMBO and CERN, the programme established a network of "ambassadors", women scientists who went out to talk about their careers in science at schools and universities across Europe.

  15. Vehicle Routing Problem Models

    Directory of Open Access Journals (Sweden)

    Tonči Carić

    2004-01-01

    Full Text Available The Vehicle Routing Problem cannot always be solved exactly,so that in actual application this problem is solved heuristically.The work describes the concept of several concrete VRPmodels with simplified initial conditions (all vehicles are ofequal capacity and start from a single warehouse, suitable tosolve problems in cases with up to 50 users.

  16. 76 FR 5068 - Establishment of Low Altitude Area Navigation Routes (T-281, T-283, T-285, T-286, and T-288...

    Science.gov (United States)

    2011-01-28

    ... Routes (T-281, T- 283, T-285, T-286, and T-288); Nebraska and South Dakota AGENCY: Federal Aviation... (RNAV) routes, designated T-281, T-283, T-285, T-286, and T-288, over Nebraska and South Dakota; controlled by Denver Air Route Traffic Control Center (ARTCC) and Minneapolis ARTCC. T-routes are...

  17. Air traffic management evaluation tool

    Science.gov (United States)

    Sridhar, Banavar (Inventor); Sheth, Kapil S. (Inventor); Chatterji, Gano Broto (Inventor); Bilimoria, Karl D. (Inventor); Grabbe, Shon (Inventor); Schipper, John F. (Inventor)

    2012-01-01

    Methods for evaluating and implementing air traffic management tools and approaches for managing and avoiding an air traffic incident before the incident occurs. A first system receives parameters for flight plan configurations (e.g., initial fuel carried, flight route, flight route segments followed, flight altitude for a given flight route segment, aircraft velocity for each flight route segment, flight route ascent rate, flight route descent route, flight departure site, flight departure time, flight arrival time, flight destination site and/or alternate flight destination site), flight plan schedule, expected weather along each flight route segment, aircraft specifics, airspace (altitude) bounds for each flight route segment, navigational aids available. The invention provides flight plan routing and direct routing or wind optimal routing, using great circle navigation and spherical Earth geometry. The invention provides for aircraft dynamics effects, such as wind effects at each altitude, altitude changes, airspeed changes and aircraft turns to provide predictions of aircraft trajectory (and, optionally, aircraft fuel use). A second system provides several aviation applications using the first system. Several classes of potential incidents are analyzed and averted, by appropriate change en route of one or more parameters in the flight plan configuration, as provided by a conflict detection and resolution module and/or traffic flow management modules. These applications include conflict detection and resolution, miles-in trail or minutes-in-trail aircraft separation, flight arrival management, flight re-routing, weather prediction and analysis and interpolation of weather variables based upon sparse measurements. The invention combines these features to provide an aircraft monitoring system and an aircraft user system that interact and negotiate changes with each other.

  18. Route Repetition and Route Retracing: Effects of Cognitive Aging

    Directory of Open Access Journals (Sweden)

    Jan Malte Wiener

    2012-05-01

    Full Text Available Retracing a recently traveled route is a frequent navigation task when learning novel routes or exploring unfamiliar environments. In the present study we utilized virtual environments technology to investigate age-related differences in repeating and retracing a learned route. In the training phase of the experiment participants were guided along a route consisting of multiple intersections each featuring one unique landmark. In the subsequent test phase, they were guided along short sections of the route and asked to indicate overall travel direction (repetition or retracing, the direction required to continue along the route, and the next landmark they would encounter. Results demonstrate age-related deficits in all three tasks. More specifically, in contrast to younger participants, the older participants had greater problems during route retracing than during route repetition. While route repetition can be solved with egocentric response or route strategies, successfully retracing a route requires allocentric processing. The age-related deficits in route retracing are discussed in the context of impaired allocentric processing and shifts from allocentric to egocentric navigation strategies as a consequence of age-related hippocampal degeneration.

  19. Automated Flight Routing Using Stochastic Dynamic Programming

    Science.gov (United States)

    Ng, Hok K.; Morando, Alex; Grabbe, Shon

    2010-01-01

    Airspace capacity reduction due to convective weather impedes air traffic flows and causes traffic congestion. This study presents an algorithm that reroutes flights in the presence of winds, enroute convective weather, and congested airspace based on stochastic dynamic programming. A stochastic disturbance model incorporates into the reroute design process the capacity uncertainty. A trajectory-based airspace demand model is employed for calculating current and future airspace demand. The optimal routes minimize the total expected traveling time, weather incursion, and induced congestion costs. They are compared to weather-avoidance routes calculated using deterministic dynamic programming. The stochastic reroutes have smaller deviation probability than the deterministic counterpart when both reroutes have similar total flight distance. The stochastic rerouting algorithm takes into account all convective weather fields with all severity levels while the deterministic algorithm only accounts for convective weather systems exceeding a specified level of severity. When the stochastic reroutes are compared to the actual flight routes, they have similar total flight time, and both have about 1% of travel time crossing congested enroute sectors on average. The actual flight routes induce slightly less traffic congestion than the stochastic reroutes but intercept more severe convective weather.

  20. Operational Evaluatioin of Dynamic Weather Routes at American Airlines

    Science.gov (United States)

    McNally, David; Sheth, Kapil; Gong, Chester; Borchers, Paul; Osborne, Jeff; Keany, Desmond; Scott, Brennan; Smith, Steve; Sahlman, Scott; Lee, Chuhan; Cheng, Jinn-Hwei

    2013-01-01

    Dynamic Weather Routes (DWR) is a search engine that continuously and automatically analyzes inflight aircraft in en route airspace and proposes simple route amendments for more efficient routes around convective weather while considering sector congestion, traffic conflicts, and active Special Use Airspace. NASA and American Airlines (AA) are conducting an operational trial of DWR at the AA System Operations Center in Fort Worth, TX. The trial includes only AA flights in Fort Worth Center airspace. Over the period from July 31, 2012 through August 31, 2012, 45% of routes proposed by DWR and evaluated by AA users - air traffic control coordinators and flight dispatchers - were rated as acceptable as proposed or with some modifications. The wind-corrected potential flying time savings for these acceptable routes totals 470 flying min, and results suggest another 1,500 min of potential savings for flights not evaluated due to staffing limitations. A sector congestion analysis shows that in only two out of 83 DWR routes rated acceptable by AA staff were the flights predicted to fly through a congested sector inside of 30 min downstream of present position. This shows that users considered sector congestion data provided by DWR automation and in nearly all cases did not accept routes through over-capacity sectors. It is estimated that 12 AA flights were given reroute clearances as a direct result of DWR for a total savings of 67 flying min.

  1. Increasingly minimal bias routing

    Energy Technology Data Exchange (ETDEWEB)

    Bataineh, Abdulla; Court, Thomas; Roweth, Duncan

    2017-02-21

    A system and algorithm configured to generate diversity at the traffic source so that packets are uniformly distributed over all of the available paths, but to increase the likelihood of taking a minimal path with each hop the packet takes. This is achieved by configuring routing biases so as to prefer non-minimal paths at the injection point, but increasingly prefer minimal paths as the packet proceeds, referred to herein as Increasing Minimal Bias (IMB).

  2. Electronic route information panels (DRIPs).

    NARCIS (Netherlands)

    2008-01-01

    Also in the Netherlands, the term Dynamic Route Information Panel (DRIP) is used for an electronic route information panel. A DRIP usually indicates whether there are queues on the various routes to a particular destination and how long they are. On certain locations DRIPS also give the estimated tr

  3. Stochastic vehicle routing with recourse

    DEFF Research Database (Denmark)

    Gørtz, Inge Li; Nagarajan, Viswanath; Saket, Rishi

    2012-01-01

    We study the classic Vehicle Routing Problem in the setting of stochastic optimization with recourse. StochVRP is a two-stage problem, where demand is satisfied using two routes: fixed and recourse. The fixed route is computed using only a demand distribution. Then after observing the demand...... instantiations, a recourse route is computed - but costs here become more expensive by a factor λ. We present an O(log2n ·log(nλ))-approximation algorithm for this stochastic routing problem, under arbitrary distributions. The main idea in this result is relating StochVRP to a special case of submodular...

  4. Robustness of airline route networks

    Science.gov (United States)

    Lordan, Oriol; Sallan, Jose M.; Escorihuela, Nuria; Gonzalez-Prieto, David

    2016-03-01

    Airlines shape their route network by defining their routes through supply and demand considerations, paying little attention to network performance indicators, such as network robustness. However, the collapse of an airline network can produce high financial costs for the airline and all its geographical area of influence. The aim of this study is to analyze the topology and robustness of the network route of airlines following Low Cost Carriers (LCCs) and Full Service Carriers (FSCs) business models. Results show that FSC hubs are more central than LCC bases in their route network. As a result, LCC route networks are more robust than FSC networks.

  5. Personal continuous route pattern mining

    Institute of Scientific and Technical Information of China (English)

    Qian YE; Ling CHEN; Gen-cai CHEN

    2009-01-01

    In the daily life, people often repeat regular routes in certain periods. In this paper, a mining system is developed to find the continuous route patterns of personal past trips. In order to count the diversity of personal moving status, the mining system employs the adaptive GPS data recording and five data filters to guarantee the clean trips data. The mining system uses a client/server architecture to protect personal privacy and to reduce the computational load. The server conducts the main mining procedure but with insufficient information to recover real personal routes. In order to improve the scalability of sequential pattern mining, a novel pattern mining algorithm, continuous route pattern mining (CRPM), is proposed. This algorithm can tolerate the different disturbances in real routes and extract the frequent patterns. Experimental results based on nine persons' trips show that CRPM can extract more than two times longer route patterns than the traditional route pattern mining algorithms.

  6. Route Monopolie and Optimal Nonlinear Pricing

    Science.gov (United States)

    Tournut, Jacques

    2003-01-01

    To cope with air traffic growth and congested airports, two solutions are apparent on the supply side: 1) use larger aircraft in the hub and spoke system; or 2) develop new routes through secondary airports. An enlarged route system through secondary airports may increase the proportion of route monopolies in the air transport market.The monopoly optimal non linear pricing policy is well known in the case of one dimension (one instrument, one characteristic) but not in the case of several dimensions. This paper explores the robustness of the one dimensional screening model with respect to increasing the number of instruments and the number of characteristics. The objective of this paper is then to link and fill the gap in both literatures. One of the merits of the screening model has been to show that a great varieD" of economic questions (non linear pricing, product line choice, auction design, income taxation, regulation...) could be handled within the same framework.VCe study a case of non linear pricing (2 instruments (2 routes on which the airline pro_ddes customers with services), 2 characteristics (demand of services on these routes) and two values per characteristic (low and high demand of services on these routes)) and we show that none of the conclusions of the one dimensional analysis remain valid. In particular, upward incentive compatibility constraint may be binding at the optimum. As a consequence, they may be distortion at the top of the distribution. In addition to this, we show that the optimal solution often requires a kind of form of bundling, we explain explicitly distortions and show that it is sometimes optimal for the monopolist to only produce one good (instead of two) or to exclude some buyers from the market. Actually, this means that the monopolist cannot fully apply his monopoly power and is better off selling both goods independently.We then define all the possible solutions in the case of a quadratic cost function for a uniform

  7. Instability Free Routing: Beyond One Protocol Instance

    Science.gov (United States)

    2008-12-01

    assigned a Rout- ing Information Base (RIB) [13]. This database is used to store the routing information related to the routing process (e.g., routes...presents routing anomalies that can derive from route selection by itself, i.e., without any route redis - tribution configured between the routing... redis - tributed into the RIP protocol, all RIP messages received from the neighbors are in fact discarded independently of the AD values. This

  8. New Routing Metrics for ADHOC Network Routing Protocols

    Science.gov (United States)

    Reddy, P. C.

    2014-12-01

    The performance and reliability of Internet is measured using different quantities. When the quantities measured are essential and have wide range of acceptance then they are called metrics. Performance metrics enable comparison and selection among the alternatives. In computer networks, metrics are used to evaluate an application, protocol etc. Routing in adhoc networks is nontrivial. Routing protocols for adhoc networks are still evolving and there is need for continuous evaluation of them. In the literature existing, several routing protocols are evaluated using standard metrics under different conditions. This paper proposes new metrics for evaluation of routing protocols and uses them to evaluate the adhoc network routing protocols AODV, DSR, DSDV and TORA. Simulation environment is created using NS-2 simulator. Typical range of speeds, pause times and data rates are used. The results provide new insights in to the working of the routing protocols.

  9. Combining Speed and Routing Decisions in Maritime Transportation

    DEFF Research Database (Denmark)

    Kontovas, Christos A.; Psaraftis, Harilaos N.; Wen, Min

    We present recent results on the problem of combining ship speed and routing decisions. Speed is a key determinant of the economic and the environmental performance affecting variables such as trip duration, fuel costs, and air emissions, among others. It is seen that inputs such as fuel cost, sh...

  10. Degree 3 Networks Topological Routing

    DEFF Research Database (Denmark)

    Gutierrez Lopez, Jose Manuel; Riaz, M. Tahir; Pedersen, Jens Myrup;

    2009-01-01

    Topological routing is a table free alternative to traditional routing methods. It is specially well suited for organized network interconnection schemes. Topological routing algorithms correspond to the type O(1), constant complexity, being very attractive for large scale networks. It has been...... proposed for many topologies and this work compares the algorithms for three degree three topologies using a more analytical approach than previous studies....

  11. A Primer of Multicast Routing

    CERN Document Server

    Rosenberg, Eric

    2012-01-01

    Whereas unicast routing determines a path from one source node to one destination node, multicast routing determines a path from one source to many destinations, or from many sources to many destinations. We survey multicast routing methods for when the set of destinations is static, and for when it is dynamic. While most of the methods we review are tree based, some non-tree methods are also discussed. We survey results on the shape of multicast trees, delay constrained multicast routing, aggregation of multicast traffic, inter-domain multicast, and multicast virtual private networks. We focu

  12. Alternative routes of insulin delivery.

    Science.gov (United States)

    Krishnankutty, Ranjith K; Mathew, Aju; Sedimbi, Saikiran K; Suryanarayan, Shrikumar; Sanjeevi, Carani B

    2009-10-01

    Parenteral route of insulin administration has been the mode of treatment for all Type 1 diabetics and Type 2 diabetics with complications. Patient compliance has really been a major concern for this route of administration. Several alternative routes of administration are under consideration for effective glycemic control, including oral, inhaled, buccal, nasal, and patch routes. One of the approaches involving inhaled insulin has now reached the market. Several other candidates may reach the market in the near future, the promising one being oral insulin.

  13. Alternative routes of insulin delivery

    Institute of Scientific and Technical Information of China (English)

    Ranjith K. Krishnankutty; Aju Mathew; Saikiran K. Sedimbi; Shrikumar Suryanarayan; Carani B. Sanjeevi

    2009-01-01

    Parenteral route of insulin administration has been the mode of treatment for all Type 1 diabetics and Type 2 diabetics with complications. Patient compliance has really been a major concern for this route of administration. Several alternative routes of administration are under consideration for effective glycemic control, including oral, inhaled, buccal, nasal, and patch routes. One of the approaches involving inhaled insulin has now reached the market. Several other candidates may reach the market in the near future, the promising one being oral insulin.

  14. Route Elimination Heuristic for Vehicle Routing Problem with Time Windows

    Directory of Open Access Journals (Sweden)

    Sándor Csiszár

    2005-11-01

    Full Text Available The paper deals with the design of a route elimination (RE algorithm for thevehicle routing problem with time windows (VRPTW. The problem has two objectives, oneof them is the minimal number of routes the other is the minimal cost. To cope with theseobjectives effectively two-phase solutions are often suggested in the relevant literature. Inthe first phase the main focus is the route elimination, in the second one it is the costreduction. The algorithm described here is a part of a complete VRPWT study. The methodwas developed by studying the graph behaviour during the route elimination. For thispurpose a model -called “Magic Bricks” was developed. The computation results on theSolomon problem set show that the developed algorithm is competitive with the best ones.

  15. Hardware Routing Lookup with SDRAMT

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The authors present a routing lookup architecture, SDIR(SDRAM based Direct Index Routing). With pipeline and interleaving access technique, SDIR can provide scalable lookup speed from 16.7 MPPS(megapacket per second) to 133 MPPS with SDRAM running at 133MHz frequency.

  16. Perception bias in route choice

    NARCIS (Netherlands)

    Vreeswijk, J.D.; Thomas, T.; Berkum, van E.C.; Arem, van B.

    2014-01-01

    Travel time is probably one of the most studied attributes in route choice. Recently, perception of travel time received more attention as several studies have shown its importance in explaining route choice behavior. In particular, travel time estimates by travelers appear to be biased against non-

  17. An enzymatic route to selenazolines.

    Science.gov (United States)

    Koehnke, Jesko; Morawitz, Falk; Bent, Andrew F; Houssen, Wael E; Shirran, Sally L; Fuszard, Matthew A; Smellie, Iain A; Botting, Catherine H; Smith, Margaret C M; Jaspars, Marcel; Naismith, James H

    2013-03-18

    Ringing the changes: Selenazolines have applications in medicinal chemistry, but their synthesis is challenging. We report a new convenient and less toxic route to these heterocycles that starts from commercially available selenocysteine. The new route depends on a heterocyclase enzyme that creates oxazolines and thiazolines from serines/threonines and cysteines.

  18. Route-external and route-internal landmarks in route descriptions : Effects of route length and map design

    NARCIS (Netherlands)

    Westerbeek, Hans; Maes, Alfons

    2013-01-01

    Landmarks are basic ingredients in route descriptions. They often mark choice points: locations where travellers choose from different options how to continue the route. This study focuses on one of the loose ends in the taxonomy of landmarks. In a memory-based production experiment in which respond

  19. Stochastic Vehicle Routing with Recourse

    CERN Document Server

    Goertz, Inge Li; Saket, Rishi

    2012-01-01

    We study the classic Vehicle Routing Problem in the setting of stochastic optimization with recourse. StochVRP is a two-stage optimization problem, where demand is satisfied using two routes: fixed and recourse. The fixed route is computed using only a demand distribution. Then after observing the demand instantiations, a recourse route is computed -- but costs here become more expensive by a factor lambda. We present an O(log^2 n log(n lambda))-approximation algorithm for this stochastic routing problem, under arbitrary distributions. The main idea in this result is relating StochVRP to a special case of submodular orienteering, called knapsack rank-function orienteering. We also give a better approximation ratio for knapsack rank-function orienteering than what follows from prior work. Finally, we provide a Unique Games Conjecture based omega(1) hardness of approximation for StochVRP, even on star-like metrics on which our algorithm achieves a logarithmic approximation.

  20. Road Routes for Waste Disposal - MDC_RecyclingRoute

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This CURBSIDE RECYCLING ROUTES BOUNDARIES LAYER IS A polygon feature class created for the Miami-Dade Department of Solid Waste Management (DSWM). It contains the...

  1. Port Authority of Allegheny County Transit Routes

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Shapefile of Transit Routes - Please refer to each resource for active dates of the route information. Routes change over time,

  2. Pheromone based alternative route planning

    Directory of Open Access Journals (Sweden)

    Liangbing Feng

    2016-08-01

    Full Text Available In this work, we propose an improved alternative route calculation based on alternative figures, which is suitable for practical environments. The improvement is based on the fact that the main traffic route is the road network skeleton in a city. Our approach using nodes may generate a higher possibility of overlapping. We employ a bidirectional Dijkstra algorithm to search the route. To measure the quality of an Alternative Figures (AG, three quotas are proposed. The experiment results indicate that the improved algorithm proposed in this paper is more effective than others.

  3. Millimeter Wave Alternate Route Study.

    Science.gov (United States)

    1981-04-01

    A0-AI02 303 HARRIS CORP MELBOURNE FL GOVERNMENT COMMUNICATION ST--ETC FIG 17/2.1 MILLIMETER WAVE ALENT ROUTE STUDT.(U) APR W C ADAMS J J PAN, W C...481-487. 4-7 abm ADAOO0 303 HARRIS CORP MELBOURNE FL GOVERNMENT COMMUNICATION S -ETC F/G 17/2.1 MILLIMETER WAVE ALTERNATE ROUTE STUDY.(U) APR 81 W C...7-21L’j r AD-A102 303 HARRIS CORP MELBOURNE FL GOVERNMENT COMMUNICATION ST--ETC F/A 17/2.1 MILLIMETER WAVE ALTERNATE ROUTE STUDY(U) APR 81 W C ADAMS

  4. Electric Vehicle Green Routing with Possible En-Route Recharging

    OpenAIRE

    BAOUCHE, Fouad; BILLOT, Romain; Trigui, Rochdi; EL FAOUZI, Nour Eddin

    2014-01-01

    The deployment of Electric Vehicles (EVs) is constrained mainly by the restricted autonomy, the lack of charging stations, the battery recharge time and recuperation capability (e.g. braking phases or downhill). In this study we aim to develop a green routing tool to encourage the use of EV. To overcome the autonomy limitation we propose a methodology for the EV that includes a charging stations location model, an energy graph construction for EV routing and a resolution scheme for the routin...

  5. 75 FR 47252 - Proposed Establishment of Low Altitude Area Navigation Routes (T-281, T-283, T-285, T-286, and T...

    Science.gov (United States)

    2010-08-05

    ... Altitude Area Navigation Routes (T- 281, T-283, T-285, T-286, and T-288); Nebraska and South Dakota AGENCY... action proposes to establish five low altitude Area Navigation (RNAV) routes, designated T-281, T-283, T-285, T-286, and T- 288, over Nebraska and South Dakota; controlled by Denver Air Route Traffic...

  6. 基于元胞蚂蚁算法的防空靶机航路规划研究%Route Planning of Anti-Air Target Drone Based on Cellular-Ant Colony Algorithm

    Institute of Scientific and Technical Information of China (English)

    刘志强; 雷宇曜; 阳再清

    2014-01-01

    防空靶机飞行航路设计是实现靶机有效控制,确保高效完成供靶任务的保障。通过对靶机三维航路规划模型进行分析,给出了元胞蚂蚁算法的航路规划模型的求解方法及算法实现的具体流程,并分别应用蚁群算法和元胞蚂蚁算法进行仿真实验。结果表明:元胞蚂蚁算法克服了蚁群算法收敛速度慢、陷于局部最小值的缺陷,可得到较优的航路。%The design of the flight airway of anti-air target is essential to the effective target control and the high effective completion of target supply task. Through the analysis of the three-dimensional airway design model, the solution method and corresponding algorithm flow of the cellular-ant colony algorithm is provided in this paper. The simulation experiment of the ant colony and cellular-ant colony algorithms is carried out, which shows that the cellular ant algorithm over comes the ant colony algorithm disadvantages of the slow convergence and local optima, and it is able to obtain optimal airway.

  7. Reverse flood routing with the inverted Muskingum storage routing scheme

    Directory of Open Access Journals (Sweden)

    A. D. Koussis

    2012-01-01

    Full Text Available This work treats reverse flood routing aiming at signal identification: inflows are inferred from observed outflows by orienting the Muskingum scheme against the wave propagation direction. Routing against the wave propagation is an ill-posed, inverse problem (small errors amplify, leading to large spurious responses; therefore, the reverse solution must be smoothness-constrained towards stability and uniqueness (regularised. Theoretical constrains on the coefficients of the reverse routing scheme assist in error control, but optimal grids are derived by numerical experimentation. Exact solutions of the convection-diffusion equation, for a single and a composite wave, are reverse-routed and in both instances the wave is backtracked well for a range of grid parameters. In the arduous test of a square pulse, the result is comparable to those of more complex methods. Seeding outflow data with random errors enhances instability; to cope with the spurious oscillations, the reversed solution is conditioned by smoothing via low-pass filtering or optimisation. Good-quality inflow hydrographs are recovered with either smoothing treatment, yet the computationally demanding optimisation is superior. Finally, the reverse Muskingum routing method is compared to a reverse-solution method of the St. Venant equations of flood wave motion and is found to perform equally well, at a fraction of the computing effort. This study leads us to conclude that the efficiently attained good inflow identification rests on the simplicity of the Muskingum reverse routing scheme that endows it with numerical robustness.

  8. Topological Routing in Large-Scale Networks

    DEFF Research Database (Denmark)

    Pedersen, Jens Myrup; Knudsen, Thomas Phillip; Madsen, Ole Brun

    2004-01-01

    A new routing scheme, Topological Routing, for large-scale networks is proposed. It allows for efficient routing without large routing tables as known from traditional routing schemes. It presupposes a certain level of order in the networks, known from Structural QoS. The main issues in applying...... Topological Routing to large-scale networks are discussed. Hierarchical extensions are presented along with schemes for shortest path routing, fault handling and path restoration. Further reserach in the area is discussed and perspectives on the prerequisites for practical deployment of Topological Routing...

  9. Topological Routing in Large-Scale Networks

    DEFF Research Database (Denmark)

    Pedersen, Jens Myrup; Knudsen, Thomas Phillip; Madsen, Ole Brun

    A new routing scheme, Topological Routing, for large-scale networks is proposed. It allows for efficient routing without large routing tables as known from traditional routing schemes. It presupposes a certain level of order in the networks, known from Structural QoS. The main issues in applying...... Topological Routing to large-scale networks are discussed. Hierarchical extensions are presented along with schemes for shortest path routing, fault handling and path restoration. Further reserach in the area is discussed and perspectives on the prerequisites for practical deployment of Topological Routing...

  10. Route Optimization in Network Mobility

    Directory of Open Access Journals (Sweden)

    Md. Hasan Tareque

    2013-01-01

    Full Text Available NEtwork MObility (NEMO controls mobility of a number of mobile nodes in a comprehensive way using one or more mobile routers. To choose a route optimization scheme, it is very important to have a quantitative comparison of the available route optimization schemes. The focus of this paper is to analyze the degree of Route Optimization (RO, deploy-ability and type of RO supported by each class in general. The comparison shows the differences among the schemes in terms of issues, such as additional header, signaling and memory requirement. We classify the schemes established on the basic method for route optimization, and equal the schemes based on protocol overhead, such as header overhead, amount of signaling, and memory requirements. Lastly the performance of the classes of different schemes has to be estimated under norms such as available bandwidth, topology of the mobile network and mobility type.

  11. Local Routing in Convex Subdivisions

    DEFF Research Database (Denmark)

    Bose, Prosenjit; Durocher, Stephane; Mondal, Debajyoti;

    2015-01-01

    In various wireless networking settings, node locations determine a network’s topology, allowing the network to be modelled by a geometric graph drawn in the plane. Without any additional information, local geometric routing algorithms can guarantee delivery to the target node only in restricted...... classes of geometric graphs, such as triangulations. In order to guarantee delivery on more general classes of geometric graphs (e.g., convex subdivisions or planar subdivisions), previous local geometric routing algorithms required Θ(logn) state bits to be stored and passed with the message. We present...... the first local geometric routing algorithm using only one state bit to guarantee delivery on convex subdivisions and the first local geometric memoryless routing algorithm that guarantees delivery on edge-augmented monotone subdivisions (including all convex subdivisions) when the algorithm has knowledge...

  12. New TPG bus route 28

    CERN Multimedia

    2003-01-01

    Geneva's Public Transport services (TPG) have recently inaugurated a new bus line 28, connecting the La Tour Hospital in Meyrin to the international organisations in Geneva, via the airport. All signs associated with this route will be yellow in colour. Timetables and route details can be found at http://www.tpg.ch. Relations with the Host States Service http://www.cern.ch/relations/ Tel. 72848

  13. Dynamics of Air Passenger Transportation in Eastern Romania

    Directory of Open Access Journals (Sweden)

    Dan Păuna

    2013-10-01

    Full Text Available The concept of an air route mile is, of course, entirely different from that of a road or rail route mile. An air route is a direct service between two cities. The too-rapid development of the air route system must inevitably result in an average intensity of operations on the route, and this means the frequencies are low or high, or the airplanes used are profitable or unprofitable. The purpose of this paper is to emphasize air passenger dynamics in Romania and to calculate specific indicators regarding this calculation for the airports in eastern Romania in 2011t., this, because the air passenger featurea indicator passenger – kilometer, starting with 2009 no longer calculate for aviation and shipping.

  14. Reverse flood routing with the inverted Muskingum storage routing scheme

    Science.gov (United States)

    Koussis, A. D.; Mazi, K.; Lykoudis, S.; Argyriou, A.

    2010-09-01

    Motivation On occasion, flood related questions are posed in the reverse from the conventional sense, e.g.: Which inflow created the flow observed at cross-section X, or the flood profile observed along reach Y? This is a signal identification type problem (hydrologic forensics). A related question concerns the operation of a reservoir, via optimal outflow control, so as to minimise downstream flood damage. Solution of the aforementioned problems requires routing of floods in the upstream direction. This is an inverse problem, and as such it is not well posed. In routing against the wave propagation, small errors in the flow measurements, or rounding errors, are amplified leading to instability, i.e., to spurious, large changes in the response (inflow hydrograph). Therefore, for the reverse solution to be stable it must be constrained by a smoothness condition; this however does not ensure its uniqueness. Storage routing models as approximate diffusion wave models By appropriate choice of their parameter values, storage routing models approximate closely diffusion-wave (DW) behaviour, if dominant flood propagation mode is that of kinematic waves (KW), which is very often true. We solve the flood signal identification problem by reversing the Muskingum routing scheme. The Muskingum routing scheme derives from a first-order accurate FD discretisation of the KW equation yet yields second-order accurate DW solutions by matching the numerical diffusion coefficient of that KW equation solution scheme to the DW equation’s hydraulic diffusion coefficient. Formulation and testing of a reverse routing scheme based on Muskingum routing Theoretical analysis of the reversed Muskingum routing scheme yields nominal grid design rules; however, we study optimal grid design mainly by numerical experimentation. First, we reverse an exact outflow hydrograph (a single-wave solution of the convection-diffusion equation), and then demonstrate the scheme’s ability to reverse

  15. Vehicle Routing With User Generated Trajectory Data

    DEFF Research Database (Denmark)

    Ceikute, Vaida; Jensen, Christian S.

    Rapidly increasing volumes of GPS data collected from vehicles provide new and increasingly comprehensive insight into the routes that drivers prefer. While routing services generally compute shortest or fastest routes, recent studies suggest that local drivers often prefer routes that are neithe...

  16. The Consistent Vehicle Routing Problem

    Energy Technology Data Exchange (ETDEWEB)

    Groer, Christopher S [ORNL; Golden, Bruce [University of Maryland; Edward, Wasil [American University

    2009-01-01

    In the small package shipping industry (as in other industries), companies try to differentiate themselves by providing high levels of customer service. This can be accomplished in several ways, including online tracking of packages, ensuring on-time delivery, and offering residential pickups. Some companies want their drivers to develop relationships with customers on a route and have the same drivers visit the same customers at roughly the same time on each day that the customers need service. These service requirements, together with traditional constraints on vehicle capacity and route length, define a variant of the classical capacitated vehicle routing problem, which we call the consistent VRP (ConVRP). In this paper, we formulate the problem as a mixed-integer program and develop an algorithm to solve the ConVRP that is based on the record-to-record travel algorithm. We compare the performance of our algorithm to the optimal mixed-integer program solutions for a set of small problems and then apply our algorithm to five simulated data sets with 1,000 customers and a real-world data set with more than 3,700 customers. We provide a technique for generating ConVRP benchmark problems from vehicle routing problem instances given in the literature and provide our solutions to these instances. The solutions produced by our algorithm on all problems do a very good job of meeting customer service objectives with routes that have a low total travel time.

  17. Qos Failover Routing In Tethernet

    Directory of Open Access Journals (Sweden)

    Ankita Goswami

    2015-07-01

    Full Text Available Abstarct Tethering is a concept of sharing of internet of a device with other devices. Its a low-cost short-distance wireless technology which employs the frequency hopping practice in the globally available ISM band to keep away from interference. In the tethering to form a network there is a concept of piconet containing master and slaves. These piconets are connected together to establish a big network called scatternet. There are several aspects on which scatternet working depends like the piconets numbers and bridges the bridge role etc. Already established routes consume much more energy for the maintenance hence instead of this routes can be created on-demand. Thus consumption can be altered and routes flexibility will inclined. Failover is an another concept that I have included. Its about transferring ones control to the other device whenever first device is failed. In this thesis I have proposed a QoS failover routing that will proficiently form the routes with the QoS desires and will prevent the stoppage of transmission if the transmitting node fails. It will pass its control to another node and allow it to transmit instead of it.

  18. Optimization of OSPF Routing in IP Networks

    Science.gov (United States)

    Bley, Andreas; Fortz, Bernard; Gourdin, Eric; Holmberg, Kaj; Klopfenstein, Olivier; Pióro, Michał; Tomaszewski, Artur; Ümit, Hakan

    The Internet is a huge world-wide packet switching network comprised of more than 13,000 distinct subnetworks, referred to as Autonomous Systems (ASs) autonomous system AS . They all rely on the Internet Protocol (IP) internet protocol IP for transport of packets across the network. And most of them use shortest path routing protocols shortest path routing!protocols , such as OSPF or IS-IS, to control the routing of IP packets routing!of IP packets within an AS. The idea of the routing is extremely simple — every packet is forwarded on IP links along the shortest route between its source and destination nodes of the AS. The AS network administrator can manage the routing of packets in the AS by supplying the so-called administrative weights of IP links, which specify the link lengths that are used by the routing protocols for their shortest path computations. The main advantage of the shortest path routing policy is its simplicity, allowing for little administrative overhead. From the network engineering perspective, however, shortest path routing can pose problems in achieving satisfactory traffic handling efficiency. As all routing paths depend on the same routing metric routing!metric , it is not possible to configure the routing paths for the communication demands between different pairs of nodes explicitly or individually; the routing can be controlled only indirectly and only as a whole by modifying the routing metric. Thus, one of the main tasks when planning such networks is to find administrative link weights that induce a globally efficient traffic routing traffic!routing configuration of an AS. It turns out that this task leads to very difficult mathematical optimization problems. In this chapter, we discuss and describe exact integer programming models and solution approaches as well as practically efficient smart heuristics for such shortest path routing problems shortest path routing!problems .

  19. ACO based routing for MANETs

    CERN Document Server

    Arif, Mohammad

    2012-01-01

    Mobile ad hoc network (MANET) is a collection of wireless mobile nodes. It dynamically forms a temporary network without using any pre existing network infrastructure or centralized administration i.e. with minimal prior planning. All nodes have routing capabilities and forward data packets to other nodes in multi-hop fashion. As the network is dynamic, the network topology continuously experiences alterations during deployment. The biggest challenge in MANETs is to find a path between communicating nodes. The considerations of the MANET environment and the nature of the mobile nodes create further complications which results in the need to develop special routing algorithms to meet these challenges. Swarm intelligence, a bio-inspired technique, which has proven to be very adaptable in other problem domains, has been applied to the MANET routing problem as it forms a good fit to the problem. In ant societies the activities of the individuals are not regulated by any explicit form of centralized control but ar...

  20. Routing Algorithm Exploits Spatial Relations

    Science.gov (United States)

    Okino, Clayton; Jennings, Esther

    2004-01-01

    A recently developed routing algorithm for broadcasting in an ad hoc wireless communication network takes account of, and exploits, the spatial relationships among the locations of nodes, in addition to transmission power levels and distances between the nodes. In contrast, most prior algorithms for discovering routes through ad hoc networks rely heavily on transmission power levels and utilize limited graph-topology techniques that do not involve consideration of the aforesaid spatial relationships. The present algorithm extracts the relevant spatial-relationship information by use of a construct denoted the relative-neighborhood graph (RNG).

  1. le programme SET-Routes

    CERN Multimedia

    CERN Audiovisual Service

    2009-01-01

    Les routes de la science sont plus escarpées pour les femmes Le programme SET-Routes, qui visait à sensibiliser les jeunes filles à l’intérêt des carrières scientifiques, a pris fin en avril. Porté par l’EMBL, l’EMBO et le CERN, il a mis en place un réseau de femmes scientifiques, des ambassadrices qui se sont rendues dans les établissements scolaires européens pour parler de leur parcours scientifique.

  2. A Computer Simulation of the System-Wide Effects of Parallel-Offset Route Maneuvers

    Science.gov (United States)

    Lauderdale, Todd A.; Santiago, Confesor; Pankok, Carl

    2010-01-01

    Most aircraft managed by air-traffic controllers in the National Airspace System are capable of flying parallel-offset routes. This paper presents the results of two related studies on the effects of increased use of offset routes as a conflict resolution maneuver. The first study analyzes offset routes in the context of all standard resolution types which air-traffic controllers currently use. This study shows that by utilizing parallel-offset route maneuvers, significant system-wide savings in delay due to conflict resolution of up to 30% are possible. It also shows that most offset resolutions replace horizontal-vectoring resolutions. The second study builds on the results of the first and directly compares offset resolutions and standard horizontal-vectoring maneuvers to determine that in-trail conflicts are often more efficiently resolved by offset maneuvers.

  3. The Effects of the Emission Cost on Route Choices of International Container Ships

    Directory of Open Access Journals (Sweden)

    Hyangsook Lee

    2016-01-01

    Full Text Available Maritime freight shipping has increased significantly and air pollution from international ships has grown accordingly, having serious environmental effects all over the world. This paper analyzes the effects of the emission cost on ocean route choices, focusing on international container ships. First, the paper formulates a freight network model that captures decisions and interactions of ocean carriers and port terminal operators in the maritime freight transport system. Then, the emission cost is calculated based on an activity-based approach as a component of the ocean transportation cost function. A case study is examined to find if the emission cost affects ocean route choices. The results indicate that the optimal ocean route and transportation cost are changed distinctively due to the emission cost. The research discusses how the emission cost plays a role in route changes and why ocean carriers have to consider these costs in their routing decisions.

  4. Genetic algorithms for route discovery.

    Science.gov (United States)

    Gelenbe, Erol; Liu, Peixiang; Lainé, Jeremy

    2006-12-01

    Packet routing in networks requires knowledge about available paths, which can be either acquired dynamically while the traffic is being forwarded, or statically (in advance) based on prior information of a network's topology. This paper describes an experimental investigation of path discovery using genetic algorithms (GAs). We start with the quality-of-service (QoS)-driven routing protocol called "cognitive packet network" (CPN), which uses smart packets (SPs) to dynamically select routes in a distributed autonomic manner based on a user's QoS requirements. We extend it by introducing a GA at the source routers, which modifies and filters the paths discovered by the CPN. The GA can combine the paths that were previously discovered to create new untested but valid source-to-destination paths, which are then selected on the basis of their "fitness." We present an implementation of this approach, where the GA runs in background mode so as not to overload the ingress routers. Measurements conducted on a network test bed indicate that when the background-traffic load of the network is light to medium, the GA can result in improved QoS. When the background-traffic load is high, it appears that the use of the GA may be detrimental to the QoS experienced by users as compared to CPN routing because the GA uses less timely state information in its decision making.

  5. A route towards immune protection

    NARCIS (Netherlands)

    Groot Nibbelink, Milou

    2016-01-01

    This work describes a route towards an immune protective device for islet of Langerhans transplantation. We developed a protocol to use MIN6 β cells aggregates as pseudo-islets to overcome the donor shortage issue (chapter 3). In this thesis we explored two different immune protective strategies; a

  6. Dynamic Weather Routes Architecture Overview

    Science.gov (United States)

    Eslami, Hassan; Eshow, Michelle

    2014-01-01

    Dynamic Weather Routes Architecture Overview, presents the high level software architecture of DWR, based on the CTAS software framework and the Direct-To automation tool. The document also covers external and internal data flows, required dataset, changes to the Direct-To software for DWR, collection of software statistics, and the code structure.

  7. Arctic Routes to Fabled Lands

    NARCIS (Netherlands)

    Spies, Marijke

    1997-01-01

    Four hundred years ago Willem Barents set sail with two ships for the north via the Pole. Apart from this expedition, numerous other attempts were made by Dutch and Flemish mariners to find a northern trade route to China and Cathay. In this book, Marijke Spies relates the story of Olivier Brunel, t

  8. Naval Battleforce Networks Composite Routing

    Science.gov (United States)

    2007-11-02

    fashion by DHCP), restarts or recontigures the OSPi" daemon, starts advertising the attached subnet in its new wireless subnet, and data transfer starts...Policy Manager. studying extcnsions to PlM or source specific multicast pro,i,,.:als to enable dynamic policy based routing based on DS(’P or other

  9. How to choose the route.

    Science.gov (United States)

    Grecu, Irina

    2013-01-01

    Choosing the route for nutrition support delivery is one of the main steps in the algorithm of providing successful nutrition to the critically ill, but it is certainly not an easy process. The rationale should be guided not only by principles like physiology and benefit versus harm, but also by individual patient factors like feasibility, contraindications, predicted versus actual tolerance, and (most important) the timing for starting food delivery. Although oral nutrition is the more physiological route for feeding, it is seldom possible or sufficient in critically ill patients. Enteral nutrition, in the form of tube feeding, remains the best option in the absence of absolute contraindications, but many other factors should be taken into account. These include the importance of starting early and trying to achieve target nutrients delivery early, especially in previously undernourished or in most severely ill patients, as well as the gastrointestinal intolerance present in the majority of critically ill patients. Parenteral nutrition is an alternative route for nutrition delivery when the enteral one is impossible or insufficient. The most common complication when choosing this route is overfeeding, which has been associated with increased complications rate. On the other hand, the most common complication of enteral nutrition is underfeeding, which has also been associated with worse outcome and even increased mortality. Combining enteral with supplemental parenteral nutrition is therefore a rational approach for providing early and adequate nutritional support in the most severely ill patients.

  10. Vehicle Routing with Uncertain Demand

    NARCIS (Netherlands)

    R. Spliet (Remy)

    2013-01-01

    textabstractIn distribution networks a supplier transports goods from a distribution center to customers by means of vehicles with limited capacity. Drivers will drive routes on which they visit multiple customers to make deliveries. Typically, deliveries are made regularly and a fixed schedule is m

  11. Routing Protocols to Minimize the Number of Route Disconnections for Communication in Mobile Ad Hoc Networks

    Science.gov (United States)

    2009-09-01

    Routing Protocol MAODV [5] is the multicast extension of the well-known Ad hoc On-demand Distance Vector ( AODV ...extensions of the Dynamic Source Routing (DSR) protocol [4] or the Ad hoc On-demand Distance Vector ( AODV ) routing protocol [5]. The multi-path routing ...Multi-path Distance Vector (AOMDV) routing protocol [7], an extension of AODV to compute multiple loop-free link- disjoint routes ; (iii) AODV

  12. Optimum Route Selection for Vehicle Navigation

    Directory of Open Access Journals (Sweden)

    Dalip

    2016-02-01

    Full Text Available The objective of Optimum Route Selection for Vehicle Navigation System (ORSVNS article is to develop a system, which provides information about real time alternate routes to the drivers and also helps in selecting the optimal route among all the alternate routes from an origin to destination. Two types of query systems, special and general, are designed for drivers. Here, the criterion for route selection is introduced using primary and secondary road attributes. The presented methodology helps the drivers in better decision making to choose optimal route using fuzzy logic. For experimental results ORSVNS is tested over 220 km portion of Haryana state in India.

  13. Airport Activity Statistics of Certificated Route Air Carriers

    Science.gov (United States)

    1987-12-31

    Nin D - 0 0 ’ 0’ 0 C70 ’C7 1 0 > NE’ ( ’ ’ I , M In 0 N N 01a 0 0 0 7 C’ LA11 rCAa w 0’ w’ w C’)jL, : . LL3; . .5 8 CS) (7 (7 NCN U,4 GU 0A 0A 0 5 0 5 L...D InIA a~ N - A~ Ca in Nca R a 0)( 0-0 __NI_ V .)NN& 0L Ca C~C~ rCaa C4 r)--.CI 00 WOA- W IN CNC-C)A IOIIO an - N N MC4aI1f~4C I. 0 C~O 4 C AI~I0-0Na

  14. Airport Activity Statistics of Certificated Route Air Carriers.

    Science.gov (United States)

    1982-12-31

    2 76 so1 OC-10-30 2 2 1o ALL. TYPES 10271 3 10224 1300 1922b 99.10 31 22 b6-U, PESTIC 8-73 7-5001201) 7362, 33~ ALL TYPES 23b 236 231 236 q9.07 35...96.43 30 2--0. PESTIC 94-94 L, 2 61137AOL-l7d 37* 373 33 4󈨎%-417 ttp .0 04SC-? 64 164 is A&L TYPES Z021 2 7,321 70E4 .7,2 t 9 37 o. L7443~ . 4-2o6

  15. Airport Activity Statistics of Certificated Route Air Carriers.

    Science.gov (United States)

    1985-12-31

    Who 1 ’. SLACS 13 .S ... . 66 29010 51213 4!47 4650 43151 241994 350.17 153.47 2.98 67 6.0 41 i 4*73250---3(r123110: 1578 1755 15t7 63423 .01 6* 70...17.91 111.91 58.62187 UA WRIST IC---SCFDULE, 830 4.145 160 BOA "ISTC-S~hDULAD 4181.1 1.44.36 2.10 2.10 146.46III its TABLE 6EMPLIANED REVENUE

  16. Airport Activity Statistics of Certificated Route Air Carriers.

    Science.gov (United States)

    1980-12-31

    17936.31 32 13 ; %FASIIARD 54 OJF %IIC ----..... SCHEDULED 1 I30 170 1130 33012.71 9410.16 .12 5, 30 INFIRNAI I7NAL----SCHEuJLr) 246Lt 301 2456 64206...AtL 1. iLAVICkS 25 .09 .03 .02 .05 14 I~~~ Ca~ al .00 ’Ti1N CITlY N -.c lIN CITY AISI b.,STau~lI(.------SCH.0tULiL Ii 79 .04 9.50 9.50 95 71, A K N...BY TYPE Of SERVICE. BY COMUNITY. AND BY CAIBER I |2 M Ŕ’lt .. U 6.t4t.4 .. 301 .J ( "rrw Enla~’. L * T,..’.......I.... ..... . . .. o.1 *I, I S*tll

  17. Airport Activity Statistics of Certificated Route Air Carriers, 1992

    Science.gov (United States)

    1992-12-31

    AS 18,186 166.45 166.45 SANTA BARBARA N 0.00 (SANTA BARBARA ) 0.00 AA- AMERICAN AIRLINES...SANTA BARBARA (SANTA BARBARA ) ....................................... AA-AMERICAN AIRLINES ............ TOTAL ............. MD-80...OR ,MU, MYA OF WAAtUM coSnT CARPER OP "A7IlON ___ iM All AIow xwON HEL1AS M SCEDU SUNIMIt NEW YORK-,*lnwW NEW YOrU-m (WT 3orH ST HEUPr--- u COiUWI1Y

  18. Airport Activity Statistics of Certificated Route Air Carriers.

    Science.gov (United States)

    1983-12-31

    MnhsrCoveod Orange County Coos Bay. OR ... North Band /Coos Bay L4adington, MI ...... Mardstae/LudingtOn Corbin. KY ....... London/Corbi. Mandan, NID...a)0.*-81= 1188 1 a3 531 Mc410 &laws 0 A0 I’ll3I ISAL43304 SWISS .. 11 31 044 ru -~01 4 00 IWt1104 4 1903 24 03 bell . X, a &.0019 09 I as.& flOSS 104

  19. En Route/Terminal ATC (Air Traffic Control) Operations Concept.

    Science.gov (United States)

    1983-10-28

    been provided It is recognized that for events such as catastro - controllers interface phes, hi-jackings, or sensi- with pilots and control- tive U.S...idetiie .icat " nbokcd Tig ~ l ~ C nttt V. DrONe ~iy n ieto vco Itwddr lc’ PoutionSymbls tne mpced aeadof Wet)O~te w0b9f ,i29 6 Fre tack No ~i~t pln

  20. Air Pollution

    Science.gov (United States)

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, dust, ... a gas, is a major part of air pollution in cities. When ozone forms air pollution, it's ...

  1. Analytical Analysis of Vehicle Routing and Inventory Routing Problems

    Science.gov (United States)

    2007-11-02

    The objective of the project is to perform analytical analyses of heuristics for the Vehicle Routing Problem ( VRP ) and apply the results in models...asymptotic optimal solution value of the VRP with capacity and time window constraints and used it to develop a new and efficient algorithm. (2) Obtained a...characterization of the effectiveness of set partitioning formulations for VRPs . (3) Characterized the worst case behavior of the linear programming

  2. Technical Report: Sleep-Route - Routing through Sleeping Sensors

    OpenAIRE

    Sarkar, Chayan; Rao, Vijay S.; Prasad, R Venkatesha

    2014-01-01

    In this article, we propose an energy-efficient data gathering scheme for wireless sensor network called Sleep-Route, which splits the sensor nodes into two sets - active and dormant (low-power sleep). Only the active set of sensor nodes participate in data collection. The sensing values of the dormant sensor nodes are predicted with the help of an active sensor node. Virtual Sensing Framework (VSF) provides the mechanism to predict the sensing values by exploiting the data correlation among ...

  3. Capacity Constrained Routing Algorithms for Evacuation Route Planning

    Science.gov (United States)

    2006-05-04

    April 30, 2006 DRAFT 9 D. Scope and Outline of the Paper The main focus of the paper is on the analysis of a heuristic algorithm which effectively...CCRP Algorithms In this section, we present a generic description of the Capacity Constrained Route Planner (CCRP). CCRP is a heuristic algorithm which...qualifies to be a candidate algorithm. E. Solution Quality of CCRP Since CCRP is a heuristic algorithm , it does not produce optimal solutions for all

  4. Route Scherrer and Route Einstein closed for construction work

    CERN Multimedia

    2015-01-01

    Please note that Route Scherrer will be inaccessible for two and a half months from the beginning of March and that part of Route Einstein will be closed for two weeks from the end of February.   Figure 1. The part of Route Scherrer between Building 510 and Building 53 (see Figure 1) will be closed from the beginning of March until mid-May for civil engineering works.   The superheated water pipes supplying the buildings in this area date back to 1959 and therefore present a significant risk of leakage. In order to ensure the reliable supply of superheated water, and, by extension, heating, to all premises near the Main Building (i.e. Buildings 500, 501, 503, 60, 62, 63 and 64), a new buried service duct will be installed between the basements of Buildings 53 and 61 to house a new superheated water pipe. Figure 2. The following car parks will, however, remain accessible for the duration of the works: the Cèdres car park, the car park for Buildings 4 and 5, and the ca...

  5. Implementation of direct routing mobile IP for solving triangular routing

    Science.gov (United States)

    Jang, Jongwook; Jang, SeongHo; Park, Miri; Lee, Dae-bong

    2001-10-01

    Mobility support on the network layer is of special importance, as the network layer holds together the huge Internet with common protocol IP. Although based on possibility different wireless or wired technologies, all nodes of the network should be able to communicate. Therefore, mobile IP(an extension of the classical IP) has been designed which enablemobility in the Internet without changing existing wired systems. However, mobile IP leaves some points unsolved. Especially, if it comes to security, efficiency of the packet flow that is called triangular routing. Especially triangular routing can cause unnecessary overhead for the network. Furthermore latency can increase dramatically. This is particularly unfortunate if two communicating hosts are separated by transatlantic links. In order to this problem, many methods like IPv6 and ROMIP are proposed. But these methods have limitation. In other words, they have not compatibility because of needing modification of original IP scheme. Especially ROMIP is very complex and the overhead of control message and processing are serious. The problem of inconsistency of Binding caches may occur too. We therefore propose and analyze the performance of the DRMIP (Direct Routing Mobile IP) which do not modify IP source needed in the sender, is compatible with IP and Mobile IP.

  6. Scripted Mobile Network Routing in a Contested Environment

    Science.gov (United States)

    2008-03-01

    Protocol Comparisons Iwata measures on-demand routing , such as AODV , Fisheye State Routing (FSR...comparison between DSDV, CGSR, The Wireless Routing Protocol (WRP), AODV , DSR, TORA, Associativity-Based Routing (ABR) and Signal Stability Routing (SSR...with AODV . The modified routing does not change AODV , and can be used with any routing protocol . AODV is tested with and without the plan

  7. Multipath Routing Protocol for Effective Local Route Recovery in Mobile Ad hoc Network

    Directory of Open Access Journals (Sweden)

    S. K. Srivatsa

    2012-01-01

    Full Text Available Problem statement: In mobile ad hoc networks, frequent mobility during the transmission of data causes route failure which results in route rediscovery. In this, we propose multipath routing protocol for effective local route recovery in Mobile Ad hoc Networks (MANET. In this protocol, each source and destination pair establishes multiple paths in the single route discovery and they are cached in their route caches. Approach: The cached routes are sorted on the basis of their bandwidth availability. In case of route failure in the primary route, a recovery node which is an overhearing neighbor, detects it and establishes a local recovery path with maximum bandwidth from its route cache. Results: By simulation results, we show that the proposed approach improves network performance. Conclusion: The proposed route recovery management technique prevents the frequent collision and degradation in the network performance.

  8. Location Based Opportunistic Routing Protocol for Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Jubin Sebastian E

    2012-01-01

    Full Text Available : Most existing ad hoc routing protocols are susceptible to node mobility, especially for large-scale networks. This paper proposes a Location Based Opportunistic Routing Protocol (LOR to addresses the problem of delivering data packets for highly dynamic mobile ad hoc networks in a reliable and timely manner.This protocol takes advantage of the stateless property of geographic routing and the broadcast nature of wireless medium. When a data packet is sent out, some of the neighbor nodes that have overheard the transmission will serve as forwarding candidates, and take turn to forward the packet if it is not relayed by the specific best forwarder within a certain period of time. By utilizing such in-the-air backup, communication is maintained without being interrupted. The additional latency incurred by local route recovery is greatly reduced and the duplicate relaying caused by packet reroute is also decreased. Simulation results on NS2 verified the effectiveness of the proposed protocol with improvement in throughput by 28%.

  9. Comparison of on Demand Routing Protocols

    Directory of Open Access Journals (Sweden)

    Bharat Bhushan

    2013-02-01

    Full Text Available A routing protocol is used to facilitate communication in ad hoc network. The primary goal of such a routing protocol is to provide an efficient and reliable path between a pair of nodes. The routing protocols for ad hoc network can be categorized into three categories: table driven, on demand and hybrid routing. The table driven and hybrid routing strategies require periodic exchange of hello messages between nodes of the ad hoc network and thus have high processing and bandwidth requirements. On the other hand on demand routing strategy creates routes when required and hence is very much suitable for ad hoc network. This paper therefore examines the performance of three on demand routing protocols at application layer using QualNet-5.01 simulator.

  10. Model multivehicle routing dengan persaingan pasar

    OpenAIRE

    2011-01-01

    Multiple vehicle routing problem has potential real-word applications as it enables the study of strategic competition among private trucking companies in such ar- eas as the transportation of aggregates to construction sites. The multiple vehicle routing problem with profits and competition (MVRPPC) represents an extension of the vehicle routing problem in that it: incorporates competition into the routing process, maximizes profits rather than minimizes costs, and assumes that truc...

  11. QAODV: Improved Security Routing Protocol of AODV

    OpenAIRE

    Ruihui Mu; Wuqiang Zhang

    2013-01-01

    Network control system (NCS) has higher requirements on QoS index of the network, but MANET can hardly meet the demands of control systems because of its own characteristics. The paper improves AODV and proposes AODV routing protocol QAODV with certain QoS security in combination with NCS and MANET, and expounds routing detection, routing register and routing maintenance. Simulation results show that end-to-end delay and packet loss of QAODV reduces evidently compared with AODV, and the proto...

  12. A New Distributed Routing Protocol.

    Science.gov (United States)

    1984-01-01

    Kindm ’[t., BMnclh CntMU Consider a attuatJion in %, Adhd them am n n es0 ndh lidkd to at least ne &her node sudh that all moe a wwmwted. either...distributed Itn r that is cpable, of failsafe distributed routing. 37 ~L MANHATAN %SQ.ARE GP :,!: NETWORK, - CONNECTTVY S . .. . I ip p- t 0 4 Figure 4-3

  13. Locating Depots for Capacitated Vehicle Routing

    DEFF Research Database (Denmark)

    Gørtz, Inge Li; Nagarajan, Viswanath

    2011-01-01

    We study a location-routing problem in the context of capacitated vehicle routing. The input to k-LocVRP is a set of demand locations in a metric space and a fleet of k vehicles each of capacity Q. The objective is to locate k depots, one for each vehicle, and compute routes for the vehicles so...

  14. Verkeersveiligheidseffecten van Dynamische Route Informatie Panelen (DRIP's).

    NARCIS (Netherlands)

    2008-01-01

    The term Dynamic Route Information Panel (DRIP) is, also in the Netherlands, used for an electronic route information panel. A DRIP usually indicates if there are queues on the various routes to a particular destination, how long they are, and sometimes what the estimated journey time is. This is in

  15. The pyramidal capacitated vehicle routing problem

    DEFF Research Database (Denmark)

    Lysgaard, Jens

    2010-01-01

    This paper introduces the pyramidal capacitated vehicle routing problem (PCVRP) as a restricted version of the capacitated vehicle routing problem (CVRP). In the PCVRP each route is required to be pyramidal in a sense generalized from the pyramidal traveling salesman problem (PTSP). A pyramidal...

  16. Locating Depots for Capacitated Vehicle Routing

    DEFF Research Database (Denmark)

    Gørtz, Inge Li; Nagarajan, Viswanath

    2016-01-01

    We study a location-routing problem in the context of capacitated vehicle routing. The input to the k-location capacitated vehicle routing problem (k-LocVRP) consists of a set of demand locations in a metric space and a fleet of k identical vehicles, each of capacity Q. The objective is to locate k...

  17. A Survey on Distance Vector Routing Protocols

    CERN Document Server

    Tang, Linpeng

    2011-01-01

    In this paper we give a brief introduction to five different distance vector routing protocols (RIP, AODV, EIGRP, RIP-MTI and Babel) and give some of our thoughts on how to solve the count to infinity problem. Our focus is how distance vector routing protocols, based on limited information, can prevent routing loops and the count to infinity problem.

  18. Cultural Routes and Intangible Heritage

    Directory of Open Access Journals (Sweden)

    Enza Zabbini

    2012-08-01

    Full Text Available The theoretical interpretation of thematic routes helps to predict the effects on the territories visited by cultured tourists who want to enrich their cultural and emotional baggage. After the analysis of some interpretations, this paper will examine how the practical implementation of an itinerary approved by the Council of Europe has evolved over the years. And it will also reflect on the practical results in the areas involved in that project. "The Hannibal Pathway ", the main overland walk on the "Phoenician Route - Cultural Route recognized by the Council of Europe" – represents a case of study that allows to reflect over the impact of cultural tourism based on immaterial heritage. In fact, in the areas where the battle of 21 June 217 BC took place, nothing tangible is left, except the landscape that has kept its conformation intact. In these areas, thanks to the foresight of the local governments in the last three decades, the landscape of the plain has been preserved. This makes possible today to propose an historical path precisely based on the landscape and on the new techniques for the valorization of the heritage. In the Tuoro plain it is possible to see the battlefields, thus retracing the various stages of the battle, supported by the Documentation Centre of the Capra Palace and virtual reconstructions of high technical quality.

  19. Real-time routing control design for traffic networks with multi-route choices

    Institute of Scientific and Technical Information of China (English)

    罗莉华; 葛颖恩; 陈继红; 张方伟

    2016-01-01

    This work considers those road networks in which there are multi-route choices for bifurcation-destination (or origin-destination) pairs, and designs a real-time variable message sign (VMS)-based routing control strategy in the model predictive control (MPC) framework. The VMS route recommendation provided by the traffic management authority is directly considered as the control variable, and the routing control model is established, in which a multi-dimensional control vector is introduced to describe the influence of route recommendations on flow distribution. In the MPC framework, a system optimum routing strategy with the constraints regarding drivers’ acceptability with recommended routes is designed, which can not only meet the traffic management authority’s control requirement but also improve drivers’ satisfaction with the route guidance system. The simulation carried out shows that the proposed routing control can effectively mitigate traffic congestion, reduces followers’ time delay, and improves drivers’ satisfaction with routing control in road networks.

  20. Submarine Pipeline Routing Risk Quantitative Analysis

    Institute of Scientific and Technical Information of China (English)

    徐慧; 于莉; 胡云昌; 王金英

    2004-01-01

    A new method for submarine pipeline routing risk quantitative analysis was provided, and the study was developed from qualitative analysis to quantitative analysis.The characteristics of the potential risk of the submarine pipeline system were considered, and grey-mode identification theory was used. The study process was composed of three parts: establishing the indexes system of routing risk quantitative analysis, establishing the model of grey-mode identification for routing risk quantitative analysis, and establishing the standard of mode identification result. It is shown that this model can directly and concisely reflect the hazard degree of the routing through computing example, and prepares the routing selection for the future.

  1. Route selection for vehicle navigation and control

    OpenAIRE

    G. Pang; Chu, MH

    2007-01-01

    This paper presents an application of neural-fuzzy methodology for the problem of route selection in a typical vehicle navigation and control system. The idea of the primary attributes of a route is discussed, and a neural-fuzzy system is developed to help a user to select a route out of the many possible routes from an origin to the destination. The user may not adopt the recommendation provided by the system and choose an alternate route. One novel feature of the system is that the neural-f...

  2. Routing for wireless multi-hop networks

    CERN Document Server

    Hamid, Sherin Abdel; Takahara, Glen

    2013-01-01

    The focus of this brief is to identify what unifies and what distinguishes the routing functions in four wireless multi-hop network paradigms. The brief introduces a generic routing model that can be used as a foundation of wireless multi-hop routing protocol analysis and design. It demonstrates that such model can be adopted by any wireless multi-hop routing protocol. Also presented is a glimpse of the ideal wireless multi-hop routing protocol along with several open issues.

  3. Dynamic information routing in complex networks

    Science.gov (United States)

    Kirst, Christoph; Timme, Marc; Battaglia, Demian

    2016-01-01

    Flexible information routing fundamentally underlies the function of many biological and artificial networks. Yet, how such systems may specifically communicate and dynamically route information is not well understood. Here we identify a generic mechanism to route information on top of collective dynamical reference states in complex networks. Switching between collective dynamics induces flexible reorganization of information sharing and routing patterns, as quantified by delayed mutual information and transfer entropy measures between activities of a network's units. We demonstrate the power of this mechanism specifically for oscillatory dynamics and analyse how individual unit properties, the network topology and external inputs co-act to systematically organize information routing. For multi-scale, modular architectures, we resolve routing patterns at all levels. Interestingly, local interventions within one sub-network may remotely determine nonlocal network-wide communication. These results help understanding and designing information routing patterns across systems where collective dynamics co-occurs with a communication function. PMID:27067257

  4. VANET Routing Protocols: Pros and Cons

    CERN Document Server

    Paul, Bijan; Bikas, Md Abu Naser

    2012-01-01

    VANET (Vehicular Ad-hoc Network) is a new technology which has taken enormous attention in the recent years. Due to rapid topology changing and frequent disconnection makes it difficult to design an efficient routing protocol for routing data among vehicles, called V2V or vehicle to vehicle communication and vehicle to road side infrastructure, called V2I. The existing routing protocols for VANET are not efficient to meet every traffic scenarios. Thus design of an efficient routing protocol has taken significant attention. So, it is very necessary to identify the pros and cons of routing protocols which can be used for further improvement or development of any new routing protocol. This paper presents the pros and cons of VANET routing protocols for inter vehicle communication.

  5. A Genetic Algorithm on Inventory Routing Problem

    Directory of Open Access Journals (Sweden)

    Nevin Aydın

    2014-03-01

    Full Text Available Inventory routing problem can be defined as forming the routes to serve to the retailers from the manufacturer, deciding on the quantity of the shipment to the retailers and deciding on the timing of the replenishments. The difference of inventory routing problems from vehicle routing problems is the consideration of the inventory positions of retailers and supplier, and making the decision accordingly. Inventory routing problems are complex in nature and they can be solved either theoretically or using a heuristics method. Metaheuristics is an emerging class of heuristics that can be applied to combinatorial optimization problems. In this paper, we provide the relationship between vendor-managed inventory and inventory routing problem. The proposed genetic for solving vehicle routing problem is described in detail.

  6. MILITARY MULTI-HOP ROUTING PROTOCOL

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Military tactical network is one of the most important applications of ad hoc network. Currently the existing routing protocols are put forward based on the simple and universal network model which has the ability of multi-hop routing but cannot work efficiently in the special military applications. The narrow bandwidth and limited energy of the wireless network make general routing protocols seem to be more redundant.In order to satisfy military needs properly, this letter makes a detailed analysis of physical nodes and traffic distribution in military network, uses cross-layer design concept for reference, combines traffic characteristic of application layer with routing protocol design. It categorized routing problem as crucial routes and non-crucial routes which adopted separate maintenance methods. It not only realizes basic transmission function but also works efficiently. It is quite fit for military application.

  7. Research on Routing Protocol of Mobile Ad Hoc Network

    OpenAIRE

    Tuo Ming Fu; Che Min

    2016-01-01

    Routing protocol is an important content of mobile Ad Hoc. The typical mobile Ad Hoc network routing protocols is introduced. The advantages and disadvantages of these routing protocols are analyzed. A hybrid routing protocol is put forward based on this.

  8. Evolutionary air traffic flow management for large 3D-problems

    NARCIS (Netherlands)

    Kemenade, C.H.M. van; Akker, J.M. van den; Kok, J.N.

    1996-01-01

    We present an evolutionary tool to solve free-route Air Traffic Flow Management problems within a three-dimensional air space. This is the first evolutionary tool which solves free-route planning problems involving a few hundred aircraft. We observe that the importance of the recombination operator

  9. Enhancing Route Maintenance in RS-AODV

    Directory of Open Access Journals (Sweden)

    Gaurav J. Bhatt*,

    2014-05-01

    Full Text Available Mobile Ad hoc Networks (MANETs are temporary formed, infrastructure-less networks. The performance metrics degrades due to the unstable channel conditions, network connectivity, and mobility and resource limitations. To improve different performance metrics, various cross-layering techniques are used where different layers from protocol stack communications with each other via exchange of information. Ad hoc on demand Routing Protocol (AODV is a well reactive ad hoc routing protocol. We proposed RS-AODV (Route Stability based AODV, a modified version of AODV routing protocol, based on route discovery by utilizing Physical Layer information instead of the minimum hop count approach of the default distance vector algorithm. Our research will also elaborate how the proposed model uses the received Signal Strength (RSSI to find its route. We will focus on parameters like traffic throughput, response, time, packet loss, delay, link stability, optimal usage of battery resource to increase overall lifetime of a network. And also use novel approach "make before break" that starts finding alternate route when it seems link failure due to mobility of node. Simulation results show that RS-AODV has performance better that AODV routing protocol in terms of the metrics: End-to-End delay, Packet Delivery Ratio, Network Routing Load and number of route repairs.

  10. A Study Issues Related To Improve Route Stability In AODY Routing Protocol In VANET

    Directory of Open Access Journals (Sweden)

    Annu Mor

    2013-01-01

    Full Text Available Vehicular Ad Hoc Network (VANET is a sub class of mobile ad hoc networks. VANET provides wireless communication among vehicles and vehicle to road side equipments, according to IEEE 802.11 p standard for end to end communication between vehicles . For end to end communication between vehicles a routing protocols is used to find a route based on link properties. One of the most important routing protocols used in ad hoc networks is AODV. This protocol is connectivity based reactive protocol that searches routes only when they are needed. It always exchanges control packets between neighbor nodes for routing. In this article author present cross layer technique that find channel security at link layer to AODV routing protocol to improve the communication in vehicles for safety purpose. To eliminate route discovery routers, propose PAODV as routing protocol. It improves AODV control overhead and makes routes more stable.

  11. Wireless Mesh Network Routing Under Uncertain Demands

    Science.gov (United States)

    Wellons, Jonathan; Dai, Liang; Chang, Bin; Xue, Yuan

    Traffic routing plays a critical role in determining the performance of a wireless mesh network. Recent research results usually fall into two ends of the spectrum. On one end are the heuristic routing algorithms, which are highly adaptive to the dynamic environments of wireless networks yet lack the analytical properties of how well the network performs globally. On the other end are the optimal routing algorithms that are derived from the optimization problem formulation of mesh network routing. They can usually claim analytical properties such as resource use optimality and throughput fairness. However, traffic demand is usually implicitly assumed as static and known a priori in these problem formulations. In contrast, recent studies of wireless network traces show that the traffic demand, even being aggregated at access points, is highly dynamic and hard to estimate. Thus, to apply the optimization-based routing solution in practice, one must take into account the dynamic and uncertain nature of wireless traffic demand. There are two basic approaches to address the traffic uncertainty in optimal mesh network routing (1) predictive routing that infers the traffic demand with maximum possibility based in its history and optimizes the routing strategy based on the predicted traffic demand and (2) oblivious routing that considers all the possible traffic demands and selects the routing strategy where the worst-case network performance could be optimized. This chapter provides an overview of the optimal routing strategies for wireless mesh networks with a focus on the above two strategies that explicitly consider the traffic uncertainty. It also identifies the key factors that affect the performance of each routing strategy and provides guidelines towards the strategy selection in mesh network routing under uncertain traffic demands.

  12. The Pyramidal Capacitated Vehicle Routing Problem

    DEFF Research Database (Denmark)

    Lysgaard, Jens

    This paper introduces the Pyramidal Capacitated Vehicle Routing Problem (PCVRP) as a restricted version of the Capacitated Vehicle Routing Problem (CVRP). In the PCVRP each route is required to be pyramidal in a sense generalized from the Pyramidal Traveling Salesman Problem (PTSP). A pyramidal...... found in many optimal solutions to CVRP instances. An optimal solution to the PCVRP may therefore be useful in itself as a heuristic solution to the CVRP. Further, an attempt can be made to find an even better CVRP solution by solving a TSP, possibly leading to a non-pyramidal route, for each...... of the routes in the PCVRP solution. This paper develops an exact branch-and-cut-and-price (BCP) algorithm for the PCVRP. At the pricing stage, elementary routes can be computed in pseudo-polynomial time in the PCVRP, unlike in the CVRP. We have therefore implemented pricing algorithms that generate only...

  13. Zone routing in a torus network

    Science.gov (United States)

    Chen, Dong; Heidelberger, Philip; Kumar, Sameer

    2013-01-29

    A system for routing data in a network comprising a network logic device at a sending node for determining a path between the sending node and a receiving node, wherein the network logic device sets one or more selection bits and one or more hint bits within the data packet, a control register for storing one or more masks, wherein the network logic device uses the one or more selection bits to select a mask from the control register and the network logic device applies the selected mask to the hint bits to restrict routing of the data packet to one or more routing directions for the data packet within the network and selects one of the restricted routing directions from the one or more routing directions and sends the data packet along a link in the selected routing direction toward the receiving node.

  14. Dynamic information routing in complex networks

    CERN Document Server

    Kirst, Christoph; Battaglia, Demian

    2015-01-01

    Flexible information routing fundamentally underlies the function of many biological and artificial networks. Yet, how such systems may specifically communicate and dynamically route information is not well understood. Here we identify a generic mechanism to route information on top of collective dynamical reference states in complex networks. Switching between collective dynamics induces flexible reorganization of information sharing and routing patterns, as quantified by delayed mutual information and transfer entropy measures between activities of a network's units. We demonstrate the power of this generic mechanism specifically for oscillatory dynamics and analyze how individual unit properties, the network topology and external inputs coact to systematically organize information routing. For multi-scale, modular architectures, we resolve routing patterns at all levels. Interestingly, local interventions within one sub-network may remotely determine non-local network-wide communication. These results help...

  15. Vehicle routing problem in investment fund allocation

    Science.gov (United States)

    Mamat, Nur Jumaadzan Zaleha; Jaaman, Saiful Hafizah; Ahmad, Rokiah Rozita; Mohd, Ismail

    2013-04-01

    Since its introduction by Dantzig and Ramser in 1959, vehicle routing problem keeps evolving in theories, applications and variability. The evolution in computing and technology are also important contributors to research in solving vehicle routing problem. The main sectors of interests among researchers and practitioners for vehicle routing problem are transportation, distribution and logistics. However, literature found that concept and benefits of vehicle routing problem are not taken advantages of by researchers in the field of investment. Other methods found used in investment include multi-objective programming, linear programming, goal programming and integer programming. Yet the application of vehicle routing problem is not fully explored. A proposal on a framework of the fund allocation optimization using vehicle routing problem is presented here. Preliminary results using FTSE Bursa Malaysia data testing the framework are also given.

  16. Final Environmental Assessment Addressing the Construction, Operation, and Maintenance of a New Fire Station at Kirtland Air Force Base, New Mexico

    Science.gov (United States)

    2012-05-01

    Route 31 – Wyoming Boulevard; Route 2 – Eubank Boulevard; Route 217 – Downtown-Kirtland AFB Limited; and Route 222 – Rio Bravo-Albuquerque...statutory framework for “Asbestos Hazard Emergency Response,” which applies only to schools. TSCA Title III, “Indoor Radon Abatement,” states indoor...air in buildings of the United States should be as free of radon as the outside ambient air. Federal agencies are required to conduct studies on

  17. A Generalized Assignment Heuristic for Vehicle Routing

    Science.gov (United States)

    1979-08-01

    problem by ( VRP ). L. . . . .. i -3- Formulation of the Vehicle Routing Problem ( VRP ) min Z c X. (1)ijk 1) i jk S.t. Z aiYik < bk , k ,...,K (2) 1...Fisher and Ramchandran Jaikumar University of Pennsylvania August, 1979 ABSTR_2T We consider a common variant of the vehicle routing problem in which a...minimum size fleet that can feasibly service the specified demand. 1. Intrcduction Vehicle routing is a challenging logistics management

  18. Distributed algorithms for resource allocation and routing

    OpenAIRE

    Hu, Zengjian

    2007-01-01

    In this thesis, we study distributed algorithms in the context of two fundamental problems in distributed systems, resource allocation and routing. Resource allocation studies how to distribute workload evenly to resources. We consider two different resource allocation models, the diffusive load balancing and the weighted balls-into-bins games. Routing studies how to deliver messages from source to estination efficiently. We design routing algorithms for broadcasting and gossiping in ad hoc n...

  19. Gossip Based Ad-Hoc Routing

    OpenAIRE

    Haas, Zygmunt; Halpern, Joseph Y.; Li, Erran L.

    2002-01-01

    Many ad hoc routing protocols are based on some variant of flooding. Despite various optimizations, many routing messages are propagated unnecessarily. We propose a gossiping-based approach, where each node forwards a message with some probability, to reduce the overhead of the routing protocols. Gossiping exhibits bimodal behavior in sufficiently large networks: in some executions, the gossip dies out quickly and hardly any node gets the message; in the remaining executions, a substantial fr...

  20. Scheduling and routing Tactical Aerial Reconnaissance Vehicles

    OpenAIRE

    1990-01-01

    Approved for public release; distribution unlimited. In this thesis we study the Marine Corps Tactical Aerial Reconnaissance Vehicle routing and scheduling problem. the present method of routing and scheduling is presented, along with possible implications for routing and scheduling when future expansion of vehicle assets becomes available. A review of current literature is given and comparisons are drawn between our problem and recent work. A model for the problem, which we call the Multi...

  1. Evaluation of Night Route Network on Flight Efficiency in Europe

    Directory of Open Access Journals (Sweden)

    Tomislav Mihetec

    2011-09-01

    Full Text Available There are many different concepts and definitions for the flight efficiency, where every stakeholder involved in air transport has its own perception on flight efficiency. Flight efficiency concept is based on trade-offs between safety, airspace capacity, fuel consumption, flying distance, time distance, time cost, fuel cost etc. Flight time and flying distance which has impact to fuel burn and operation costs to airspace users are mainly generated by deviations from the optimum trajectories. According to the Performance Review Commission (PRC Report in 2009 average en-route extension in Europe was 47.6 km, with the year on year improvement of 1.2 km. The PRC Report emphasized that there is constant increase of medium/long haul flights operated by aircraft operators in Europe while short haul flights are decreasing. One of the issues, concerning flight efficiency in Europe, is that aircraft operators are not using night routes sufficient during flight planning process. This paper is presenting flight efficiency for the traffic demand using night route network and not using it at all. Flight inefficiency is expresses by the agreed performance indicators: distance difference (NM, duration difference (min, fuel combustion difference (kg and CO2 emission (t environmental indicator.

  2. Flying Ad-Hoc Networks: Routing Protocols, Mobility Models, Issues

    Directory of Open Access Journals (Sweden)

    Muneer Bani Yassein

    2016-06-01

    Full Text Available Flying Ad-Hoc Networks (FANETs is a group of Unmanned Air Vehicles (UAVs which completed their work without human intervention. There are some problems in this kind of networks: the first one is the communication between (UAVs. Various routing protocols introduced classified into three categories, static, proactive, reactive routing protocols in order to solve this problem. The second problem is the network design, which depends on the network mobility, in which is the process of cooperation and collaboration between the UAV. Mobility model of FANET is introduced in order to solve this problem. In Mobility Model, the path and speed variations of the UAV and represents their position are defined. As of today, Random Way Point Model is utilized as manufactured one for Mobility in the greater part of recreation situations. The Arbitrary Way Point model is not relevant for the UAV in light of the fact that UAV do not alter their course and versatility, speed quickly at one time because of this reason, we consider more practical models, called Semi-Random Circular Movement (SRCM Mobility Model. Also, we consider different portability models, Mission Plan-Based (MPB Mobility Model, Pheromone-Based Model. Moreover, Paparazzi Mobility Model (PPRZM. This paper presented and discussed the main routing protocols and main mobility models used to solve the communication, cooperation, and collaboration in FANET networks.

  3. Shortest Paths and Vehicle Routing

    DEFF Research Database (Denmark)

    Petersen, Bjørn

    This thesis presents how to parallelize a shortest path labeling algorithm. It is shown how to handle Chvátal-Gomory rank-1 cuts in a column generation context. A Branch-and-Cut algorithm is given for the Elementary Shortest Paths Problem with Capacity Constraint. A reformulation of the Vehicle R...... Routing Problem based on partial paths is presented. Finally, a practical application of finding shortest paths in the telecommunication industry is shown.......This thesis presents how to parallelize a shortest path labeling algorithm. It is shown how to handle Chvátal-Gomory rank-1 cuts in a column generation context. A Branch-and-Cut algorithm is given for the Elementary Shortest Paths Problem with Capacity Constraint. A reformulation of the Vehicle...

  4. Routing Issues in Opportunistic Networks

    Science.gov (United States)

    Conti, Marco; Crowcroft, Jon; Giordano, Silvia; Hui, Pan; Nguyen, Hoang Anh; Passarella, Andrea

    The opportunistic networking idea stems from the critical review of the research field on Mobile Ad hoc Networks (MANET). After more than ten years of research in the MANET field, this promising technology still has not massively entered the mass market. One of the main reasons of this is nowadays seen in the lack of a practical approach to the design of infrastructure-less multi-hop ad hoc networks [186, 185]. One of the main approaches of conventional MANET research is to design protocols that mask the features of mobile networks via the routing (and transport) layer, so as to expose to higher layers an Internet-like network abstraction. Wireless networks’ peculiarities, such as mobility of users, disconnection of nodes, network partitions, links’ instability, are seen—as in the legacy Internet—as exceptions. This often results in the design of MANET network stacks that are significantly complex and unstable [107].

  5. A Privacy-Preserving Prediction Method for Human Travel Routes

    Directory of Open Access Journals (Sweden)

    Wen-Chen Hu

    2014-12-01

    Full Text Available This paper proposes a kind of location-based research, human travel route prediction, which is to predict the track of a subject's future movements. The proposed method works as follows. The mobile user sends his/her current route along with several dummy routes to the server by using a 3D route matrix, which encodes a set of routes. The server restores the routes from the 3D matrix and matches the restored routes to the saved routes. The predicted route is found as the trunk of the tree, which is built by superimposing the matching results. The server then sends the predicted routes back to the user, who will apply the predicted route to a real-world problem such as traffic control and planning. Preliminary experimental results show the proposed method successfully predicts human travel routes based on current and previous routes. User privacy is also rigorously protected by using a simple method of dummy routes.

  6. US Hazardous Materials Routes, Geographic WGS84, BTS (2006) [hazardous_material_routes_BTS_2006

    Data.gov (United States)

    Louisiana Geographic Information Center — The Federal Motor Carrier Safety Administration (FMCSA) Hazardous Material Routes were developed using the 2004 First Edition TIGER/Line files. The routes are...

  7. Dynamic Route Shortening and Route Repairing Mechanism for Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    T. R. Rangaswamy

    2012-01-01

    Full Text Available Problem statement: Ad hoc Networks are wireless networks without any fixed infrastructure. The network topology changes frequently and unpredictably due to the random movement of the nodes. The ad hoc on Demand Distant Vector Routing (AODV protocol works in a dynamic fashion, by establishing a route on demand and continues that route until it breaks. Due to the changing network topology of ad hoc networks, if other routes with less hop count become available, the network topology is not able to adapt until the route break occurs. Hence in the route shortening scheme is some redundant nodes in the active route is replaced with a node that is not on the active route. When there is any link failure between any two nodes, the alternative route with optimum route to be constructed and not sending RRER message to the source node to initiate the route discovery process again. Approach: This study proposes a new routing protocol called, Dynamic Route Shortening and Repairing mechanism (DRSR. The route shortening is incorporated with route repairing mechanism, to improve the performance of the AODV. The route shortening scheme works by replacing some redundant nodes in the active route, with a node that is not on the active route. If there is a link failure between the two nodes, the route repairing mechanism repairs the route, by using the nodes that are close enough to the route to overhear the message. Whenever the links go down, the DRSR replaces the failed links with the optimum route that is adjacent to the main route and not sending and RRER message to the source node to initiate the route discovery process again. The alternative route construction process could be initiated at any time, not just when a route has failed. The dynamically constructed alternative route’s information is passed on to the upstream nodes, which then determine by themselves when to direct their packets to the Normal 0 false false false EN-US X

  8. Bus Routes, Marta Bus Routes located in Transportation database, Published in unknown, City of Roswell, GA.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Bus Routes dataset as of unknown. It is described as 'Marta Bus Routes located in Transportation database'. Data by this publisher are often provided in State...

  9. Urban Freight Truck Routing under Stochastic Congestion and Emission Considerations

    Directory of Open Access Journals (Sweden)

    Taesung Hwang

    2015-05-01

    Full Text Available Freight trucks are known to be a major source of air pollutants as well as greenhouse gas emissions in U.S. metropolitan areas, and they have significant effects on air quality and global climate change. Emissions from freight trucks during their deliveries should be considered by the trucking service sector when they make routing decisions. This study proposes a model that incorporates total delivery time, various emissions including CO2, VOC, NOX, and PM from freight truck activities, and a penalty for late or early arrival into the total cost objective of a stochastic shortest path problem. We focus on urban transportation networks in which random congestion states on each link follows an independent probability distribution. Our model finds the best truck routing on a given network so as to minimize the expected total cost. This problem is formulated into a mathematical model, and two solution algorithms including a dynamic programming approach and a deterministic shortest path heuristic are proposed. Numerical examples show that the proposed approach performs very well even for the large-size U.S. urban networks.

  10. A New Approach to an Automated Air Traffic Control

    Institute of Scientific and Technical Information of China (English)

    Patchev Dragoljub

    2014-01-01

    This paper identifies areas of improvements of the air traffic control system and proposes modification of the concept of automation by using available technologies. With the proposed modification, the current Europe wide en route network structure can be modified in order to make routes more optimal. For this new route network structure, a new concept of automation will be used to manage with the air traffic. The first identified area of improvement is implementation of automation process that will enable decentralization of the air traffic control functionality to each individual aircraft and this will be achieved through automated routing of the aircrafts and CD&R (conflict detection and resolution). The FMS (flight management system) at the aircraft will make decisions for the optimal flight route based on the sensor inputs, information on selection of the routes, next hope points and flight levels, all received by ADS-B (automatic dependant surveillance-broadcast). The second area is processing the information about the deviation from the optimal route as in flight plan due to a traffic management (vectoring, level change) and taking it into consideration when further actions are undertaken. For each action, a cost factor will be calculated from the fuel burned for that action. This factor will be used to select conflict resolution protocol. The proposed concept shall increase the capacity of the network, and enable the air traff~c more efficient and more environmentally friendly while maintaining safe separation.

  11. KREAM: Korean Radiation Exposure Assessment Model for Aviation Route Dose

    Science.gov (United States)

    Hwang, J.; Dokgo, K.; Choi, E. J.; Kim, K. C.; Kim, H. P.; Cho, K. S. F.

    2014-12-01

    Since Korean Air has begun to use the polar route from Seoul/ICN airport to New York/JFK airport on August 2006, there are explosive needs for the estimation and prediction against cosmic radiation exposure for Korean aircrew and passengers in South Korea from public. To keep pace with those needs of public, Korean government made the law on safety standards and managements of cosmic radiation for the flight attendants and the pilots in 2013. And we have begun to develop our own Korean Radiation Exposure Assessment Model (KREAM) for aviation route dose since last year funded by Korea Meteorological Administration (KMA). GEANT4 model and NRLMSIS 00 model are used for calculation of the energetic particles' transport in the atmosphere and for obtaining the background atmospheric neutral densities depending on altitude. For prediction the radiation exposure in many routes depending on the various space weather effects, we constructed a database from pre-arranged simulations using all possible combinations of R, S, and G, which are the space weather effect scales provided by the National Oceanic and Atmospheric Administration (NOAA). To get the solar energetic particles' spectrum at the 100 km altitude which we set as a top of the atmospheric layers in the KREAM, we use ACE and GOES satellites' proton flux observations. We compare the results between KREAM and the other cosmic radiation estimation programs such as CARI-6M which is provided by the Federal Aviation Agency (FAA). We also validate KREAM's results by comparison with the measurement from Liulin-6K LET spectrometer onboard Korean commercial flights and Korean Air Force reconnaissance flights.

  12. What Is the Best Route? Route-Finding Strategies of Middle School Students Using GIS

    Science.gov (United States)

    Wigglesivorth, John C.

    2003-01-01

    This paper summarizes a research project conducted to investigate the strategies developed by middle school students to solve a route-finding problem using Arc View GIS software. Three different types of route-finding strategies were identified. Some students were visual route-finders and used a highly visual strategy; others were logical route…

  13. Layout and Routing Methods for Warehouses

    NARCIS (Netherlands)

    K.J. Roodbergen (Kees-Jan)

    2001-01-01

    textabstractLayout and Routing Methods for Warehouses discusses aspects of order picking in warehouses. Order picking is the process by which products are retrieved from storage to meet customer demand. Various new routing methods are introduced to determine efficient sequences in which products hav

  14. Routing in Optical and Stochastic Networks

    NARCIS (Netherlands)

    Yang, S.

    2015-01-01

    In most types of networks (e.g., optical or transportation networks), finding one or more best paths from a source to a destination, is one of the biggest concerns of network users and providers. This process is known as routing. The routing problems differ accordingly depending on different applica

  15. Classification of Dynamic Vehicle Routing Systems

    DEFF Research Database (Denmark)

    Larsen, Allan; Madsen, Oli B.G.; Solomon, Marius M.

    2007-01-01

    This chapter discusses important characteristics seen within dynamic vehicle routing problems. We discuss the differences between the traditional static vehicle routing problems and its dynamic counterparts. We give an in-depth introduction to the degree of dynamism measure which can be used...

  16. Secure Geographic Routing Protocols: Issues and Approaches

    CERN Document Server

    sookhak, Mehdi; Haghparast, Mahboobeh; ISnin, Ismail Fauzi

    2011-01-01

    In the years, routing protocols in wireless sensor networks (WSN) have been substantially investigated by researches. Most state-of-the-art surveys have focused on reviewing of wireless sensor network .In this paper we review the existing secure geographic routing protocols for wireless sensor network (WSN) and also provide a qualitative comparison of them.

  17. Joint Route Planning under Varying Market Conditions

    NARCIS (Netherlands)

    Cruijssen, F.C.A.M.; Braysy, O.; Dullaert, W.; Fleuren, H.A.; Salomon, M.

    2006-01-01

    Purpose - To provide empirical evidence on the level of savings that can be attained by joint route planning and how these savings depend on specific market characteristics.Design/methodology/approach - Joint route planning is a measure that companies can take to decrease the costs of their distribu

  18. TBRF: Trust Based Routing Framework for WSNs

    Directory of Open Access Journals (Sweden)

    Kushal Gulaskar

    2014-03-01

    Full Text Available The multi-hop routing in wireless sensor networks (WSNs offers little protection against identity deception through replaying routing information. An adversary can exploit this defect to launch various harmful or even devastating attacks against the routing protocols, including sinkhole attacks, wormhole attacks and Sybil attacks. The situation is further aggravated by mobile and harsh network conditions. Traditional cryptographic techniques or efforts at developing trust-aware routing protocols do not effectively address this severe problem. To secure the WSNs against adversaries misdirecting the multi-hop routing, we have designed and implemented TBRF, a robust trust-aware routing framework for dynamic WSNs. Without tight time synchronization or known geographic information, TBRF provides trustworthy and energy-efficient route. Most importantly, TBRF proves effective against those harmful attacks developed out of identity deception; the resilience of TBRF is verified through extensive evaluation with both simulation and empirical experiments on large-scale WSNs under various scenarios including mobile and RF-shielding network conditions. Further, we have implemented a low-overhead TBRF module in TinyOS; as demonstrated, this implementation can be incorporated into existing routing protocols with the least effort. Based on TBRF, we also demonstrated a proof-of-concept mobile target detection application that functions well against an anti-detection mechanism

  19. Performance Evaluation of Routing Protocols in MANET

    Directory of Open Access Journals (Sweden)

    Smitha Sunny

    2015-01-01

    Full Text Available Mobile Ad-Hoc Network (MANET is an autonomous system that is composed of the mobile nodes which communicates through wireless links without any preexisting infrastructure. MANET is a collection of mobile nodes which can self-organize freely and dynamically into arbitrary and temporary network topologies. Mobile nodes in ad-hoc networks function as a router and can dynamically establish routes among themselves by means of a routing protocol. Routing protocols in mobile ad-hoc network helps node to send and receive packets. Therefore, selection of an appropriate routing protocol is an integral part of establishing a MANET. A suitable and effective routing mechanism helps to extend the successful deployment of mobile ad-hoc networks. An attempt has been made to compare the performance between on-demand reactive routing protocols namely AODV, DSR and proactive routing protocol namely DSDV for Constant Bit Rate (CBR traffic by varying network scope i.e. number of participating nodes as well as by varying the speed. The parameters used for evaluation are Packet delivery ratio (PDR, Normalized routing overhead, Average end to end delay (Delay, Throughput and Average Energy consumption. The simulations are carried out using Network Simulator NS2:34.

  20. Optimizing departure times in vehicle routes

    NARCIS (Netherlands)

    Kok, A.L.; Hans, E.W.; Schutten, J.M.J.

    2011-01-01

    Most solution methods for the vehicle routing problem with time windows (VRPTW) develop routes from the earliest feasible departure time. In practice, however, temporary traffic congestion make such solutions non-optimal with respect to minimizing the total duty time. Furthermore, the VRPTW does not

  1. Optimizing departure times in vehicle routes

    NARCIS (Netherlands)

    Kok, A.L.; Hans, E.W.; Schutten, J.M.J.

    2008-01-01

    Most solution methods for the vehicle routing problem with time windows (VRPTW) develop routes from the earliest feasible departure time. However, in practice, temporal traffic congestions make that such solutions are not optimal with respect to minimizing the total duty time. Furthermore, VRPTW sol

  2. On green routing and scheduling problem

    CERN Document Server

    Touati, Nora

    2012-01-01

    The vehicle routing and scheduling problem has been studied with much interest within the last four decades. In this paper, some of the existing literature dealing with routing and scheduling problems with environmental issues is reviewed, and a description is provided of the problems that have been investigated and how they are treated using combinatorial optimization tools.

  3. On green routing and scheduling problem

    OpenAIRE

    Touati, Nora; Jost, Vincent

    2011-01-01

    The vehicle routing and scheduling problem has been studied with much interest within the last four decades. In this paper, some of the existing literature dealing with routing and scheduling problems with environmental issues is reviewed, and a description is provided of the problems that have been investigated and how they are treated using combinatorial optimization tools.

  4. Secure Geographic Routing Protocols: Issues and Approaches

    Directory of Open Access Journals (Sweden)

    Mehdi sookhak

    2011-09-01

    Full Text Available In the years, routing protocols in wireless sensor networks (WSN have been substantially investigated by researches Most state-of-the-art surveys have focused on reviewing of wireless sensor network .In this paper we review the existing secure geographic routing protocols for wireless sensor network (WSN and also provide a qualitative comparison of them.

  5. Integrated Routing Protocol for Opportunistic Networks

    CERN Document Server

    Verma, Anshul

    2012-01-01

    In opportunistic networks the existence of a simultaneous path is not assumed to transmit a message between a sender and a receiver. Information about the context in which the users communicate is a key piece of knowledge to design efficient routing protocols in opportunistic networks. But this kind of information is not always available. When users are very isolated, context information cannot be distributed, and cannot be used for taking efficient routing decisions. In such cases, context oblivious based schemes are only way to enable communication between users. As soon as users become more social, context data spreads in the network, and context based routing becomes an efficient solution. In this paper we design an integrated routing protocol that is able to use context data as soon as it becomes available and falls back to dissemination based routing when context information is not available. Then, we provide a comparison between Epidemic and PROPHET, these are representative of context oblivious and co...

  6. Individuality in bird migration: routes and timing.

    Science.gov (United States)

    Vardanis, Yannis; Klaassen, Raymond H G; Strandberg, Roine; Alerstam, Thomas

    2011-08-23

    The exploration of animal migration has entered a new era with individual-based tracking during multiple years. Here, we investigated repeated migratory journeys of a long-distance migrating bird, the marsh harrier Circus aeruginosus, in order to analyse the variation within and between individuals with respect to routes and timing. We found that there was a stronger individual repeatability in time than in space. Thus, the annual timing of migration varied much less between repeated journeys of the same individual than between different individuals, while there was considerable variation in the routes of the same individual on repeated journeys. The overall contrast in repeatability between time and space was unexpected and may be owing to strong endogenous control of timing, while short-term variation in environmental conditions (weather and habitat) might promote route flexibility. The individual variation in migration routes indicates that the birds navigate mainly by other means than detailed route recapitulation based on landmark recognition.

  7. Location and Routing of the Defense Courier Service Aerial Network

    Science.gov (United States)

    1991-03-01

    The Vehicle Routing Problem ................ 8 Vehicle Routing Problem Modifications ...... .0 Multiple Depot Problems...several specific formulations are applicable to the DCS aerial network. Those addressed in this review include: 1) the Vehicle Routing Problem (VRP); 2...methodologies show great promise for adaptation to the DCS network. The Vehicle Routing Problem The Travelling Salesman Problem seeks the shortest route which

  8. Guard Sets for Onion Routing

    Directory of Open Access Journals (Sweden)

    Hayes Jamie

    2015-06-01

    Full Text Available “Entry” guards protect the Tor onion routing system from variants of the “predecessor” attack, that would allow an adversary with control of a fraction of routers to eventually de-anonymize some users. Research has however shown the three guard scheme has drawbacks and Dingledine et al. proposed in 2014 for each user to have a single long-term guard. We first show that such a guard selection strategy would be optimal if the Tor network was failure-free and static. However under realistic failure conditions the one guard proposal still suffers from the classic fingerprinting attacks, uniquely identifying users. Furthermore, under dynamic network conditions using single guards offer smaller anonymity sets to users of fresh guards. We propose and analyze an alternative guard selection scheme by way of grouping guards together to form shared guard sets. We compare the security and performance of guard sets with the three guard scheme and the one guard proposal. We show guard sets do provide increased resistance to a number of attacks, while foreseeing no significant degradation in performance or bandwidth utilization.

  9. Drug targeting through pilosebaceous route.

    Science.gov (United States)

    Chourasia, Rashmi; Jain, Sanjay K

    2009-10-01

    Local skin targeting is of interest for the pharmaceutical and the cosmetic industry. A topically applied substance has basically three possibilities to penetrate into the skin: transcellular, intercellular, and follicular. The transfollicular path has been largely ignored because hair follicles constitute only 0.1% of the total skin. The hair follicle is a skin appendage with a complex structure containing many cell types that produce highly specialised proteins. The hair follicle is in a continuous cycle: anagen is the hair growth phase, catagen the involution phase and telogen is the resting phase. Nonetheless, the hair follicle has great potential for skin treatment, owing to its deep extension into the dermis and thus provides much deeper penetration and absorption of compounds beneath the skin than seen with the transdermal route. In the case of skin diseases and of cosmetic products, delivery to sweat glands or to the pilosebaceous unit is essential for the effectiveness of the drug. Increased accumulation in the pilosebaceous unit could treat alopecia, acne and skin cancer more efficiently and improve the effect of cosmetic substances and nutrients. Therefore, we review herein various drug delivery systems, including liposomes, niosomes, microspheres, nanoparticles, nanoemulsions, lipid nanocarriers, gene therapy and discuss the results of recent researches. We also review the drugs which have been investigated for pilosebaceous delivery.

  10. Chain Routing: A new routing framework for the Internet based on complete orders

    CERN Document Server

    Arjona-Villicaña, P David; Stepanenko, Alexander S

    2009-01-01

    A new framework to perform routing at the Autonomous System level is proposed in this paper. This mechanism, called Chain Routing, uses complete orders as its main topological unit, which enables a group of Autonomous Systems to define an acyclic structure to route packets to a destination. The employment of complete orders also allows easy identification and avoidance of persistent route oscillations, eliminates the possibility of developing transient loops in paths, and provides a structure that facilitates the implementation of traffic engineering. Moreover, by combining Chain Routing with other mechanisms that implement complete orders in time, we surmise it is possible to design a new routing protocol which could be more reliable and stable than BGP. Although Chain Routing will require an increase of the message overhead and greater coordination between network administrators, the rewards in stability and resilience should more than compensate for this effort.

  11. Routing problems based on hils system platform

    Directory of Open Access Journals (Sweden)

    Andrzej Adamski

    2015-03-01

    Full Text Available Background: The logistic systems are very complex socio-technical systems. In this paper the proposal of application of the hierarchical multi-layers system platform HILS approach for the solution of the complex vehicle routing problems is presented. The interactive system functional structure was proposed which by intelligent dedicated inter-layers interactions enables the professional solutions of these practical problems. To illustrate these capabilities the complex example of the real-time VRP-SPD-TW routing problem was presented in which upper layers offers the context-related real-time updating network specifications that stimulates the adequate routing parameters and specifications updating for problem solution in optimization layer. At the bottom dispatching control layer the DISCON (Dispatching CONtrol method from public transport was adopted to logistics applications in which the actual routing is treated as obligatory reference schedule to be stabilized. The intelligence aspects are related among others to HILS based decomposition, context-related trade-offs between routing modifications and corrective dispatching control capabilities e.g. priority or route guidance actions. Methods: Decomposition of the vehicle routing problem for the HILS layers tasks creating the ILS system hierarchical structure. Dedicated solution method for the VRP-SPD-TW routing problem. The recognition of the control preferences structure by AHP-Entropy methods. DISCON and PIACON multi-criteria interacting control methods. Results: Original formulation and solution of the vehicle routing problem by system-wide approach with essential practical advantages: consistency, lack of redundancy, essential reduction of dimension, dedicated formulation, multi-criteria approach, exploration of the integration and intelligence features supported by the intelligent PIACON-DISCON methods control activities Conclusions: The presented proposal creates the professional

  12. Steganographic Routing in Multi Agent System Environment

    CERN Document Server

    Szczypiorski, Krzysztof; Mazurczyk, Wojciech

    2008-01-01

    In this paper we present an idea of trusted communication platform for Multi-Agent Systems (MAS) called TrustMAS. Based on analysis of routing protocols suitable for MAS we have designed a new proactive hidden routing. Proposed steg-agents discovery procedure, as well as further routes updates and hidden communication, are cryptographically independent. Steganographic exchange can cover heterogeneous and geographically outlying environments using available cross-layer covert channels. Finally we have specified rules that agents have to follow to benefit the TrustMAS distributed router platform.

  13. Traffic Performance Analysis of Manet Routing Protocol

    CERN Document Server

    Rajeswari, S; 10.5121/ijdps.2011.2306

    2011-01-01

    The primary objective of this research work is to study and investigate the performance measures of Gossip Routing protocol and Energy Efficient and Reliable Adaptive Gossip routing protocols. We use TCP and CBR based traffic models to analyze the performance of above mentioned protocols based on the parameters of Packet Delivery Ratio, Average End-to-End Delay and Throughput. We will investigate the effect of change in the simulation time and Number of nodes for the MANET routing protocols. For Simulation, we have used ns-2 simulator.

  14. On line routing per mobile phone

    DEFF Research Database (Denmark)

    Bieding, Thomas; Görtz, Simon; Klose, Andreas

    2009-01-01

    . Additionally it is of utmost importance that the employed communication system is suitable integrated with the firm’s enterprise application system and business processes. On basis of a case study, we describe in this paper a system that is cheap and easy to implement due to the use of simple mobile phones......On-line routing is concerned with building vehicle routes in an ongoing fashion in such a way that customer requests arriving dynamically in time are efficiently and effectively served. An indispensable prerequisite for applying on-line routing methods is mobile communication technology...

  15. Analysis of Enhanced Associativity Based Routing Protocol

    Directory of Open Access Journals (Sweden)

    Said A. Shaar

    2006-01-01

    Full Text Available This study introduces an analysis to the performance of the Enhanced Associativity Based Routing protocol (EABR based on two factors; Operation complexity (OC and Communication Complexity (CC. OC can be defined as the number of steps required in performing a protocol operation, while CC can be defined as the number of messages exchanged in performing a protocol operation[1]. The values represent the worst-case analysis. The EABR has been analyzed based on CC and OC and the results have been compared with another routing technique called ABR. The results have shown that EABR can perform better than ABR in many circumstances during the route reconstruction.

  16. Pheromone Static Routing Strategy for Complex Networks

    CERN Document Server

    Ling, Xiang; Jiang, Rui; Hu, Mao-Bin

    2011-01-01

    In this paper, we adopt the concept of pheromone to generate a set of static paths that can reach the performance of global dynamic routing strategy [Phys. Rev. E 81, 016113(2010)]. In the test stage, pheromone is dropped to the nodes by packets forwarded by the global dynamic routing strategy. After that, static paths are generated according to the density of pheromone. The output paths can greatly improve traffic systems' overall capacity on different network structures, including scale-free networks, small-world networks and random graphs. Because the paths are static, the system needs much less computational resource than the global dynamic routing strategy.

  17. Multimedia Traffic Routing in Multilayer WDM Networks

    CERN Document Server

    Amphawan, Angela; Hasan, Hassanuddin

    2012-01-01

    The advent of real-time multimedia services over the Internet has stimulated new technologies for expanding the information carrying capacity of optical network backbones. Multilayer wavelength division multiplexing (WDM) packet switching is an emerging technology for increasing the bandwidth of optical networks. Two algorithms for the routing of the multimedia traffic flows were applied: (i) Capacitated Shortest Path First (CSPF) routing, which minimizes the distance of each flow linking the given source and destination nodes and satisfying capacity constraints; and (ii) Flow Deviation Algorithm (FDA) routing, which minimizes the network?wide average packet delay.

  18. Stability Analysis of Path-vector Routing

    CERN Document Server

    Dimitri, Papadimitriou

    2012-01-01

    Most studies on path-vector routing stability have been conducted empirically by means of ad-hoc analysis of BGP data traces. None of them consider prior specification of an analytic method including the use of stability measurement metrics for the systematic analysis of BGP traces and associated meta-processing for determining the local state of the routing system. In this paper, we define a set of metrics that characterize the local stability properties of path-vector routing such as BGP (Border Gateway Protocol). By means of these stability metrics, we propose a method to analyze the effects of BGP policy- and protocol-induced instability on local routers.

  19. Analysis of Path-vector Routing Stability

    CERN Document Server

    Dimitri, Papadimitriou

    2012-01-01

    Most studies on path-vector routing stability have been conducted empirically by means of ad-hoc analysis of BGP data traces. None of them consider prior specification of an analytic method including the use of stability measurement metrics for the systematic analysis of BGP traces and associated meta-processing for determining the local state of the routing system. In this paper, we define a set of metrics that characterize the local stability properties of path-vector routing such as BGP (Border Gateway Protocol). By means of these stability metrics, we propose a method to analyze the effects of BGP policy- and protocol-induced instability on local routers.

  20. Performance Analysis of Route Discovery by Cross Layer Routing Protocol- RDCLRP

    Directory of Open Access Journals (Sweden)

    Mehajabeen Fatima

    2013-06-01

    Full Text Available Wired and wireless network is based on the TCP / IP architecture but it is not sufficient to cope with the dynamics of the MANET. Cross layer design can be an alternative architecture for MANET. Frequent route break is one of the major problems of mobile adhoc network (MANET. Path breaks due to less available battery power and mobility of nodes. Most of the battery power is consumed in flooding of control packets. A key challenge in the design of efficient routing protocol is to reduce link breakage and flooding of control packets. Route breakage can be reduced if the possibility of route breakage is predicted and a handoff is done without drop of data packets. If route breakage is reduced, the more battery power will be available with nodes. In turn it reduces the possibility of route breakage and the possibility of flooding. This is a cumulative effect. So a novel preemptive route repair algorithm is proposed named as RDCLRP- Route discovery by cross layer routing protocol to reduce frequency of control packet flooding and route breakage. Three variants of RDCLRP and their results are illustrated. In this paper, the impact of the number of nodes on performance of RDCLRP are investigated and analyzed. The results show 55.6% reduction in link breakage, 14.7% improvement in residual battery power and an average of 6.7% increase in throughput compared to basic AODV.

  1. A SURVEY ON THE ALGORITHMIC APPROACH USED IN ROUTING FOR PLACEMENT AND ROUTING FLOW

    Directory of Open Access Journals (Sweden)

    KOMAL

    2014-06-01

    Full Text Available Routing is one of the long-drawn-out processes after placement in VLSI design. The routing provides the path for nets on chip to interconnect the pins on the pads or blocks at the chip boundary. This paper provides a systematic insight of interconnect of nets in ‘Placement and Routing Flow’ based on various methods (global routing and detailed routing. Further, the work reported so far has been compared with a multiple techniques for multiple factors such as reduction in wire-length, short execution time, fast and accurate congestion, improvement in complexity, signal integrity and crosstalk. Here the methodologies adopts are the Routing congestion estimator algorithm, Ant Colony Optimization. Firefly Algorithm, Monotonic Staircase Routing and so on. It is also observed that Pattern Based Routing is much faster than the Maze Routing, and the improved parameters are there is no over-congestion and 100% routablity with Monotonic Staircase Channels. zero overflow by Simulated-Evolution(Sim-E, and Complexity improved by a Fuzzified Approach Towards Global Routing.

  2. Novel Routing Protocol Based on Periodic Route Discovery for Mobile Adhoc Networks

    Directory of Open Access Journals (Sweden)

    V.Jai KumarAssociate

    2016-12-01

    Full Text Available A group of mobile devices called as nodes, without any centralized network, communicates with each other over multi-hop links is called as an Ad-hoc Network (MANET. The military battle-field scenarios, Post-disaster rescue efforts, sensor networks, and entrepreneurs in a conference are some of the examples of mobile ad-hoc networks. Since there is no infrastructure in the network, the routing should be handled at every node. To improve the life time of network different routing protocols are consider. In present routing protocols of ad hoc networks, routing is an act of moving information from a source to destination in an internetwork. Route is selected in the route discovery phase until all the packets are sent out. Due to the continuous flow of packets in a selected route leads to the route failure. In order to reduce this problem we consider PRD-based MMBCR and considering the percentage of the optimum value for periodic route discovery. In our research we are going to analyze the performance of different routing protocols like DSR, MMBCR to get maximum optimum value using Network Simulator Software.

  3. VANET Routing Replay Attack Detection Research Based on SVM

    OpenAIRE

    Fan Qing Gang; Wang Li; Cai Yan Ning; Li Yong Qiang; Chen Jing

    2016-01-01

    In the process of establishing routing in VANET, because of the interference of routing request (RREQ) and routing response (RREP), the nodes in the network are busy with looking for routing or establishing routing. The impact on the network performance is extremely serious, such as increasing a lot of network overhead, consuming valuable bandwidth resources. In this paper, the influence of routing replay attack in VANET is studied. Four typical characteristic are extracted by “cross layer” s...

  4. An Enhanced Route Recovery Protocol for Mobile Ad Hoc Networks

    Science.gov (United States)

    Kim, Sangkyung; Park, Noyeul; Kim, Changhwa; Choi, Seung-Sik

    In case of link failures, many ad hoc routing protocols recover a route by employing source-initiated route re-discovery, but this approach can degrade system performance. Some use localized route recovery, which may yield non-optimal paths. Our proposal provides a mechanism that can enhance the overall routing performance by initiating route recovery at the destination node. We elucidate the effects through simulations including comparisons with AODV and AODV with local repair.

  5. Modify AODV Routing Protocol to Improve Motorway Surveillance System Performance

    OpenAIRE

    Layth Abdulkareem Hassnawi; R. Badlishah Ahmad; Abid Yahya

    2012-01-01

    This paper presents an algorithm to modify the Ad Hoc On-Demand Distance Vector (AODV) routing protocol in order to improve the routing performance in motorway surveillance systems. The proposed protocol has all the characteristics of the original AODV routing protocol since it follows all the steps of the route discovery and route maintenance mechanism of the original AODV routing protocol. The Modified AODV (MAODV) is different from the original AODV protocol in that it modifies the origina...

  6. Performance Evaluation of MANET Routing Protocols

    Directory of Open Access Journals (Sweden)

    Hrituparna Paul

    2012-07-01

    Full Text Available The task of finding and sustaining routes in Mobile Ad-hoc Networks (MANETS is an important factor in determining the efficiency of any MANET protocol. MANET characteristically is an autonomous system of mobile nodes connected by wireless links without any centralised infrastructure. Absence of fixed infrastructures and host mobility thus network may experience rapid and unpredictable topology changes. Hence, routing is required in order to perform communication among the entire network. There are several routing protocols namely proactive, reactive and hybrid etc. In this paper we will discuss the active research work on these routing protocols and its performance evaluation. To this end, we adopt a simulation approach, which is more suitable to this kind of analysis

  7. IPv6 Network Mobility Route Optimization Survey

    Directory of Open Access Journals (Sweden)

    Samer S. Hassan

    2011-01-01

    Full Text Available Problem statement: This study describes that the Next Generation of Networks (NGN communication will supports multiple technologies, handles the mobility of end users to move through heterogeneous access networks, with ability to connect to different networks. Where the Internet Engineer Task Force maintain (IETF the Mobile IPv6 (MIPv6 to handles the mobility of networks (NEMO, to provide wide band and more scalable network services. One of the MIPv6 built-in features is Route Optimization (RO to solve the inefficient route problem. Conclusion/Recommendations: The main objective of this article is to survey, classify and make a compression between the available schemes for route optimization over the last years depends on the basic criteria generated from the published articles within different network topology. This article presents the problem of suboptimal route which is further increased with increasing of nesting levels and there is no such one scheme is perfect for all network environments.

  8. Pharmacokinetics of Alternative Administration Routes of Melatonin

    DEFF Research Database (Denmark)

    Zetner, D; Andersen, L P H; Rosenberg, J

    2016-01-01

    BACKGROUND: Melatonin is traditionally administered orally but has a poor and variable bioavailability. This study aims to present an overview of studies investigating the pharmacokinetics of alternative administration routes of melatonin. METHODS: A systematic literature search was performed...... and included experimental or clinical studies, investigating pharmacokinetics of alternative administration routes of melatonin in vivo. Alternative administration routes were defined as all administration routes except oral and intravenous. RESULTS: 10 studies were included in the review. Intranasal...... administration exhibited a quick absorption rate and high bioavailability. Transdermal administration displayed a variable absorption rate and possible deposition of melatonin in the skin. Oral transmucosal administration of melatonin exhibited a high plasma concentration compared to oral administration...

  9. Language and Spatial Cognition in Route Navigation

    Institute of Scientific and Technical Information of China (English)

    宋娟

    2013-01-01

    The purpose of this study is to investigate the contrast between using street names or landmarks to process spatial in⁃structions. The study confirms the special cognitive status of landmarks in the mental representation of routes.

  10. Integrating routing decisions in public transportation problems

    CERN Document Server

    Schmidt, Marie E

    2014-01-01

    This book treats three planning problems arising in public railway transportation planning: line planning, timetabling, and delay management, with the objective to minimize passengers’ travel time. While many optimization approaches simplify these problems by assuming that passengers’ route choice is independent of the solution, this book focuses on models which take into account that passengers will adapt their travel route to the implemented planning solution. That is, a planning solution and passengers’ routes are determined and evaluated simultaneously. This work is technically deep, with insightful findings regarding complexity and algorithmic approaches to public transportation problems with integrated passenger routing. It is intended for researchers in the fields of mathematics, computer science, or operations research, working in the field of public transportation from an optimization standpoint. It is also ideal for students who want to gain intuition and experience in doing complexity proofs ...

  11. Multicriteria Evolutionary Weather Routing Algorithm in Practice

    Directory of Open Access Journals (Sweden)

    Joanna Szlapczynska

    2013-03-01

    Full Text Available The Multicriteria Evolutionary Weather Routing Algorithm (MEWRA has already been introduced by the author on earlier TransNav 2009 and 2011 conferences with a focus on theoretical application to a hybrid-propulsion or motor-driven ship. This paper addresses the topic of possible practical weather routing applications of MEWRA. In the paper some practical advantages of utilizing Pareto front as a result of multicriteria optimization in case of route finding are described. The paper describes the notion of Pareto-optimality of routes along with a simplified, easy to follow, example. It also discusses a choice of the most suitable ranking method for MEWRA (a comparison between Fuzzy TOPSIS and Zero Unitarization Method is presented. In addition to that the paper briefly outlines a commercial application of MEWRA.

  12. Recommended Cross-Desert Driving Route

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Beijing - Duolun - Dalai Nur- Hexigten Banner -Saihanba - Weichang - Luanping - Miyun - Beijing. Along this 1,600-kilometer route is a 150-kin section(between Duolun and Darhan) of desert with no surfaced road - a paradise for desert drivers.

  13. A new routing assignment model for Internet

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper builds a new traffic assignment model for Internet. The routing policy based on this model can realize load splitting in a network automatically, which overcomes the shortcoming of OSPF and satisfies the load balancing requirement of IETF.

  14. Latent factors and route choice behaviour

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo

    . A reliable dataset was prepared through measures of internal consistency and sampling adequacy, and data were analyzed with a proper application of factor analysis to the route choice context. For the dataset obtained from the survey, six latent constructs affecting driver behaviour were extracted and scores...... by proposing a methodology for collecting and analyzing behavioural indicators and modelling route choices of individuals driving habitually from home to their workplace. A web-based survey was designed to collect attitudinal data and observed route choices among faculty and staff members of Turin Polytechnic...... on each factor for each survey participant were calculated. Path generation algorithms were examined with respect to observed behaviour, through a measure of reproduction with deterministic techniques of the routes indicated in the answers to the survey. Results presented evidence that the majority...

  15. Rich Vehicle Routing Problems and Applications

    DEFF Research Database (Denmark)

    Wen, Min

    the company’s solution in terms of all the objectives, including the travel time, customer waiting and daily workload balances, under the given constraints considered in the work. Finally, we address an integrated vehicle routing and driver scheduling problem, in which a large number of practical constraints......The Vehicle Routing Problem (VRP) is one of the most important and challenging optimization problems in the field of Operations Research. It was introduced by Dantzig and Ramser (1959) and defined as the problem of designing the optimal set of routes for a fleet of vehicles in order to serve...... given to various extensions of the VRP that arise in real life. These extensions are often called Rich Vehicle Routing Problems (RVRPs). In contrast to the research of classical VRP that focuses on the idealized models with unrealistic assumptions, the research of RVRPs considers those complicated...

  16. Dams and Obstructions along Iowa's Canoe Routes

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This dataset represents obstruction to canoe and boat users of the canoe routes of Iowa. This may represent actual dams, rock dams (natural or man made), large...

  17. Quantum chemistry-assisted synthesis route development

    Energy Technology Data Exchange (ETDEWEB)

    Hori, Kenji; Sumimoto, Michinori [Graduate School of Science and Engineering, Yamaguchi University, Tokiwadai, Ube, Yamaguchi 755-8611 (Japan); Murafuji, Toshihiro [Graduate School of Medicine, Yamaguchi University, Yamaguchi, Yamaguchi 753-8512 (Japan)

    2015-12-31

    We have been investigating “quantum chemistry-assisted synthesis route development” using in silico screenings and applied the method to several targets. Another example was conducted to develop synthesis routes for a urea derivative, namely 1-(4-(trifluoromethyl)-2-oxo-2H-chromen-7-yl)urea. While five synthesis routes were examined, only three routes passed the second in silico screening. Among them, the reaction of 7-amino-4-(trifluoromethyl)-2H-chromen-2-one and O-methyl carbamate with BF{sub 3} as an additive was ranked as the first choice for synthetic work. We were able to experimentally obtain the target compound even though its yield was as low as 21 %. The theoretical result was thus consistent with that observed. The summary of transition state data base (TSDB) is also provided. TSDB is the key to reducing time of in silico screenings.

  18. Latent variables and route choice behavior

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo; Bekhor, Shlomo; Pronello, Cristina

    2012-01-01

    In the last decade, a broad array of disciplines has shown a general interest in enhancing discrete choice models by considering the incorporation of psychological factors affecting decision making. This paper provides insight into the comprehension of the determinants of route choice behavior by...... results illustrate that considering latent variables (i.e., memory, habit, familiarity, spatial ability, time saving skills) alongside traditional variables (e.g., travel time, distance, congestion level) enriches the comprehension of route choice behavior....

  19. A CONTRIBUTION TO SECURE THE ROUTING PROTOCOL

    Directory of Open Access Journals (Sweden)

    Mohammed ERRITALI

    2011-10-01

    Full Text Available This work presents a contribution to secure the routing protocol GPSR (Greedy Perimeter StatelessRouting for vehicular ad hoc networks, we examine the possible attacks against GPSR and securitysolutions proposed by different research teams working on ad hoc network security. Then, we propose asolution to secure GPSR packet by adding a digital signature based on symmetric cryptographygenerated using the AES algorithm and the MD5 hash function more suited to a mobile environment

  20. Energy Efficient Routing in Nomadic Networks

    DEFF Research Database (Denmark)

    Kristensen, Mads Darø; Bouvin, Niels Olof

    2007-01-01

    We present an evaluation of a novel energy-efficient routing protocol for mobile ad-hoc networks. We combine two techniques for optimizing energy levels with a well-known routing protocol. We examine the behavior of this combination in a nomadic network setting, where some nodes are stationary...... and have a steady power supply. Protocol optimizations for the nomadic scenario are presented and validated through simulations...

  1. Light olefins - challenges from new production routes?

    Energy Technology Data Exchange (ETDEWEB)

    Zimmermann, H. [Linde Engineering, Pullach (Germany)

    2007-07-01

    Light Olefins are the building blocks for many modern plastic products and are produced in large quantities. Driven by high crude oil prices, production is shifted to regions with low cost raw materials. Alternatives to the traditional production from Naphta, AGO and other crude products are becoming attractive. This paper evaluates several methods Ethylene and Pro-pylene production economically and also the regional advantageous routes. The analysis includes Steamcracking, dehydrogenation, dehydration of Ethanol, Methanol based routes and olefin conversion by Metathesis. (orig.)

  2. Ultrafast single-shot imaging of laser-produced plasmas via spatial division and routing

    Science.gov (United States)

    Yeola, Sarang; Kuk, Donghoon; Kim, Ki-Yong

    2017-01-01

    We have developed a single-shot imaging camera, which can capture ultrafast events occurring on femtosecond and picosecond time scales. The working principle of this camera relies on spatial division and routing of femtosecond laser pulses. Here we have employed simple optics such as mirrors to produce multiple, time-delayed laser pulses and to project time-evolving images onto separate standard cameras. This spatial division and routing method has been tested with a femtosecond amplified laser in visualizing the evolution of laser-induced ionization in air and ablation in solids in single-shots. The number of frames is currently limited to 4 but can be increased further to N x N by using 3D printed optics for spatial division and routing. Work supported by the National Science Foundation (NSF) under Award No. 1351455.

  3. The Green Ship Routing and Scheduling Problem (GSRSP): A conceptual approach

    DEFF Research Database (Denmark)

    Kontovas, Christos A.

    2014-01-01

    Recent reviews of the literature on ship routing and scheduling note the increased attention to environmental issues. This is an area of paramount importance for international shipping and will be even more so in the future. This short communication is motivated by the increasing attention...... to 'green' routing and scheduling and outlines some possible ways to incorporate the air emissions dimension into maritime transportation OR. The main contribution of this note vis-a-vis the state of the art is that it conceptualizes the formulation of the 'Green Ship Routing and Scheduling Problem' (GSRSP......) based on existing formulations and highlights all the important parameters of the problem. (C) 2014 Elsevier Ltd. All rights reserved....

  4. Hydrothermal Treatment of Tannin: A Route to Porous Metal Oxides and Metal/Carbon Hybrid Materials

    Directory of Open Access Journals (Sweden)

    Flavia L. Braghiroli

    2017-01-01

    Full Text Available In the present paper, porous materials were prepared from the hydrothermal treatment of aqueous solutions of tannin, a renewable phenolic resource extracted from tree barks, containing dissolved salts of transition metals: V, Cr, Ni and Fe. Hydrothermal treatment produced carbonaceous particles doped with the aforementioned metals, and such materials were treated according to two different routes: (i calcination in air in order to burn the carbon and to recover porous oxides; (ii pyrolysis in inert atmosphere so as to recover porous metal/carbon hybrid materials. The nature of the metal salt was found to have a dramatic impact on the structure of the materials recovered by the first route, leading either to nano-powders (V, Cr or to hollow microspheres (Ni, Fe. The second route was only investigated with iron, leading to magnetic Fe-loaded micro/mesoporous carbons whose texture, pore volumes and surface areas gradually changed with the iron content.

  5. Improved Multispanning Tree Routing Using Efficient and Reliable Routing Algorithm for Irregular Networks

    Directory of Open Access Journals (Sweden)

    L. Keerthana

    2012-06-01

    Full Text Available A Strategy of Multispanning Tree Zone Ordered Label Based routing is improved with Efficient and Reliable (EAR routing for irregular networks is presented and analyzed in this work. Most existing deadlock free routing methods for irregular topologies impose several limitations on node and channel labeling in an irregular network is based on a pre-defined spanning tree.It is not possible to form a deadlock free zone of three or four channel labels for two spanning tree. So this existing Multispanning Tree Zone Ordered Label Based routing is modified with Efficient and Reliable (EAR routing. EAR is based on four parameters length of the path,distance traversed,transmission of link and energy levels to dynamically determine and maintain the best routes.. The simulation results have shown highest packet delivery ratio, minimum latency, and energy consumption.

  6. Genetic algorithm to solve constrained routing problem with applications for cruise missile routing

    Science.gov (United States)

    Latourell, James L.; Wallet, Bradley C.; Copeland, Bruce

    1998-03-01

    In this paper the use of a Genetic Algorithm to solve a constrained vehicle routing problem is explored. The problem is two-dimensional with obstacles represented as ellipses of uncertainty surrounding each obstacle point. A route is defined as a series of points through which the vehicle sequentially travels from the starting point to the ending point. The physical constraints of total route length and maximum turn angle are included and appear in the fitness function. In order to be valid, a route must go from start to finish without violating any constraint. The effects that different mutation rates and population sizes have on the algorithm's computation speed and ability to find a high quality route are also explored. Finally, possible applications of this algorithm to the problem of route planning for cruise missiles are discussed.

  7. Manet Load Balancing Parallel Routing Protocol

    Directory of Open Access Journals (Sweden)

    Hesham Arafat Ali

    2012-07-01

    Full Text Available In recent years, multi-path routing protocols have attained more attention in mobile ad hoc networks as compared to other routing schemes due to their abilities and efficiency in improving bandwidth of communication, increasing delivery reliability, responding to congestion and heavy traffic. Several protocols have been developed to address multi path routing, but it always has a problem that the discovered paths may be not 100% disjoint and sending data is done in only one path until it's broken; the discovery of multiple paths also generates more overhead on the network. Load Balancing Parallel Routing Protocol [LBPRP] tried to solve previous multi path problems, distributing traffic among multiple paths sending data in parallel form as it uses all paths in the same time. We employed a simple test scenario to be sure of proposed model efficiency and to validate the proposed Load Balancing Parallel Routing Protocol. [LBPRP] will achieve load balancing in sending data, decreasing the end-to-end delay and increasing the packet delivery ratio and throughput, thus the performance of multi-path routing protocols can be improved consequently.

  8. Survivable Lightpath Routing in WDM Optical Networks

    Institute of Scientific and Technical Information of China (English)

    LIUFengqing; ZENGQingji; ZHUXu; YANGXudong; XIAOShilin

    2004-01-01

    In IP over WDM networks, when a failure(such as a fiber cut) occurs, the service restoration can be implemented by dynamic routing in IP layer. But it needs that the logical topology remains connected after any physical link failure. Otherwise, IP layer cannot find an alternate path to restore the service. The problem of routing logical links (lightpaths) on a physical network topology in a way that the logical topology remains connected in the event of single physical link failure is called survivabl erouting. In this paper~ we address the survivable routing problem by proposing a new ILP algorithm that works well with sparse-connected logical topologies. The necessary and sufficient conditions for survivable routing are simplified, which greatly reduces the number of survivable constraints. Based-on the simplified conditions, a new ILP formulation with K-shortest paths as alternate paths for a logical link is presented, which mainly reduces the number of ILP variables. Finally, numerical results are given and discussed to show that most survivable routing solutions can be found with our algorithms, and the time needed to find such a survivable routing solution is much smaller than other similar methods.

  9. ACO Agent Based Routing in AOMDV Environment

    Directory of Open Access Journals (Sweden)

    Kaur Amanpreet

    2016-01-01

    Full Text Available Mobile Ad-hoc Network (MANET is a group of moving nodes which can communicate with each other without the help of any central stationary node. All the nodes in the MANET act as router for forwarding data packets. The nodes in the network also move randomly and there exists no fixed infrastructure. So, path breaks are the frequent problem in MANET. The routing protocol faces a lot of problem due these path breaks. Therefore, the routing protocol which is multipath in nature is more reliable than a unipath routing protocol. Ant colony optimization is a relatively new technique which is suitable for the optimization problems. AOMDV is a multipath routing protocol. Thus, if there happens to be path break, the packets can start following the new path which has already been selected. In this paper, we are trying to add ant’s agents into AOMDV behavior. In this way, the new protocol will be benefited by the dual properties i.e. of ant’s nature and multipath nature of AOMDV. The modified concept is simulated and the outcomes are compared with AOMDV, AODV and DSR routing protocols for few performance parameters. Results obtained are encouraging; the new algorithm performs better than traditional unipath and multipath routing protocols.

  10. Pseudo-Cycle-Based Multicast Routing in Wormhole-Routed Networks

    Institute of Scientific and Technical Information of China (English)

    SONG JianPing (宋建平); HOU ZiFeng (侯紫峰); XU Ming (许铭)

    2003-01-01

    This paper addresses the problem of fault-tolerant multicast routing in wormholerouted multicomputers. A new pseudo-cycle-based routing method is presented for constructing deadlock-free multicast routing algorithms. With at most two virtual channels this technique can be applied to any connected networks with arbitrary topologies. Simulation results show that this technique results in negligible performance degradation even in the presence of a large number of faulty nodes.

  11. Deflection routing in slotted self-routing networks with arbitrary topology

    OpenAIRE

    2002-01-01

    A deflection routing algorithm that can be applied to a novel self-routing address scheme for networks with arbitrary topology is proposed. The proposed deflection routing algorithm can be implemented all-optically using bitwise optical logic gates. Besides the primary output link selection, alternate output link choices by a packet at each node in case of deflection are also encoded in the address header. Priority classes can also be defined in the proposed address scheme. The performance of...

  12. Region Based Route Planning: Multi-Abstraction Route Planning Based On Intermediate Level Vision Processing

    Science.gov (United States)

    Doshi, Rajkumar S.; Lam, Raymond; White, James E.

    1989-01-01

    The Region Based Route Planner performs intermediate-level and high-level processing on vision data to organize the image into more meaningful higher-level topological representations. A variety of representations are employed at appropriate stages in the route plan-ning process. A variety of abstractions are used for the purposes of problem reduction and application of multiple criteria at different phases during the navigation planning process. The Region Based Route Planner operates in terrain scenarios where some or most of the terrain is occluded. The Region Based Route Planner operates without any priori maps. The route planner uses two dimensional representations and utilizes gradient and roughness information. The implementation described here is being tested on the JPL Robotic Vehicle. The Region Based Route Planner operates in two phases. In the first phase, the terrain map is segmented to derive global information about various features in it. The next phase is the actual route planning phase. The route is planned with increasing amounts of detail by successive refinement. This phase has three abstrac-tions. In the first abstraction, the planner analyses high level information and so a coarse, region-to-region plan is produced. The second abstraction produces a list of pairs of entry and exit waypoints for only these selected regions. In the last abstraction, for every pair of these waypoints, a local route planner is invoked. This planner finds a detailed point-to-point path by searching only within the boundaries of these relatively small regions.

  13. Evaluating environmental modeling and sampling data with biomarker data to identify sources and routes of exposure

    Science.gov (United States)

    Shin, Hyeong-Moo; McKone, Thomas E.; Bennett, Deborah H.

    2013-04-01

    Exposure to environmental chemicals results from multiple sources, environmental media, and exposure routes. Ideally, modeled exposures should be compared to biomonitoring data. This study compares the magnitude and variation of modeled polycyclic aromatic hydrocarbons (PAHs) exposures resulting from emissions to outdoor and indoor air and estimated exposure inferred from biomarker levels. Outdoor emissions result in both inhalation and food-based exposures. We modeled PAH intake doses using U.S. EPA's 2002 National Air Toxics Assessment (NATA) county-level emissions data for outdoor inhalation, the CalTOX model for food ingestion (based on NATA emissions), and indoor air concentrations from field studies for indoor inhalation. We then compared the modeled intake with the measured urine levels of hydroxy-PAH metabolites from the 2001-2002 National Health and Nutrition Examination Survey (NHANES) survey as quantifiable human intake of PAH parent-compounds. Lognormal probability plots of modeled intakes and estimated intakes inferred from biomarkers suggest that a primary route of exposure to naphthalene, fluorene, and phenanthrene for the U.S. population is likely inhalation from indoor sources. For benzo(a)pyrene, the predominant exposure route is likely from food ingestion resulting from multi-pathway transport and bioaccumulation due to outdoor emissions. Multiple routes of exposure are important for pyrene. We also considered the sensitivity of the predicted exposure to the proportion of the total naphthalene production volume emitted to the indoor environment. The comparison of PAH biomarkers with exposure variability estimated from models and sample data for various exposure pathways supports that both indoor and outdoor models are needed to capture the sources and routes of exposure to environmental contaminants.

  14. 76 FR 17471 - Air Tour Management Plan Environmental Assessment for Mount Rainier National Park, WA; Public...

    Science.gov (United States)

    2011-03-29

    ... to the public which contain specific routes and altitudes used by air tour operators when providing... Federal Aviation Administration Air Tour Management Plan Environmental Assessment for Mount Rainier... availability of preliminary alternatives. SUMMARY: This notice announces the availability of draft air...

  15. Rating mass concentration of airborne dust in the road transport depending on the type of pollution transport routes.

    OpenAIRE

    PÁVEK, Miroslav

    2014-01-01

    In the thesis the values of air pollution re-suspended solid pollutants on the diameter of 10 micrometres (PM10) during the movement of vehicles of different categories of polluted roads routes. Measurements were carried out on three lines of transport operation of various vehicle categories as diverse weight and the type of pollution road. Measured values and analysis results show that the resulting air pollution in the vicinity of the road affects several factors. The main factors include t...

  16. Design and Evaluation of a Dynamic Programming Flight Routing Algorithm Using the Convective Weather Avoidance Model

    Science.gov (United States)

    Ng, Hok K.; Grabbe, Shon; Mukherjee, Avijit

    2010-01-01

    The optimization of traffic flows in congested airspace with varying convective weather is a challenging problem. One approach is to generate shortest routes between origins and destinations while meeting airspace capacity constraint in the presence of uncertainties, such as weather and airspace demand. This study focuses on development of an optimal flight path search algorithm that optimizes national airspace system throughput and efficiency in the presence of uncertainties. The algorithm is based on dynamic programming and utilizes the predicted probability that an aircraft will deviate around convective weather. It is shown that the running time of the algorithm increases linearly with the total number of links between all stages. The optimal routes minimize a combination of fuel cost and expected cost of route deviation due to convective weather. They are considered as alternatives to the set of coded departure routes which are predefined by FAA to reroute pre-departure flights around weather or air traffic constraints. A formula, which calculates predicted probability of deviation from a given flight path, is also derived. The predicted probability of deviation is calculated for all path candidates. Routes with the best probability are selected as optimal. The predicted probability of deviation serves as a computable measure of reliability in pre-departure rerouting. The algorithm can also be extended to automatically adjust its design parameters to satisfy the desired level of reliability.

  17. A UAV routing and sensor control optimization algorithm for target search

    Science.gov (United States)

    Collins, Gaemus E.; Riehl, James R.; Vegdahl, Philip S.

    2007-04-01

    An important problem in unmanned air vehicle (UAV) and UAV-mounted sensor control is the target search problem: locating target(s) in minimum time. Current methods solve the optimization of UAV routing control and sensor management independently. While this decoupled approach makes the target search problem computationally tractable, it is suboptimal. In this paper, we explore the target search and classification problems by formulating and solving a joint UAV routing and sensor control optimization problem. The routing problem is solved on a graph using receding horizon optimal control. The graph is dynamically adjusted based on the target probability distribution function (PDF). The objective function for the routing optimization is the solution of a sensor control optimization problem. An optimal sensor schedule (in the sense of maximizing the viewed target probability mass) is constructed for each candidate flight path in the routing control problem. The PDF of the target state is represented with a particle filter and an "occupancy map" for any undiscovered targets. The tradeoff between searching for undiscovered targets and locating tracks is handled automatically and dynamically by the use of an appropriate objective function. In particular, the objective function is based on the expected amount of target probability mass to be viewed.

  18. The cost of simplifying air travel when modeling disease spread.

    Directory of Open Access Journals (Sweden)

    Justin Lessler

    Full Text Available BACKGROUND: Air travel plays a key role in the spread of many pathogens. Modeling the long distance spread of infectious disease in these cases requires an air travel model. Highly detailed air transportation models can be over determined and computationally problematic. We compared the predictions of a simplified air transport model with those of a model of all routes and assessed the impact of differences on models of infectious disease. METHODOLOGY/PRINCIPAL FINDINGS: Using U.S. ticket data from 2007, we compared a simplified "pipe" model, in which individuals flow in and out of the air transport system based on the number of arrivals and departures from a given airport, to a fully saturated model where all routes are modeled individually. We also compared the pipe model to a "gravity" model where the probability of travel is scaled by physical distance; the gravity model did not differ significantly from the pipe model. The pipe model roughly approximated actual air travel, but tended to overestimate the number of trips between small airports and underestimate travel between major east and west coast airports. For most routes, the maximum number of false (or missed introductions of disease is small (<1 per day but for a few routes this rate is greatly underestimated by the pipe model. CONCLUSIONS/SIGNIFICANCE: If our interest is in large scale regional and national effects of disease, the simplified pipe model may be adequate. If we are interested in specific effects of interventions on particular air routes or the time for the disease to reach a particular location, a more complex point-to-point model will be more accurate. For many problems a hybrid model that independently models some frequently traveled routes may be the best choice. Regardless of the model used, the effect of simplifications and sensitivity to errors in parameter estimation should be analyzed.

  19. Allocation and Routing of CRAF MD80 Aircraft

    Science.gov (United States)

    1990-03-01

    5 II. Literature Review...................7 Formal Statement of the Vehicle Routing Problem ............ .. . .. .. ....... Vehicle...83 Appendix H: Example Vehicle Routing Problem Input 84 Appendix I: Example Vehicle Routing Problem Output 85 Appendix J: Spacefilling Curve...this problem is a stochastic vehicle routing problem with multiple depots. In this case, there are nine depots and 30 vehicles corresponding to nine

  20. Energy-Efficient Routing for Signal Detection in Wireless Sensor Networks

    Science.gov (United States)

    2009-06-01

    manuscript and ap­ proving it for publication was Dr. Mareelo G. S. Bruno, This materia ] is based on research supported by the Air Force Research...interest from a point in space, and we wish to find optimal routing which strives for a balance between the energy consumption and detection perfor­...given in (9) are called flow balance constraints which guarantee that, for all nodes on the path, ex­ cept the source and destination nodes, the

  1. Children's route choice during active transportation to school : difference between shortest and actual route

    NARCIS (Netherlands)

    Dessing, D.; Vries, S.I. (Sanne); Hegeman, G.; Mechelen, W. van; Pierik, F.H.

    2016-01-01

    Background: The purpose of this study is to increase our understanding of environmental correlates that are associated with route choice during active transportation to school (ATS) by comparing characteristics of actual walking and cycling routes between home and school with the shortest possible r

  2. Routes to Reading and Spelling: Testing the Predictions of Dual-Route Theory

    Science.gov (United States)

    Sheriston, Lee; Critten, Sarah; Jones, Emily

    2016-01-01

    Dual-route theory, which emphasizes the importance of lexical and nonlexical routes, makes specific predictions about the kinds of strategies that young students might adopt when attempting to correctly read and spell regular and irregular words. The current study tests these predictions by assessing strategy choice on regular, irregular, and…

  3. Automatic Extraction of Destinations, Origins and Route Parts from Human Generated Route Directions

    Science.gov (United States)

    Zhang, Xiao; Mitra, Prasenjit; Klippel, Alexander; Maceachren, Alan

    Researchers from the cognitive and spatial sciences are studying text descriptions of movement patterns in order to examine how humans communicate and understand spatial information. In particular, route directions offer a rich source of information on how cognitive systems conceptualize movement patterns by segmenting them into meaningful parts. Route directions are composed using a plethora of cognitive spatial organization principles: changing levels of granularity, hierarchical organization, incorporation of cognitively and perceptually salient elements, and so forth. Identifying such information in text documents automatically is crucial for enabling machine-understanding of human spatial language. The benefits are: a) creating opportunities for large-scale studies of human linguistic behavior; b) extracting and georeferencing salient entities (landmarks) that are used by human route direction providers; c) developing methods to translate route directions to sketches and maps; and d) enabling queries on large corpora of crawled/analyzed movement data. In this paper, we introduce our approach and implementations that bring us closer to the goal of automatically processing linguistic route directions. We report on research directed at one part of the larger problem, that is, extracting the three most critical parts of route directions and movement patterns in general: origin, destination, and route parts. We use machine-learning based algorithms to extract these parts of routes, including, for example, destination names and types. We prove the effectiveness of our approach in several experiments using hand-tagged corpora.

  4. Eccentricity in Zone Routing Protocol for MANET

    Directory of Open Access Journals (Sweden)

    Mrs Komal Nair

    2012-06-01

    Full Text Available A Mobile Ad-Hoc Network (MANET is a decentralized network of autonomous mobile nodes, able to communicate with each other over wireless links. Due to the mobility of the nodes, the topology ofthe network changes spontaneously, therefore use of conventional routing tables maintained at fixed points (routers is not suggested. Such a network may operate in a standalone fashion. There are variousrouting protocols available for MANETs. The most popular ones are DSR, DSDV and ZRP .The zone routing protocol (ZRP is a hybrid routing protocol that proactively maintains routes within a localregion of the network. ZRP can be configured for a particular network through adjustment of a single parameter, the routing zone radius. In this paper, we address the issue of configuring the ZRP to providethe best performance for a particular network at any time with the concept of eccentricity. The results illustrate the important characteristics of different protocols based on their performance and thus suggest some improvements in the respective protocol. The tools used for the simulation are NS2 which is the main simulator, NAM (Network Animator and Tracegraph which is used for preparing the graphs from the trace files.

  5. The Balanced Billing Cycle Vehicle Routing Problem

    Energy Technology Data Exchange (ETDEWEB)

    Groer, Christopher S [ORNL; Golden, Bruce [University of Maryland; Edward, Wasil [American University

    2009-01-01

    Utility companies typically send their meter readers out each day of the billing cycle in order to determine each customer s usage for the period. Customer churn requires the utility company to periodically remove some customer locations from its meter-reading routes. On the other hand, the addition of new customers and locations requires the utility company to add newstops to the existing routes. A utility that does not adjust its meter-reading routes over time can find itself with inefficient routes and, subsequently, higher meter-reading costs. Furthermore, the utility can end up with certain billing days that require substantially larger meter-reading resources than others. However, remedying this problem is not as simple as it may initially seem. Certain regulatory and customer service considerations can prevent the utility from shifting a customer s billing day by more than a few days in either direction. Thus, the problem of reducing the meterreading costs and balancing the workload can become quite difficult. We describe this Balanced Billing Cycle Vehicle Routing Problem in more detail and develop an algorithm for providing solutions to a slightly simplified version of the problem. Our algorithm uses a combination of heuristics and integer programming via a three-stage algorithm. We discuss the performance of our procedure on a real-world data set.

  6. Alternative routes to olefins. Chances and challenges

    Energy Technology Data Exchange (ETDEWEB)

    Meiswinkel, A.; Delhomme, C.; Ponceau, M. [Linde AG, Pullach (Germany)

    2013-11-01

    In the future, conventional raw materials which are used for the production of olefins will get shorter and more expensive and alternative raw materials and production routes will gain importance. Natural gas, coal, shale oil or bio-mass are potential sources for the production of olefins, especially ethylene and propylene, as major base chemicals. Several potential production routes were already developed in the past, but cost, energy and environmental considerations might make these unattractive or unfeasible in comparison to traditional processes (e.g. steam cracking). Other processes such as methanol to olefins processes were successfully developed and first commercial units are running. In addition, combination of traditional processes (e.g. coal/biomass gasification, Fischer-Tropsch and steam cracking) might enable new pathways. Besides, dehydration of ethanol is opening direct routes from biomass to 'green' ethylene. However, for these 'bio-routes', feedstock availability and potential land use conflict with food production (sugar cane, wheat,..) still need to be evaluated. finally, new oxidative routes, including processes such as oxidative coupling of methane or oxidative dehydrogenation, are still at an early development stage but present potential for future industrial applications. (orig.) (Published in summary form only)

  7. A Packet Routing Model for Computer Networks

    Directory of Open Access Journals (Sweden)

    O. Osunade

    2012-05-01

    Full Text Available The quest for reliable data transmission in today’s computer networks and internetworks forms the basis for which routing schemes need be improved upon. The persistent increase in the size of internetwork leads to a dwindling performance of the present routing algorithms which are meant to provide optimal path for forwarding packets from one network to the other. A mathematical and analytical routing model framework is proposed to address the routing needs to a substantial extent. The model provides schemes typical of packet sources, queuing system within a buffer, links and bandwidth allocation and time-based bandwidth generator in routing chunks of packets to their destinations. Principal to the choice of link are such design considerations as least-congested link in a set of links, normalized throughput, mean delay and mean waiting time and the priority of packets in a set of prioritized packets. These performance metrics were targeted and the resultant outcome is a fair, load-balanced network.

  8. An Indirect Route for Ethanol Production

    Energy Technology Data Exchange (ETDEWEB)

    Eggeman, T.; Verser, D.; Weber, E.

    2005-04-29

    The ZeaChem indirect method is a radically new approach to producing fuel ethanol from renewable resources. Sugar and syngas processing platforms are combined in a novel way that allows all fractions of biomass feedstocks (e.g. carbohydrates, lignins, etc.) to contribute their energy directly into the ethanol product via fermentation and hydrogen based chemical process technologies. The goals of this project were: (1) Collect engineering data necessary for scale-up of the indirect route for ethanol production, and (2) Produce process and economic models to guide the development effort. Both goals were successfully accomplished. The projected economics of the Base Case developed in this work are comparable to today's corn based ethanol technology. Sensitivity analysis shows that significant improvements in economics for the indirect route would result if a biomass feedstock rather that starch hydrolyzate were used as the carbohydrate source. The energy ratio, defined as the ratio of green energy produced divided by the amount of fossil energy consumed, is projected to be 3.11 to 12.32 for the indirect route depending upon the details of implementation. Conventional technology has an energy ratio of 1.34, thus the indirect route will have a significant environmental advantage over today's technology. Energy savings of 7.48 trillion Btu/yr will result when 100 MMgal/yr (neat) of ethanol capacity via the indirect route is placed on-line by the year 2010.

  9. Routing algorithms in networks-on-chip

    CERN Document Server

    Daneshtalab, Masoud

    2014-01-01

    This book provides a single-source reference to routing algorithms for Networks-on-Chip (NoCs), as well as in-depth discussions of advanced solutions applied to current and next generation, many core NoC-based Systems-on-Chip (SoCs). After a basic introduction to the NoC design paradigm and architectures, routing algorithms for NoC architectures are presented and discussed at all abstraction levels, from the algorithmic level to actual implementation.  Coverage emphasizes the role played by the routing algorithm and is organized around key problems affecting current and next generation, many-core SoCs. A selection of routing algorithms is included, specifically designed to address key issues faced by designers in the ultra-deep sub-micron (UDSM) era, including performance improvement, power, energy, and thermal issues, fault tolerance and reliability.   ·         Provides a comprehensive overview of routing algorithms for Networks-on-Chip and NoC-based, manycore systems; ·         Describe...

  10. ACRR: Ad Hoc On-Demand Distance Vector Routing with Controlled Route Requests

    CERN Document Server

    Kataria, Jayesh; Sanyal, Sugata

    2010-01-01

    Reactive routing protocols like Ad Hoc On-Demand Distance Vector Routing (AODV) and Dynamic Source Routing (DSR)in Ad-Hoc Wireless Networks which are used in Mobile and Ad Hoc Networks (MANETs) work by flooding the network with control packets. There is generally a limit on the number of these packets that can be generated or forwarded. But a malicious node can disregard this limit and flood the network with fake control packets. These packets hog the limited bandwidth and processing power of genuine nodes in the network while being forwarded. Due to this, genuine route requests suffer and many routes either do not get a chance to materialize or they end up being longer than otherwise. In this paper we propose a non cryptographic solution to the above problem and prove its efficiency by means of simulation.

  11. A Hybrid Routing Algorithm Based on Ant Colony and ZHLS Routing Protocol for MANET

    Science.gov (United States)

    Rafsanjani, Marjan Kuchaki; Asadinia, Sanaz; Pakzad, Farzaneh

    Mobile Ad hoc networks (MANETs) require dynamic routing schemes for adequate performance. This paper, presents a new routing algorithm for MANETs, which combines the idea of ant colony optimization with Zone-based Hierarchical Link State (ZHLS) protocol. Ant colony optimization (ACO) is a class of Swarm Intelligence (SI) algorithms. SI is the local interaction of many simple agents to achieve a global goal. SI is based on social insect for solving different types of problems. ACO algorithm uses mobile agents called ants to explore network. Ants help to find paths between two nodes in the network. Our algorithm is based on ants jump from one zone to the next zones which contains of the proactive routing within a zone and reactive routing between the zones. Our proposed algorithm improves the performance of the network such as delay, packet delivery ratio and overhead than traditional routing algorithms.

  12. Theory and New Primitives for Safely Connecting Routing Protocol Instances

    Science.gov (United States)

    2010-08-01

    reliability, and load. The current route redistribution procedure handles this incompatibility in a crude fashion. It resets the metric of a redis ...routing instances can also be performed in a link-state manner whereby one routing instance passes on its entire link state database to another...routers B and A, respectively. However, route redis - tribution at multiple points can easily result in routing anomalies [8]. Hence, to support

  13. Defining and Computing Alternative Routes in Road Networks

    CERN Document Server

    Dees, Jonathan; Sanders, Peter; Bader, Roland

    2010-01-01

    Every human likes choices. But today's fast route planning algorithms usually compute just a single route between source and target. There are beginnings to compute alternative routes, but this topic has not been studied thoroughly. Often, the aspect of meaningful alternative routes is neglected from a human point of view. We fill in this gap by suggesting mathematical definitions for such routes. As a second contribution we propose heuristics to compute them, as this is NP-hard in general.

  14. Comparison of Two Hierarchical Routing Protocols for Heterogeneous MANET

    Science.gov (United States)

    2007-10-01

    protocols (e.g. Ad-Hoc On-Demand Distance Vector routing protocol , AODV ) search for and maintain routes to destination nodes upon demand from...the time it takes to find a route when data needs to be sent. Protocols such as OLSR and AODV support nodes having multiple interfaces. However they...hierarchical ad hoc routing protocols are derived from a “flat” ad routing protocol . For instance, H- AODV [8] and H-DSR [11] are examples

  15. Evolution Strategies in the Multipoint Connections Routing

    Directory of Open Access Journals (Sweden)

    L. Krulikovska

    2010-09-01

    Full Text Available Routing of multipoint connections plays an important role in final cost and quality of a found connection. New algorithms with better results are still searched. In this paper, a possibility of using the evolution strategies (ES for routing is presented. Quality of found connection is evaluated from the view of final cost and time spent on a searching procedure. First, parametrical analysis of results of the ES are discussed and compared with the Prim’s algorithm, which was chosen as a representative of the deterministic routing algorithms. Second, ways for improving the ES are suggested and implemented. The obtained results are reviewed. The main improvements are specified and discussed in conclusion.

  16. Pheromone Static Routing Strategy for Complex Networks

    Science.gov (United States)

    Hu, Mao-Bin; Henry, Y. K. Lau; Ling, Xiang; Jiang, Rui

    2012-12-01

    We adopt the concept of using pheromones to generate a set of static paths that can reach the performance of global dynamic routing strategy [Phys. Rev. E 81 (2010) 016113]. The path generation method consists of two stages. In the first stage, a pheromone is dropped to the nodes by packets forwarded according to the global dynamic routing strategy. In the second stage, pheromone static paths are generated according to the pheromone density. The output paths can greatly improve traffic systems' overall capacity on different network structures, including scale-free networks, small-world networks and random graphs. Because the paths are static, the system needs much less computational resources than the global dynamic routing strategy.

  17. Genetic algorithms for the vehicle routing problem

    Science.gov (United States)

    Volna, Eva

    2016-06-01

    The Vehicle Routing Problem (VRP) is one of the most challenging combinatorial optimization tasks. This problem consists in designing the optimal set of routes for fleet of vehicles in order to serve a given set of customers. Evolutionary algorithms are general iterative algorithms for combinatorial optimization. These algorithms have been found to be very effective and robust in solving numerous problems from a wide range of application domains. This problem is known to be NP-hard; hence many heuristic procedures for its solution have been suggested. For such problems it is often desirable to obtain approximate solutions, so they can be found fast enough and are sufficiently accurate for the purpose. In this paper we have performed an experimental study that indicates the suitable use of genetic algorithms for the vehicle routing problem.

  18. Predication-Based Intelligence Routing on Telecommunications

    Institute of Scientific and Technical Information of China (English)

    DONGJun; HEJifeng; PANYunhe

    2004-01-01

    The routingtelecommunication networksbeing one of key issues of management influences the switch rate and load balance directly, and becomes more and more important as the telecommunication traffic increases at full speed. It was said that raising one percent of switch rate of current Chinese telecommunication networks would result in revenue about one billion Yuan RMB. On the basis of demerit-analysis of routing scheme being used, a new intelligent routing strategy based on multi-agent systems and recurrent neural network predication is presented, including routing strategy, Calls generating and agent~ recurrent neural network computation, simulation software design, results and discussion. The results show that the new one is better by virtue of its upstanding distribution and intelligence characters, and provides excellent solution to increase network switch rate and balance network load. Meanwhile, its applications will go beyond the scope of telecommunication networks. But whether the strategy will be perfect depends on the cooperation among operator, manufacturer and researchers.

  19. Generalized routing protocols for multihop relay networks

    KAUST Repository

    Khan, Fahd Ahmed

    2011-07-01

    Performance of multihop cooperative networks depends on the routing protocols employed. In this paper we propose the last-n-hop selection protocol, the dual path protocol, the forward-backward last-n-hop selection protocol and the forward-backward dual path protocol for the routing of data through multihop relay networks. The average symbol error probability performance of the schemes is analysed by simulations. It is shown that close to optimal performance can be achieved by using the last-n-hop selection protocol and its forward-backward variant. Furthermore we also compute the complexity of the protocols in terms of number of channel state information required and the number of comparisons required for routing the signal through the network. © 2011 IEEE.

  20. Trust Based Routing in Ad Hoc Network

    Science.gov (United States)

    Talati, Mikita V.; Valiveti, Sharada; Kotecha, K.

    Ad Hoc network often termed as an infrastructure-less, self- organized or spontaneous network.The execution and survival of an ad-hoc network is solely dependent upon the cooperative and trusting nature of its nodes. However, this naive dependency on intermediate nodes makes the ad-hoc network vulnerable to passive and active attacks by malicious nodes and cause inflict severe damage. A number of protocols have been developed to secure ad-hoc networks using cryptographic schemes, but all rely on the presence of trust authority. Due to mobility of nodes and limitation of resources in wireless network one interesting research area in MANET is routing. This paper offers various trust models and trust based routing protocols to improve the trustworthiness of the neighborhood.Thus it helps in selecting the most secure and trustworthy route from the available ones for the data transfer.

  1. Towards Building an Intelligent Call Routing System

    Directory of Open Access Journals (Sweden)

    Thien Khai Tran

    2016-01-01

    Full Text Available This paper presents EduICR - an Intelligent Call Routing system. This system can route calls to the most appropriate agent using routing rules built by the text classifier. EduICR includes the following main components: telephone communication network; Vietnamese speech recognition; Text classifier/ Natural language processor and Vietnamese speech synthesis. To our best knowledge, this is one of the first systems in Vietnam to implement the integration mechanism of text processing and speech processing. This allows voice applications to be more intelligent, able to communicate with humans in natural language with high accuracy and reasonable speed. Having been built and tested in real environment, our system proves its accuracy attaining more than 95%.

  2. Waste Collection Vehicle Routing Problem: Literature Review

    Directory of Open Access Journals (Sweden)

    Hui Han

    2015-08-01

    Full Text Available Waste generation is an issue which has caused wide public concern in modern societies, not only for the quantitative rise of the amount of waste generated, but also for the increasing complexity of some products and components. Waste collection is a highly relevant activity in the reverse logistics system and how to collect waste in an efficient way is an area that needs to be improved. This paper analyzes the major contribution about Waste Collection Vehicle Routing Problem (WCVRP in literature. Based on a classification of waste collection (residential, commercial and industrial, firstly the key findings for these three types of waste collection are presented. Therefore, according to the model (Node Routing Problems and Arc Routing problems used to represent WCVRP, different methods and techniques are analyzed in this paper to solve WCVRP. This paper attempts to serve as a roadmap of research literature produced in the field of WCVRP.

  3. Crosstalk-Aware Routing Resource Assignment

    Institute of Scientific and Technical Information of China (English)

    Hai-Long Yao; Yi-Ci Cai; Qiang Zhou; Xian-Long Hong

    2005-01-01

    Crosstalk noise is one of the emerging issues in deep sub-micrometer technology which causes many undesired effects on the circuit performance. In this paper, a Crosstalk-Aware Routing Resource Assignment (CARRA) algorithm is proposed, which integrates the routing layers and tracks to address the crosstalk noise issue during the track/layer assignment stage. The CARRA problem is formulated as a weighted bipartite matching problem and solved using the linear assignment algorithm. The crosstalk risks between nets are represented by an undirected graph and the maximum number of the concurrent crosstalk risking nets is computed as the max clique of the graph. Then the nets in each max clique are assigned to disadjacent tracks. Thus the crosstalk noise can be avoided based on the clique concept. The algorithm is tested on IBM benchmarks and the experimental results show that it can improve the final routing layout a lot with little loss of the completion rate.

  4. Prevention of Routing Attacks In Manet

    Directory of Open Access Journals (Sweden)

    N.Rajesh

    2013-01-01

    Full Text Available Mobile Ad hoc Networks (MANET are easily prone to attacks due to its network infrastructure. In previous routing attacks the malicious node is isolated using naive fuzzy response decisions. In this paper a new technology of broadcasting the awareness information about attacker node to all the existing nodes in the network is discussed. The awareness approach is based on an extended Dempster-Shafer mathematical theory(D-S Theory. Dempster-Shafer mathematical theory is used to collect the evidence notion of importance factors. The adaptiveness of the mechanism allows to systematically cope with the identified MANET routing attacks. The intrusion response action in MANET was addressed by isolating uncooperative nodes based on the node reputation derived from their behaviors. Here the effectiveness of the approach with the consideration of the packet delivery ratio and routing cost were demonstrated using java swing concepts

  5. Enabling Routes as Context in Mobile Services

    DEFF Research Database (Denmark)

    Brilingaite, Agne; Jensen, Christian Søndergaard; Zokaite, Nora

    by a small screen and no keyboard, and by the service being only a secondary focus of the user. Under such circumstances, it is particularly important to deliver the "right" information and service at the right time, with as little user interaction as possible. This may be achieved by making services context...... and accumulates the routes of a user along with their usage patterns and that makes the routes available to services. Experiences from using the component on logs of GPS positions acquired from vehicles traveling within a real road network are reported....

  6. Ambient noise near the sea-route

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Ambient noise data measured in an experiment conducted in shallow water near a sea-route were analyzed. It was observed that, at low frequency, the horizontal correlation has an obvious difference from that predicted by the classical ambient noise model. The theoretical analyses show that this phenomenon is caused by wind noise together with the discrete shipping noise nearby. An ambient noise model was proposed to include the effects caused by both the noise sources. Data measured at different times verify that the proposed model can be used to forecast the ambient noise field in shallow water near the sea-route.

  7. Ambient noise near the sea-route

    Institute of Scientific and Technical Information of China (English)

    HE Li; LI ZhengLin; PENG ZhaoHui

    2009-01-01

    Ambient noise data measured in an experiment conducted in shallow water near a sea-route were analyzed. It was observed that, at low frequency, the horizontal correlation has an obvious difference from that predicted by the classical ambient noise model. The theoretical analyses show that this phenomenon is caused by wind noise together with the discrete shipping noise nearby. An ambient noise model was proposed to include the effects caused by both the noise sources. Data measured at different times verify that the proposed model can be used to forecast the ambient noise field in shal-low water near the sea-route.

  8. Next Generation Network Routing and Control Plane

    DEFF Research Database (Denmark)

    Fu, Rong

    proved, the dominating Border Gateway Protocol (BGP) cannot address all the issues that in inter-domain QoS routing. Thus a new protocol or network architecture has to be developed to be able to carry the inter-domain traffic with the QoS and TE consideration. Moreover, the current network control also......-domain. It is a routing component that flexibly supports path computation with different requirements, constraints and areas. It is also can be seen as part of NGN transport control plane, which integrates with the other functions. In the aspect of resource control, an NGN release Resource and Admission Control Functions...

  9. The Team Orienteering Arc Routing Problem

    OpenAIRE

    Archetti, Claudia; Speranza, M. Grazia; Corberan, Angel; Sanchís Llopis, José María; Plana, Isaac

    2014-01-01

    The team orienteering arc routing problem (TOARP) is the extension to the arc routing setting of the team orienteering problem. In the TOARP, in addition to a possible set of regular customers that have to be serviced, another set of potential customers is available. Each customer is associated with an arc of a directed graph. Each potential customer has a profit that is collected when it is serviced, that is, when the associated arc is traversed. A fleet of vehicles with a given maximum trav...

  10. Reconfigurable Robust Routing for Mobile Outreach Network

    Science.gov (United States)

    Lin, Ching-Fang

    2010-01-01

    The Reconfigurable Robust Routing for Mobile Outreach Network (R3MOO N) provides advanced communications networking technologies suitable for the lunar surface environment and applications. The R3MOON techn ology is based on a detailed concept of operations tailored for luna r surface networks, and includes intelligent routing algorithms and wireless mesh network implementation on AGNC's Coremicro Robots. The product's features include an integrated communication solution inco rporating energy efficiency and disruption-tolerance in a mobile ad h oc network, and a real-time control module to provide researchers an d engineers a convenient tool for reconfiguration, investigation, an d management.

  11. An Improved Wireless Sensor Network Routing Algorithm

    Institute of Scientific and Technical Information of China (English)

    Shengmei Luo; Xue Li; Yiai Jin; Zhixin Sun

    2015-01-01

    High performance with low power consumption is an essential factor in wireless sensor networks (WSN). In order to address the issue on the lifetime and the consumption of nodes in WSNs, an improved ad hoc on⁃demand distance vector rout⁃ing (IAODV) algorithm is proposed based on AODV and LAR protocols. This algorithm is a modified on⁃demand routing al⁃gorithm that limits data forwarding in the searching domain, and then chooses the route on basis of hop count and power consumption. The simulation results show that the algorithm can effectively reduce power consumption as well as prolong the network lifetime.

  12. A Survey of Vehicle Routing Problem

    Directory of Open Access Journals (Sweden)

    Cao Wujun

    2017-01-01

    Full Text Available In recent years, vehicle routing problem (VRP has become an important content in logistics management research, and has been widely used in transportation system, logistics distribution system and express delivery system. In this paper, we discuss the classification of VRP, and summarize the common constraints of VRP, model algorithm and the main research results in recent years. Finally, we analyzes the future of VRP, and it is considered that the intelligent vehicle routing problem and intelligent heuristic algorithm will be an important field of future research.

  13. Mathematical Aspects of Network Routing Optimization

    CERN Document Server

    Oliveira, Carlos AS

    2011-01-01

    Before the appearance of broadband links and wireless systems, networks have been used to connect people in new ways. Now, the modern world is connected through large-scale, computational networked systems such as the Internet. Because of the ever-advancing technology of networking, efficient algorithms have become increasingly necessary to solve some of the problems developing in this area. "Mathematical Aspects of Network Routing Optimization" focuses on computational issues arising from the process of optimizing network routes, such as quality of the resulting links and their reli

  14. Optimized QoS Routing Algorithm

    Institute of Scientific and Technical Information of China (English)

    石明洪; 王思兵; 白英彩

    2004-01-01

    QoS routing is one of the key technologies for providing guaranteed service in IP networks. The paper focuses on the optimization problem for bandwidth constrained QoS routing, and proposes an optimal algorithm based on the global optimization of path bandwidth and hop counts. The main goal of the algorithm is to minimize the consumption of network resource, and at the same time to minimize the network congestion caused by irrational path selection. The simulation results show that our algorithm has lower call blocking rate and higher throughput than traditional algorithms.

  15. Network Congestion Control with Markovian Multipath Routing

    CERN Document Server

    Cominetti, Roberto

    2011-01-01

    In this paper we consider an integrated model for TCP/IP protocols with multipath routing. The model combines a Network Utility Maximization for rate control based on end-to-end queuing delays, with a Markovian Traffic Equilibrium for routing based on total expected delays. We prove the existence of a unique equilibrium state which is characterized as the solution of an unconstrained strictly convex program. A distributed algorithm for solving this optimization problem is proposed, with a brief discussion of how it can be implemented by adapting the current Internet protocols.

  16. BGP Route Analysis and Management Systems

    CERN Document Server

    Stewart, Alex A

    2009-01-01

    The Border Gateway Protocol (BGP) is an important component in today's IP network infrastructure. As the main routing protocol of the Internet, clear understanding of its dynamics is crucial for configuring, diagnosing and debugging Internet routing problems. Despite the increase in the services that BGP provide such as MPLS VPNs, there is no much progress achieved in automating the BGP management tasks. In this paper we discuss some of the problems encountered by network engineers when managing BGP networks. We also describe some of the open source tools and methods that attempt to resolve these issues. Then we present some of the features that, if implemented, will ease BGP management related tasks.

  17. Air Pollution

    Science.gov (United States)

    ... to view this content or go to source URL . What NIEHS is Doing on Air Pollution Who ... Junction Last Reviewed: February 06, 2017 This page URL: NIEHS website: https://www.niehs.nih.gov/ Email ...

  18. Real Time Route for Dynamic Road Congestions

    Directory of Open Access Journals (Sweden)

    A. M. Riad

    2012-05-01

    Full Text Available Minimizing service delivery and travel time during rush hours downtown is strategic target for several organizations, especially the emergency organizations. This paper presents an On-line and Real-time Dynamic Route System (ORDRS which benefits from the advantages and integration between information system and communications technology. It utilizes Global Positioning System (GPS, Geographical Information Systems (GIS, and Global System for Mobile communications (GSM; for producing the real time routes for vehicles. GPS-Tracker is the main input device for ORDRS. It is fixated in a vehicle, sends vehicle's movement data (Geo-info to the control center wirelessly through either Short Message Service (SMS or General Packet Radio Service (GPRS. Geo-info includes time, date, longitude, latitude, speed, and etc., these data is classified over time during weekdays into interval time slices, each slice is 30 minutes. Speeds are treated by GIS tools to determine historical and real time speeds for each street segment in the road network which is being used for calculating time impedance (cost matrix for each street segment dynamically. ORDRS uses a cost matrix of the current time slice for determining the best route to each vehicle in duty attached. Several algorithms was used to calculate the shortest route, a comparison between Dijekstra and Yen algorithms was studied.

  19. Obsidian trade routes in the mayan area.

    Science.gov (United States)

    Hammond, N

    1972-12-08

    Obsidian from two sources in highland Guatemala has been found at 23 sites of the Classic Mayan civilization, mainly in the nonvolcanic lowlands to the north. The distribution, together with trade routes suggested by topography and documentary sources, suggests efficient waterborne transport and competition between sources for the lowland market.

  20. Traffic disruption route Einstein near building 170

    CERN Multimedia

    A Lopez - TS/CE

    2005-01-01

    The TS/CE Group informs you that, for the duration of the work at Building 170, there may be some disruption to traffic on route Einstein in the vicinity of Building 170. The work is due to take place from the 14th to 18th February. For more information, please contact 165029. A. Lopez TS/CE

  1. MULTINOMINAL LOGIT MODEL OF BICYCLIST ROUTE CHOICE

    Directory of Open Access Journals (Sweden)

    O. Chernyshova

    2016-06-01

    Full Text Available The paper presents the multinominal logit discrete choice model that allows determining parameters coefficients of the cyclists’ route. The basic model includes six parameters, however, only a number of signalized intersections, speed of motorized traffic and total physical work required from cyclist prove to be significant factors. The model provides a better understanding about cyclist traffic assignment.

  2. Graphical route information on variable message signs

    NARCIS (Netherlands)

    Alkim, T.P.; Mede, P.H.J. van der; Janssen, W.H.

    2002-01-01

    Reports on experiments in the Netherlands on the use of graphical route information panels (GRIP) as part of variable message systems (VMS) providing information to drivers. GRIP appear to be as safe as regular VMS. Digestion of the information presented is initially quicker for regular VMS, but mot

  3. Partially dynamic vehicle routing - models and algorithms

    DEFF Research Database (Denmark)

    Larsen, Allan; Madsen, Oli B.G.; Solomon, M.

    2002-01-01

    In this paper we propose a framework for dynamic routing systems based on their degree of dynamism. Next, we consider its impact on solution methodology and quality. Specifically, we introduce the Partially Dynamic Travelling Repairman Problem and describe several dynamic policies to minimize rou...

  4. Locating Depots for Capacitated Vehicle Routing

    CERN Document Server

    Goertz, Inge Li

    2011-01-01

    We study a location-routing problem in the context of capacitated vehicle routing. The input is a set of demand locations in a metric space and a fleet of k vehicles each of capacity Q. The objective is to locate k depots, one for each vehicle, and compute routes for the vehicles so that all demands are satisfied and the total cost is minimized. Our main result is a constant-factor approximation algorithm for this problem. To achieve this result, we reduce to the k-median-forest problem, which generalizes both k-median and minimum spanning tree, and which might be of independent interest. We give a (3+c)-approximation algorithm for k-median-forest, which leads to a (12+c)-approximation algorithm for the above location-routing problem, for any constant c>0. The algorithm for k-median-forest is just t-swap local search, and we prove that it has locality gap 3+2/t; this generalizes the corresponding result known for k-median. Finally we consider the "non-uniform" k-median-forest problem which has different cost ...

  5. ROUTE PLAN DESIGNER FOR TRACTOR GUIDANCE SYSTEMS

    DEFF Research Database (Denmark)

    Sveistrup, Daniel; Jørgensen, Rasmus Nyholm; Green, Ole

    2010-01-01

    Earlier works have shown field trial designs to be very labor extensive, even when combining autoguidancesystems with conventional machinery.Designing routes for semi-automated systems in a controlled manner is both resource demandingand complicated. Different types of auto-guidance systems vary ...

  6. The route to protein aggregate superstructures

    DEFF Research Database (Denmark)

    Vetri, Valeria; Foderà, Vito

    2015-01-01

    Depending on external conditions, native proteins may change their structure and undergo different association routes leading to a large scale polymorphism of the aggregates. This feature has been widely observed but is not fully understood yet. This review focuses on morphologies, physico-chemical...

  7. A Geographical Heuristic Routing Protocol for VANETs

    Directory of Open Access Journals (Sweden)

    Luis Urquiza-Aguiar

    2016-09-01

    Full Text Available Vehicular ad hoc networks (VANETs leverage the communication system of Intelligent Transportation Systems (ITS. Recently, Delay-Tolerant Network (DTN routing protocols have increased their popularity among the research community for being used in non-safety VANET applications and services like traffic reporting. Vehicular DTN protocols use geographical and local information to make forwarding decisions. However, current proposals only consider the selection of the best candidate based on a local-search. In this paper, we propose a generic Geographical Heuristic Routing (GHR protocol that can be applied to any DTN geographical routing protocol that makes forwarding decisions hop by hop. GHR includes in its operation adaptations simulated annealing and Tabu-search meta-heuristics, which have largely been used to improve local-search results in discrete optimization. We include a complete performance evaluation of GHR in a multi-hop VANET simulation scenario for a reporting service. Our study analyzes all of the meaningful configurations of GHR and offers a statistical analysis of our findings by means of MANOVA tests. Our results indicate that the use of a Tabu list contributes to improving the packet delivery ratio by around 5% to 10%. Moreover, if Tabu is used, then the simulated annealing routing strategy gets a better performance than the selection of the best node used with carry and forwarding (default operation.

  8. Issues of Simulation-Based Route Assignment

    Energy Technology Data Exchange (ETDEWEB)

    Nagel, K.; Rickert, M.

    1999-07-20

    The authors use an iterative re-planning scheme with simulation feedback to generate a self-consistent route-set for a given street network and origin-destination matrix. The iteration process is defined by three parameters. They found that they have influence on the speed of the relaxation, but not necessarily on its final state.

  9. Phone Routing using the Dynamic Memory Model

    DEFF Research Database (Denmark)

    Bendtsen, Claus Nicolaj; Krink, Thiemo

    2002-01-01

    In earlier studies a genetic algorithm (GA) extended with the dynamic memory model has shown remarkable performance on real-world-like problems. In this paper we experiment with routing in communication networks and show that the dynamic memory GA performs remarkable well compared to ant colony o...

  10. Energy-Efficient Routing in GMPLS Network

    DEFF Research Database (Denmark)

    Wang, Jiayuan; Fagertun, Anna Manolova; Ruepp, Sarah Renée;

    2011-01-01

    In this paper, a GMPLS controlled core network model that takes energy efficiency into account is built using OPNET MODELER. By extending the standard GMPLS routing protocol -- OSPF-TE, we are able to spread desired energy related information over the local area, and subsequently use RSVP...

  11. Overview of Stochastic Vehicle Routing Problems

    Institute of Scientific and Technical Information of China (English)

    郭耀煌; 谢秉磊; 郭强

    2002-01-01

    Stochastic vehicle routing problems (VRPs) play important roles in logistics, though they have not been studied systematically yet. The paper summaries the definition, properties and classification of stochastic VRPs, makes further discussion about two strategies in stochastic VRPs, and at last overviews dynamic and stochastic VRPs.

  12. Norton's theorem for batch routing queueing networks

    NARCIS (Netherlands)

    Bause, Falko; Boucherie, Richard J.; Buchholz, Peter

    2001-01-01

    This paper shows that the aggregation and decomposition result known as Norton’s theorem for queueing networks can be extended to a general class of batch routing queueing networks with product-form solution that allows for multiple components to simultaneously release and receive (batches of) custo

  13. An Efficient Routing Algorithm in Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    WANGShuqiao; LIHongyan; LIJiandong

    2005-01-01

    The Dynamic source routing protocol(DSR) is an on-demand routing protocol, designed specifically for use in multi-hop wireless ad hoc networks of mobile nodes. In this paper, some mechanisms such as the route's lifetime prediction, route’s creation time and an adaptive gratuitous route reply mode are introduced into DSR to get an efficient routing algorithm which is refered to E-DSR. The simulation results show that E-DSR can improve the packet delivery rate and reduce the routing overhead compared with hop-based DSR.

  14. Escape probability based routing for ad hoc networks

    Institute of Scientific and Technical Information of China (English)

    Zhang Xuanping; Qin Zheng; Li Xin

    2006-01-01

    Routes in an ad hoc network may fail frequently because of node mobility. Stability therefore can be an important element in the design of routing protocols. The node escape probability is introduced to estimate the lifetime and stability of link between neighboring nodes and the escape probability based routing (EPBR) scheme to discover stable routes is proposed. Simulation results show that the EPBR can discover stable routes to reduce the number of route rediscovery, and is applicable for the situation that has highly dynamic network topology with broad area of communication.

  15. Research on network failure handling technology based on deflection routing

    Institute of Scientific and Technical Information of China (English)

    Tao YU; Shanzhi CHEN; Xin LI; Zhen QIN

    2008-01-01

    A new deflection routing scheme is proposed to overcome the drawback of existing deflection routing scheme that cannot handle node failure and suffer from routing loops.A new algorithm for computing the backup shortest path tree(SPT)is proposed and a set of procedures are defined for utilizing the backup SPT in case of node or link failure.The failure can be handled swiftly and the backup routes are guaranteed to be loop-free.Experimental results show that the backup routes calculated by proposed scheme are close to the optimal routes by totally re-computing.

  16. Optimal Route Selection Method Based on Vague Sets

    Institute of Scientific and Technical Information of China (English)

    GUO Rui; DU Li min; WANG Chun

    2015-01-01

    Optimal route selection is an important function of vehicle trac flow guidance system. Its core is to determine the index weight for measuring the route merits and to determine the evaluation method for selecting route. In this paper, subjective weighting method which relies on driver preference is used to determine the weight and the paper proposes the multi-criteria weighted decision method based on vague sets for selecting the optimal route. Examples show that, the usage of vague sets to describe route index value can provide more decision-making information for route selection.

  17. Route guidance strategies revisited: Comparison and evaluation in an asymmetric two-route traffic system

    CERN Document Server

    He, Zhengbing; Guan, Wei

    2013-01-01

    To alleviate traffic congestion, a variety of route guidance strategies has been proposed for intelligent transportation systems. A number of the strategies are proposed and investigated on a symmetric two-route traffic system over the past decade. To evaluate the strategies in a more general scenario, this paper conducts eight prevalent strategies on a asymmetric two-route traffic network with different slowdown behaviors on alternative routes. The results show that only mean velocity feedback strategy is able to equalize travel time, i.e., approximate user optimality; while the others fail due to incapability of establishing relations between the feedback parameters and travel time. The paper helps better understand these strategies, and suggests mean velocity feedback strategy if the authority intends to achieve user optimality.

  18. PNW River Reach Files -- 1:100k LLID Routed Streams (routes)

    Data.gov (United States)

    Pacific States Marine Fisheries Commission — This feature class includes the ROUTE features from the 2001 version of the PNW River Reach files Arc/INFO coverage. Separate, companion feature classes are also...

  19. A Maximum Entropy Fixed-Point Route Choice Model for Route Correlation

    Directory of Open Access Journals (Sweden)

    Louis de Grange

    2014-06-01

    Full Text Available In this paper we present a stochastic route choice model for transit networks that explicitly addresses route correlation due to overlapping alternatives. The model is based on a multi-objective mathematical programming problem, the optimality conditions of which generate an extension to the Multinomial Logit models. The proposed model considers a fixed point problem for treating correlations between routes, which can be solved iteratively. We estimated the new model on the Santiago (Chile Metro network and compared the results with other route choice models that can be found in the literature. The new model has better explanatory and predictive power that many other alternative models, correctly capturing the correlation factor. Our methodology can be extended to private transport networks.

  20. Aerosol immunisation for TB: matching route of vaccination to route of infection.

    Science.gov (United States)

    Manjaly Thomas, Zita-Rose; McShane, Helen

    2015-03-01

    TB remains a very significant global health burden. There is an urgent need for better tools for TB control, which include an effective vaccine. Bacillus Calmette-Guérin (BCG), the currently licensed vaccine, confers highly variable protection against pulmonary TB, the main source of TB transmission. Replacing BCG completely or boosting BCG with another vaccine are the two current strategies for TB vaccine development. Delivering a vaccine by aerosol represents a way to match the route of vaccination to the route of infection. This route of immunisation offers not only the scientific advantage of delivering the vaccine directly to the respiratory mucosa, but also practical and logistical advantages. This review summarises the state of current TB vaccine candidates in the pipeline, reviews current progress in aerosol administration of vaccines in general and evaluates the potential for TB vaccine candidates to be administered by the aerosol route.

  1. Vehicle routing problem and capacitated vehicle routing problem frameworks in fund allocation problem

    Science.gov (United States)

    Mamat, Nur Jumaadzan Zaleha; Jaaman, Saiful Hafizah; Ahmad, Rokiah@Rozita

    2016-11-01

    Two new methods adopted from methods commonly used in the field of transportation and logistics are proposed to solve a specific issue of investment allocation problem. Vehicle routing problem and capacitated vehicle routing methods are applied to optimize the fund allocation of a portfolio of investment assets. This is done by determining the sequence of the assets. As a result, total investment risk is minimized by this sequence.

  2. Inhalation a significant exposure route for chlorinated organophosphate flame retardants.

    Science.gov (United States)

    Schreder, Erika D; Uding, Nancy; La Guardia, Mark J

    2016-05-01

    Chlorinated organophosphate flame retardants (ClOPFRs) are widely used as additive flame retardants in consumer products including furniture, children's products, building materials, and textiles. Tests of indoor media in homes, offices, and other environments have shown these compounds are released from products and have become ubiquitous indoor pollutants. In house dust samples from Washington State, U.S.A., ClOPFRs were the flame retardants detected in the highest concentrations. Two ClOPFRs, tris(1,3-dichloro-2-propyl)phosphate (TDCPP or TDCIPP) and tris(2-chloroethyl)phosphate (TCEP), have been designated as carcinogens, and there is growing concern about the toxicity of the homologue tris(1-chloro-2-propyl)phosphate (TCPP or TCIPP). In response to concerns about exposure to these compounds, the European Union and a number of U.S. states have taken regulatory action to restrict their use in certain product categories. To better characterize exposure to ClOPFRs, inhalation exposure was assessed using active personal air samplers in Washington State with both respirable and inhalable particulate fractions collected to assess the likelihood particles penetrate deep into the lungs. Concentrations of ∑ClOPFRs (respirable and inhalable) ranged from 97.1 to 1190 ng m(-3) (mean 426 ng m(-3)), with TCPP detected at the highest concentrations. In general, higher levels were detected in the inhalable particulate fraction. Total intake of ClOPFRs via the inhalation exposure route was estimated to exceed intake via dust ingestion, indicating that inhalation is an important route that should be taken into consideration in assessments of these compounds.

  3. Route Recapitulation and Route Loyalty in Homing Pigeons: Pilotage From 25 km?

    Science.gov (United States)

    Biro, Dora; Meade, Jessica; Guilford, Tim

    2006-01-01

    We utilised precision Global Positioning System (GPS) tracking to examine the homing paths of pigeons (Columba livia) released 20 times consecutively 25 km from the loft. By the end of the training phase, birds had developed highly stereotyped yet individually distinct routes home, with detailed recapitulation evident at each stage of the journey. Following training, birds also participated in a series of releases from novel sites at perpendicular distances of up to 3 km from their established routes. Results showed that subjects were attracted back to their established routes and recapitulated them from the point of contact. Naïve conspecifics (yoked controls) released from the same off-route sites confirmed that the experienced birds' route choices were not influenced by constraints exerted by terrain features, but that increased experience with the general area conferred a homing advantage in the form of more efficient flight tracks, even from these novel sites. Patterns in the paths taken by experienced birds to rejoin their established routes are discussed with reference to navigational mechanisms employed by homing pigeons in their familiar area.

  4. Optimal Route Based Advanced Algorithm using Hot Link Split Multi-Path Routing Algorithm

    Directory of Open Access Journals (Sweden)

    Akhilesh A. Waoo

    2014-07-01

    Full Text Available Present research work describes advancement in standard routing protocol AODV for mobile ad-hoc networks. Our mechanism sets up multiple optimal paths with the criteria of bandwidth and delay to store multiple optimal paths in the network. At time of link failure, it will switch to next available path. We have used the information that we get in the RREQ packet and also send RREP packet to more than one path, to set up multiple paths, It reduces overhead of local route discovery at the time of link failure and because of this End to End Delay and Drop Ratio decreases. The main feature of our mechanism is its simplicity and improved efficiency. This evaluates through simulations the performance of the AODV routing protocol including our scheme and we compare it with HLSMPRA (Hot Link Split Multi-Path Routing Algorithm Algorithm. Indeed, our scheme reduces routing load of network, end to end delay, packet drop ratio, and route error sent. The simulations have been performed using network simulator OPNET. The network simulator OPNET is discrete event simulation software for network simulations which means it simulates events not only sending and receiving packets but also forwarding and dropping packets. This modified algorithm has improved efficiency, with more reliability than Previous Algorithm.

  5. Congestion control and routing over satellite networks

    Science.gov (United States)

    Cao, Jinhua

    Satellite networks and transmissions find their application in fields of computer communications, telephone communications, television broadcasting, transportation, space situational awareness systems and so on. This thesis mainly focuses on two networking issues affecting satellite networking: network congestion control and network routing optimization. Congestion, which leads to long queueing delays, packet losses or both, is a networking problem that has drawn the attention of many researchers. The goal of congestion control mechanisms is to ensure high bandwidth utilization while avoiding network congestion by regulating the rate at which traffic sources inject packets into a network. In this thesis, we propose a stable congestion controller using data-driven, safe switching control theory to improve the dynamic performance of satellite Transmission Control Protocol/Active Queue Management (TCP/AQM) networks. First, the stable region of the Proportional-Integral (PI) parameters for a nominal model is explored. Then, a PI controller, whose parameters are adaptively tuned by switching among members of a given candidate set, using observed plant data, is presented and compared with some classical AQM policy examples, such as Random Early Detection (RED) and fixed PI control. A new cost detectable switching law with an interval cost function switching algorithm, which improves the performance and also saves the computational cost, is developed and compared with a law commonly used in the switching control literature. Finite-gain stability of the system is proved. A fuzzy logic PI controller is incorporated as a special candidate to achieve good performance at all nominal points with the available set of candidate controllers. Simulations are presented to validate the theory. An effocient routing algorithm plays a key role in optimizing network resources. In this thesis, we briefly analyze Low Earth Orbit (LEO) satellite networks, review the Cross Entropy (CE

  6. Nanostructured aluminium oxide powders obtained by aspartic acid-nitrate gel-combustion routes

    Energy Technology Data Exchange (ETDEWEB)

    Gardey Merino, Maria Celeste, E-mail: mcgardey@frm.utn.edu.a [Laboratorio de Investigaciones y Servicios Ambientales Mendoza (LISAMEN) - CCT - CONICET, Avda. Ruiz Leal s/n, Parque Gral. San Martin, (M5502IRA) Ciudad de Mendoza, Prov. de Mendoza (Argentina); Grupo CLIOPE, Universidad Tecnologica Nacional - Facultad Regional Mendoza, Rodriguez 273, (M5502AJE) Ciudad de Mendoza, Prov. de Mendoza (Argentina); Lascalea, Gustavo E. [Laboratorio de Investigaciones y Servicios Ambientales Mendoza (LISAMEN) - CCT - CONICET, Avda. Ruiz Leal s/n, Parque Gral. San Martin, (M5502IRA) Ciudad de Mendoza, Prov. de Mendoza (Argentina); Sanchez, Laura M. [CINSO (Centro de Investigaciones en Solidos), CITEFA - CONICET, J.B. de La Salle 4397, (B1603ALO) Villa Martelli, Prov. de Buenos Aires (Argentina); Vazquez, Patricia G. [Centro de Investigacion y Desarrollo en Ciencias Aplicadas ' Dr. Jorge J. Ronco' (CINDECA), CONICET, Universidad Nacional de La Plata, Calle 47 nro. 257, (B1900AJK) La Plata, Prov. de Buenos Aires (Argentina); Cabanillas, Edgardo D. [CONICET and Centro Atomico Constituyentes, Comision Nacional de Energia Atomica, Gral. Paz 1499, (1650) San Martin, Prov. de Buenos Aires (Argentina); Lamas, Diego G. [CINSO (Centro de Investigaciones en Solidos), CITEFA - CONICET, J.B. de La Salle 4397, (B1603ALO) Villa Martelli, Prov. de Buenos Aires (Argentina)

    2010-04-16

    In this work, two new gel-combustion routes for the synthesis of Al{sub 2}O{sub 3} nanopowders with aspartic acid as fuel are presented. The first route is a conventional stoichiometric process, while the second one is a non-stoichiometric, pH-controlled process. These routes were compared with similar synthesis procedures using glycine as fuel, which are well-known in the literature. The samples were calcined in air at different temperatures, in a range of 600-1200 {sup o}C. They were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and BET specific surface area. Different phases were obtained depending on the calcination temperature: amorphous, {gamma} (metastable) or {alpha} (stable). The amorphous-to-{gamma} transition was found for calcination temperatures in the range of 700-900 {sup o}C, while the {gamma}-to-{alpha} one was observed for calcination temperatures of 1100-1200 {sup o}C. The retention of the metastable {gamma} phase is probably due to a crystallite size effect. It transforms to the {alpha} phase after the crystallite size increases over a critical size during the calcination process at 1200 {sup o}C. The highest BET specific surface areas were obtained for both nitrate-aspartic acid routes proposed in this work, reaching values of about 50 m{sup 2}/g.

  7. Manufacturing of self-passivating tungsten based alloys by different powder metallurgical routes

    Science.gov (United States)

    Calvo, A.; Ordás, N.; Iturriza, I.; Pastor, J. Y.; Tejado, E.; Palacios, T.; García-Rosales, C.

    2016-02-01

    Self-passivating tungsten based alloys will provide a major safety advantage compared to pure tungsten when used as first wall armor of future fusion reactors, due to the formation of a protective oxide layer which prevents the formation of volatile and radioactive WO3 in case of a loss of coolant accident with simultaneous air ingress. Bulk WCr10Ti2 alloys were manufactured by two different powder metallurgical routes: (1) mechanical alloying (MA) followed by hot isostatic pressing (HIP) of metallic capsules, and (2) MA, compaction, pressureless sintering in H2 and subsequent HIPing without encapsulation. Both routes resulted in fully dense materials with homogeneous microstructure and grain sizes of 300 nm and 1 μm, respectively. The content of impurities remained unchanged after HIP, but it increased after sintering due to binder residue. It was not possible to produce large samples by route (2) due to difficulties in the uniaxial compaction stage. Flexural strength and fracture toughness measured on samples produced by route (1) revealed a ductile-to-brittle-transition temperature (DBTT) of about 950 °C. The strength increased from room temperature to 800 °C, decreasing significantly in the plastic region. An increase of fracture toughness is observed around the DBTT.

  8. Stateless and Delivery Guaranteed Geometric Routing on Virtual Coordinate System

    CERN Document Server

    Liu, Ke

    2008-01-01

    Stateless geographic routing provides relatively good performance at a fixed overhead, which is typically much lower than conventional routing protocols such as AODV. However, the performance of geographic routing is impacted by physical voids, and localization errors. Accordingly, virtual coordinate systems (VCS) were proposed as an alternative approach that is resilient to localization errors and that naturally routes around physical voids. However, VCS also faces virtual anomalies, causing their performance to trail geographic routing. In existing VCS routing protocols, there is a lack of an effective stateless and delivery guaranteed complementary routing algorithm that can be used to traverse voids. Most proposed solutions use variants of flooding or blind searching when a void is encountered. In this paper, we propose a spanning-path virtual coordinate system which can be used as a complete routing algorithm or as the complementary algorithm to greedy forwarding that is invoked when voids are encountere...

  9. Use of Interactive Computer Graphics to Solve Routing Problems.

    Science.gov (United States)

    Gillett, B. E.; Lawrence, J. L.

    1981-01-01

    Discusses vehicle routing problems and solutions. Describes testing of an interactive computer graphics package combining several types of solutions that allows users with little or no experience to work out routing problems. (Author/RW)

  10. Air surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Patton, G.W.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the air surveillance and monitoring programs currently in operation at that Hanford Site. Atmospheric releases of pollutants from Hanford to the surrounding region are a potential source of human exposure. For that reason, both radioactive and nonradioactive materials in air are monitored at a number of locations. The influence of Hanford emissions on local radionuclide concentrations was evaluated by comparing concentrations measured at distant locations within the region to concentrations measured at the Site perimeter. This section discusses sample collection, analytical methods, and the results of the Hanford air surveillance program. A complete listing of all analytical results summarized in this section is reported separately by Bisping (1995).

  11. A Study on Competitiveness of Sea Transport by Comparing International Transport Routes between Korea and EU

    Directory of Open Access Journals (Sweden)

    Dae-seop Moon

    2015-03-01

    Route 1 was found the most competitive, and Route 5, the most widely used sea way was ranked the lowest. In addition, the new transport routes, Route 1 and 6 are shown to be more competitive than the currently available routes, Route 2, 3 and 4. However, these routes need national level supports (rail construction for Route 1 and subsidy plan for Route 6 for the commercial use in the future.

  12. Vehicle Routing Algorithms for Local Delivery at Naval Supply Centers.

    Science.gov (United States)

    1981-03-01

    the purpose of selecting a vehicle routing algorithm that can be automated. This investigation led the author to a survey of " vehicle routing problem " (also...the vehicle routing problem model is described and solution techniques are sur- veyed. Additionally, computational experience that operations...researchers have had with these solution techniques is pre- sented. There are several classical and theoretical problems related to the vehicle routing problem . These

  13. An Approach In Optimization Of Ad-Hoc Routing Algorithms

    Directory of Open Access Journals (Sweden)

    Sarvesh Kumar Sharma

    2012-06-01

    Full Text Available In this paper different optimization of Ad-hoc routing algorithm is surveyed and a new method using training based optimization algorithm for reducing the complexity of routing algorithms is suggested. A binary matrix is assigned to each node in the network and gets updated after each data transfer using the protocols. The use of optimization algorithm in routing algorithm can reduce the complexity of routing to the least amount possible.

  14. An Application of Intuitionistic Fuzzy in Routing Networks

    Directory of Open Access Journals (Sweden)

    Ashit Kumar Dutta

    2012-06-01

    Full Text Available Routing is an important functional aspect of networks to transport packets from source to destination. A router sets up optimized paths among the different nodes in the network. In this paper the authors proposed a new type of routing algorithm which includes exchange of routing information for small amount of time and then halts for few hours but this information is used by each router to make its own routing decisions based on intuitionistic fuzzy logic during these hours.

  15. Solving Segment Routing Problems with Hybrid Constraint Programming Techniques

    OpenAIRE

    Hartert, Renaud; Schaus, Pierre; Vissicchio, Stefano; Bonaventure, Olivier; International Conference on Principles and Practice of Constraint Programming (CP2014)

    2015-01-01

    Segment routing is an emerging network technology that exploits the existence of several paths between a source and a destination to spread the traffic in a simple and elegant way. The major commercial network vendors already support segment routing, and several Internet actors are ready to use segment routing in their network. Unfortunately, by changing the way paths are computed, segment routing poses new op- timization problems which cannot be addressed with previous research contributions...

  16. Link Perdurability Based Routing for Mobile Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    Sun Xuebin; Zhou Zheng

    2003-01-01

    Ad Hoc networks are prone to link failures due to mobility. In this letter, a link perdurability based routing scheme is proposed to try dealing with this problem. This scheme uses signal strength measurements to estimate the route life time and hence chooses a stable route, and is implemented in two typical ad hoc routing protocols to evaluate its performance. The simulation results have shown that this scheme can improve these protocols' packet delivery ratio in cases where there are frequent link failures.

  17. A Tabu Search Heuristic for the Vehicle Routing Problem

    OpenAIRE

    1994-01-01

    The purpose of this paper is to describe TABUROUTE, a new tabu search heuristic for the vehicle routing problem with capacity and route length restrictions. The algorithm considers a sequence of adjacent solutions obtained by repeatedly removing a vertex from its current route and reinserting it into another route. This is done by means of a generalized insertion procedure previously developed by the authors. During the course of the algorithm, infeasible solutions are allowed. Numerical test...

  18. SPEED: A Real-Time Routing Protocol for Sensor Networks

    Science.gov (United States)

    2007-11-02

    guarantees, which were not the main goals of previous location-based routing protocols . Reactive routing algorithms such as AODV [11], DSR[5] and TORA [10...1 SPEED: A Real-Time Routing Protocol for Sensor Networks1 Tian He John A Stankovic Chenyang Lu Tarek Abdelzaher Department of...control packet overhead. 2. State of thea Art A number of routing protocols (e.g., [2] [5] [8] [11] [12]) have been developed for ad hoc wireless

  19. Optimal Differential Routing based on Finite State Machine Theory

    OpenAIRE

    M. S. Krishnamoorthy; Loy, James R.; McDonald, John F.

    1999-01-01

    Noise margins in high speed digital systems continue to erode. Full differential signal routing provides a mechanism for deferring these effects. This paper proposes a three stage routing process for solving the adjacent placement routing problem of differential signal pairs, and proves that it is optimal. The process views differential pairs as logical nets; routes the logical nets; then bifurcates the result to achieve a physical realization. Finite state machine theory provides the critica...

  20. Traffic modifications on Routes Rutherford, Democrite and Fermi

    CERN Multimedia

    2015-01-01

    The GS Department would like to inform you that until the end of December, the construction of Building 245 will result in the following traffic modifications: Traffic on Route Rutherford will be partially restricted in front of the construction site, Traffic on Route Democrite will be one-way towards Route Rutherford. Also, please note that due to construction work in front of Building 377, Route Fermi will be closed from Wednesday, 10 June until Friday, 7 August. Thank you for your understanding.

  1. Eco-sustainable routing in optical networks

    DEFF Research Database (Denmark)

    Ricciardi, Sergio; Wang, Jiayuan; Palmieri, Francesco;

    2013-01-01

    infrastructures are now widely recognized to play a fundamental role in the emission of green-house gases (GHG) in the at- mosphere, signicantly aecting the environmental sustainability of new evolutions in network architectures as well as technological developments in communication devices. In this paper......It is quite easy to foresee that in the next years, the future generation ultra-high speed network infrastructures and equipments will be no longer constrained only by their pure transport capacity, but also by their energy consumption costs and environmental eects. In particular, large network......, a novel eco-sustainable Routing and Wavelength Assignment (RWA) algorithm, based on shortest-path routing with an adaptive link weighting function relying on an extension of the OSPF-TE protocol to convey carbon footprint information, has been proposed to decrease the network ecological impact while...

  2. On the Lorentzian route to Relativity

    CERN Document Server

    Gürel, Atilla

    2011-01-01

    We discuss pedagogical problems associated with the conventional approach in teaching relativity and the potential value of "Lorentzian route to relativity" for addressing these pedagogical problems. We think that Lorentzian approach may be valuable part of an introduction to relativity but the historical route should be followed up to its end. It must namely include Einstein's application of Occam's razor in reinterpreting Lorentz transformations kinematically and the discussion of the central role of the evolution from Lorentz's "local time" to relativity of simultaneity. We discuss also what Occam's razor is not and why it should not cut "too deeply or too permanently". Some misleading remarks in relativity text books concerning for example Kennedy Thorndike experiment and Trouton-Noble experiment indicate the not uncommon lack of awareness about the degree observational equivalence between prerelativistic (Lorentzian) and relativistic viewpoints as far as special relativistic experiments are considered. K...

  3. Enhanced PMIPv6 Route Optimization Handover

    Science.gov (United States)

    Jeon, Seil; Kang, Namhi; Kim, Younghan; Yoon, Wonsik

    Packet delivery in Proxy Mobile IPv6 (PMIPv6) relies on an anchor node called LMA. All packets sent by a source node reach a receiver node via LMA, even though the two nodes attach to the same MAG. In some scenarios, PMIPv6 results in high delivery latency and processing costs due to this unnecessary detour. To address this issue, several PMIPv6 route optimization schemes have been proposed. However, high signaling costs and excessive delays remain when handover is performed. For this reason, we propose an enhanced PMIPv6 route optimization (EPRO) scheme. In addition, we analyze the performance of the EPRO. Analytical results indicate that the EPRO outperforms previous schemes in terms of signaling overhead and handover latency.

  4. Multicast Routing Based on Hybrid Genetic Algorithm

    Institute of Scientific and Technical Information of China (English)

    CAO Yuan-da; CAI Gui

    2005-01-01

    A new multicast routing algorithm based on the hybrid genetic algorithm (HGA) is proposed. The coding pattern based on the number of routing paths is used. A fitness function that is computed easily and makes algorithm quickly convergent is proposed. A new approach that defines the HGA's parameters is provided. The simulation shows that the approach can increase largely the convergent ratio, and the fitting values of the parameters of this algorithm are different from that of the original algorithms. The optimal mutation probability of HGA equals 0.50 in HGA in the experiment, but that equals 0.07 in SGA. It has been concluded that the population size has a significant influence on the HGA's convergent ratio when it's mutation probability is bigger. The algorithm with a small population size has a high average convergent rate. The population size has little influence on HGA with the lower mutation probability.

  5. Effective Privacy-Preserving Online Route Planning

    DEFF Research Database (Denmark)

    Vicente, Carmen Ruiz; Assent, Ira; Jensen, Christian S.

    2011-01-01

    An online Route Planning Service (RPS) computes a route from one location to another. Current RPSs such as Google Maps require the use of precise locations. However, some users may not want to disclose their source and destination locations due to privacy concerns. An approach that supplies fake...... privacy. The solution re-uses a standard online RPS rather than replicate this functionality, and it needs no trusted third party. The solution is able to compute the exact results without leaking of the exact locations to the RPS or un-trusted parties. In addition, we provide heuristics that reduce...... the number of times that the RPS needs to be queried, and we also describe how the accuracy and privacy requirements can be relaxed to achieve better performance. An empirical study offers insight into key properties of the approach....

  6. Multicast Routing Protocols in Adhoc Mobile networks

    Directory of Open Access Journals (Sweden)

    S.Nagaprasad,

    2010-11-01

    Full Text Available The majority of applications are in areas where rapid deployment and dynamic reconfiguration are necessary and a wire line network is not available. These include military battlefields, emergency search and rescue sites, classrooms, and conventions where participants share information dynamically using their mobile devices. Well established routing protocols do exist to offer efficient multicasting service in conventional wired networks. These protocols, having been designed for fixed networks, may fails to keep up with node movements and frequent topology changes in a MANET. Therefore, adapting existing wired multicast protocols as such to a MANET, which completely lacks infrastructure, appear less promising. Providing efficient multicasting over MANET faces many challenges, includes scalability,quality of service, reliable service, security, Address configuration, Applications for multicast over MANET. The existing multicast routing protocol do not addresses these issues effectively over Mobile Adhoc Networks (MANET.

  7. Secure Routing in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Soumyashree Sahoo

    2012-01-01

    Full Text Available Wireless sensor networks is the new concept in the field of networks consists of small, large number of sensing nodes which is having the sensing, computational and transmission power. Due to lack of tamper-resistant infrastructure and the insecure nature of wireless communication channels, these networks are vulnerable to internal and external attacks. Key Management is a major challenge to achieve security in wireless sensor networks. Key management includes the process of key setup, the initial distribution of keys and keys revocation. To provide security and proper routing or communication should be encrypted and authenticated. It is not easy to achieve secure key establishment without public key cryptography. In this thesis, some key management schemes have been purposed which will be valuable for secure routing between different sensor nodes.

  8. Adaptive Routing Algorithm for MANET:TERMITE

    Directory of Open Access Journals (Sweden)

    Sharvani G S

    2009-12-01

    Full Text Available Mobile Ad hoc network consists of a set of mobile nodes. This network does not have anyinfrastructure or central administration, hence it is called infrastructure less network. As the nodes aremobile, it is very difficult to find the path between two end points. This paper presents a solution forfinding path between nodes in mobile ad hoc network. Termite is an innovative algorithm for packetrouting in communication networks. Termite is an adaptive, distributed, mobile-agents-based algorithmwhich was inspired by recent work on the ant colony metaphor. According to this algorithm, a group ofmobile agents (or artificial termites build paths between pair of nodes; exploring the networkconcurrently and exchanging obtained information to update the routing tables. Some of the parametersused to evaluate its performance are packet delays and throughput. The results of this algorithm showsbetter throughput as compared to existing algorithms. So, Termite algorithm is a promising alternativefor routing of data in commercial networks.

  9. Magnetic routing of light-induced waveguides

    Science.gov (United States)

    Izdebskaya, Yana; Shvedov, Vladlen; Assanto, Gaetano; Krolikowski, Wieslaw

    2017-01-01

    Among photofunctional materials that can be employed to control the propagation of light by modifying their properties, soft dielectrics such as nematic liquid crystals (NLCs) stand out for their large all-optical response. Through reorientation, the molecular distribution of NLCs can be modified by the electric field of light, permitting functional operations and supporting self-localized light beams or spatial optical solitons. To date, the generation and routing of such solitons have been limited by the boundary conditions employed to tailor the properties of NLCs in planar cells or capillaries. Here we report on spatial solitons in bulk NLCs with no lateral anchoring, where the application of an external magnetic field effectively controls the direction of propagation and the angular steering of the self-trapped wavepackets. Our results entail a completely new approach to the routing of self-localized beams and light-induced waveguides in three dimensions, without the usual limitations imposed by transverse boundary conditions. PMID:28198374

  10. Green-Aware Routing in GMPLS Networks

    DEFF Research Database (Denmark)

    Wang, Jiayuan; Ruepp, Sarah Renée; Fagertun, Anna Manolova

    2012-01-01

    The increasing amount of traffic in the Internet has been accommodated by the exponential growth of bandwidth provided by the optical networks technologies. However, such a growth has been also accompanied by an increase in the energy consumption and the concomitant green house gases (GHG......) emissions. Despite the efforts for improving energy efficiency in silicon technologies and network designs, the large energy consumption still poses challenges for the future development of Internet. In this paper, we propose an extension of the Open Shortest Path First - Traffic Engineering (OSPF......-TE) protocol and a greenaware routing and wavelength assignment (RWA) algorithm for minimizing the GHG emissions by routing connection requests through green network elements (NE). The network behavior and the performance of the algorithm are analyzed through simulations under different scenarios, and results...

  11. Chemical Routes to Colloidal Chalcogenide Nanosheets

    Energy Technology Data Exchange (ETDEWEB)

    Schaak, Raymond E. [Pennsylvania State Univ., University Park, PA (United States)

    2014-11-25

    This project began with an emphasis on developing new low-­temperature synthetic routes to intermetallic alloys in order to advance the synthesis and processing science of superconducting materials, as well as to potentially discover new materials that would be inaccessible using more traditional higher-­temperature methods. Our initial target materials, chosen as model systems for developing new low-­temperature solution-­based synthetic platforms, were based on well known superconducting alloys, including Nb3M (M = Ga, Ge, Sn), Bi-­M (M = In, Cu), and MgCNi3. Several key, fundamental synthetic challenges that underpinned the formation of these materials using solution chemistry routes were identified and investigated.

  12. Fund allocation using capacitated vehicle routing problem

    Science.gov (United States)

    Mamat, Nur Jumaadzan Zaleha; Jaaman, Saiful Hafizah; Ahmad, Rokiah Rozita; Darus, Maslina

    2014-09-01

    In investment fund allocation, it is unwise for an investor to distribute his fund into several assets simultaneously due to economic reasons. One solution is to allocate the fund into a particular asset at a time in a sequence that will either maximize returns or minimize risks depending on the investor's objective. The vehicle routing problem (VRP) provides an avenue to this issue. VRP answers the question on how to efficiently use the available fleet of vehicles to meet a given service demand, subjected to a set of operational requirements. This paper proposes an idea of using capacitated vehicle routing problem (CVRP) to optimize investment fund allocation by employing data of selected stocks in the FTSE Bursa Malaysia. Results suggest that CRVP can be applied to solve the issue of investment fund allocation and increase the investor's profit.

  13. Pedestrian Route Choice by Iterated Equilibrium Search

    CERN Document Server

    Kretz, Tobias; Hofsäß, Ingmar

    2014-01-01

    In vehicular traffic planning it is a long standing problem how to assign demand such on the available model of a road network that an equilibrium with regard to travel time or generalized costs is realized. For pedestrian traffic this question can be asked as well. However, as the infrastructure of pedestrian dynamics is not a network (a graph), but two-dimensional, there is in principle an infinitely large set of routes. As a consequence none of the iterating assignment methods developed for road traffic can be applied for pedestrians. In this contribution a method to overcome this problem is briefly summarized and applied with an example geometry which as a result is enhanced with routes with intermediate destination areas of certain shape. The enhanced geometry is used in some exemplary assignment calculations.

  14. Maritime route of colonization of Europe

    Science.gov (United States)

    Paschou, Peristera; Drineas, Petros; Yannaki, Evangelia; Razou, Anna; Kanaki, Katerina; Tsetsos, Fotis; Padmanabhuni, Shanmukha Sampath; Michalodimitrakis, Manolis; Renda, Maria C.; Pavlovic, Sonja; Anagnostopoulos, Achilles; Stamatoyannopoulos, John A.; Kidd, Kenneth K.; Stamatoyannopoulos, George

    2014-01-01

    The Neolithic populations, which colonized Europe approximately 9,000 y ago, presumably migrated from Near East to Anatolia and from there to Central Europe through Thrace and the Balkans. An alternative route would have been island hopping across the Southern European coast. To test this hypothesis, we analyzed genome-wide DNA polymorphisms on populations bordering the Mediterranean coast and from Anatolia and mainland Europe. We observe a striking structure correlating genes with geography around the Mediterranean Sea with characteristic east to west clines of gene flow. Using population network analysis, we also find that the gene flow from Anatolia to Europe was through Dodecanese, Crete, and the Southern European coast, compatible with the hypothesis that a maritime coastal route was mainly used for the migration of Neolithic farmers to Europe. PMID:24927591

  15. Routing of individual polymers in designed patterns

    DEFF Research Database (Denmark)

    Knudsen, Jakob Bach; Liu, Lei; Kodal, Anne Louise Bank

    2015-01-01

    Synthetic polymers are ubiquitous in the modern world, but our ability to exert control over the molecular conformation of individual polymers is very limited. In particular, although the programmable self-assembly of oligonucleotides and proteins into artificial nanostructures has been...... demonstrated, we currently lack the tools to handle other types of synthetic polymers individually and thus the ability to utilize and study their single-molecule properties. Here we show that synthetic polymer wires containing short oligonucleotides that extend from each repeat can be made to assemble...... into arbitrary routings. The wires, which can be more than 200 nm in length, are soft and bendable, and the DNA strands allow individual polymers to self-assemble into predesigned routings on both two- and three-dimensional DNA origami templates. The polymers are conjugated and potentially conducting, and could...

  16. Application of Harmony Search to Vehicle Routing

    Directory of Open Access Journals (Sweden)

    Zong W.  Geem

    2005-01-01

    Full Text Available A phenomenon-inspired meta-heuristic algorithm, harmony search, imitating music improvisation process, is introduced and applied to vehicle routing problem, then compared with one of the popular evolutionary algorithms, genetic algorithm. The harmony search algorithm conceptualized a group of musicians together trying to search for better state of harmony. This algorithm was applied to a test traffic network composed of one bus depot, one school and ten bus stops with demand by commuting students. This school bus routing example is a multi-objective problem to minimize both the number of operating buses and the total travel time of all buses while satisfying bus capacity and time window constraints. Harmony search could find good solution within the reasonable amount of time and computation.

  17. Advanced routing protocols for wireless networks

    CERN Document Server

    Campista , Miguel Elias Mitre

    2014-01-01

    This text introduces the principles of routing protocols and metrics as they affect wireless networking environments, specifically in urban areas. Timely because of the recent rise in small city life, this topic includes the consideration of ad hoc, mesh, vehicular, sensor, and delay tolerant networks. These approaches are each unique, and author Miguel Mitre Campista provides a thorough, but accessible, explanation of their individual characteristics for engineers, computer scientists, IT professionals, and curious Internet users.

  18. Deterministic nanoassembly: Neutral or plasma route?

    Science.gov (United States)

    Levchenko, I.; Ostrikov, K.; Keidar, M.; Xu, S.

    2006-07-01

    It is shown that, owing to selective delivery of ionic and neutral building blocks directly from the ionized gas phase and via surface migration, plasma environments offer a better deal of deterministic synthesis of ordered nanoassemblies compared to thermal chemical vapor deposition. The results of hybrid Monte Carlo (gas phase) and adatom self-organization (surface) simulation suggest that higher aspect ratios and better size and pattern uniformity of carbon nanotip microemitters can be achieved via the plasma route.

  19. Enabling Routes as Context in Mobile Services

    DEFF Research Database (Denmark)

    Brilingaite, Agne; Jensen, Christian Søndergaard; Zokaite, Nora

    2004-01-01

    With the continuing advances in wireless communications, geo-positioning, and portable electronics, an infrastructure is emerging that enables the delivery of on-line, location-enabled services to very large numbers of mobile users. A typical usage situation for mobile services is one characterized...... along with their usage patterns and that makes the accumulated routes available to services. Experiences from using the component with real GPS logs are reported....

  20. Spatial placement of state cycling routes

    OpenAIRE

    Milovanović, Klemen

    2009-01-01

    The national strategy and the traffic policy stimulate the development of unmotorized traffic, cycling infrastructure and the use of bicycles wherever possible. Regarding state interests, traffic engineer expert opinion and community involvment, the first draft of state cycling routes network was presented. Due to the document's merely informative nature, detailed spatial palacement studies are necessary. The main object of this Graduation Thesis is to define a detailed course,...

  1. Dynamic Routing of Short Transfer Baggage

    OpenAIRE

    2010-01-01

    We consider a variant of the Vehicle Routing Problem that arises in airports when transporting baggage for passengers with connecting flights. Each bag can be delivered in two locations with disjunctive time windows. The task is to define multiple trips for the vehicles in order to deliver bags that arrive continuously during the day. We present an IP model of the problem and describe the problem as a case study from a real life setting. We present a weighted greedy algorithm for dispatching ...

  2. Routing and advanced display technologies within STOMPM

    Science.gov (United States)

    Mittu, Ranjeev; Uhlmann, Jeffrey K.; McCune, Justin

    1998-08-01

    This paper will discuss research conducted at the Naval Research Laboratory in the area of automated routing, advanced 3D displays and novel interface techniques for interacting with those displays. This research has culminated in the development of the strike optimized mission planing module (STOMPM). The STOMPM testbed incorporates new technologies/results in the aforementioned areas to address the deficiencies in current systems and advance the state of the art in military planing systems.

  3. Efficient routing mechanisms for Dragonfly networks

    OpenAIRE

    Garcia M.; Vallejo E.; Beivide R.; Odriozola M.; Valero M.

    2013-01-01

    High-radix hierarchical networks are cost-effective topologies for large scale computers. In such networks, routers are organized in super nodes, with local and global interconnections. These networks, known as Dragonflies, outperform traditional topologies such as multi-trees or tori, in cost and scalability. However, depending on the traffic pattern, network congestion can lead to degraded performance. Misrouting (non-minimal routing) can be employed to avoid saturated global or local links...

  4. Congestion Free Routing in Adhoc Networks

    Directory of Open Access Journals (Sweden)

    V. Sankaranarayanan

    2012-01-01

    Full Text Available Problem statement: A Mobile Ad-Hoc Network (MANET is a temporary network; the mobile devices in an ad-hoc network are communicating through wireless links without any pre-existing infrastructure. The one major problem of this network is network congestion, it may take place at any intermediate nodes when data packets are traveling from source to destination. The major problems of congestion or high data loss, increasing End to End and retransmission packets which affects the overall network performance. The main goal of congestion control is to effectively utilize the existing network resources and maintain the network load below the capacity. Approach: This study presents the Congestion Free Routing in Adhoc networks (CFR, based on dynamically estimated mechanism to monitor network congestion by calculating the average queue length at the node level. While using the average queue length, the nodes’ congestion status divided into the three zones (safe zone, likely to be congested zone and congested zone. CFR utilizes the non-congested neighbors and initiates route discovery mechanism to discover a congestion free route between source and destination. This path becomes a core path between source and destination. To maintain the congestion free status, the nodes which are helping data packet transmission periodically calculate their congestion status at the node level. When a core node is noticed that it fell in to likely to congested zone and alerts to its neighbors. The predecessor core path node is aware of this situation and initiates an alternate path discovery mechanism to a destination. Finally it discovers a new congestion free route to the destination. Results: The assessment between CFR and AODV was conducted by using the Ns-2 simulator. The simulation results confirmed that the CFR improved packet delivery ratio, reduction of End to End delay and control packets. Conclusion: Our proposed technique solved the congestion problems in a

  5. An approximate algorithm for solving the watchman route problem

    NARCIS (Netherlands)

    Li, Fajie; Klette, Reinhard; Sommer, G; Klette, R

    2008-01-01

    The watchman route problem (WRP) was first introduced in 1988 and is defined as follows: How to calculate a shortest route completely contained inside a simple polygon such that any point inside this polygon is visible from at least one point on the route? So far the best known result for the WRP is

  6. 14 CFR 121.113 - Area and route requirements: General.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Area and route requirements: General. 121... OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Approval of Areas and Routes for Supplemental Operations § 121.113 Area and route requirements: General. (a) Each certificate holder...

  7. Optimum Route Planning and Scheduling for Unmanned Aerial Vehicles

    Science.gov (United States)

    2008-12-01

    Vehicle Routing Problem , VRP 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT Unclassified 18. SECURITY CLASSIFICATION OF THIS PAGE...23 B. VEHICLE ROUTING PROBLEM ........................................................ 26 C. ORIENTEERING PROBLEM AND PRIZE...Team Orienteering Problem TSP Traveling Salesman Problem VRP Vehicle Routing Problem VRPPD VRP with Pick-Up And Delivering VRPTW VRP with Time

  8. A Survey on Underwater Acoustic Sensor Network Routing Protocols.

    Science.gov (United States)

    Li, Ning; Martínez, José-Fernán; Meneses Chaus, Juan Manuel; Eckert, Martina

    2016-01-01

    Underwater acoustic sensor networks (UASNs) have become more and more important in ocean exploration applications, such as ocean monitoring, pollution detection, ocean resource management, underwater device maintenance, etc. In underwater acoustic sensor networks, since the routing protocol guarantees reliable and effective data transmission from the source node to the destination node, routing protocol design is an attractive topic for researchers. There are many routing algorithms have been proposed in recent years. To present the current state of development of UASN routing protocols, we review herein the UASN routing protocol designs reported in recent years. In this paper, all the routing protocols have been classified into different groups according to their characteristics and routing algorithms, such as the non-cross-layer design routing protocol, the traditional cross-layer design routing protocol, and the intelligent algorithm based routing protocol. This is also the first paper that introduces intelligent algorithm-based UASN routing protocols. In addition, in this paper, we investigate the development trends of UASN routing protocols, which can provide researchers with clear and direct insights for further research.

  9. 49 CFR 236.302 - Track circuits and route locking.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Track circuits and route locking. 236.302 Section 236.302 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... Standards § 236.302 Track circuits and route locking. Track circuits and route locking shall be provided...

  10. 77 FR 54805 - Revocation of Jet Route J-528; WA

    Science.gov (United States)

    2012-09-06

    ... Federal Aviation Administration 14 CFR Part 71 RIN 2120-AA66 Revocation of Jet Route J-528; WA AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action removes Jet Route J...., Washington, DC 20591; telephone: (202) 267-8783. SUPPLEMENTARY INFORMATION: Background Jet Route J-528...

  11. 75 FR 66344 - Amendment of Jet Route J-93; CA

    Science.gov (United States)

    2010-10-28

    ... Federal Aviation Administration 14 CFR Part 71 RIN 2120-AA66 Amendment of Jet Route J-93; CA AGENCY... action proposes to amend Jet Route J-93 in California between the Julian VHF Omnidirectional Radio Range... is necessary to realign Jet Route J-93 with the revised location of the Penasco VOR. The Proposal...

  12. Simulated Annealing Technique for Routing in a Rectangular Mesh Network

    Directory of Open Access Journals (Sweden)

    Noraziah Adzhar

    2014-01-01

    Full Text Available In the process of automatic design for printed circuit boards (PCBs, the phase following cell placement is routing. On the other hand, routing process is a notoriously difficult problem, and even the simplest routing problem which consists of a set of two-pin nets is known to be NP-complete. In this research, our routing region is first tessellated into a uniform Nx×Ny array of square cells. The ultimate goal for a routing problem is to achieve complete automatic routing with minimal need for any manual intervention. Therefore, shortest path for all connections needs to be established. While classical Dijkstra’s algorithm guarantees to find shortest path for a single net, each routed net will form obstacles for later paths. This will add complexities to route later nets and make its routing longer than the optimal path or sometimes impossible to complete. Today’s sequential routing often applies heuristic method to further refine the solution. Through this process, all nets will be rerouted in different order to improve the quality of routing. Because of this, we are motivated to apply simulated annealing, one of the metaheuristic methods to our routing model to produce better candidates of sequence.

  13. Multipath Routing with Erasure Coding for Wireless Sensor Networks

    NARCIS (Netherlands)

    Wu, Jian; Dulman, Stefan; Havinga, Paul; Nieberg, Tim

    2004-01-01

    Multipath routing algorithm in wireless sensor networks (WSN) increase the reliability of the system at the cost of significantly increased traffic. This paper introduces a splitted multipath routing scheme to improve the reliability of data routing in WSN by keeping the traffic at a low level. Our

  14. An energy efficient multipath routing algorithm for wireless sensor networks

    NARCIS (Netherlands)

    Dulman, Stefan; Wu, Jian; Havinga, Paul

    2003-01-01

    In this paper we introduce a new routing algorithm for wireless sensor networks. The aim of this algorithm is to provide on-demand multiple disjoint paths between a data source and a destination. Our Multipath On-Demand Routing Algorithm (MDR) improves the reliability of data routing in a wireless m

  15. Continental river routing model for water resources applications

    Science.gov (United States)

    Mizukami, N.; Clark, M. P.; Sampson, K. M.

    2015-12-01

    This presentation describes a stand-alone runoff routing tool, mizuRoute, which post-processes runoff outputs from any distributed hydrologic model or land surface model to produce spatially distributed streamflow at various spatial scales from headwater basins to continental-wide river systems. The tool utilizes vector-based river network data, which includes river segment lines and the associated drainage basin polygons. Streamflow estimates at any desired location in the river network can be easily extracted from the output of mizuRoute. The first step of the routing tool is hillslope routing, which uses a gamma distribution to construct a unit-hydrograph that represents the transport of runoff from a hillslope to an outlet of the catchment. The second step is river channel routing, which is performed with one of two routing scheme options: a) the kinematic wave tracking (KWT) routing procedure; and 2) the impulse response function - unit hydrograph (IRF-UH) routing procedure. This presentation demonstrate mizuRoute's capabilities to produce spatially distributed streamflow simulations based on the river network data from the United States Geological Survey (USGS) Geospatial Fabric (GF) dataset, which contains over 54000 river segments across the contiguous United States (CONUS). We routed ensemble of 150 years runoff simulated with Variable Infiltration Capacity Model forced by climate data from Coupled Model Intercomparison Project Phase 5. A brief analysis of the routing model parameter sensitivity is also presented.

  16. A Survey on Underwater Acoustic Sensor Network Routing Protocols

    Science.gov (United States)

    Li, Ning; Martínez, José-Fernán; Meneses Chaus, Juan Manuel; Eckert, Martina

    2016-01-01

    Underwater acoustic sensor networks (UASNs) have become more and more important in ocean exploration applications, such as ocean monitoring, pollution detection, ocean resource management, underwater device maintenance, etc. In underwater acoustic sensor networks, since the routing protocol guarantees reliable and effective data transmission from the source node to the destination node, routing protocol design is an attractive topic for researchers. There are many routing algorithms have been proposed in recent years. To present the current state of development of UASN routing protocols, we review herein the UASN routing protocol designs reported in recent years. In this paper, all the routing protocols have been classified into different groups according to their characteristics and routing algorithms, such as the non-cross-layer design routing protocol, the traditional cross-layer design routing protocol, and the intelligent algorithm based routing protocol. This is also the first paper that introduces intelligent algorithm-based UASN routing protocols. In addition, in this paper, we investigate the development trends of UASN routing protocols, which can provide researchers with clear and direct insights for further research. PMID:27011193

  17. A Survey on Underwater Acoustic Sensor Network Routing Protocols

    Directory of Open Access Journals (Sweden)

    Ning Li

    2016-03-01

    Full Text Available Underwater acoustic sensor networks (UASNs have become more and more important in ocean exploration applications, such as ocean monitoring, pollution detection, ocean resource management, underwater device maintenance, etc. In underwater acoustic sensor networks, since the routing protocol guarantees reliable and effective data transmission from the source node to the destination node, routing protocol design is an attractive topic for researchers. There are many routing algorithms have been proposed in recent years. To present the current state of development of UASN routing protocols, we review herein the UASN routing protocol designs reported in recent years. In this paper, all the routing protocols have been classified into different groups according to their characteristics and routing algorithms, such as the non-cross-layer design routing protocol, the traditional cross-layer design routing protocol, and the intelligent algorithm based routing protocol. This is also the first paper that introduces intelligent algorithm-based UASN routing protocols. In addition, in this paper, we investigate the development trends of UASN routing protocols, which can provide researchers with clear and direct insights for further research.

  18. Secure multipath routing and data transmission in MANET

    DEFF Research Database (Denmark)

    Banoth, Rajkumar; Narsimha, Gugulothu

    2016-01-01

    In mobile ad hoc network (MANET), providing security during multipath routing protocol and during the data transmission with the multiple routes is a challenging task. For this, in this paper, we propose a secure multipath routing and data transmission in which RREQ packets are signed using digital...

  19. Dynamic Equilibrium Assignment Convergence by En-route Flow Smoothing

    NARCIS (Netherlands)

    Pel, A.J.; Bliemer, M.C.J.; Hoogendoorn, S.P.

    2010-01-01

    An essential feature in many dynamic traffic assignment (DTA) models used for planning purposes is to compute the (dynamic) equilibrium assignment, where travellers follow user-optimal routes, leading to minimal experienced route travel times. To compute these time-varying route flows in the equilib

  20. Tour Route Multiobjective Optimization Design Based on the Tourist Satisfaction

    Directory of Open Access Journals (Sweden)

    Yan Han

    2014-01-01

    Full Text Available The question prompted is how to design the tour route to make the tourists get the maximum satisfactions considering the tourists’ demand. The influence factors of the tour route choices of tourists were analyzed and tourists’ behavior characteristics and psychological preferences were regarded as the important influence factors based on the tourist behavioral theories. A questionnaire of tourists’ tour route information and satisfaction degree was carried out. Some information about the scene spot and tourists demand and tour behaviors characteristic such as visit frequency, number of attractions visited was obtained and analyzed. Based on the convey datum, tour routes multiobjective optimization functions were prompted for the tour route design regarding the maximum satisfaction and the minimum tour distance as the optimal objective. The available routes are listed and categorized. Based on the particle swarm optimization model, the priorities of the tour route are calculated and finally the suggestion depth tour route and quick route tour routes are given considering the different tour demands of tourists. The results can offer constructive suggestions on how to design tour routes on the part of tourism enterprises and how to choose a proper tour route on the part of tourists.

  1. An improved AODV routing protocol based on tower structure

    Directory of Open Access Journals (Sweden)

    Li Yong Qiang

    2016-01-01

    Full Text Available The paper proposed a new routing protocol(IAODV based on tower structure in the Ad Hoc network for the problem which Location Routing Protocol need hardware and Complex algorithm. By the simulation, The complexity of the new routing protocol is reduced without reducing the performance of the network.

  2. QoS Routing in Smart Grid

    CERN Document Server

    Li, Husheng

    2010-01-01

    Smart grid is an emerging technology which is able to control the power load via price signaling. The communication between the power supplier and power customers is a key issue in smart grid. Performance degradation like delay or outage may cause significant impact on the stability of the pricing based control and thus the reward of smart grid. Therefore, a QoS mechanism is proposed for the communication system in smart grid, which incorporates the derivation of QoS requirement and applies QoS routing in the communication network. For deriving the QoS requirement, the dynamics of power load and the load-price mapping are studied. The corresponding impacts of different QoS metrics like delay are analyzed. Then, the QoS is derived via an optimization problem that maximizes the total revenue. Based on the derived QoS requirement, a simple greedy QoS routing algorithm is proposed for the requirement of high speed routing in smart grid. It is also proven that the proposed greedy algorithm is a $K$-approximation. ...

  3. Collective Intelligence, Data Routing and Braess' Paradox

    CERN Document Server

    Tumer, K; 10.1613/jair.995

    2011-01-01

    We consider the problem of designing the the utility functions of the utility-maximizing agents in a multi-agent system so that they work synergistically to maximize a global utility. The particular problem domain we explore is the control of network routing by placing agents on all the routers in the network. Conventional approaches to this task have the agents all use the Ideal Shortest Path routing Algorithm (ISPA). We demonstrate that in many cases, due to the side-effects of one agent's actions on another agent's performance, having agents use ISPA's is suboptimal as far as global aggregate cost is concerned, even when they are only used to route infinitesimally small amounts of traffic. The utility functions of the individual agents are not "aligned" with the global utility, intuitively speaking. As a particular example of this we present an instance of Braess' paradox in which adding new links to a network whose agents all use the ISPA results in a decrease in overall throughput. We also demonstrate th...

  4. Royal Danish Air Force. Air Operations Doctrine

    DEFF Research Database (Denmark)

    Nørby, Søren

    This brief examines the development of the first Danish Air Force Air Operations Doctrine, which was officially commissioned in October 1997 and remained in effect until 2010. The development of a Danish air power doctrine was heavily influenced by the work of Colonel John Warden (USAF), both...... through his book ”The Air Campaign” and his subsequent planning of the air campaign against Iraq in 1990-1991. Warden’s ideas came to Denmark and the Danish Air Force by way of Danish Air Force students attending the United States Air Force Air University in Alabama, USA. Back in Denmark, graduates from...... the Air University inspired a small number of passionate airmen, who then wrote the Danish Air Operations Doctrine. The process was supported by the Air Force Tactical Command, which found that the work dovetailed perfectly with the transformation process that the Danish Air Force was in the midst...

  5. EXTENDED DYNAMIC SOURCE ROUTING PROTOCOL FOR AD HOC NETWORK

    Directory of Open Access Journals (Sweden)

    Puja Kumari Sharma

    2012-07-01

    Full Text Available MANET is a collection of self-configurable mobile nodes. Several routing protocols are proposed for ad hoc network among which DSR and AODV On demand routing protocols are mostly used. Existing Dynamic source routing protocol is not suitable for large network because packet size gets increased according to the number of nodes travelled by route discovery packet. In this paper, extended DSR routing protocol is proposed to eliminate the above limitation of existing DSR. Proposed protocol will be suitable for small and large both types of networks.

  6. Delay Tolerant Network Routing Nature – A Study

    Directory of Open Access Journals (Sweden)

    V. Prema Tulasi

    2014-04-01

    Full Text Available Delay-Tolerant network (DTN is a network in which no simultaneous end-to-end path exists. And the messages delivered in the DTN usually have large delivery latency due to network partition. These special characteristics make DTN routing a challenging problem. For this purpose, we updated the shortest path based routing algorithms using conditional intermeeting times and proposed to route the messages over conditional shortest paths. This proposes Conditional Shortest Path Routing (CSPR protocol that route the messages over conditional shortest paths in which the cost of links between nodes is defined by conditional intermeeting times rather than the conventional intermeeting times.

  7. Routing Protocol Design and Performance Optimization in Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    Zhenguo Wu

    2013-10-01

    Full Text Available Routing protocol is an important issue in cognitive radio networks. This paper explored the issues and challenges of routing protocol in cognitive radio network from five aspects: hidden terminal, exposed terminal, deafness, cross-layer design, and topology. The existed protocols are classified by the metrics: the establishment of active routing, cross-layer routing, and network performance indicators. Focusing on analyzing performance of routing protocols and design optimized schemes in cognitive radio networks, the advantage and disadvantage of related work were discussed in detail.

  8. Adaptive swarm-based routing in communication networks

    Institute of Scientific and Technical Information of China (English)

    吕勇; 赵光宙; 苏凡军; 历小润

    2004-01-01

    Swarm intelligence inspired by the social behavior of ants boasts a number of attractive features, including adaptation, robustness and distributed, decentralized nature, which are well suited for routing in modern communication networks. This paper describes an adaptive swarm-based routing algorithm that increases convergence speed, reduces routing instabilities and oscillations by using a novel variation of reinforcement learning and a technique called momentum.Experiment on the dynamic network showed that adaptive swarm-based routing learns the optimum routing in terms of convergence speed and average packet latency.

  9. Adaptive swarm-based routing in communication networks

    Institute of Scientific and Technical Information of China (English)

    吕勇; 赵光宙; 苏凡军; 历小润

    2004-01-01

    Swarm intelligence inspired by the social behavior of ants boasts a number of attractive features,including adaptation,robustness and distributed,decentralized nature,which are well suited for routing in modern communication networks.This paper describes an adaptive swarm-based routing algorithm that increases convergence speed,reduces routing instabilities and oscillations by using a novel variation of reinforcement learning and a technique called momentum.Experiment on the dynamic network showed that adaptive swarm-based routing learns the optimum routing in terms of convergence speed and average packet latency.

  10. Mobility Tolerant Firework Routing for Improving Reachability in MANETs

    Directory of Open Access Journals (Sweden)

    Gen Motoyoshi

    2014-03-01

    Full Text Available In this paper, we investigate our mobility-assisted and adaptive broadcast routing mechanism, called Mobility Tolerant Firework Routing (MTFR, which utilizes the concept of potentials for routing and improves node reachability, especially in situations with high mobility, by including a broadcast mechanism. We perform detailed evaluations by simulations in a mobile environment and demonstrate the advantages of MTFR over conventional potential-based routing. In particular, we show that MTFR produces better reachability in many aspects at the expense of a small additional transmission delay and intermediate traffic overhead, making MTFR a promising routing protocol and feasible for future mobile Internet infrastructures.

  11. Efficiency of choice set generation methods for bicycle routes

    DEFF Research Database (Denmark)

    Halldórsdóttir, Katrín; Rieser-Schussler, Nadine; Axhausen, Kay W.

    2014-01-01

    The current study analyses the efficiency of choice set generation methods for bicycle routes and proposes the extension of cost functions to bicycle-oriented factors not limited to distance and time. Three choice set generation methods for route choice were examined in their ability to generate...... relevant and heterogeneous routes: doubly stochastic generation function, breadth first search on link elimination, and branch & bound algorithm. Efficiency of the methods was evaluated for a high-resolution network by comparing the performances with four multi-attribute cost functions accounting...... generated realistic routes, while the former outperformed in computation cost and the latter produced more heterogeneous routes....

  12. The competitive landscape of air transport in Europe

    NARCIS (Netherlands)

    Lieshout, R.; Malighetti, P.; Redondi, R.; Burghouwt, G.

    2016-01-01

    Competition between airlines and airports increased significantly since the deregulation of the intra-European air transport market in 1997. The passenger has a wider choice in terms of routings and departure airports than twenty-five years ago and pays a lower price. In this paper we investigate in

  13. On Performance Modeling of Ad Hoc Routing Protocols

    Directory of Open Access Journals (Sweden)

    Khayam SyedAli

    2010-01-01

    Full Text Available Simulation studies have been the predominant method of evaluating ad hoc routing algorithms. Despite their wide use and merits, simulations are generally time consuming. Furthermore, several prominent ad hoc simulations report inconsistent and unrepeatable results. We, therefore, argue that simulation-based evaluation of ad hoc routing protocols should be complemented with mathematical verification and comparison. In this paper, we propose a performance evaluation framework that can be used to model two key performance metrics of an ad hoc routing algorithm, namely, routing overhead and route optimality. We also evaluate derivatives of the two metrics, namely, total energy consumption and route discovery latency. Using the proposed framework, we evaluate the performance of four prominent ad hoc routing algorithms: DSDV, DSR, AODV-LL, and Gossiping. We show that the modeled metrics not only allow unbiased performance comparison but also provide interesting insight about the impact of different parameters on the behavior of these protocols.

  14. Our Brothers' Keepers: Secure Routing with High Performance

    CERN Document Server

    Brodsky, Alex

    2008-01-01

    The Trinity (Brodsky et al., 2007) spam classification system is based on a distributed hash table that is implemented using a structured peer-to-peer overlay. Such an overlay must be capable of processing hundreds of messages per second, and must be able to route messages to their destination even in the presence of failures and malicious peers that misroute packets or inject fraudulent routing information into the system. Typically there is tension between the requirements to route messages securely and efficiently in the overlay. We describe a secure and efficient routing extension that we developed within the I3 (Stoica et al. 2004) implementation of the Chord (Stoica et al. 2001) overlay. Secure routing is accomplished through several complementary approaches: First, peers in close proximity form overlapping groups that police themselves to identify and mitigate fraudulent routing information. Second, a form of random routing solves the problem of entire packet flows passing through a malicious peer. Thi...

  15. BCR Routing for Intermittently Connected Mobile Ad hoc Networks

    Directory of Open Access Journals (Sweden)

    S. RAMESH

    2014-03-01

    Full Text Available The Wireless and the Mobile Networks appear to provide a wide range of applications. Following these, the Mobile Ad hoc Networks (MANET aid in wide development of many applications. The achievement of the real world applications are attained through effective routing. The Intermittently Connected Mobile Ad hoc Network (ICMANET is a sparse network where a full connectivity is never possible. ICMANET is a disconnected MANET and is also a Delay Tolerant Network (DTN that sustains for higher delays. The routing in a disseminated network is a difficult task. A new routing scheme called Bee Colony Routing (BCR is been proposed with a motto of achieving optimal result in delivering the data packet towards the destined node. BCR is proposed with the basis of Bee Colony Optimization technique (BCO. The routing in ICMNAET is done by means of Bee routing protocol. This paper enchants a novel routing methodology for data transmission in ICMANET.

  16. MiniTE: data acquisition routing for wireless sensor networks

    Institute of Scientific and Technical Information of China (English)

    LI Wen-feng; WANG Ru-chuan; SUN Li-juan

    2009-01-01

    Routing is one of the most important supporting parts in wireless sensor networks (WSNs) application that directly affects the application efficiency. Routing time and energy consumption are two major factors used to evaluate WSNs routing. This article proposes a minimum routing time and energy consumption (MiniTE) routing, which can ensure feasibility of the routing protocol both in routing time and energy consumption. Based on the MiniTE, WSNs can be partitioned into different regions according to the received signal strength indication (RSSI). Messages are sent by nodes in the region to their parent node and again up to their parent node until finally to the sink node. Theoretic evaluation and simulation results are given to verify the features of the protocol.

  17. REDUCING BURST PACKET LOSS THROUGH ROUTE-FREE FORWARDING

    Institute of Scientific and Technical Information of China (English)

    Ma Hailong; Guo Yunfei; Cheng Dongnian; Zhang Jianwei

    2010-01-01

    It is well known that today's inter-domain routing protocol,Border Gateway Protocol (BGP),converges slowly during network failures. Due to the distribution nature of Internet routing decisions and the rate-limiting timer Minimum Route Advertisement Interval (MRAI) of BGP,unavoidable convergence latency is introduced in reaction to network changes. During the period of convergence temporarily routing table inconsistencies cause short-term routing blackholes and loops which result in widespread temporary burst packet loss. In this paper,we present ROute-Free Forwarding (ROFF) - a novel technique for packet delivering continuously during periods of convergence. With slightly modifications on IP packet header and BGP,route loops and blackholes can be avoided. Our preliminary evaluation demonstrates that ROFF succeeds in reducing the number of Autonomous Systems (ASes) which experience burst packet loss and the duration of packet loss.

  18. Great Ellipse Route Planning Based on Space Vector

    Directory of Open Access Journals (Sweden)

    LIU Wenchao

    2015-07-01

    Full Text Available Aiming at the problem of navigation error caused by unified earth model in great circle route planning using sphere model and modern navigation equipment using ellipsoid mode, a method of great ellipse route planning based on space vector is studied. By using space vector algebra method, the vertex of great ellipse is solved directly, and description of great ellipse based on major-axis vector and minor-axis vector is presented. Then calculation formulas of great ellipse azimuth and distance are deduced using two basic vectors. Finally, algorithms of great ellipse route planning are studied, especially equal distance route planning algorithm based on Newton-Raphson(N-R method. Comparative examples show that the difference of route planning between great circle and great ellipse is significant, using algorithms of great ellipse route planning can eliminate the navigation error caused by the great circle route planning, and effectively improve the accuracy of navigation calculation.

  19. Specifying and Configuring Routing Policies of Relative AS in RPSL

    Institute of Scientific and Technical Information of China (English)

    夏登文; 石绥祥; 于戈

    2004-01-01

    Routing policies specification language (RPSL) allows a network operator to specify routing policies at various levels in the Internet hierarchy, for example at the autonomous system (AS) level. At the same time, policies can be specified with sufficient detail in RPSL so that the low level router configurations can be generated from them. This paper is a discussion on using the RPSL to describe routing policies of relative AS in the Internet routing registry (IRR). We first analyze the relationships between a pair of ASes, and then explain how to specify various relative AS routing policies in RPSL. At last, we show an example of configuring routing policies using RtConfig that is a tool developed by the Routing Arbiter Project (RAP).

  20. GSPEL - Air Filtration Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Evaluation capabilities for air filtration devices The Air Filtration Lab provides testing of air filtration devices to demonstrate and validate new or legacy system...

  1. Secure Routing and Identifying Hacking In P2p System

    Directory of Open Access Journals (Sweden)

    Gowsiga Subramaniam

    2014-08-01

    Full Text Available Packet forwarding is the procedure to route the packet from source to destination via routers. Getting the systems ip address in a LAN and decides the source, destination and the intermediate systems for our routing process. Using any database form the routing table with columns like source address, destination address and router addresses. After creating the routing table enters the ip address in the respective columns. As per this procedure by comparing ip addresses in the routing table the packet will be forward to next ip address. The ip addresses in the routing table, are the path selected by the user according to the respective path the packet will be forward and finally reach destination. Source generate a packet and forward to ip address which is in router ip as per in routing table. Source need to know whether the packet received by authenticated router or not thus each router send an acknowledgement packet to the source. Thus each and every router follows the same procedure to avoid unauthenticated router access in a routing process. As per acknowledgement received from each router source finds out the unauthenticated router access. As per security concern added the signature scheme in a routing process. Before send the packet, source generates the signature with peer ID of destination then forwards the packet to the ip address as per routing table. The packet will be decrypted only the system matched with the signature otherwise just forwards the packet to the next system. Tracer routing is to find out the unauthorized router access in a routing process. This is verifying by getting acknowledgment from each and every router in the routing process by a source. Then source compare the acknowledgement with the predefined routing table if any ip mismatch then it will be consider as unauthorized ip.

  2. Possible routes for lead accumulation in feral pigeons (Columba livia).

    Science.gov (United States)

    Nam, Dong-Ha; Lee, Doo-Pyo

    2006-10-01

    This study examined possible routes for lead (Pb) accumulation in resident pigeons collected from rural, urban, and four industrial sites in Korea. The accumulation pattern of Pb was comparable to the study sites. The highest Pb concentration was found in the bone, followed by kidney, liver, and lung of pigeons. Highest Pb residues in bones were found in urban (Seoul), and two industrial complex areas (Busan and Ulsan), which were about 15 times higher than rural area (Duckjuk island), and followed by Ansan and Yochon industrial areas. Regional Pb variations in liver, kidney, and lung tissues were also similar pattern with the bone Pb difference. These findings indicate that Pb accumulation in tissues of pigeons may be affected by the Pb exposure in their respective habitats. Crop contents and gizzard materials were investigated as representing the ingested items. No difference of Pb concentration was observed in major foods (maize and/or wheat) of crop contents in the study sites except Busan, whereas variations of Pb levels in gizzard materials were indicative of a similar pattern with tissue Pb differences. The Pb concentration in tissues of pigeons did not correspond well to the atmospheric Pb levels. With regard to possible Pb sources, ingested items especially materials present in the gizzard are important sources for Pb contamination to pigeons because Pb-containing sources may be expected to present in roadside particles, dusts, paint chips and building flakes. However, air Pb value being low may not affect significant as the regional variations in tissues of pigeons.

  3. FAA Air Traffic Control Operations Concepts. Volume 6. ARTCC (Air Route Traffic Control Center)/Host En Route Controllers. Change 1

    Science.gov (United States)

    1988-07-29

    8217 and (MinimumVectorAltitude) ’ MVA ’ and Holding Pattern_Airspace and (ProminentObject) *obstruction* O Task Analysis 0-8 DOT/FAA/AP-87-O1 (VOL #6) CHG 1...0 o A 1. 4 .2 . + DETEC T A P IL O T 02 A IRCRA FT PRO 8 , 17M (E .G . .HV POX IA , × XI X X EXCEPTIN BEACON CODE) 0209 .-~-’... VL’ v Al. 4.2. 8

  4. Air-to-Air Missile Vector Scoring

    Science.gov (United States)

    2012-03-22

    64 4.6. Unscented Kalman Filter Performance in Air-to-Air Missile Scor - ing Application with Continuous Velocity Dynamics Model (Tar- get...Filter Performance in Air-to-Air Missile Scor - ing Application with Continuous Velocity Dynamics Model (Tar- get Aircraft Executing a Vertical Climb...Kalman Filter Performance in Air-to-Air Missile Scor - ing Application with Continuous Velocity Dynamics Model (Tar- get Aircraft Non-maneuvering

  5. Enhanced Route Re-Construction Method for Associativity Based Routing Protocol for Mobile Ad hoc NETworks (MANET

    Directory of Open Access Journals (Sweden)

    Fawaz A.M. Masoud

    2006-01-01

    Full Text Available A mobile Ad-hoc NETwork (MANET is wireless network composed of mobile nodes that are dynamically and randomly located in such a manner that the interconnections between nodes are capable of changing on a continual basis. In order to facilitate communication within the network, a routing protocol is used to discover routes between nodes. The primary goal of such an ad-hoc network routing protocol is correct and efficient route establishment between a pair of nodes so that messages may be delivered in a timely manner. Route construction and maintenance should be done with a minimum of overhead and bandwidth consumption. The ABR is a source-initiated protocol and is working on the assumption of stable route from the source to the destination node. Maintenance for the route when the destination node moves will be performed in backtracking scheme starting from the immediate upstream node from the destination. If this process results in backtracking more than halfway to the source, it will discontinue and a new route request will be initiated from the source. In the case if the Source Node moves, then the Source Node will invoke a route reconstruction because the ABR is source-initiated protocol. This study presents an enhanced method for the route re-construction in case the source, the intermediate, or the destination node changes its location by giving more active role to the moving node in maintaining the established route.

  6. An easy route to make superhydrophobic surface

    Science.gov (United States)

    Panda, Kalpataru; Kumar, N.; Polaki, S. R.; Panigrahi, B. K.

    2012-06-01

    Superhydrophobic films with excellent flexibility have been fabricated on silicon surface, generated by means of a chemical galvanic cell route, within a short span of 10 sec. The results show a water contact angle of 155° (superhydrophobic) for the chemically modified silicon surface while it is 63° (hydrophilic) in pure silicon substrate. The surface roughness increases with well ordered protrusions after the chemical treatment. Surface roughness and low surface energy are ascribed for the superhydrophobic behavior of these chemically modified silicon surfaces.

  7. Approximation algorithms for some vehicle routing problems

    OpenAIRE

    Bazgan, Cristina; Hassin, Refael; Monnot, Jérôme

    2005-01-01

    We study vehicle routing problems with constraints on the distance traveled by each vehicle or on the number of vehicles. The objective is either to minimize the total distance traveled by vehicles or to minimize the number of vehicles used. We design constant differential approximation algorithms for kVRP. Note that, using the differential bound for METRIC 3VRP, we obtain the randomized standard ratio . This is an improvement of the best-known bound of 2 given by Haimovich et al. (Vehicle Ro...

  8. New Synthesis Route for PHD Polyols

    OpenAIRE

    Peshkov, Vladimir; Evtimova, Rozeta; Herzog, Michael; Behrendt, Gerhard

    2011-01-01

    The synthesis of polyurea dispersion polyols (PHD) was developed using a new route via depolymerization of polyurethane polyureas by a mixture of at least two glycols in the presence of a consumable catalyst, i. e. a secondary aliphatic amine. On this way such polyols were produced with a particle size distribution with a maximum in the 120 to 400 nanometer region with hydroxyl numbers of 180 to 300 mg KOH/g being optically clear and highly reactive. The exact adjustment of the ethylene oxide...

  9. Endocannabinoids, Related Compounds and Their Metabolic Routes

    Directory of Open Access Journals (Sweden)

    Filomena Fezza

    2014-10-01

    Full Text Available Endocannabinoids are lipid mediators able to bind to and activate cannabinoid receptors, the primary molecular targets responsible for the pharmacological effects of the Δ9-tetrahydrocannabinol. These bioactive lipids belong mainly to two classes of compounds: N-acylethanolamines and acylesters, being N-arachidonoylethanolamine (AEA and 2-arachidonoylglycerol (2-AG, respectively, their main representatives. During the last twenty years, an ever growing number of fatty acid derivatives (endocannabinoids and endocannabinoid-like compounds have been discovered and their activities biological is the subject of intense investigations. Here, the most recent advances, from a therapeutic point of view, on endocannabinoids, related compounds, and their metabolic routes will be reviewed.

  10. Endocannabinoids, related compounds and their metabolic routes.

    Science.gov (United States)

    Fezza, Filomena; Bari, Monica; Florio, Rita; Talamonti, Emanuela; Feole, Monica; Maccarrone, Mauro

    2014-10-24

    Endocannabinoids are lipid mediators able to bind to and activate cannabinoid receptors, the primary molecular targets responsible for the pharmacological effects of the Δ9-tetrahydrocannabinol. These bioactive lipids belong mainly to two classes of compounds: N-acylethanolamines and acylesters, being N-arachidonoylethanolamine (AEA) and 2-arachidonoylglycerol (2-AG), respectively, their main representatives. During the last twenty years, an ever growing number of fatty acid derivatives (endocannabinoids and endocannabinoid-like compounds) have been discovered and their activities biological is the subject of intense investigations. Here, the most recent advances, from a therapeutic point of view, on endocannabinoids, related compounds, and their metabolic routes will be reviewed.

  11. Travel Along The Long March Route

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>At the invi-tation of the China-Ja-pan Friendship Association(CJFA),the delegation for studying the Chinese peo-ple’s revolu-tionary wars(Long March delegation for short)orga-nized by the Japan Iskra In-dustry Compa-ny Ltd.came to China to travel along the route of the Red Army’s Long March in Si-chuan Province to learn the Chinese revo-lutionary spirit from October 25 to 31,2007.

  12. New soft chemical routes to ferroelectric materials

    OpenAIRE

    Babooram, Keshwaree (Vima)

    2005-01-01

    A new soft chemical route has been developed in the first part of this thesis for synthesis of relaxor ferroelec tric, (1 -~)Pb(Mg~~-,Nb~~~)O~-xPbTi0~ [(I -x)PMN-xPT] (x = 0.10, 0.35) ceramics. This polyethylene glycol-based method shows some very interesting features. It allows the sol-gel reactions to be performed at room temperature, eliminating reflux steps usually required in sol-gel processes. Moreover, it does not require excess amounts of lead starting material to compensate for lead ...

  13. The Route towards the ultimate network topology

    OpenAIRE

    Rodriguez, German

    2016-01-01

    In this talk I will try to summarize our quest for a realizable network topology that optimizes performance, cost, power consumption and partitionability. We have explored Fat Trees, Dragonflies, variations of dragonflies, Orthogonal Fat Trees, multi-layer HyperX's, Multi-layer Full Meshes and close-to Moore's (graph) bound topologies in an attempt to decide, with the best routing we could find, for a reasonable task-placement, and for a collection of workloads (synthetic and real-world), whi...

  14. Formation of nanocrystalline niobium carbide (NbC) with a convenient route at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Ma Jianhua [College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, Zhejiang 325027 (China); Nanomaterials and Chemistry Key Laboratory, Advanced Materials Research Center of Wenzhou, Wenzhou University, Wenzhou, Zhejiang 325027 (China)], E-mail: mjh820@ustc.edu; Wu Meining [College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, Zhejiang 325027 (China); Du Yihong [City College, Wenzhou University, Wenzhou, Zhejiang 325035 (China); Chen Suqin; Jin Wu; Fu Li; Yang Qiongyao; Wen Aifei [College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, Zhejiang 325027 (China)

    2009-05-05

    Nanocrystalline NbC has been prepared via a convenient route by the reaction of metallic magnesium powders with niobium pentoxide and basic magnesium carbonate in an autoclave at 550 deg. C. X-ray powder diffraction pattern indicated that the product was cubic niobium carbide, and the cell constant was a = 4.461 A. Transmission electron microscopy (TEM) image showed that it consisted of particles with an average size of about 30 nm in diameter. The product was also studied by BET and TGA. It had good thermal stability and oxidation resistance below 400 deg. C in air.

  15. An Investigation into the Advantages, Mechanisms, and Developmental Challenges of Scripted Mobile Routing

    Science.gov (United States)

    2008-03-01

    AODV ) routing protocol is designed to take advantage of prior knowledge of topology to improve...data exists, it updates the routing table. If not then it broadcasts RREQs like AODV routing protocol . Using this approach, S- AODV enjoys reduced... routing traffic and route discovery times. S- AODV is compared with Ad Hoc On-demand Distance Vector ( AODV ) routing protocol . S- AODV provides

  16. R9 Air Districts

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Region 9 Air Districts layer is a compilation of polygons representing the California Air Pollution Control and Air Quality Management Districts, Arizona Air...

  17. AirData

    Data.gov (United States)

    U.S. Environmental Protection Agency — The AirData site provides access to yearly summaries of United States air pollution data, taken from EPA's air pollution databases. AirData has information about...

  18. California Air Basins

    Data.gov (United States)

    California Department of Resources — Air ResourcesCalifornia Air Resources BoardThe following datasets are from the California Air Resources Board: * arb_california_airbasins - California Air BasinsThe...

  19. Improved Ant Colony Optimization for Seafood Product Delivery Routing Problem

    Directory of Open Access Journals (Sweden)

    Baozhen Yao

    2014-02-01

    Full Text Available This paper deals with a real-life vehicle delivery routing problem, which is a seafood product delivery routing problem. Considering the features of the seafood product delivery routing problem, this paper formulated this problem as a multi-depot open vehicle routing problem. Since the multi-depot open vehicle routing problem is a very complex problem, a method is used to reduce the complexity of the problem by changing the multi-depot open vehicle routing problem into an open vehicle routing problem with a dummy central depot in this paper. Then, ant colony optimization is used to solve the problem. To improve the performance of the algorithm, crossover operation and some adaptive strategies are used. Finally, the computational results for the benchmark problems of the multi-depot vehicle routing problem indicate that the proposed ant colony optimization is an effective method to solve the multi-depot vehicle routing problem. Furthermore, the computation results of the seafood product delivery problem from Dalian, China also suggest that the proposed ant colony optimization is feasible to solve the seafood product delivery routing problem.

  20. 3DMRP: 3-Directional Zone-Disjoint Multipath Routing Protocol

    Science.gov (United States)

    Shin, Dongseung; Kim, Dongkyun

    In static wireless ad hoc networks such as wireless mesh networks and wireless sensor networks, multipath routing techniques are very useful for improving end-to-end delay, throughput, and load balancing, as compared to single-path routing techniques. When determining multiple paths, however, multipath routing protocols should address the well-known route coupling problem that results from a geographic proximity of adjacent routes and that hampers performance gain. Although a lot of multipath routing protocols have been proposed, most of them focused on obtaining node or link-disjoint multipaths. In order to address the route coupling problem, some multipath routing protocols utilizing zone-disjointness property were proposed. However, they suffer from an overhead of control traffic or require additional equipment such as directional antenna. This paper therefore proposes a novel multipath routing protocol, based on geographical information with low overhead, called 3-directional zone-disjoint multipath routing protocol (3DMRP). 3DMRP searches up to three zone-disjoint paths by using two techniques: 1) greedy forwarding, and 2) RREP-overhearing. One primary and two secondary paths are obtained via greedy forwarding in order to reduce control overhead, and these secondary paths are found by avoiding the RREP overhearing zone created during the primary path acquisition. In particular, two versions of 3DMRP are introduced in order to avoid the RREQ-overhearing zone. Through ns-2 simulations, 3DMRP is evaluated to verify that it achieves performance improvements in terms of throughput and control overhead.

  1. A model of ant route navigation driven by scene familiarity.

    Directory of Open Access Journals (Sweden)

    Bart Baddeley

    2012-01-01

    Full Text Available In this paper we propose a model of visually guided route navigation in ants that captures the known properties of real behaviour whilst retaining mechanistic simplicity and thus biological plausibility. For an ant, the coupling of movement and viewing direction means that a familiar view specifies a familiar direction of movement. Since the views experienced along a habitual route will be more familiar, route navigation can be re-cast as a search for familiar views. This search can be performed with a simple scanning routine, a behaviour that ants have been observed to perform. We test this proposed route navigation strategy in simulation, by learning a series of routes through visually cluttered environments consisting of objects that are only distinguishable as silhouettes against the sky. In the first instance we determine view familiarity by exhaustive comparison with the set of views experienced during training. In further experiments we train an artificial neural network to perform familiarity discrimination using the training views. Our results indicate that, not only is the approach successful, but also that the routes that are learnt show many of the characteristics of the routes of desert ants. As such, we believe the model represents the only detailed and complete model of insect route guidance to date. What is more, the model provides a general demonstration that visually guided routes can be produced with parsimonious mechanisms that do not specify when or what to learn, nor separate routes into sequences of waypoints.

  2. Multi-hop routing mechanism for reliable sensor computing.

    Science.gov (United States)

    Chen, Jiann-Liang; Ma, Yi-Wei; Lai, Chia-Ping; Hu, Chia-Cheng; Huang, Yueh-Min

    2009-01-01

    Current research on routing in wireless sensor computing concentrates on increasing the service lifetime, enabling scalability for large number of sensors and supporting fault tolerance for battery exhaustion and broken nodes. A sensor node is naturally exposed to various sources of unreliable communication channels and node failures. Sensor nodes have many failure modes, and each failure degrades the network performance. This work develops a novel mechanism, called Reliable Routing Mechanism (RRM), based on a hybrid cluster-based routing protocol to specify the best reliable routing path for sensor computing. Table-driven intra-cluster routing and on-demand inter-cluster routing are combined by changing the relationship between clusters for sensor computing. Applying a reliable routing mechanism in sensor computing can improve routing reliability, maintain low packet loss, minimize management overhead and save energy consumption. Simulation results indicate that the reliability of the proposed RRM mechanism is around 25% higher than that of the Dynamic Source Routing (DSR) and ad hoc On-demand Distance Vector routing (AODV) mechanisms.

  3. Prevention Of WormholeAttacks In Geographic Routing Protocol

    Directory of Open Access Journals (Sweden)

    E.Poornima,

    2011-01-01

    Full Text Available As mobile ad hoc network applications are deployed, security emerges as a central requirement..Position aided routing protocols can offer a significant performance increase over traditional ad hoc routing protocols. Boundary State Routing (BSR is a geographic routing protocol which routes the data using the location of the nodes. Geographic routing protocols are known to be particularly susceptible to attacks.. In this paper we present the possible attacks on BSR protocol. One of the most popular and serious attacks in ad hoc networks is wormhole attack in which two or more colluding attackers record packets at one location, and tunnel them to another location for a replay at that remote location. A wormhole attack is very powerful, and preventing the attack has proven to be very difficult. In this paper, we devise efficient methods to detect and avoid wormhole attacks in the BSR protocol. The first method namely Reverse Routing Scheme (RRS attempts to detect the intrusion action .The second technique namely Authentication of Nodes Scheme (ANS uses cryptographic concepts to detect and prevent wormhole attacks. It not only detects the fake route but also adopts preventive measures against action wormhole nodes from reappearing during routing. The proposed system is designed in Boundary state routing (BSRprotocol and analysis and simulations are performed in network simulator (NS-2.

  4. Multiple routes transmitted epidemics on multiplex networks

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Dawei [Information Security Center, State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, P.O. Box 145, Beijing 100876 (China); National Engineering Laboratory for Disaster Backup and Recovery, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Shandong Provincial Key Laboratory of Computer Network, Shandong Computer Science Center, Jinan 250014 (China); Li, Lixiang [Information Security Center, State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, P.O. Box 145, Beijing 100876 (China); National Engineering Laboratory for Disaster Backup and Recovery, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Peng, Haipeng, E-mail: penghaipeng@bupt.edu.cn [Information Security Center, State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, P.O. Box 145, Beijing 100876 (China); National Engineering Laboratory for Disaster Backup and Recovery, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Luo, Qun; Yang, Yixian [Information Security Center, State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, P.O. Box 145, Beijing 100876 (China); National Engineering Laboratory for Disaster Backup and Recovery, Beijing University of Posts and Telecommunications, Beijing 100876 (China)

    2014-02-01

    This letter investigates the multiple routes transmitted epidemic process on multiplex networks. We propose detailed theoretical analysis that allows us to accurately calculate the epidemic threshold and outbreak size. It is found that the epidemic can spread across the multiplex network even if all the network layers are well below their respective epidemic thresholds. Strong positive degree–degree correlation of nodes in multiplex network could lead to a much lower epidemic threshold and a relatively smaller outbreak size. However, the average similarity of neighbors from different layers of nodes has no obvious effect on the epidemic threshold and outbreak size. -- Highlights: •We studies multiple routes transmitted epidemic process on multiplex networks. •SIR model and bond percolation theory are used to analyze the epidemic processes. •We derive equations to accurately calculate the epidemic threshold and outbreak size. •ASN has no effect on the epidemic threshold and outbreak size. •Strong positive DDC leads to a lower epidemic threshold and a smaller outbreak size.

  5. Enhancing Transport Efficiency by Hybrid Routing Strategy

    CERN Document Server

    Dong, J -Q; Zhou, Z; Huang, L; Wu, Z -X; Do, Y; Wang, Y -H

    2012-01-01

    Traffic is essential for many dynamic processes on real networks, such as internet and urban traffic systems. The transport efficiency of the traffic system can be improved by taking full advantage of the resources in the system. In this paper, we propose a dual-strategy routing model for network traffic system, to realize the plenary utility of the whole network. The packets are delivered according to different "efficient routing strategies" [Yan, et al, Phys. Rev. E 73, 046108 (2006)]. We introduce the accumulate rate of packets, {\\eta} to measure the performance of traffic system in the congested phase, and propose the so-called equivalent generation rate of packet to analyze the jamming processes. From analytical and numerical results, we find that, for suitable selection of strategies, the dual- strategy system performs better than the single-strategy system in a broad region of strategy mixing ratio. The analytical solution to the jamming processes is verified by estimating the number of jammed nodes, w...

  6. Robustness of airline alliance route networks

    Science.gov (United States)

    Lordan, Oriol; Sallan, Jose M.; Simo, Pep; Gonzalez-Prieto, David

    2015-05-01

    The aim of this study is to analyze the robustness of the three major airline alliances' (i.e., Star Alliance, oneworld and SkyTeam) route networks. Firstly, the normalization of a multi-scale measure of vulnerability is proposed in order to perform the analysis in networks with different sizes, i.e., number of nodes. An alternative node selection criterion is also proposed in order to study robustness and vulnerability of such complex networks, based on network efficiency. And lastly, a new procedure - the inverted adaptive strategy - is presented to sort the nodes in order to anticipate network breakdown. Finally, the robustness of the three alliance networks are analyzed with (1) a normalized multi-scale measure of vulnerability, (2) an adaptive strategy based on four different criteria and (3) an inverted adaptive strategy based on the efficiency criterion. The results show that Star Alliance has the most resilient route network, followed by SkyTeam and then oneworld. It was also shown that the inverted adaptive strategy based on the efficiency criterion - inverted efficiency - shows a great success in quickly breaking networks similar to that found with betweenness criterion but with even better results.

  7. The vehicle routing problem with backhauls

    Energy Technology Data Exchange (ETDEWEB)

    Goetschalckx, M.; Jacobs-Blecha, C.

    1989-09-05

    The Vehicle Routing Problem with Backhauls is a pickup/delivery problem where on each route all deliveries must be made before any pickups. A two-phased solution methodology is proposed. In the first phase, a high quality initial feasible solution is generated based on spacefilling curves. In the second phase, this solution is improved based on optimization of the subproblems identified in a mathematical model of the problem. An extensive computational analysis of several initial solution algorithms is presented, which identifies the tradeoffs between solution quality and computational requirements. The class of greedy algorithms is capacity oriented, while K-median algorithms focus on distance. It is concluded that the greedy and K-median algorithms generate equivalent tour lengths, but that the greedy procedure reduces the required number of trucks and increases the truck utilization. The effect of exchange improvement procedures as well as optimal procedures on solution quality and run time is demonstrated. Comparisons with the Clark-Wright method adapted to backhauls are also given. 4 figs., 26 refs.

  8. Intracellular route of canine parvovirus entry.

    Science.gov (United States)

    Vihinen-Ranta, M; Kalela, A; Mäkinen, P; Kakkola, L; Marjomäki, V; Vuento, M

    1998-01-01

    The present study was designed to investigate the endocytic pathway involved in canine parvovirus (CPV) infection. Reduced temperature (18 degrees C) or the microtubule-depolymerizing drug nocodazole was found to inhibit productive infection of canine A72 cells by CPV and caused CPV to be retained in cytoplasmic vesicles as indicated by immunofluorescence microscopy. Consistent with previously published results, these data indicate that CPV enters a host cell via an endocytic route and further suggest that microtubule-dependent delivery of CPV to late endosomes is required for productive infection. Cytoplasmic microinjection of CPV particles was used to circumvent the endocytosis and membrane fusion steps in the entry process. Microinjection experiments showed that CPV particles which were injected directly into the cytoplasm, thus avoiding the endocytic pathway, were unable to initiate progeny virus production. CPV treated at pH 5.0 prior to microinjection was unable to initiate virus production, showing that factors of the endocytic route other than low pH are necessary for the initiation of infection by CPV.

  9. Cost-Appraising Techniques For Route Planning

    Science.gov (United States)

    Cheng, Pi-Yun

    1987-01-01

    Cost appraisal is one of the most important elements in route planning, especially when dynamic programming is employed in the search technique. Different missions require different routes; for example, a mission may require a minimum-length path, a terrain-constrained path, a tactical path, a threat-avoidance path, a fuel-constrained path, or a combination of such paths. An optimal path is the path whose total cost is appraised to be the minimum. One difficulty in cost appraisal is in identifying common as well as mission-specific parameters. Another difficulty is in ranking the weighting coefficients, or equivalently the importance factors. Many papers can be found on finding an optimal path for some cost function. However, there has been much less published analysis discussing the detailed definitions of cost-measuring functions other than the familiar Euclidean metrics. Known methods of cost appraisal tend to be either exclusively heuristic or numerical. In this paper we present a new formulation of cost appraisal in which intertwined employment of both approaches is evident. An application example is given.

  10. Route Scherrer closed for construction work

    CERN Multimedia

    2015-01-01

    Please note that Route Scherrer will be inaccessible for two and a half months from the beginning of March.   The part of Route Scherrer between Building 510 and Building 53 (see Figure) will be closed from the beginning of March until mid-May for civil engineering works. The superheated water pipes supplying the buildings in this area date back to 1959 and therefore present a significant risk of leakage. In order to ensure the reliable supply of superheated water, and, by extension, heating, to all premises near the Main Building (i.e. Buildings 500, 501, 503, 60, 62, 63 and 64), a new buried service duct will be installed between the basements of Buildings 53 and 61 to house a new superheated water pipe. The following car parks will, however, remain accessible for the duration of the works: the Cèdres car park, the car park for Buildings 4 and 5, and the car park situated between Buildings 32, 38 and 168.

  11. Routing of multimedia connections in hybrid networks

    Science.gov (United States)

    Koegel, John F.; Syta, Andrzej

    1993-02-01

    The prevailing vision for next generation multimedia communication systems is a digital one. However, we anticipate a transitional period in which hybrid networks involving both analog and digital technology will coexist. These analog facilities will include crossbar audio-video switches, CATV distribution systems, and dedicated lines. For some scale of use, these facilities may offer economies for connectivity to conventional analog video equipment. We are interested in connection routing that will be needed in such hybrid networks for services including video conferencing and broadcast results. The routing problem in such topologies resembles but is not identical to that found in telephone systems because of the presence of broadcast connections. We discuss representative topologies, review related work, and describe algorithms and simulation results. In addition we describe a hybrid system that we have implemented in our research lab which involves several A/V switches, CATV channels, digital video on a LAN, and a point-to-point link to an offsite conference area.

  12. Self-Healing and Optimizing Adhoc Routing

    Directory of Open Access Journals (Sweden)

    Sunil Taneja

    2012-02-01

    Full Text Available Wireless networking is an emerging field with its potential applications in extremely unpredictable and dynamic environments. Individuals and industries choose wireless because it allows flexibility of location, whether that means mobility, portability, or just ease of installation at a fixed point. Wireless networks that fix their own broken communication links may speed up their widespread acceptance. The challenge for wireless communication is optimized handling of unpredictable environment through which commu¬nications travels. Despite early problems in overcoming this pitfall, the newest develop¬ments in self-healing wireless networks are solving the problem. The changes made to the network architectures are resulting in new methods of applica¬tion design for this medium. This paper presents an overview of self healing networks and a new scheme has been proposed that tries to heal the routing when a link failure occurs. The scheme can be incorporated into any adhoc on-demand unicast routing protocol. In this research work, the proposed scheme has been incorporated to AODV and observation is that the performance has been improved. The simulations have been carried over NS2 simulator with existing schemes and proposed scheme. Simulation results indicated that the proposed technique provides robustness.

  13. Criteria as a route to the routing algorithm in mesh networks with reduced interference

    Directory of Open Access Journals (Sweden)

    V. I. Pravda

    2012-02-01

    Full Text Available The paper presents the development assessment system tracks peredichi information in the mesh network and routing algorithm that uses data evaluation. Using this algorithm reduces the interference in the network and power consumption. Provides resistance to changes in the network.

  14. Would You Follow Your Own Route Description? Cognitive Strategies in Urban Route Planning

    Science.gov (United States)

    Holscher, Christoph; Tenbrink, Thora; Wiener, Jan M.

    2011-01-01

    This paper disentangles cognitive and communicative factors influencing planning strategies in the everyday task of choosing a route to a familiar location. Describing the way for a stranger in town calls for fundamentally different cognitive processes and strategies than actually walking to a destination. In a series of experiments, this paper…

  15. "To Control Tibet, First Pacify Kham": Trade Routes and "Official Routes" (Guandao in Easternmost Kham

    Directory of Open Access Journals (Sweden)

    Patrick Booz

    2016-06-01

    Full Text Available This article focuses on the trade routes in the western Sichuan borderlands that facilitated contact and trade between Chinese counties and Eastern Tibet. In particular, the article offers a description of “official routes” (guandao—which the Chinese emperor twice proclaimed to be the vital mode of access between China and Tibet—from Chengdu, Sichuan’s provincial capital, to Khampa areas, with Lhasa as the final destination. The exchange of goods in this region followed various routes during different periods. From the tenth to sixteenth centuries, transactions occurred primarily along the borders of Amdo (Tib. A mdo, Northeastern Tibet, but for political, economic, and practical reasons, such exchanges became more limited geographically and eventually focused along the Sichuan–Kham/Ngawa border. Many routes shifted to the towns of Kangding (Tib. Dartsedo and Songpan (Tib. Zungchu, the main sites of distribution, where rich opportunities for trade and a strictly limiting transport geography made them important entrepôts that evolved into centers of prosperity. The geographic range of this article reaches to these two towns and leaves the investigation of the routes that led to western centers such as Derge, Batang, Chamdo, and Jyekundo for future research.

  16. Air Warfare

    Science.gov (United States)

    2002-03-01

    undoubtedly begat the shield; poisonous gases were countered by the mask. Surely men on the surface of the earth will not have to submit to violent air attack...properties, production methods and cost of helium are given in “Balloon and Airship Gases ,” a volume of the Ronald Aeronautic Library. 5 More complete...becomes and more inse - cure. We shall see later that even some of the men who were advancing in the path prescribed by the principle of mass

  17. Respiratory effects of air pollution on children.

    Science.gov (United States)

    Goldizen, Fiona C; Sly, Peter D; Knibbs, Luke D

    2016-01-01

    A substantial proportion of the global burden of disease is directly or indirectly attributable to exposure to air pollution. Exposures occurring during the periods of organogenesis and rapid lung growth during fetal development and early post-natal life are especially damaging. In this State of the Art review, we discuss air toxicants impacting on children's respiratory health, routes of exposure with an emphasis on unique pathways relevant to young children, methods of exposure assessment and their limitations and the adverse health consequences of exposures. Finally, we point out gaps in knowledge and research needs in this area. A greater understanding of the adverse health consequences of exposure to air pollution in early life is required to encourage policy makers to reduce such exposures and improve human health.

  18. mizuRoute version 1: a river network routing tool for a continental domain water resources applications

    Science.gov (United States)

    Mizukami, Naoki; Clark, Martyn P.; Sampson, Kevin; Nijssen, Bart; Mao, Yixin; McMillan, Hilary; Viger, Roland J.; Markstrom, Steve L.; Hay, Lauren E.; Woods, Ross; Arnold, Jeffrey R.; Brekke, Levi D.

    2016-06-01

    This paper describes the first version of a stand-alone runoff routing tool, mizuRoute. The mizuRoute tool post-processes runoff outputs from any distributed hydrologic model or land surface model to produce spatially distributed streamflow at various spatial scales from headwater basins to continental-wide river systems. The tool can utilize both traditional grid-based river network and vector-based river network data. Both types of river network include river segment lines and the associated drainage basin polygons, but the vector-based river network can represent finer-scale river lines than the grid-based network. Streamflow estimates at any desired location in the river network can be easily extracted from the output of mizuRoute. The routing process is simulated as two separate steps. First, hillslope routing is performed with a gamma-distribution-based unit-hydrograph to transport runoff from a hillslope to a catchment outlet. The second step is river channel routing, which is performed with one of two routing scheme options: (1) a kinematic wave tracking (KWT) routing procedure; and (2) an impulse response function - unit-hydrograph (IRF-UH) routing procedure. The mizuRoute tool also includes scripts (python, NetCDF operators) to pre-process spatial river network data. This paper demonstrates mizuRoute's capabilities to produce spatially distributed streamflow simulations based on river networks from the United States Geological Survey (USGS) Geospatial Fabric (GF) data set in which over 54 000 river segments and their contributing areas are mapped across the contiguous United States (CONUS). A brief analysis of model parameter sensitivity is also provided. The mizuRoute tool can assist model-based water resources assessments including studies of the impacts of climate change on streamflow.

  19. Parallel routing in Mobile Ad-Hoc Networks

    CERN Document Server

    Day, Khaled; Arafeh, Bassel; Alzeidi, Nasser; 10.5121/ijcnc.2011.3506

    2011-01-01

    This paper proposes and evaluates a new position-based Parallel Routing Protocol (PRP) for simultaneously routing multiple data packets over disjoint paths in a mobile ad-hoc network (MANET) for higher reliability and reduced communication delays. PRP views the geographical region where the MANET is located as a virtual 2-dimensional grid of cells. Cell-disjoint (parallel) paths between grid cells are constructed and used for building pre-computed routing tables. A single gateway node in each grid cell handles routing through that grid cell reducing routing overheads. Each node maintains updated information about its own location in the virtual grid using GPS. Nodes also keep track of the location of other nodes using a new proposed cell-based broadcasting algorithm. Nodes exchange energy level information with neighbors allowing energy-aware selection of the gateway nodes. Performance evaluation results have been derived showing the attractiveness of the proposed parallel routing protocol from different resp...

  20. Pheromone-Based Ant Routing System for IP Networks

    Institute of Scientific and Technical Information of China (English)

    张林; 任勇; 山秀明

    2004-01-01

    The pheromone-based ant routing algorithm is a distributed routing algorithm with good scalability and robustness. A 2-D cellular automata (CA) model of the computer network was presented to analyze the algorithm. The results show that the procedure of establishing a stable route is self-organized towards the attractive peculiar state, and the duration of time for the routing establishment is power-law distributed. A practical ant routing protocol over an IP network was also presented, and two simulations were done to compare the performance dynamic and the load balancing performance between this protocol and the open shortest path first (OSPF) protocol. The results show that the ant routing protocol out-performs OSPF in these aspects.

  1. Analysis on Ad Hoc Routing Protocols in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    P.N.Renjith

    2012-12-01

    Full Text Available Outlook of wireless communication system marked an extreme transform with the invention of Wireless Sensor Networks (WSN. WSN is a promising technolog y for enabling a variety of applications like environmental monitoring, security and applications that save our lives and assets. In WSN, large numbers of sensor nodes are deployed to sensing and gathering information and forward them to the base station with the help of routing protocol. Routing protocols plays a major role by identifying and maintaining the routes in the network. Competence o f sensor networks relay on the strong and effective routing protocol used. In this paper, we present a simulation based performance evaluation of differen t Ad hoc routing protocols like AODV, DYMO, FSR, LANM AR, RIP and ZRP in Wireless Sensor Networks. Based on the study, the future research areas and k ey challenges for routing protocol in WSN are to optimize network performance for QoS support and en ergy conservation

  2. Memoryless Routing in Convex Subdivisions: Random Walks are Optimal

    CERN Document Server

    Chen, Dan; Dujmovic, Vida; Morin, Pat

    2009-01-01

    A memoryless routing algorithm is one in which the decision about the next edge on the route to a vertex t for a packet currently located at vertex v is made based only on the coordinates of v, t, and the neighbourhood, N(v), of v. The current paper explores the limitations of such algorithms by showing that, for any (randomized) memoryless routing algorithm A, there exists a convex subdivision on which A takes Omega(n^2) expected time to route a message between some pair of vertices. Since this lower bound is matched by a random walk, this result implies that the geometric information available in convex subdivisions is not helpful for this class of routing algorithms. The current paper also shows the existence of triangulations for which the Random-Compass algorithm proposed by Bose etal (2002,2004) requires 2^{\\Omega(n)} time to route between some pair of vertices.

  3. COSR: A Reputation-Based Secure Route Protocol in MANET

    Directory of Open Access Journals (Sweden)

    Yang LaurenceT

    2010-01-01

    Full Text Available Now, the route protocols defined in the Mobile Ad Hoc Network (MANET are constructed in a common assumption which all nodes contained in such networks are trustworthy and cooperative. Once malicious or selfish nodes exist, all route paths built by these protocols must be broken immediately. According to the secure problems within MANET, this paper proposes Cooperative On-demand Secure Route (COSR, a novel secure source route protocol, against malicious and selfish behaviors. COSR measures node reputation (NR and route reputation (RR by contribution, Capability of Forwarding (CoF and recommendation upon Dynamic Source Route (DSR and uses RR to balance load to avoid hotpoint. Furthermore, COSR defines path collection algorithm by NR to enhance efficiency of protocol. At last, we verify COSR through GloMoSim. Results show that COSR is secure and stable.

  4. Route Challenging Scheme Using Friend Based Rating in MANETs

    Directory of Open Access Journals (Sweden)

    S. Shantha Meena

    2013-04-01

    Full Text Available Security and Route identification are the major challenges in MANETs. Existing neighbour based routing algorithms provide route based on the quantity of data transferred [1] which may result in congestion. This is because the route having higher amount of transaction is preferred every time. In this paper we propose a Friend Based Routing algorithm [FBRA] for solving this problem. Here, the appropriate route is found not only based on the quantity of data transferred but also considers RSS and RTT. For providing re-authentication to the nodes in the network, FBRA uses Zero-Knowledge Protocol. The main advantage of this method is providing enhanced security and distinguishes the malicious nodes from the trusted nodes in the network.

  5. Routing in Highly Dynamic Ad Hoc Networks: Issues and Challenges

    Directory of Open Access Journals (Sweden)

    Varun G Menon

    2016-04-01

    Full Text Available The aim of this research paper is to analyze the various issues and challenges involved in routing of data packets in highly mobile ad hoc networks. Routing in ad hoc networks has always been a challenging and tough task due to the dynamic topology and error prone wireless channel. There are a number of issues like lack of centralized control, constantly moving nodes etc that has to be considered while routing a data packet from the source to the destination in the ad hoc network. Routing of data packets becomes much more difficult with increased mobility of nodes. This paper analyses the various issues in routing of data packets from the source to the destination node and also lists down the parameters that has to be considered while designing and selecting a routing protocol for highly mobile ad hoc networks.

  6. Tramp Ship Routing and Scheduling - Incorporating Additional Complexities

    DEFF Research Database (Denmark)

    Vilhelmsen, Charlotte

    for tramp ship routing and scheduling problems. This is done in the context of Operations Research, a research field that has achieved great success within optimisation-based planning for vehicle routing problems and in many other areas. The first part of this thesis contains a comprehensive introduction...... of their demand in advance. However, the detailed requirements of these contract cargoes can be subject to ongoing changes, e.g. the destination port can be altered. For tramp operators, a main concern is therefore the efficient and continuous planning of routes and schedules for the individual ships. Due...... to tramp ship routing and scheduling. This includes modelling approaches, solution methods as well as an analysis of the current status and future direction of research within tramp ship routing and scheduling. We argue that rather than developing new solution methods for the basic routing and scheduling...

  7. A Secure Multi-Routing Platform for Ad Hoc Network

    Institute of Scientific and Technical Information of China (English)

    LU She-jie; CHEN Jing; XIONG Zai-hong

    2008-01-01

    In an ad hoc network, it is usually difficult to optimize the assignment of network routing resources using a single type of routing protocol due to the differences in network scale, node moving mode and node distribution. Therefore, it is desirable to have nodes run multiple routing protocols simultaneously so that more than one protocols can be chosen to work jointly. For this purpose,a multiple routing platform for Ad hoc networks is proposed on a higher level of current routing protocols. In order to ensure the security of the platform, a security mechanism and its formal analysis by BAN logic is given. The simulation results of the network performance demonstrate that the proposed multi-routing platform is practicable in some complex applications.

  8. Gossip Based Routing Protocol Design for Ad Hoc Networks

    OpenAIRE

    Toqeer Mahmood; Tabbassam Nawaz; Rehan Ashraf; Syed M. Adnan Shah

    2012-01-01

    A spontaneously mannered decentralized network with no formal infrastructure and limited in temporal and spatial extent where each node communicate with each other over a wireless channel and is willing to forward data for other nodes is called as Wireless Ad Hoc network. In this research study, we proposed a routing strategy based on gossip based routing approach that follows the proactive routing with some treatment for wireless Ad Hoc network. The analytical verification of our proposed id...

  9. Dynamic Vehicle Routing for Robotic Networks (Workshop Briefing Charts)

    Science.gov (United States)

    2010-06-29

    theoretic interpretation FB, EF, MP, KS, SLS (UCSB, MIT) Dynamic Vehicle Routing (Lecture 5/8) 29jun10 @ Baltimore, ACC 25 / 44 Partitioning with gossip ... Routing (Lecture 5/8) 29jun10 @ Baltimore, ACC 26 / 44 Gossip (asynchronous pair-wise) partitioning policy 1 Random communication between two regions 2...Dynamic Vehicle Routing for Robotic Networks Lecture #1: Introduction Francesco Bullo1 Emilio Frazzoli2 Marco Pavone2 Ketan Savla2 Stephen L. Smith2

  10. LBR: Load Balancing Routing Algorithm for Wireless Sensor Networks

    Science.gov (United States)

    Daabaj, Khaled; Dixon, Mike; Koziniec, Terry

    2010-06-01

    Homogeneous wireless sensor networks (WSNs) are organized using identical sensor nodes, but the nature of WSNs operations results in an imbalanced workload on gateway sensor nodes which may lead to a hot-spot or routing hole problem. The routing hole problem can be considered as a natural result of the tree-based routing schemes that are widely used in WSNs, where all nodes construct a multi-hop routing tree to a centralized root, e.g., a gateway or base station. For example, sensor nodes on the routing path and closer to the base station deplete their own energy faster than other nodes, or sensor nodes with the best link state to the base station are overloaded with traffic from the rest of the network and experience a faster energy depletion rate than their peers. Routing protocols for WSNs are reliability-oriented and their use of reliability metric to avoid unreliable links makes the routing scheme worse. However, none of these reliability oriented routing protocols explicitly uses load balancing in their routing schemes. Since improving network lifetime is a fundamental challenge of WSNs, we present, in this chapter, a novel, energy-wise, load balancing routing (LBR) algorithm that addresses load balancing in an energy efficient manner by maintaining a reliable set of parent nodes. This allows sensor nodes to quickly find a new parent upon parent loss due to the existing of node failure or energy hole. The proposed routing algorithm is tested using simulations and the results demonstrate that it outperforms the MultiHopLQI reliability based routing algorithm.

  11. Performance Evaluation of the WSN Routing Protocols Scalability

    OpenAIRE

    2008-01-01

    Scalability is an important factor in designing an efficient routing protocol for wireless sensor networks (WSNs). A good routing protocol has to be scalable and adaptive to the changes in the network topology. Thus scalable protocol should perform well as the network grows larger or as the workload increases. In this paper, routing protocols for wireless sensor networks are simulated and their performances are evaluated to determine their capability for supporting network ...

  12. Performance Evaluation of the WSN Routing Protocols Scalability

    Directory of Open Access Journals (Sweden)

    L. Alazzawi

    2008-01-01

    Full Text Available Scalability is an important factor in designing an efficient routing protocol for wireless sensor networks (WSNs. A good routing protocol has to be scalable and adaptive to the changes in the network topology. Thus scalable protocol should perform well as the network grows larger or as the workload increases. In this paper, routing protocols for wireless sensor networks are simulated and their performances are evaluated to determine their capability for supporting network scalability.

  13. BALANCE ROUTING TRAFFIC IN GENERALIZED SHUFFLE-EXCHANGE NETWORK

    Institute of Scientific and Technical Information of China (English)

    Chen Zhen; Liu Zengji; Qiu Zhiliang; Chen Peng; Tao Xiaoming

    2005-01-01

    A methodology is proposed to handle problem that under equiproble address of packet traffic at the input port, Generalized Shuffle-Exchange Network (GSEN) routes traffic unevenly because of the unbalanced routing tags. The idea is to use routing tag according to probability, which can be evaluated by using Moore-Penrose inverse in matrix analysis. An instance is used to illustrate the idea, and the simulation is done to show the improvement in performance issues.

  14. Context Aware Routing Management Architecture for Airborne Networks

    Science.gov (United States)

    2012-03-22

    Distance Vector Protocol The Ad Hoc On-Demand Distance Vector Protocol ( AODV ) is a MANET protocol with quick convergence that creates routes on demand...that are loop free. AODV requires very low processing and memory overhead when compared to other MANET routing protocols while delivering excellent...Figure 2.2: Ad Hoc On-Demand Distance Vector Protocol – Node A requests routing information for node G. The AODV algorithm does not require bootstrapping

  15. Perancangan dan Analisis Redistribution Routing Protocol OSPF dan EIGRP

    Directory of Open Access Journals (Sweden)

    DWI ARYANTA

    2016-02-01

    Full Text Available Abstrak OSPF (Open Shortest Path First dan EIGRP (Enhanced Interior Gateway Routing Protocol adalah dua routing protokol yang banyak digunakan dalam jaringan komputer. Perbedaan karakteristik antar routing protokol menimbulkan masalah dalam pengiriman paket data. Teknik redistribution adalah solusi untuk melakukan komunikasi antar routing protokol. Dengan menggunakan software Cisco Packet Tracer 5.3 pada penelitian ini dibuat simulasi OSPF dan EIGRP yang dihubungkan oleh teknik redistribution, kemudian dibandingkan kualitasnya dengan single routing protokol EIGRP dan OSPF. Parameter pengujian dalam penelitian ini adalah nilai time delay dan trace route. Nilai trace route berdasarkan perhitungan langsung cost dan metric dibandingkan dengan hasil simulasi. Hasilnya dapat dilakukan proses redistribution OSPF dan EIGRP. Nilai delay redistribution lebih baik 1% dibanding OSPF dan 2-3% di bawah EIGRP tergantung kepadatan traffic. Dalam perhitungan trace route redistribution dilakukan 2 perhitungan, yaitu cost untuk area OSPF dan metric pada area EIGRP. Pengambilan jalur utama dan alternatif pengiriman paket berdasarkan nilai cost dan metric yang terkecil, hal ini terbukti berdasarkan perhitungan dan simulasi. Kata kunci: OSPF, EIGRP, Redistribution, Delay, Cost, Metric. Abstract OSPF (Open Shortest Path First and EIGRP (Enhanced Interior Gateway Routing Protocol are two routing protocols are widely used in computer networks. Differences between the characteristics of routing protocols pose a problem in the delivery of data packets. Redistribution technique is the solution for communication between routing protocols. By using the software Cisco Packet Tracer 5.3 in this study were made simulating OSPF and EIGRP redistribution linked by technique, then compared its quality with a single EIGRP and OSPF routing protocols. Testing parameters in this study is the value of the time delay and trace route. Value trace route based on direct calculation of cost

  16. Influence of queue propagation and dissipation on route travel times

    DEFF Research Database (Denmark)

    Raovic, Nevena

    and dissipation through the CTM, LTM and DQM are studied. A simple network allows to show how these approaches influence route travel time. Furthermore, the possibility of changing the existing DQM is considered in order to more realistically represent queue propagation and dissipation, which would lead to more...... into account (Bliemer, 2008). Yperman (2007) indicates that there is a significant difference in queue-propagation and queue-dissipation between the LTM and DQM. This results in different route travel times, and can further affect route choice. In this paper, different approaches to represent queue propagation...... accurate route travel times....

  17. A New Approach to VC Routing in ATM Networks

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A new ant-algorithm-based routing approach is proposed for the VC routing problem with considering the comprehensive effect between the resource utilization and the load balance in ATM networks. In the approach, the backup paths are calculated first, and then an ant algorithm based on the ability of ants to find the shortest path between their nest and the food source during their searching food, is constructed to optimize the VC global route.Simulation results show that the proposed approach can realize VC routing effectively according to the current traffic states in the networks and the user-specified delay requirements.

  18. Gossip Based Routing Protocol Design for Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Toqeer Mahmood

    2012-01-01

    Full Text Available A spontaneously mannered decentralized network with no formal infrastructure and limited in temporal and spatial extent where each node communicate with each other over a wireless channel and is willing to forward data for other nodes is called as Wireless Ad Hoc network. In this research study, we proposed a routing strategy based on gossip based routing approach that follows the proactive routing with some treatment for wireless Ad Hoc network. The analytical verification of our proposed idea shows that it is a better approach based on gossip routing.

  19. Evaluating Wireless Proactive Routing Protocols under Scalability and Traffic Constraints

    CERN Document Server

    Javaid, N; Khan, Z A; Khan, U; Djouani, K

    2012-01-01

    In this paper, we evaluate and analyze the impact of different network loads and varying no. of nodes on distance vector and link state routing algorithms. We select three well known proactive protocols; Destination Sequenced Distance Vector (DSDV) operates on distance vector routing, while Fisheye State Routing (FSR) and Optimized Link State Routing (OLSR) protocols are based on link state routing. Further, we evaluate and compare the effects on the performance of protocols by changing the routing strategies of routing algorithms. We also enhance selected protocols to achieve high performance. We take throughput, End-to-End Delay (E2ED) and Normalized Routing Load (NRL) as performance metrics for evaluation and comparison of chosen protocols both with default and enhanced versions. Based upon extensive simulations in NS-2, we compare and discuss performance trade-offs of the protocols, i.e., how a protocol achieves high packet delivery by paying some cost in the form of increased E2ED and/or routing overhead...

  20. Characterization of Static/Dynamic Topological Routing For Grid Networks

    DEFF Research Database (Denmark)

    Gutierrez Lopez, Jose Manuel; Cuevas, Ruben; Riaz, M. Tahir;

    2009-01-01

    Grid or 2D Mesh structures are becoming one of the most attractive network topologies to study. They can be used in many different fields raging from future broadband networks to multiprocessors structures. In addition, the high requirements of future services and applications demand more flexible...... and adaptive networks. Topological routing in grid networks is a simple and efficient alternative to traditional routing techniques, e.g. routing tables, and the paper extends this kind of routing providing a "Dynamic" attribute. This new property attempts to improve the overall network performance for future...

  1. Trust-Based Route Selection in Dynamic Source Routin

    DEFF Research Database (Denmark)

    Jensen, Christian D.; Connell, Paul O

    2006-01-01

    Unlike traditional mobile wireless networks, ad hoc networks do not rely on any fixed infrastructure. Nodes rely on each other to route packets to other mobile nodes or toward stationary nodes that may act as a gateway to a fixed network. Mobile nodes are generally assumed to participate as routers......, which selects the route based on a local evaluation of the trustworthiness of all known intermediary nodes (routers) on the route to the destination. We have implemented this mechanism in an existing ad hoc routing protocol, and we show how trust can be built from previous experience and how trust can...

  2. DNA display I. Sequence-encoded routing of DNA populations.

    Directory of Open Access Journals (Sweden)

    David R Halpin

    2004-07-01

    Full Text Available Recently reported technologies for DNA-directed organic synthesis and for DNA computing rely on routing DNA populations through complex networks. The reduction of these ideas to practice has been limited by a lack of practical experimental tools. Here we describe a modular design for DNA routing genes, and routing machinery made from oligonucleotides and commercially available chromatography resins. The routing machinery partitions nanomole quantities of DNA into physically distinct subpools based on sequence. Partitioning steps can be iterated indefinitely, with worst-case yields of 85% per step. These techniques facilitate DNA-programmed chemical synthesis, and thus enable a materials biology that could revolutionize drug discovery.

  3. Energy Aware Simple Ant Routing Algorithm for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Sohail Jabbar

    2015-01-01

    Full Text Available Network lifetime is one of the most prominent barriers in deploying wireless sensor networks for large-scale applications because these networks employ sensors with nonrenewable scarce energy resources. Sensor nodes dissipate most of their energy in complex routing mechanisms. To cope with limited energy problem, we present EASARA, an energy aware simple ant routing algorithm based on ant colony optimization. Unlike most algorithms, EASARA strives to avoid low energy routes and optimizes the routing process through selection of least hop count path with more energy. It consists of three phases, that is, route discovery, forwarding node, and route selection. We have improved the route discovery procedure and mainly concentrate on energy efficient forwarding node and route selection, so that the network lifetime can be prolonged. The four possible cases of forwarding node and route selection are presented. The performance of EASARA is validated through simulation. Simulation results demonstrate the performance supremacy of EASARA over contemporary scheme in terms of various metrics.

  4. Network parameters awareness for routing discovery in autonomic optical Internet

    Institute of Scientific and Technical Information of China (English)

    JIN Jin; WANG Hong-xiang; JI Yue-feng

    2009-01-01

    The article proposes a network parameter-awareness (NPA) method and applies it to routing discovery algorithms in autonomic optical Internet. This NPA method can perceive the main parameters of the network, such as delay, jitter and traffic, which can represent the current situation of the network. And these parameters enable network to determine the appropriate nodes for routing discovery. The simulation results of evaluating performance of a network with NPA method and its routing applications show that the method and its applications in routing improve the performance of the network significantly with quality of service (QoS) guaranteed.

  5. CORMEN: Coding-Aware Opportunistic Routing in Wireless Mess Network

    CERN Document Server

    Islam, Jeherul

    2010-01-01

    These Network Coding improves the network operation beyond the traditional routing or store-and-forward, by mixing of data stream within a network. Network coding techniques explicitly minimizes the total no of transmission in wireless network. The Coding-aware routing maximizes the coding opportunity by finding the coding possible path for every packet in the network. Here we propose CORMEN: a new coding-aware routing mechanism based on opportunistic routing. In CORMEN, every node independently can take the decision whether to code packets or not and forwarding of packets is based on the coding opportunity available.

  6. A double candidate survivable routing protocol for HAP network

    Science.gov (United States)

    He, Panfeng; Li, Chunyue; Ni, Shuyan

    2016-11-01

    To improve HAP network invulnerability, and at the same time considering the quasi-dynamic topology in HAP network, a simple and reliable routing protocol is proposed in the paper. The protocol firstly uses a double-candidate strategy for the next-node select to provide better robustness. Then during the maintenance stage, short hello packets instead of long routing packets are used only to check link connectivity in the quasi-dynamic HAP network. The route maintenance scheme based on short hello packets can greatly reduce link spending. Simulation results based on OPNET demonstrate the effectiveness of the proposed routing protocol.

  7. A Performance Comparison of Routing Protocols for Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Hicham Zougagh

    2014-09-01

    Full Text Available Mobile Ad hoc Network (MANET is a collection of mobile nodes in which the wireless links are frequently broken down due to mobility and dynamic infrastructure. Routing is a significant issue and challenge in ad hoc networks. Many routing protocols have been proposed like OLSR, AODV so far to improve the routing performance and reliability. In this paper, we describe the Optimized Link State Routing Protocol (OLSR and the Ad hoc On-Demand Distance Vector (AODV. We evaluate their performance through exhaustive simulations using the Network Simulator 2 (ns2 by varying conditions (node mobility, network density.

  8. Efficient Load Balancing Routing Technique for Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Mahdi Abdulkader Salem

    2016-05-01

    Full Text Available The mobile ad hoc network (MANET is nothing but the wireless connection of mobile nodes which provides the communication and mobility among wireless nodes without the need of any physical infrastructure or centralized devices such as access point or base station. The communication in MANET is done by routing protocols. There are different categories of routing protocols introduced with different goals and objectives for MANETs such as proactive routing protocols (e.g. DSDV, reactive routing protocols (e.g. ADOV, geographic routing protocols (e.g. GRP, hybrid routing protocols etc. There are two important research problems with such routing protocols to address such as efficient load balancing and energy efficiency. In this paper, we are focusing on evaluation and analysis of efficient load balancing protocol design for MANET. Inefficient load balancing technique results in increasing routing overhead, poor packet delivery ratio, and other Quality of Service (QoS parameters. In literature, there are a number of different methods proposed for improving the performance of routing protocols by efficient load balancing among mobile nodes communication. However, most of the methods suffer from various limitations. In this paper, we propose a novel technique for improved the QoS performance of load balancing approach as well as increasing the network lifetime. Evaluation of Network lifetime is out of scope of this paper.

  9. Traffic modifications on Routes Rutherford, Democrite and Fermi

    CERN Multimedia

    2015-01-01

    The GS Department would like to inform you that, until the end of December, the construction of Building 245 will result in the following traffic modifications: Traffic on Route Rutherford will be partially restricted in front of the construction site, Traffic on Route Democrite will be one-way towards Route Rutherford. Also, please note that due to construction work in front of Building 377, Route Fermi will be closed from Wednesday, 10 June until Friday, 7 August. Thank you for your understanding.

  10. Safe Trust Alert Routing in MANET

    Directory of Open Access Journals (Sweden)

    Srikanth Meda

    2015-10-01

    Full Text Available  The main characteristic of the ad-hoc network is dynamic topology. In this, nodes modifications its position usually and these nodes have to be compelled to be compelled to adapt for the topology amendment. Nodes can amendment position quite frequently that mean the standard of the network. For quick info transmission, we'd sort of a routing protocol that adapts to topology changes. For our convenience, we've projected a fast and secure protocol that's proactive and reactive in nature. Proactive nature used for adding the node into list, as a results of it taking a short while to line the selection relating to node. And reactive nature used for locating the path for providing fast transmission.

  11. Dynamic Routing of Short Transfer Baggage

    DEFF Research Database (Denmark)

    Clausen, Tommy; Pisinger, David

    of dispatch. Computational results are presented for real-life passenger data with stochastic bag arrival times and travel times. The results indicate that the algorithm is able to dispatch the baggage considerably better than the manual delivery plans reported in the case study, and due to its fast running...... times, the algorithm is suitable for dynamic dispatching. Investigations on the impact of uncertainty and fleet size make it possible to support a trade-off between fleet size and expected service level.......We consider a variant of the Vehicle Routing Problem that arises in airports when transporting baggage for passengers with connecting flights. Each bag can be delivered in two locations with disjunctive time windows. The task is to define multiple trips for the vehicles in order to deliver bags...

  12. Plasmonic Route to Reconfigurable Polarization Optics

    CERN Document Server

    Li, L; Tang, X M; Wang, S M; Wang, Q J; Zhu, S N

    2014-01-01

    Surface plasmon polariton (SPP) as a bounded mode on a metal/dielectric interface intrinsically has a definite transverse magnetic (TM) polarization that usually lacks further manipulations. However, the in-plane longitudinal components of SPP field can produce versatile polarization states when two orthogonal propagating SPP interfere with each other. Here, we demonstrated a plasmonic polarization router by designing appropriate nanohole arrays that can selectively scatter the interfered SPP fields to desired light beams. It is well proved that our device is able to reconfigure a certain input polarization to all kinds of states with respect to a scattered light. Accompanied with a composite phase modulation by diffractions, multiple focusing beams with different polarization states are simultaneously achieved, promising the possibility in polarization multiplexing and related signal processing. Our design offers a new route for achieving full control of the optical polarizations as well as the optical spin-...

  13. Routing Physarum with electrical flow/current

    CERN Document Server

    Tsuda, Soichiro; Adamatzky, Andrew; Mills, Jonathan

    2012-01-01

    Plasmodium stage of Physarum polycephalum behaves as a distributed dynamical pattern formation mechanism who's foraging and migration is influenced by local stimuli from a wide range of attractants and repellents. Complex protoplasmic tube network structures are formed as a result, which serve as efficient `circuits' by which nutrients are distributed to all parts of the organism. We investigate whether this `bottom-up' circuit routing method may be harnessed in a controllable manner as a possible alternative to conventional template-based circuit design. We interfaced the plasmodium of Physarum polycephalum to the planar surface of the spatially represented computing device, (Mills' Extended Analog Computer, or EAC), implemented as a sheet of analog computing material whose behaviour is input and read by a regular 5x5 array of electrodes. We presented a pattern of current distribution to the array and found that we were able to select the directional migration of the plasmodium growth front by exploiting pla...

  14. Genetic Algorithms for multiple objective vehicle routing

    CERN Document Server

    Geiger, Martin Josef

    2008-01-01

    The talk describes a general approach of a genetic algorithm for multiple objective optimization problems. A particular dominance relation between the individuals of the population is used to define a fitness operator, enabling the genetic algorithm to adress even problems with efficient, but convex-dominated alternatives. The algorithm is implemented in a multilingual computer program, solving vehicle routing problems with time windows under multiple objectives. The graphical user interface of the program shows the progress of the genetic algorithm and the main parameters of the approach can be easily modified. In addition to that, the program provides powerful decision support to the decision maker. The software has proved it's excellence at the finals of the European Academic Software Award EASA, held at the Keble college/ University of Oxford/ Great Britain.

  15. Traffic routes and signals for the tonoplast.

    Science.gov (United States)

    Pedrazzini, Emanuela; Komarova, Nataliya Y; Rentsch, Doris; Vitale, Alessandro

    2013-06-01

    Tonoplast, the membrane delimiting plant vacuoles, regulates ion, water and nutrient movement between the cytosol and the vacuolar lumen through the activity of its membrane proteins. Correct traffic of proteins from the endoplasmic reticulum (ER) to the tonoplast requires (i) approval by the ER quality control, (ii) motifs for exit from the ER and (iii) motifs that promote sorting to the tonoplast. Recent evidence suggests that this traffic follows different pathways that are protein-specific and could also reflect vacuole specialization for lytic or storage function. The routes can be distinguished based on their sensitivity to drugs such as brefeldin A and C834 as well as using mutant plants that are defective in adaptor proteins of vesicle coats, or dominant-negative mutants of Rab GTPases.

  16. A new route to process diamond wires

    Directory of Open Access Journals (Sweden)

    Marcello Filgueira

    2003-06-01

    Full Text Available We propose an original route to process diamond wires, denominated In Situ Technology, whose fabrication involves mechanical conformation processes, such as rotary forging, copper tubes restacking, and thermal treatments, such as sintering and recrystallisation of a bronze 4 wt.% diamond composite. Tensile tests were performed, reaching an ultimate tensile strength (UTS of 230 MPa for the diameter of Æ = 1.84 mm. Scanning electron microscopy showed the diamond crystals distribution along the composite rope during its manufacture, as well as the diamond adhesion to the bronze matrix. Cutting tests were carried out with the processed wire, showing a probable performance 4 times higher than the diamond sawing discs, however its probable performance was about 5 to 8 times less than the conventional diamond wires (pearl system due to the low abrasion resistance of the bronze matrix, and low adhesion between the pair bronze-diamond due to the use of not metallised diamond single crystals.

  17. Adaptive Probabilistic Flooding for Multipath Routing

    CERN Document Server

    Betoule, Christophe; Clavier, Remi; Rossi, Dario; Rossini, Giuseppe; Thouenon, Gilles

    2011-01-01

    In this work, we develop a distributed source routing algorithm for topology discovery suitable for ISP transport networks, that is however inspired by opportunistic algorithms used in ad hoc wireless networks. We propose a plug-and-play control plane, able to find multiple paths toward the same destination, and introduce a novel algorithm, called adaptive probabilistic flooding, to achieve this goal. By keeping a small amount of state in routers taking part in the discovery process, our technique significantly limits the amount of control messages exchanged with flooding -- and, at the same time, it only minimally affects the quality of the discovered multiple path with respect to the optimal solution. Simple analytical bounds, confirmed by results gathered with extensive simulation on four realistic topologies, show our approach to be of high practical interest.

  18. Soft chemical routes to semiconductor nanostructures

    Indian Academy of Sciences (India)

    Ujjal K Gautam; Kripsindhu Sardar; F L Deepak; C N R Rao

    2005-10-01

    Soft chemistry has emerged as an important means of generating nanocrystals, nanowires and other nanostructures of semiconducting materials. We describe the synthesis of CdS and other metal chalcogenide nanocrystals by a solvothermal route. We also describe the synthesis of nanocrystals of AlN, GaN and InN by the reaction of hexamethyldisilazane with the corresponding metal chloride or metal cupferronate under solvothermal conditions. Nanowires of Se and Te have been obtained by a self-seeding solution-based method. A single source precursor based on urea complexes of metal chlorides gives rise to metal nitride nanocrystals, nanowires and nanotubes. The liquid-liquid interface provides an excellent medium for preparing single-crystalline films of metal chalcogenides.

  19. Hybrid Trust Model for Internet Routing

    CERN Document Server

    Rantala, Pekka; Isoaho, Jouni

    2011-01-01

    The current Internet is based on a fundamental assumption of reliability and good intent among actors in the network. Unfortunately, unreliable and malicious behaviour is becoming a major obstacle for Internet communication. In order to improve the trustworthiness and reliability of the network infrastructure, we propose a novel trust model to be incorporated into BGP routing. In our approach, trust model is defined by combining voting and recommendation to direct trust estimation for neighbour routers located in different autonomous systems. We illustrate the impact of our approach with cases that demonstrate the indication of distrusted paths beyond the nearest neighbours and the detection of a distrusted neighbour advertising a trusted path. We simulated the impact of weighting voted and direct trust in a rectangular grid of 15*15 nodes (autonomous systems) with a randomly connected topology.

  20. Full truckload vehicle routing problem with profits

    Directory of Open Access Journals (Sweden)

    Jian Li

    2014-04-01

    Full Text Available A new variant of the full truckload vehicle routing problem is studied. In this problem there are more than one delivery points corresponding to the same pickup point, and one order is allowed to be served several times by the same vehicle or different vehicles. For the orders which cannot be assigned because of resource constraint, the logistics company outsources them to other logistics companies at a certain cost. To maximize its profits, logistics company decides which to be transported by private fleet and which to be outsourced. The mathematical model is constructed for the problem. Since the problem is NP-hard and it is difficult to solve the large-scale problems with an exact algorithm, a hybrid genetic algorithm is proposed. Computational results show the effectiveness of the hybrid genetic algorithm.

  1. Integrated Job Scheduling and Network Routing

    DEFF Research Database (Denmark)

    Gamst, Mette; Pisinger, David

    2013-01-01

    We consider an integrated job scheduling and network routing problem which appears in Grid Computing and production planning. The problem is to schedule a number of jobs at a finite set of machines, such that the overall profit of the executed jobs is maximized. Each job demands a number...... of resources which must be sent to the executing machine through a network with limited capacity. A job cannot start before all of its resources have arrived at the machine. The scheduling problem is formulated as a Mixed Integer Program (MIP) and proved to be NP-hard. An exact solution approach using Dantzig...... instances with 1,000 jobs and 1,000 machines covering 24 hours of scheduling activity on a Grid network. The algorithm is also compared to simulations of a real-life Grid, and results show that the solution quality significantly increases when solving the problem to optimality. The promising results...

  2. HYBRID TRUST MODEL FOR INTERNET ROUTING

    Directory of Open Access Journals (Sweden)

    Pekka Rantala

    2011-05-01

    Full Text Available The current Internet is based on a fundamental assumption of reliability and good intent among actors inthe network. Unfortunately, unreliable and malicious behaviour is becoming a major obstacle forInternet communication. In order to improve the trustworthiness and reliability of the networkinfrastructure, we propose a novel trust model to be incorporated into BGP routing. In our approach,trust model is defined by combining voting and recommendation to direct trust estimation for neighbourrouters located in different autonomous systems. We illustrate the impact of our approach with cases thatdemonstrate the indication of distrusted paths beyond the nearest neighbours and the detection of adistrusted neighbour advertising a trusted path. We simulated the impact of weighting voted and directtrust in a rectangular grid of 15*15 nodes (autonomous systems with a randomly connected topology.

  3. ROUTE PLAN DESIGNER FOR TRACTOR GUIDANCE SYSTEMS

    DEFF Research Database (Denmark)

    Sveistrup, Daniel; Jørgensen, Rasmus Nyholm; Green, Ole

    2010-01-01

    thedevelopment and deployment of georeferenced routes to be used for full scale field trial designsassisted by auto-steering solutions, including the steps needed to lay out the full scale multitreatmentsetups, georeference these setups via Google Earth and transfer them to an auto-guidancetractor computer....... The software works in conjunction with Google Earth to import field boundaries,and for viewing, validating and georeferencing completed field trial designs. The software isplatform independent and online distributed by means of the Java development environment.Two case studies were applied for demonstrating...... was outlined, it took less thanone hour entering the design into the software and generating the auto-guidance files.KeywordsGIS, Auto steering systems, plot trial design, full-scale field trials, Java...

  4. Two Alternative Routes to MS2 Nanotubes

    Institute of Scientific and Technical Information of China (English)

    Yanqing LIU; Changsheng LI; Jinghai YANG; Zhong HUA; Junmao LI; Kehong YAN; Shuhuo ZHAO

    2007-01-01

    Inorganic tubular nanostructure MS2 (M=Mo, W, Nb, Ta) were synthesized by two alternative routes. Thermal decomposition method was used for producing fullerence-like MS2 (M=Mo, W) nanotubes on Al2O3 template using ammonium sulfur respectively; NbS2, and TaS2 nanotubes were obtained successfully by reducing corresponding metal trisulfide in a stream of H2 (mixed with N2 in some cases) at elevated temperatures.Detailed experimental procedure, and the characterization of associated results, were evaluated using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). The result reveals that products are composed of high density of MS2 tubular nanostructures with the diameter of 100 nm and length of tens of micrometers. And no mistake, these 1-D (one-dimensional) tubular nanomaterials added quantities and varieties in the growing family of nanotubes of inorganic layered materials.

  5. Origins of life: a route to nanotechnology.

    Science.gov (United States)

    Sowerby, S J; Holm, N G; Petersen, G B

    2001-06-01

    The origins of life and nanotechnology are two seemingly disparate areas of scientific investigation. However, the fundamental questions of life's beginnings and the applied construction of a Drexlerian nanotechnology both share a similar problem; how did and how can self-reproducing molecular machines originate? Here we draw attention to the coincidence between nanotechnology and origins research with particular attention paid to the spontaneous adsorption and scanning tunneling microscopy investigation of purine and pyrimidine bases self-organized into monolayers, adsorbed to the surfaces of crystalline solids. These molecules which encode biological information in nucleic acids, can form supramolecular architectures exhibiting enantiomorphism with the complexity to store and encode putative protobiological information. We conclude that the application of nanotechnology to the investigation of life's origins, and vice versa, could provide a viable route to an evolution-driven synthetic life.

  6. Clinical assessment for three routes of hysterectomy

    Institute of Scientific and Technical Information of China (English)

    ZHU Lan; LANG Jing-he; LIU Chun-yan; SHI Hong-hui; SUN Zhi-jing; FAN Rong

    2009-01-01

    Background Hysterectomy is a very common surgery in gynecology. Ideal surgery for hysterectomy is microinvasive with few complications. There are three major routes of hysterectomy that are currently used. The aim of this study was to identify the differences of peri-operative outcome among the patients who underwent the three different approaches.Methods One hundred and one women undergoing hysterectomy for myoma had the procedure performed by laparoscopic assisted vaginal hysterectomy (LAVH), total vaginal hysterectomy (TVH) or total abdominal hysterectomy (TAH) in a randomized study. We compared the course of peri-operative and post-operative outcome for the three different approaches. Results were evaluated by linear regression analysis, Fishers exact test and Student's t test for independent samples.Results The operation time among the three procedures was not significantly different (P >0.05). The amount of blood loss in the TVH group was less than in the LAVH and TAH groups (P<0.05). The pain score 3 hours after operation in the LAVH group was significantly lower than in the TAH and TVH groups (P<0.001). The pain scores in the LAVH and TVH groups were lower than in the TAH group at 24 and 48 hours after operation (P<0.01). The women who underwent LAVH and TVH had a shorter hospitalization stay (P <0.001). The highest body temperature after operation in the TAH group was higher than that in LAVH and TVH groups (P <0.001).Conclusions LAVH and TVH are better procedures for women requiring hysterectomy. The peri-operative and post-operative courses of TVH are better than LAVH, excluding the pain score 3 hours after operation. Vaginal hysterectomy is the most cost-effective approach but the final choice for the route of hysterectomy can depend on many factors such as gynecological disease, patients' health status and experiences of the gynecologist.

  7. Optimization of the imported air express cargo distribution problem

    Directory of Open Access Journals (Sweden)

    Hwang, T.L.

    2013-03-01

    Full Text Available This study examines the delivering network of imported air express cargo as an integrated multi-depot vehicle routing problem. Integrated multi-depot vehicle routing problem attempts to decide which service centers should be used and how much freight should be unloaded in each service center. The role of an exchange point which is allowing the delivery vans and shuttles to exchange imported and exported goods is also addressed. Test results demonstrate the feasibility of the four models so these are highly promising for use in a diverse array of applications, such as in home delivery and reverse logistics.

  8. Development and Application of a Next Generation Air Sensor Network for the Hong Kong Marathon 2015 Air Quality Monitoring

    Directory of Open Access Journals (Sweden)

    Li Sun

    2016-02-01

    Full Text Available This study presents the development and evaluation of a next generation air monitoring system with both laboratory and field tests. A multi-parameter algorithm was used to correct for the impact of environmental conditions on the electrochemical sensors for carbon monoxide (CO and nitrogen dioxide (NO2 pollutants. The field evaluation in an urban roadside environment in comparison to designated monitors showed good agreement with measurement error within 5% of the pollutant concentrations. Multiple sets of the developed system were then deployed in the Hong Kong Marathon 2015 forming a sensor-based network along the marathon route. Real-time air pollution concentration data were wirelessly transmitted and the Air Quality Health Index (AQHI for the Green Marathon was calculated, which were broadcast to the public on an hourly basis. The route-specific sensor network showed somewhat different pollutant patterns than routine air monitoring, indicating the immediate impact of traffic control during the marathon on the roadside air quality. The study is one of the first applications of a next generation sensor network in international sport events, and it demonstrated the usefulness of the emerging sensor-based air monitoring technology in rapid network deployment to supplement existing air monitoring.

  9. Development and Application of a Next Generation Air Sensor Network for the Hong Kong Marathon 2015 Air Quality Monitoring.

    Science.gov (United States)

    Sun, Li; Wong, Ka Chun; Wei, Peng; Ye, Sheng; Huang, Hao; Yang, Fenhuan; Westerdahl, Dane; Louie, Peter K K; Luk, Connie W Y; Ning, Zhi

    2016-02-05

    This study presents the development and evaluation of a next generation air monitoring system with both laboratory and field tests. A multi-parameter algorithm was used to correct for the impact of environmental conditions on the electrochemical sensors for carbon monoxide (CO) and nitrogen dioxide (NO2) pollutants. The field evaluation in an urban roadside environment in comparison to designated monitors showed good agreement with measurement error within 5% of the pollutant concentrations. Multiple sets of the developed system were then deployed in the Hong Kong Marathon 2015 forming a sensor-based network along the marathon route. Real-time air pollution concentration data were wirelessly transmitted and the Air Quality Health Index (AQHI) for the Green Marathon was calculated, which were broadcast to the public on an hourly basis. The route-specific sensor network showed somewhat different pollutant patterns than routine air monitoring, indicating the immediate impact of traffic control during the marathon on the roadside air quality. The study is one of the first applications of a next generation sensor network in international sport events, and it demonstrated the usefulness of the emerging sensor-based air monitoring technology in rapid network deployment to supplement existing air monitoring.

  10. Enhanced Contact Graph Routing (ECGR) MACHETE Simulation Model

    Science.gov (United States)

    Segui, John S.; Jennings, Esther H.; Clare, Loren P.

    2013-01-01

    Contact Graph Routing (CGR) for Delay/Disruption Tolerant Networking (DTN) space-based networks makes use of the predictable nature of node contacts to make real-time routing decisions given unpredictable traffic patterns. The contact graph will have been disseminated to all nodes before the start of route computation. CGR was designed for space-based networking environments where future contact plans are known or are independently computable (e.g., using known orbital dynamics). For each data item (known as a bundle in DTN), a node independently performs route selection by examining possible paths to the destination. Route computation could conceivably run thousands of times a second, so computational load is important. This work refers to the simulation software model of Enhanced Contact Graph Routing (ECGR) for DTN Bundle Protocol in JPL's MACHETE simulation tool. The simulation model was used for performance analysis of CGR and led to several performance enhancements. The simulation model was used to demonstrate the improvements of ECGR over CGR as well as other routing methods in space network scenarios. ECGR moved to using earliest arrival time because it is a global monotonically increasing metric that guarantees the safety properties needed for the solution's correctness since route re-computation occurs at each node to accommodate unpredicted changes (e.g., traffic pattern, link quality). Furthermore, using earliest arrival time enabled the use of the standard Dijkstra algorithm for path selection. The Dijkstra algorithm for path selection has a well-known inexpensive computational cost. These enhancements have been integrated into the open source CGR implementation. The ECGR model is also useful for route metric experimentation and comparisons with other DTN routing protocols particularly when combined with MACHETE's space networking models and Delay Tolerant Link State Routing (DTLSR) model.

  11. CulRoute: Gamified WebGIS3D platform for selection of touristic routes

    Directory of Open Access Journals (Sweden)

    E.P.L. Baptista

    2015-11-01

    Full Text Available The importance of tourist information disclosure on digital platforms is, nowadays, reinforced by public entities such as Turismo de Portugal and Turismo do Algarve. The incorporation of strategies to encourage greater interest and involvement of the users are likely to contribute to a more effective dissemination of tourist destinations and their historical and cultural heritage. This paper presents the concepts, strategies and technologies in the design and implementation of the gamified WebGIS3D platform named CulRoute. This platform enables the users to visualize and navigate the three-dimensional virtual models of monuments and to explore the 'treasures' of each monument in a gaming environment, as well as to test their knowledge by answering optional quizzes. From the list of visited monuments and other information available on the platform, the user can create customized routes, save them into files or print as maps for later use.

  12. A Study on Selecting the Shortest Routes by Voronoi Diagram in Route Networks of GIS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The problems of fast determining shortest paths through a polygonal subdivisionplanar with n vertices are considered in GIS. Distances are measured according to an Euclideanmetric. A geographical information system (GIS)has a collection of nearest neighborhoodoperations and this collection serves as a useful toolbox for spatial analysis. These operationsare undertaken through the Voronoi diagrams. This paper presents a novel algorithm thatconstructs a “shortest route set” with respect to a given source point and a target point byVoronoi diagrams. It will help to improve the efficiency of traditional algorithms, e. g. , Djkstraalgorithm, on selecting the shortest routes. Moreover, the novel algorithm can check theconnectivity in a complex network between the source point and target one.

  13. Multi-path Routing Metrics for Reliable Wireless Mesh Routing Topologies

    CERN Document Server

    Chen, Phoebus; Balister, Paul; Bollobás, Béla; Sastry, Shankar

    2011-01-01

    Several emerging classes of applications that run over wireless networks have a need for mathematical models and tools to systematically characterize the reliability of the network. We propose two metrics for measuring the reliability of wireless mesh routing topologies, one for flooding and one for unicast routing. The Flooding Path Probability (FPP) metric measures the end-to-end packet delivery probability when each node broadcasts a packet after hearing from all its upstream neighbors. The Unicast Retransmission Flow (URF) metric measures the end-to-end packet delivery probability when a relay node retransmits a unicast packet on its outgoing links until it receives an acknowledgement or it tries all the links. Both metrics rely on specific packet forwarding models, rather than heuristics, to derive explicit expressions of the end-to-end packet delivery probability from individual link probabilities and the underlying connectivity graph. We also propose a distributed, greedy algorithm that uses the URF me...

  14. Air filtration and indoor air quality

    DEFF Research Database (Denmark)

    Bekö, Gabriel

    2006-01-01

    decent ventilation and air cleaning/air filtration, high indoor air quality cannot be accomplished. The need for effective air filtration has increased with increasing evidence on the hazardous effects of fine particles. Moreover, the air contains gaseous pollutants, removal of which requires various air....... These contradictions should motivate manufacturers and researchers to develop new efficient filtration techniques and/or improve the existing ones. Development of low polluting filtration techniques, which are at the same time easy and inexpensive to maintain is the way forward in the future....

  15. Nature-Inspired and Energy Efficient Route Planning

    DEFF Research Database (Denmark)

    Schlichtkrull, Anders; Christensen, J. B. S.; Feld, T.

    2015-01-01

    Cars are responsible for substantial CO2 emission worldwide. Computers can help solve this problem by computing shortest routes on maps. A good example of this is the popular Google Maps service. However, such services often require the order of the stops on the route to be fixed. By not enforcing...

  16. Cost Effectiveness of Alternative Route Special Education Teacher Preparation

    Science.gov (United States)

    Sindelar, Paul T.; Dewey, James F.; Rosenberg, Michael S.; Corbett, Nancy L.; Denslow, David; Lotfinia, Babik

    2012-01-01

    In this study, the authors estimated costs of alternative route preparation to provide states a basis for allocating training funds to maximize production. Thirty-one special education alternative route program directors were interviewed and completed cost tables. Two hundred and twenty-four program graduates were also surveyed. The authors…

  17. Leapfrog: Optimal opportunistic Routing in Probabilistically Contacted Delay Tolerant Networks

    Institute of Scientific and Technical Information of China (English)

    Ming-Jun Xiao; Liu-Sheng Huang; Qun-Feng Dong; An Liu; Zhen-Guo Yang

    2009-01-01

    Delay tolerant networks (DTNs)experience frequent and long lasting network disconnection due to various reasons such as mobility.power management.and scheduling.One primary concern in DTNs is to route messages to keep the end-to-end delivery delay as low as possible.In this paper,we study the single-copy message routing problem and propose an optimal opportunistic routing strategy--Leapfrog Routing--for probabilistically contacted DTNs where nodes encounter or contact in some fixed probabilities.We deduce the iterative computation formulate of minimum expected opportunistic delivery delay from each node to the destination and discover that under the optimal opportunistic routing strategy,messages would be delivered from high-delay node to low-delay node in the leapfrog manner.Rigorous theoretical analysis shows that such a routing strategy is exactly the optimal among all possible ones.Moreover,we apply the idea of Reverse Dijkstra algorithm to design an algorithm.When a destination iS given,this algorithm can determine for each node the routing selection function under the Leapfrog Routing strategy.The computation overhead of this algorithm is only O(n~2) where n is the number of nodes in the network.In addition,through extensive simulations based on real DTN traces,we demonstrate that our algorithm can significantly outperform the previous ones.

  18. Dynamic vehicle routing with time windows in theory and practice

    NARCIS (Netherlands)

    Yang, Z.; Osta, van J.P.; Veen, van B.; Krevelen, van R.; Stam, A.; Kok, J.N.; Bäck, T.H.W.; Michael, Emmerich T. M.

    2016-01-01

    The vehicle routing problem is a classical combinatorial optimization problem. This work is about a variant of the vehicle routing problem with dynamically changing orders and time windows. In real-world applications often the demands change during operation time. New orders occur and others are can

  19. 14 CFR 121.121 - En route navigation facilities.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false En route navigation facilities. 121.121 Section 121.121 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Operations § 121.121 En route navigation facilities. (a) Except as provided in paragraph (b) of this...

  20. 14 CFR 121.103 - En route navigation facilities.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false En route navigation facilities. 121.103 Section 121.103 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... § 121.103 En route navigation facilities. (a) Except as provided in paragraph (b) of this section,...