Iron-Induced Activation of Ordered Mesoporous Nickel Cobalt Oxide Electrocatalyst for the Oxygen Evolution Reaction.

Science.gov (United States)

Deng, Xiaohui; Öztürk, Secil; Weidenthaler, Claudia; Tüysüz, Harun

2017-06-28

Herein, ordered mesoporous nickel cobalt oxides prepared by the nanocasting route are reported as highly active oxygen evolution reaction (OER) catalysts. By using the ordered mesoporous structure as a model system and afterward elevating the optimal catalysts composition, it is shown that, with a simple electrochemical activation step, the performance of nickel cobalt oxide can be significantly enhanced. The electrochemical impedance spectroscopy results indicated that charge transfer resistance increases for Co 3 O 4 spinel after an activation process, while this value drops for NiO and especially for CoNi mixed oxide significantly, which confirms the improvement of oxygen evolution kinetics. The catalyst with the optimal composition (Co/Ni 4/1) reaches a current density of 10 mA/cm 2 with an overpotential of a mere 336 mV and a Tafel slope of 36 mV/dec, outperforming benchmarked and other reported Ni/Co-based OER electrocatalysts. The catalyst also demonstrates outstanding durability for 14 h and maintained the ordered mesoporous structure. The cyclic voltammograms along with the electrochemical measurements in Fe-free KOH electrolyte suggest that the activity boost is attributed to the generation of surface Ni(OH) 2 species that incorporate Fe impurities from the electrolyte. The incorporation of Fe into the structure is also confirmed by inductively coupled plasma optical emission spectrometry.

Route of administration of pentobarbital affects activity of liver glycogen phosphorylase

DEFF Research Database (Denmark)

Mikines, K J; Sonne, B; Richter, Erik

1986-01-01

pentobarbital (5 mg/100 g body wt) either intraperitoneally, as a slow intravenous infusion, or as an intravenous or intracardial bolus. Times from administration of barbiturate to sampling of the liver were 10 min, 10 min, 85 +/- 32 s (mean +/- SE), and 53 +/- 10 s, respectively. Phosphorylase a activity...... in % of total phosphorylase activity was 40 +/- 2, 56 +/- 4, 82 +/- 3, and 92 +/- 2, respectively, all significantly different. Thus the route of administration of pentobarbital affects the phosphorylase a activity and should be considered when evaluating this activity. This fact can only be partially explained...

Effect of the Northern Sea Route Opening to the Shipping Activities at Malacca Straits

Directory of Open Access Journals (Sweden)

N.S.F. Abdul Rahman

2014-12-01

Full Text Available The opening of the Northern Sea Route as an alternative route for transporting cargoes between the Far East and Europe seems highly acceptable by shipping companies due to the great saving in fuel consumption, bunker cost, operating cost, emissions and journey time. This situation will not only affect the maritime business activity in the Straits of Malacca but also, the Malaysian economy in different perspectives when the vessels sail via the Suez Canal and the Indian Ocean are expected to decrease. The objective of this study is to analyse the implication in the opening of the Northern Sea Route on Maritime Sector of the Malaysian economy by using PESTEL analysis. The main scope is focusing more on the Malacca Straits shipping activity by using a number of parameters that have been obtained from Port Klang and Port Klang Authority through a set of questionnaires and interview sessions with industrial experts.

Energy Efficient Routing and Node Activity Scheduling in the OCARI Wireless Sensor Network

Directory of Open Access Journals (Sweden)

Saoucene Mahfoudh

2010-08-01

Full Text Available Sensor nodes are characterized by a small size, a low cost, an advanced communication technology, but also a limited amount of energy. Energy efficient strategies are required in such networks to maximize network lifetime. In this paper, we focus on a solution integrating energy efficient routing and node activity scheduling. The energy efficient routing we propose, called EOLSR, selects the route and minimizes the energy consumed by an end-to-end transmission, while avoiding nodes with low residual energy. Simulation results show that EOLSR outperforms the solution selecting the route of minimum energy as well as the solution based on node residual energy. Cross-layering allows EOLSR to use information from the application layer or the MAC layer to reduce its overhead and increase network lifetime. Node activity scheduling is based on the following observation: the sleep state is the least power consuming state. So, to schedule node active and sleeping periods, we propose SERENA that colors all network nodes using a small number of colors, such that two nodes with the same color can transmit without interfering. The node color is mapped into a time slot during which the node can transmit. Consequently, each node is awake during its slot and the slots of its one-hop neighbors, and sleeps in the remaining time. We evaluate SERENA benefits obtained in terms of bandwidth, delay and energy. We also show how cross-layering with the application layer can improve the end-to-end delays for data gathering applications.

Tourist activated networks: Implications for dynamic bundling and en-route recommendations

DEFF Research Database (Denmark)

Zach, Florian; Gretzel, Ulrike

2011-01-01

This article discusses tourist-activated networks as a concept to inform technological applications supporting dynamic bundling and en route recommendations. Empirical data were collected from travelers who visited a regional destination in the US and then analyzed with respect to its network...... structure. The results indicate that the tourist-activated network for the destination is rather sparse and that there are clearly differences in core and peripheral nodes. The findings illustrate the structure of a tourist-activated network and provide implications for technology design and tourism...

A social activity and physical contact-based routing algorithm in mobile opportunistic networks for emergency response to sudden disasters

Science.gov (United States)

Wang, Xiaoming; Lin, Yaguang; Zhang, Shanshan; Cai, Zhipeng

2017-05-01

Sudden disasters such as earthquake, flood and hurricane necessitate the employment of communication networks to carry out emergency response activities. Routing has a significant impact on the functionality, performance and flexibility of communication networks. In this article, the routing problem is studied considering the delivery ratio of messages, the overhead ratio of messages and the average delay of messages in mobile opportunistic networks (MONs) for enterprise-level emergency response communications in sudden disaster scenarios. Unlike the traditional routing methods for MONS, this article presents a new two-stage spreading and forwarding dynamic routing algorithm based on the proposed social activity degree and physical contact factor for mobile customers. A new modelling method for describing a dynamic evolving process of the topology structure of a MON is first proposed. Then a multi-copy spreading strategy based on the social activity degree of nodes and a single-copy forwarding strategy based on the physical contact factor between nodes are designed. Compared with the most relevant routing algorithms such as Epidemic, Prophet, Labelled-sim, Dlife-comm and Distribute-sim, the proposed routing algorithm can significantly increase the delivery ratio of messages, and decrease the overhead ratio and average delay of messages.

Thermally Activated Delayed Fluorescence in Polymers: A New Route toward Highly Efficient Solution Processable OLEDs.

Science.gov (United States)

Nikolaenko, Andrey E; Cass, Michael; Bourcet, Florence; Mohamad, David; Roberts, Matthew

2015-11-25

Efficient intermonomer thermally activated delayed fluorescence is demonstrated for the first time, opening a new route to achieving high-efficiency solution processable polymer light-emitting device materials. External quantum efficiency (EQE) of up to 10% is achieved in a simple fully solution-processed device structure, and routes for further EQE improvement identified. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

An efficient route for catalytic activity promotion via hybrid electro-depositional modification on commercial nickel foam for hydrogen evolution reaction in alkaline water electrolysis

Energy Technology Data Exchange (ETDEWEB)

Ma, Guanshui; He, Yongwei; Wang, Mei; Zhu, Fuchun; Tang, Bin [Research Institute of Surface Engineering, Taiyuan University of Technology, Yingze West Road 79, Taiyuan 030024 (China); Wang, Xiaoguang, E-mail: wangxiaog1982@163.com [Research Institute of Surface Engineering, Taiyuan University of Technology, Yingze West Road 79, Taiyuan 030024 (China); International Iberian Nanotechnology Laboratory (INL), 4715-330 Braga (Portugal)

2014-09-15

Highlights: • Mono-Cu surface modification depress the HER activity of Ni-foam. • Hybrid Ni-foam/Cu0.01/Co0.05 exhibits superior HER performance. • Layer-by-layer structure may contribute to a synergistic promoting effect. - Abstract: In this paper, the single- and hybrid-layered Cu, Ni and Co thin films were electrochemically deposited onto the three-dimensional nickel foam as composite cathode catalyst for hydrogen evolution reaction in alkaline water electrolysis. The morphology, structure and chemical composition of the electrodeposited composite catalysts were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). Electrochemical measurement depicted that, for the case of the monometallic layered samples, the general activity for hydrogen evolution reaction followed the sequence: Ni-foam/Ni > Ni-foam/Co > bare Ni-foam > Ni-foam/Cu. It is noteworthy that, the hybrid-layered Ni-foam/Cu0.01/Co0.05 exhibited the highest catalytic activity towards hydrogen evolution reaction with the current density as high as 2.82 times that of the bare Ni-foam. Moreover, both excellent electrochemical and physical stabilities can also be acquired on the Ni-foam/Cu0.01/Co0.05, making this hybrid-layered composite structure as a promising HER electro-catalyst.

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,

INNOVATIONS AND TOURISTIC ACTIVITY EVOLUTION

Directory of Open Access Journals (Sweden)

V. S. Novikov

2012-01-01

Full Text Available Fundamental and applied innovations impact activities in the tourist industry and evolution thereof. More and more sophisticated technologies and communication techniques are practically used to serve tourists. Basically, innovative tourist activity development concept represents innovation of values and in particular means that tourist’s impression is taken into account to higher extent and tourist product personification changes the products’ consumer value. Discussed in the article are tourist activity, tourist cluster, destination and glocalization development prospects.

Decolonial turn on heritage? Liberation Heritage Route as a postcolonial alternative of patrimonial activation

Directory of Open Access Journals (Sweden)

Ester Massó Guijarro

2017-05-01

Full Text Available Considering the decolonial turn as a key epistemological axis for troubling heritage, the Liberation Heritage Route in South Africa is brought up as a discursive example, as a unique type of patrimonial activation where heritage (collective memory is linked to the struggle of a people for their rights, beyond etÚic or national folklore. It will try to show how the Liberation Heritage Route —as a case study— implies a living and notorious example of the very conceptual challenge of this work: it is a subaltern heritage (or shows a pathway for heritage's subalternization and most especially, it is a patent form of holistic heritage activation, where the tangible and the intangible, the physical and symbolic, monumental and spiritual, come together in a unique and indivisible product at the service of justice and dignity.

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 ...

Iconic memory-based omnidirectional route panorama navigation.

Science.gov (United States)

Yagi, Yasushi; Imai, Kousuke; Tsuji, Kentaro; Yachida, Masahiko

2005-01-01

A route navigation method for a mobile robot with an omnidirectional image sensor is described. The route is memorized from a series of consecutive omnidirectional images of the horizon when the robot moves to its goal. While the robot is navigating to the goal point, input is matched against the memorized spatio-temporal route pattern by using dual active contour models and the exact robot position and orientation is estimated from the converged shape of the active contour models.

Factors regulating nitrogenase activity and hydrogen evolution in Azolla-Anabaena symbiosis

Energy Technology Data Exchange (ETDEWEB)

Banerjee, M.; Kumar, A.; Kumar, H.D. (Banaras Hindu Univ., Varanasi (India). Dept. of Botany)

1989-01-01

Nitrogenase activity and H{sub 2} production capacity have been studied in intact Azolla plants. Under aerobic conditions the plants showed a C{sub 2}H{sub 2} reduction rate of 6.65 nmoles C{sub 2}H{sub 4} mg {sup -1} fresh weight in light at 48 h. Considerable activity was also present in the dark. Though H{sub 2} evolution was detected under aerobic conditions there was multifold stimulation under anaerobic conditions. There was no significant change in nitrogenase activity under anaerobic conditions. Increasing concentrations of O{sub 2} inhibited nitrogenase activity but 5% O{sub 2} proved stimulatory for H{sub 2} evolution in light. In the dark, there was a gradual stimulation in H{sub 2} evolution even up to 20% O{sub 2}. The addition of combined nitrogen sources, namely NH{sub 4}Cl or KNO{sub 3} (10 mM), resulted in complete inhibition of the C{sub 2}H{sub 2}-reduction activity within 48 h, but H{sub 2} evolution was not inhibited. Indeed, these combined nitrogen sources stimulated H{sub 2} evolution. Though nitrogenase activity was affected, the heterocyst frequency remained unaltered. Phosphate addition resulted in significant stimulation of nitrogenase and H{sub 2} evolution activity. These results suggest that nitrogenase and H{sub 2} evolution activity in Azolla are affected by a number of factors which show a differential effect on nitrogenase and H{sub 2} evolution. Furthermore, our results indicate the presence of a soluble reversible hydrogenase in Azolla. (author).

Parallel Evolution of Sperm Hyper-Activation Ca2+ Channels.

Science.gov (United States)

Cooper, Jacob C; Phadnis, Nitin

2017-07-01

Sperm hyper-activation is a dramatic change in sperm behavior where mature sperm burst into a final sprint in the race to the egg. The mechanism of sperm hyper-activation in many metazoans, including humans, consists of a jolt of Ca2+ into the sperm flagellum via CatSper ion channels. Surprisingly, all nine CatSper genes have been independently lost in several animal lineages. In Drosophila, sperm hyper-activation is performed through the cooption of the polycystic kidney disease 2 (pkd2) Ca2+ channel. The parallels between CatSpers in primates and pkd2 in Drosophila provide a unique opportunity to examine the molecular evolution of the sperm hyper-activation machinery in two independent, nonhomologous calcium channels separated by > 500 million years of divergence. Here, we use a comprehensive phylogenomic approach to investigate the selective pressures on these sperm hyper-activation channels. First, we find that the entire CatSper complex evolves rapidly under recurrent positive selection in primates. Second, we find that pkd2 has parallel patterns of adaptive evolution in Drosophila. Third, we show that this adaptive evolution of pkd2 is driven by its role in sperm hyper-activation. These patterns of selection suggest that the evolution of the sperm hyper-activation machinery is driven by sexual conflict with antagonistic ligands that modulate channel activity. Together, our results add sperm hyper-activation channels to the class of fast evolving reproductive proteins and provide insights into the mechanisms used by the sexes to manipulate sperm behavior. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Spectral-luminosity evolution of active galactic nuclei (AGN)

Science.gov (United States)

Leiter, Darryl; Boldt, Elihu

1992-01-01

The origin of the cosmic X-ray and gamma-ray backgrounds is explained via the mechanism of AGN spectral-luminosity evolution. The spectral evolution of precursor active galaxies into AGN, and Newton-Raphson input and output parameters are discussed.

Highway route controlled quantity shipment routing reports - An overview

International Nuclear Information System (INIS)

Cashwell, J.W.; Welles, B.W.; Welch, M.J.

1989-01-01

US Department of Transportation (DOT) regulations require a postnotification report from the shipper for all shipments of radioactive materials categorized as a Highway Route Controlled Quantity. These postnotification reports, filed in compliance with 49 CFR 172.203(d), have been compiled by the DOT in a database known as the Radioactive Materials Routing Report (RAMRT) since 1982. The data were sorted by each of its elements to establish historical records and trends of Highway Route Controlled Quantity shipments from 1982 through 1987. Approximately 1520 records in the RAMRT database were compiled for this analysis. Approximately half of the shipments reported for the study period were from the US Department of Energy (DOE) and its contractors, with the others being commercial movements. Two DOE installations, EG and G Idaho and Oak Ridge, accounted for nearly half of the DOE activities. Similarly, almost half of the commercial movements were reported by two vendors, Nuclear Assurance Corporation and Transnuclear, Incorporated. Spent fuel from power and research reactors accounted for approximately half of all shipments

A Simulation-Based Dynamic Stochastic Route Choice Model for Evacuation

Directory of Open Access Journals (Sweden)

Xing Zhao

2012-01-01

Full Text Available This paper establishes a dynamic stochastic route choice model for evacuation to simulate the propagation process of traffic flow and estimate the stochastic route choice under evacuation situations. The model contains a lane-group-based cell transmission model (CTM which sets different traffic capacities for links with different turning movements to flow out in an evacuation situation, an actual impedance model which is to obtain the impedance of each route in time units at each time interval and a stochastic route choice model according to the probit-based stochastic user equilibrium. In this model, vehicles loading at each origin at each time interval are assumed to choose an evacuation route under determinate road network, signal design, and OD demand. As a case study, the proposed model is validated on the network nearby Nanjing Olympic Center after the opening ceremony of the 10th National Games of the People's Republic of China. The traffic volumes and clearing time at five exit points of the evacuation zone are calculated by the model to compare with survey data. The results show that this model can appropriately simulate the dynamic route choice and evolution process of the traffic flow on the network in an evacuation situation.

DARAL: A Dynamic and Adaptive Routing Algorithm for Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Francisco José Estévez

2016-06-01

Full Text Available The evolution of Smart City projects is pushing researchers and companies to develop more efficient embedded hardware and also more efficient communication technologies. These communication technologies are the focus of this work, presenting a new routing algorithm based on dynamically-allocated sub-networks and node roles. Among these features, our algorithm presents a fast set-up time, a reduced overhead and a hierarchical organization, which allows for the application of complex management techniques. This work presents a routing algorithm based on a dynamically-allocated hierarchical clustering, which uses the link quality indicator as a reference parameter, maximizing the network coverage and minimizing the control message overhead and the convergence time. The present work based its test scenario and analysis in the density measure, considered as a node degree. The routing algorithm is compared with some of the most well known routing algorithms for different scenario densities.

Fatigue mitigation effects of en-route napping on commercial airline pilots flying international routes

Science.gov (United States)

Baldwin, Jarret Taylor

The introduction of ultra-long range commercial aircraft and the evolution of the commercial airline industry has provided new opportunities for air carriers to fly longer range international route segments while deregulation, industry consolidation, and the constant drive to reduce costs wherever possible has pressured airline managements to seek more productivity from their pilots. At the same time, advancements in the understanding of human physiology have begun to make their way into flight and duty time regulations and airline scheduling practices. In this complex and ever changing operating environment, there remains an essential need to better understand how these developments, and other daily realities facing commercial airline pilots, are affecting their fatigue management strategies as they go about their rituals of getting to and from their homes to work and performing their flight assignments. Indeed, the need for commercial airline pilots to have access to better and more effective fatigue mitigation tools to combat fatigue and insure that they are well rested and at the top of their game when flying long-range international route segments has never been greater. This study examined to what extent the maximum fatigue states prior to napping, as self-accessed by commercial airline pilots flying international route segments, were affected by a number of other common flight assignment related factors. The study also examined to what extent the availability of scheduled en-route rest opportunities, in an onboard crew rest facility, affected the usage of en-route napping as a fatigue mitigation strategy, and to what extent the duration of such naps affected the perceived benefits of such naps as self-accessed by commercial airline pilots flying international route segments. The study utilized an online survey tool to collect data on crew position, prior flight segments flown in the same duty period, augmentation, commuting, pre-flight rest obtained in the

Evolution of the outflow activity of protostars

International Nuclear Information System (INIS)

Bontemps, Sylvain

1996-01-01

After a first part describing the formation of low-mass stars (sites of stellar formation, protostellar evolution) and matter outflows from young objects (molecular flows and their origin, optical and radio jets, outflow mechanisms), this research thesis discusses the evolution of molecular flows by reprinting a published article (Evolution of outflow activity around low-mass embedded young stellar objects), and by outlining some remaining issues (differences between clouds of stellar formation, morphological evolution of molecular flows). The author then discusses the continuous radio centimetre emission: origin, systematic search for Class 0 objects by using the VLA (Very Large Array radio interferometer), presentation of a new Class 0 protostar (HH24MMS). The author reports the study of H_2 emission in the infrared: generalities on protostellar shocks, infrared jet by HH24MMS, H_2 emission at 10 microns by using the ISOCAM camera [fr

Energy Efficient MANET Routing Using a Combination of Span and BECA/AFECA

DEFF Research Database (Denmark)

Kristensen, Mads Darø; Bouvin, Niels Olof

2008-01-01

This paper presents some novel approaches for energy efficient routing in mobile ad-hoc networks. Two known energy preserving techniques, Span and BECA/AFECA, are combined with a well-known re-active routing protocol, AODV, to create a new energy efficient routing protocol. Furthermore, the proto......This paper presents some novel approaches for energy efficient routing in mobile ad-hoc networks. Two known energy preserving techniques, Span and BECA/AFECA, are combined with a well-known re-active routing protocol, AODV, to create a new energy efficient routing protocol. Furthermore...

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.

Crossing Active Faults on the Sakhalin II Onshore Pipeline Route: Analysis Methodology and Basic Design

International Nuclear Information System (INIS)

Vitali, Luigino; Mattiozzi, Pierpaolo

2008-01-01

Twin oil (20 and 24 inch) and gas (20 and 48 inch) pipeline systems stretching 800 km are being constructed to connect offshore hydrocarbon deposits from the Sakhalin II concession in the North to an LNG plant and oil export terminal in the South of Sakhalin island. The onshore pipeline route follows a regional fault zone and crosses individual active faults at 19 locations. Sakhalin Energy, Design and Construction companies took significant care to ensure the integrity of the pipelines, should large seismic induced ground movements occur during the Operational life of the facilities. Complex investigations including the identification of the active faults, their precise location, their particular displacement values and assessment of the fault kinematics were carried out to provide input data for unique design solutions. Lateral and reverse offset displacements of 5.5 and 4.5 m respectively were determined as the single-event values for the design level earthquake (DLE)--the 1000-year return period event. Within the constraints of a pipeline route largely fixed, the underground pipeline fault crossing design was developed to define the optimum routing which would minimize stresses and strain using linepipe materials which had been ordered prior to the completion of detailed design, and to specify requirements for pipe trenching shape, materials, drainage system, etc. This Paper describes the steps followed to formulate the concept of the special trenches and the analytical characteristics of the Model

Crossing Active Faults on the Sakhalin II Onshore Pipeline Route: Pipeline Design and Risk Analysis

International Nuclear Information System (INIS)

Mattiozzi, Pierpaolo; Strom, Alexander

2008-01-01

Twin oil (20 and 24 inch) and gas (20 and 48 inch) pipeline systems stretching 800 km are being constructed to connect offshore hydrocarbon deposits from the Sakhalin II concession in the North to an LNG plant and oil export terminal in the South of Sakhalin island. The onshore pipeline route follows a regional fault zone and crosses individual active faults at 19 locations. Sakhalin Energy, Design and Construction companies took significant care to ensure the integrity of the pipelines, should large seismic induced ground movements occur during the Operational life of the facilities. Complex investigations including the identification of the active faults, their precise location, their particular displacement values and assessment of the fault kinematics were carried out to provide input data for unique design solutions. Lateral and reverse offset displacements of 5.5 and 4.5 m respectively were determined as the single-event values for the design level earthquake (DLE) - the 1000-year return period event. Within the constraints of a pipeline route largely fixed, the underground pipeline fault crossing design was developed to define the optimum routing which would minimize stresses and strain using linepipe materials which had been ordered prior to the completion of detailed design, and to specify requirements for pipe trenching shape, materials, drainage system, etc. Detailed Design was performed with due regard to actual topography and to avoid the possibility of the trenches freezing in winter, the implementation of specific drainage solutions and thermal protection measures

The evolution of flaring and non-flaring active regions

Science.gov (United States)

Kilcik, A.; Yurchyshyn, V.; Sahin, S.; Sarp, V.; Obridko, V.; Ozguc, A.; Rozelot, J. P.

2018-06-01

According to the modified Zurich classification, sunspot groups are classified into seven different classes (A, B, C, D, E, F and H) based on their morphology and evolution. In this classification, classes A and B, which are small groups, describe the beginning of sunspot evolution, while classes D, E and F describe the large and evolved groups. Class C describes the middle phase of sunspot evolution and the class H describes the end of sunspot evolution. Here, we compare the lifetime and temporal evolution of flaring and non-flaring active regions (ARs), and the flaring effect on ARs in these groups in detail for the last two solar cycles (1996 through 2016). Our main findings are as follows: (i) Flaring sunspot groups have longer lifetimes than non-flaring ones. (ii) Most of the class A, B and C flaring ARs rapidly evolve to higher classes, while this is not applicable for non-flaring ARs. More than 50 per cent of the flaring A, B and C groups changed morphologically, while the remaining D, E, F and H groups did not change remarkably after the flare activity. (iii) 75 per cent of all flaring sunspot groups are large and complex. (iv) There is a significant increase in the sunspot group area in classes A, B, C, D and H after flaring activity. In contrast, the sunspot group area of classes E and F decreased. The sunspot counts of classes D, E and F decreased as well, while classes A, B, C and H showed an increase.

Intelligent routing protocol for ad hoc wireless network

Science.gov (United States)

Peng, Chaorong; Chen, Chang Wen

2006-05-01

mechanisms, which are used to control active route and reduce the traffic amount in the route discovery procedure. Finial, the numerical experiments are given to show the effectiveness of IRP routing protocol.

Harvesting solar light with crystalline carbon nitrides for efficient photocatalytic hydrogen evolution

KAUST Repository

Bhunia, Manas Kumar

2014-08-14

Described herein is the photocatalytic hydrogen evolution using crystalline carbon nitrides (CNs) obtained by supramolecular aggregation followed by ionic melt polycondensation (IMP) using melamine and 2,4,6-triaminopyrimidine as a dopant. The solid state NMR spectrum of 15N-enriched CN confirms the triazine as a building unit. Controlling the amount and arrangements of dopants in the CN structure can dramatically enhance the photocatalytic performance for H2 evolution. The polytriazine imide (PTI) exhibits the apparent quantum efficiency (AQE) of 15% at 400 nm. This method successfully enables a substantial amount of visible light to be harvested for H2 evolution, and provides a promising route for the rational design of a variety of highly active crystalline CN photocatalysts. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

Effect of variation in active route timeout and my route timeout on the performance of AODV-ETX protocol in mobile adhoc network

Science.gov (United States)

Purnomo, A.; Widyawan; Najib, W.; Hartono, R.; Hartatik

2018-03-01

Mobile adhoc network (MANET) consists of nodes that are independent. A node can communicate each other without the presence of network infrastructure. A node can act as a transmitter and receiver as well as a router. This research has been variation in active route timeout and my route timeout on the performance of AODV-ETX protocol in MANET. The AODV-ETX protocol is the AODV protocol that uses the ETX metric. Performance testing is done on the static node topology with 5 m x 5 m node grid model where the distance between nodes is 100 m and node topology that consists of 25 nodes moves randomly with a moving speed of 1.38 m/s in an area of 1500 m x 300 m. From the test result, on the static node, AODV protocol-ETX shows optimal performance at a value MRT and ART of 10 s and 15 s, but showed a stable performance in the value of MRT and ART ≥60 s, while in randomly moved node topology shows stable performance in the value of MRT and ART ≥80 s.

The planning illusion: Does active planning of a learning route support learning as well as learners think it does?

NARCIS (Netherlands)

Bonestroo, W.J.; de Jong, Anthonius J.M.

2012-01-01

Is actively planning one’s learning route through a learning domain beneficial for learning? Moreover, can learners accurately judge the extent to which planning has been beneficial for them? This study examined the effects of active planning on learning. Participants received a tool in which they

Simple synthetic route to manganese-containing nanowires with the spinel crystal structure

Energy Technology Data Exchange (ETDEWEB)

Yu, Lei; Zhang, Yan; Hudak, Bethany M.; Wallace, Damon K.; Kim, Doo Young; Guiton, Beth S.

2016-08-15

This report describes a new route to synthesize single-crystalline manganese-containing spinel nanowires (NWs) by a two-step hydrothermal and solid-state synthesis. Interestingly, a nanowire or nanorod morphology is maintained during conversion from MnO{sub 2}/MnOOH to CuMn{sub 2}O{sub 4}/Mg{sub 2}MnO{sub 4}, despite the massive structural rearrangement this must involve. Linear sweep voltammetry (LSV) curves of the products give preliminary demonstration that CuMn{sub 2}O{sub 4} NWs are catalytically active towards the oxygen evolution reaction (OER) in alkaline solution, exhibiting five times the magnitude of current density found with pure carbon black. - Highlights: • Synthesis of single-crystalline manganese-containing spinel nanowires. • Binary oxide nanowire converted to ternary oxide wire through solid state reaction. • Approach to structure conversion with shape retention could be generally applicable. • Copper and Manganese display multiple oxidation states with potential for catalysis. • CuMn{sub 2}O{sub 4} nanowires show promise as catalysts for the oxygen evolution reaction.

Effect of surface properties of NiFe2O4 nanoparticles synthesized by dc thermal plasma route on antimicrobial activity

Science.gov (United States)

Bhosale, S. V.; Ekambe, P. S.; Bhoraskar, S. V.; Mathe, V. L.

2018-05-01

The present work reports the role of surface properties of NiFe2O4 nanoparticles on the antimicrobial activity. The NiFe2O4 nanoparticles were synthesized by gas phase condensation and chemical co-precipitation route. These nanoparticles were extensively investigated using X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and electro-kinetic property measurements. The HRTEM was used to analyze surface morphology of nickel ferrite nanoparticles obtained by two different routes. Electro-kinetic properties of the nanoparticles under investigation were recorded, analyzed and correlated with the antimicrobial properties. It was observed that nickel ferrite nanoparticles synthesized by thermal plasma route (NFOTP) formed highly stable colloidal solution as compared to chemically synthesized (NFOCP), as the later tends to agglomerate due to low surface charge. The antimicrobial activity of NiFe2O4 nanoparticles were investigated on two Gram positive bacteria Staphylococcus aureus and Streptococcus pyogenes, two Gram negative bacteria Escherichia coli and Salmonella typhimurium and one fungal species Candida albicans. It was noted that the surface properties of NiFe2O4 particles have revealing effect on the antimicrobial activity. The NFOTP nanoparticles showed significant activity for gram negative E. coli bacteria however no activity was observed for other bacteria's and fungi under study. Moreover NFOCP particles did not show any significant activity for both bacteria's and fungi. Further, antimicrobial activity of nickel ferrite nanoparticles were studied even for different concentration to obtain the minimum inhibition concentration (MIC).

Routing Service Quality—Local Driver Behavior Versus Routing Services

DEFF Research Database (Denmark)

Ceikute, Vaida; Jensen, Christian S.

2013-01-01

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...... popularity, which are enabled by common driving behaviors found in available trajectory data. The ability to evaluate the quality of routing services enables service providers to improve the quality of their services and enables users to identify the services that best serve their needs. The paper covers......Mobile location-based services is a very successful class of services that are being used frequently by users with GPS-enabled mobile devices such as smartphones. This paper presents a study of how to exploit GPS trajectory data, which is available in increasing volumes, for the assessment...

Indoor Semantic Modelling for Routing: The Two-Level Routing Approach for Indoor Navigation

Directory of Open Access Journals (Sweden)

Liu Liu

2017-11-01

Full Text Available Humans perform many activities indoors and they show a growing need for indoor navigation, especially in unfamiliar buildings such as airports, museums and hospitals. Complexity of such buildings poses many challenges for building managers and visitors. Indoor navigation services play an important role in supporting these indoor activities. Indoor navigation covers extensive topics such as: 1 indoor positioning and localization; 2 indoor space representation for navigation model generation; 3 indoor routing computation; 4 human wayfinding behaviours; and 5 indoor guidance (e.g., textual directories. So far, a large number of studies of pedestrian indoor navigation have presented diverse navigation models and routing algorithms/methods. However, the major challenge is rarely referred to: how to represent the complex indoor environment for pedestrians and conduct routing according to the different roles and sizes of users. Such complex buildings contain irregular shapes, large open spaces, complicated obstacles and different types of passages. A navigation model can be very complicated if the indoors are accurately represented. Although most research demonstrates feasible indoor navigation models and related routing methods in regular buildings, the focus is still on a general navigation model for pedestrians who are simplified as circles. In fact, pedestrians represent different sizes, motion abilities and preferences (e.g., described in user profiles, which should be reflected in navigation models and be considered for indoor routing (e.g., relevant Spaces of Interest and Points of Interest. In order to address this challenge, this thesis proposes an innovative indoor modelling and routing approach – two-level routing. It specially targets the case of routing in complex buildings for distinct users. The conceptual (first level uses general free indoor spaces: this is represented by the logical network whose nodes represent the spaces and edges

Aircraft route forecasting under adverse weather conditions

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Thomas Hauf

2017-04-01

Full Text Available In this paper storm nowcasts in the terminal manoeuvring area (TMA of Hong Kong International Airport are used to forecast deviation routes through a field of storms for arriving and departing aircraft. Storms were observed and nowcast by the nowcast system SWIRLS from the Hong Kong Observatory. Storms were considered as no-go zones for aircraft and deviation routes were determined with the DIVSIM software package. Two days (21 and 22 May 2011 with 22 actual flown routes were investigated. Flights were simulated with a nowcast issued at the time an aircraft entered the TMA or departed from the airport. These flights were compared with a posteriori simulations, in which all storm fields were known and circumnavigated. Both types of simulated routes were then compared with the actual flown routes. The qualitative comparison of the various routes revealed generally good agreement. Larger differences were found in more complex situations with many active storms in the TMA. Route differences resulted primarily from air traffic control measures imposed such as holdings, slow-downs and shortcuts, causing the largest differences between the estimated and actual landing time. Route differences could be enhanced as aircraft might be forced to circumnavigate a storm ahead in a different sense. The use of route forecasts to assist controllers coordinating flights in a complex moving storm field is discussed. The study emphasises the important application of storm nowcasts in aviation meteorology.

Phosphate Activation via Reduced Oxidation State Phosphorus (P. Mild Routes to Condensed-P Energy Currency Molecules

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Claire R. Cousins

2013-07-01

Full Text Available The emergence of mechanisms for phosphorylating organic and inorganic molecules is a key step en route to the earliest living systems. At the heart of all contemporary biochemical systems reside reactive phosphorus (P molecules (such as adenosine triphosphate, ATP as energy currency molecules to drive endergonic metabolic processes and it has been proposed that a predecessor of such molecules could have been pyrophosphate [P2O74−; PPi(V]. Arguably the most geologically plausible route to PPi(V is dehydration of orthophosphate, Pi(V, normally a highly endergonic process in the absence of mechanisms for activating Pi(V. One possible solution to this problem recognizes the presence of reactive-P containing mineral phases, such as schreibersite [(Fe,Ni3P] within meteorites whose abundance on the early Earth would likely have been significant during a putative Hadean-Archean heavy bombardment. Here, we propose that the reduced oxidation state P-oxyacid, H-phosphite [HPO32−; Pi(III] could have activated Pi(V towards condensation via the intermediacy of the condensed oxyacid pyrophosphite [H2P2O52−; PPi(III]. We provide geologically plausible provenance for PPi(III along with evidence of its ability to activate Pi(V towards PPi(V formation under mild conditions (80 °C in water.

Network harness: bundles of routes in public transport networks

Science.gov (United States)

Berche, B.; von Ferber, C.; Holovatch, T.

2009-12-01

Public transport routes sharing the same grid of streets and tracks are often found to proceed in parallel along shorter or longer sequences of stations. Similar phenomena are observed in other networks built with space consuming links such as cables, vessels, pipes, neurons, etc. In the case of public transport networks (PTNs) this behavior may be easily worked out on the basis of sequences of stations serviced by each route. To quantify this behavior we use the recently introduced notion of network harness. It is described by the harness distribution P(r, s): the number of sequences of s consecutive stations that are serviced by r parallel routes. For certain PTNs that we have analyzed we observe that the harness distribution may be described by power laws. These power laws indicate a certain level of organization and planning which may be driven by the need to minimize the costs of infrastructure and secondly by the fact that points of interest tend to be clustered in certain locations of a city. This effect may be seen as a result of the strong interdependence of the evolutions of both the city and its PTN. To further investigate the significance of the empirical results we have studied one- and two-dimensional models of randomly placed routes modeled by different types of walks. While in one dimension an analytic treatment was successful, the two dimensional case was studied by simulations showing that the empirical results for real PTNs deviate significantly from those expected for randomly placed routes.

How well do modelled routes to school record the environments children are exposed to?: a cross-sectional comparison of GIS-modelled and GPS-measured routes to school

Science.gov (United States)

2014-01-01

Background The school journey may make an important contribution to children’s physical activity and provide exposure to food and physical activity environments. Typically, Geographic Information Systems (GIS) have been used to model assumed routes to school in studies, but these may differ from those actually chosen. We aimed to identify the characteristics of children and their environments that make the modelled route more or less representative of that actually taken. We compared modelled GIS routes and actual Global Positioning Systems (GPS) measured routes in a free-living sample of children using varying travel modes. Methods Participants were 175 13-14 yr old children taking part in the Sport, Physical activity and Eating behaviour: Environmental Determinants in Young people (SPEEDY) study who wore GPS units for up to 7 days. Actual routes to/from school were extracted from GPS data, and shortest routes between home and school along a road network were modelled in a GIS. Differences between them were assessed according to length, percentage overlap, and food outlet exposure using multilevel regression models. Results GIS routes underestimated route length by 21.0% overall, ranging from 6.1% among walkers to 23.2% for bus users. Among pedestrians food outlet exposure was overestimated by GIS routes by 25.4%. Certain characteristics of children and their neighbourhoods that improved the concordance between GIS and GPS route length and overlap were identified. Living in a village raised the odds of increased differences in length (odds ratio (OR) 3.36 (1.32-8.58)), while attending a more urban school raised the odds of increased percentage overlap (OR 3.98 (1.49-10.63)). However none were found for food outlet exposure. Journeys home from school increased the difference between GIS and GPS routes in terms of food outlet exposure, and this measure showed considerable within-person variation. Conclusions GIS modelled routes between home and school were not

State alternative route designations

International Nuclear Information System (INIS)

1989-07-01

Pursuant to the Hazardous Materials Transportation Act (HMTA), the Department of Transportation (DOT) has promulgated a comprehensive set of regulations regarding the highway transportation of high-level radioactive materials. These regulations, under HM-164 and HM-164A, establish interstate highways as the preferred routes for the transportation of radioactive materials within and through the states. The regulations also provide a methodology by which a state may select alternative routes. First,the state must establish a ''state routing agency,'' defined as an entity authorized to use the state legal process to impose routing requirements on carriers of radioactive material (49 CFR 171.8). Once identified, the state routing agency must select routes in accordance with Large Quantity Shipments of Radioactive Materials or an equivalent routing analysis. Adjoining states and localities should be consulted on the impact of proposed alternative routes as a prerequisite of final route selection. Lastly, the states must provide written notice of DOT of any alternative route designation before the routes are deemed effective

Low Carbon Footprint Routes for Bird Watching

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Wei-Ta Fang

2015-03-01

Full Text Available Bird watching is one of many recreational activities popular in ecotourism. Its popularity, therefore, prompts the need for studies on energy conservation. One such environmentally friendly approach toward minimizing bird watching’s ecological impact is ensuring a reduced carbon footprint by using an economic travel itinerary comprising a series of connected routes between tourist attractions that minimizes transit time. This study used a travel-route planning approach using geographic information systems to detect the shortest path, thereby solving the problems associated with time-consuming transport. Based on the results of road network analyses, optimal travel-route planning can be determined. These methods include simulated annealing (SA and genetic algorithms (GA. We applied two algorithms in our simulation research to detect which one is an appropriate algorithm for running carbon-routing algorithms at the regional scale. SA, which is superior to GA, is considered an excellent approach to search for the optimal path to reduce carbon dioxide and high gasoline fees, thereby controlling travel time by using the shortest travel routes.

A Shear Strain Route Dependency of Martensite Formation in 316L Stainless Steel.

Science.gov (United States)

Kang, Suk Hoon; Kim, Tae Kyu; Jang, Jinsung; Oh, Kyu Hwan

2015-06-01

In this study, the effect of simple shearing on microstructure evolution and mechanical properties of 316L austenitic stainless steel were investigated. Two different shear strain routes were obtained by twisting cylindrical specimens in the forward and backward directions. The strain-induced martensite phase was effectively obtained by alteration of the routes. Formation of the martensite phase clearly resulted in significant hardening of the steel. Grain-size reduction and strain-induced martensitic transformation within the deformed structures of the strained specimens were characterized by scanning electron microscopy - electron back-scattered diffraction, X-ray diffraction, and the TEM-ASTAR (transmission electron microscopy - analytical scanning transmission atomic resolution, automatic crystal orientation/phase mapping for TEM) system. Significant numbers of twin networks were formed by alteration of the shear strain routes, and the martensite phases were nucleated at the twin interfaces.

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...

Converging migration routes of Eurasian hobbies Falco subbuteo crossing the African equatorial rain forest.

Science.gov (United States)

Strandberg, Roine; Klaassen, Raymond H G; Hake, Mikael; Olofsson, Patrik; Alerstam, Thomas

2009-02-22

Autumn migration of adult Eurasian hobbies Falco subbuteo from Europe to southern Africa was recorded by satellite telemetry and observed routes were compared with randomly simulated routes. Two non-random features of observed routes were revealed: (i) shifts to more westerly longitudes than straight paths to destinations and (ii) strong route convergence towards a restricted area close to the equator (1 degree S, 15 degrees E). The birds migrated south or southwest to approximately 10 degrees N, where they changed to south-easterly courses. The maximal spread between routes at 10 degrees N (2134 km) rapidly decreased to a minimum (67 km) close to the equator. We found a striking relationship between the route convergence and the distribution of continuous rainforest, suggesting that hobbies minimize flight distance across the forest, concentrating in a corridor where habitat may be more suitable for travelling and foraging. With rainforest forming a possible ecological barrier, many migrants may cross the equator either at 15 degrees E, similar to the hobbies, or at 30-40 degrees E, east of the rainforest where large-scale migration is well documented. Much remains to be understood about the role of the rainforest for the evolution and future of the trans-equatorial Palaearctic-African bird migration systems.

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.

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...

Cooperative Optimization QoS Cloud Routing Protocol Based on Bacterial Opportunistic Foraging and Chemotaxis Perception for Mobile Internet

Directory of Open Access Journals (Sweden)

Shujuan Wang

2015-01-01

Full Text Available In order to strengthen the mobile Internet mobility management and cloud platform resources utilization, optimizing the cloud routing efficiency is established, based on opportunistic bacterial foraging bionics, and puts forward a chemotaxis perception of collaborative optimization QoS (Quality of Services cloud routing mechanism. The cloud routing mechanism is based on bacterial opportunity to feed and bacterial motility and to establish the data transmission and forwarding of the bacterial population behavior characteristics. This mechanism is based on the characteristics of drug resistance of bacteria and the structure of the field, and through many iterations of the individual behavior and population behavior the bacteria can be spread to the food gathering area with a certain probability. Finally, QoS cloud routing path would be selected and optimized based on bacterial bionic optimization and hedge mapping relationship between mobile Internet node and bacterial population evolution iterations. Experimental results show that, compared with the standard dynamic routing schemes, the proposed scheme has shorter transmission delay, lower packet error ratio, QoS cloud routing loading, and QoS cloud route request overhead.

Secure Multicast Routing Algorithm for Wireless Mesh Networks

Directory of Open Access Journals (Sweden)

Rakesh Matam

2016-01-01

Full Text Available Multicast is an indispensable communication technique in wireless mesh network (WMN. Many applications in WMN including multicast TV, audio and video conferencing, and multiplayer social gaming use multicast transmission. On the other hand, security in multicast transmissions is crucial, without which the network services are significantly disrupted. Existing secure routing protocols that address different active attacks are still vulnerable due to subtle nature of flaws in protocol design. Moreover, existing secure routing protocols assume that adversarial nodes cannot share an out-of-band communication channel which rules out the possibility of wormhole attack. In this paper, we propose SEMRAW (SEcure Multicast Routing Algorithm for Wireless mesh network that is resistant against all known active threats including wormhole attack. SEMRAW employs digital signatures to prevent a malicious node from gaining illegitimate access to the message contents. Security of SEMRAW is evaluated using the simulation paradigm approach.

Planning routes around the world: International evidence for southern route preferences

NARCIS (Netherlands)

Brunyé, Tad T.; Andonova, Elena; Meneghetti, Chiara; Noordzij, Matthijs Leendert; Pazzaglia, Francesca; Wienemann, Rasmus; Mahoney, Caroline R.; Taylor, Holly A.

2012-01-01

Three studies test whether the southern route preference, which describes the tendency for route planners to disproportionately select south- rather than north-going routes, can be attributed to regional elevation patterns; specifically, we ask whether this effect replicates in three topographically

A Day-to-Day Route Choice Model Based on Reinforcement Learning

Directory of Open Access Journals (Sweden)

Fangfang Wei

2014-01-01

Full Text Available Day-to-day traffic dynamics are generated by individual traveler’s route choice and route adjustment behaviors, which are appropriate to be researched by using agent-based model and learning theory. In this paper, we propose a day-to-day route choice model based on reinforcement learning and multiagent simulation. Travelers’ memory, learning rate, and experience cognition are taken into account. Then the model is verified and analyzed. Results show that the network flow can converge to user equilibrium (UE if travelers can remember all the travel time they have experienced, but which is not necessarily the case under limited memory; learning rate can strengthen the flow fluctuation, but memory leads to the contrary side; moreover, high learning rate results in the cyclical oscillation during the process of flow evolution. Finally, both the scenarios of link capacity degradation and random link capacity are used to illustrate the model’s applications. Analyses and applications of our model demonstrate the model is reasonable and useful for studying the day-to-day traffic dynamics.

Defect evolution and dopant activation in laser annealed Si and Ge

DEFF Research Database (Denmark)

Cristiano, F.; Shayesteh, M.; Duffy, R.

2016-01-01

Defect evolution and dopant activation are intimately related to the use of ion implantation and annealing, traditionally used to dope semiconductors during device fabrication. Ultra-fast laser thermal annealing (LTA) is one of the most promising solutions for the achievement of abrupt and highly...... doped junctions. In this paper, we report some recent investigations focused on this annealing method, with particular emphasis on the investigation of the formation and evolution of implant/anneal induced defects and their impact on dopant activation. In the case of laser annealed Silicon, we show...

Wine routes as an element of the regional development of borderline regions

Directory of Open Access Journals (Sweden)

Vladimir Drozg

1993-12-01

Full Text Available The article examines the role of winw routes in promoting the development of wine-growing regions. It focuses both on the criteria for tracing wine routes (landscape value of a region, distribution of tourist supply settlements and events, natural and cultural monuments, existing road netivorks and transport accessibility, supplemenlary activities along the wine routes and on the impact that wine exert on the landscape/region (an increased income of individual households, better infrastructure equipment, recuttivation ol desert land lots, decreasing depopulalion and development of supplementary activities. The wine route through the Svečinske gorice region is presented as an example of countryside regulation.

Galaxy mergers and active nuclei. II. Cosmological evolution

International Nuclear Information System (INIS)

Roos, N.

1985-01-01

Galaxy mergers may produce active galactic nuclei (AGNs) by repopulating stellar loss-cone orbits around a central black hole. In the companion paper we derived a local bolometric luminosity function of AGNs based on this process. In this paper we interpret the observed cosmological evolution of the luminosity function of AGNs as due to evolution of the merging rate among galaxies after their formation at a redshift of approx.3. An important difference between our model and previous (empirical) models is that the evolution depends on galactic (stellar) luminosity instead of central nonthermal luminosity. The radio counts at 1.4 GHz and optical counts are reproduced by the model if the merging rate of the galaxies at the bright end of the galaxy luminosity function evolves considerably faster than the merging rate of the smaller galaxies. The theoretical and observed luminosity functions at high redshift have similar characteristics: (i) at high luminosity the evolution is best described by luminosity evolution, and (2) the luminosity function has a maximum at approx.10 3 Gpc -3 , which is the space density of the most massive galaxies. A large fraction of these galaxies are presumably formed in the precursors of rich clusters. Their merger rate is high initially and declines rapidly on a time scale of a few billion years. If the initial density fluctuation spectrum for protoclusters of mass M/sub cl/ has the form deltarho/rhoproportionalM/sup( -1+n//3)/2/sub cl/, then the steep evolution of the most luminous galaxies suggests nroughly-equal-1.3 at a redshift of approx.3, which is consistent with the observed clustering of galaxies

Electrochemical Sensing, Photocatalytic and Biological Activities of ZnO Nanoparticles: Synthesis via Green Chemistry Route

Science.gov (United States)

Yadav, L. S. Reddy; Archana, B.; Lingaraju, K.; Kavitha, C.; Suresh, D.; Nagabhushana, H.; Nagaraju, G.

2016-05-01

In this paper, we have successfully synthesized ZnO nanoparticles (Nps) via solution combustion method using sugarcane juice as the novel fuel. The structure and morphology of the synthesized ZnO Nps have been analyzed using various analytical tools. The synthesized ZnO Nps exhibit excellent photocatalytic activity for the degradation of methylene blue dye, indicating that the ZnO Nps are potential photocatalytic semiconductor materials. The synthesized ZnO Nps also show good electrochemical sensing of dopamine. ZnO Nps exhibit significant bactericidal activity against Klebsiella aerogenes, Pseudomonas aeruginosa, Eschesichia coli and Staphylococcus aureus using agar well diffusion method. Furthermore, the ZnO Nps show good antioxidant activity by potentially scavenging 1-diphenyl-2-picrylhydrazyl (DPPH) radicals. The above studies clearly demonstrate versatile applications of ZnO synthesized by simple eco-friendly route.

Transportation routing analysis geographic information system -- TRAGIS, a multimodal transportation routing tool

International Nuclear Information System (INIS)

Johnson, P.E.

1995-01-01

Over 15 years ago, Oak Ridge National Laboratory (ORNL) developed two transportation routing models: HIGHWAY, which predicts truck transportation routes, and INTERLINE, which predicts rail transportation routes. Subsequent modifications have been made to enhance each of these models. Some of these changes include population density information for routes, HM-164 routing regulations for highway route controlled quantities of radioactive materials (RAM) truck shipments, and inclusion of waterway routing into INTERLINE. The AIRPORT model, developed 2 years after the HIGHWAY and INTERLINE models, serves as an emergency response tool. This model identifies the nearest airports from a designated location. Currently, the AIRPORT model is inactive. The Transportation Management Division of the US Department of Energy held a Baseline Requirements Assessment Session on the HIGHWAY, INTERLINE, and AIRPORT models in April 1994 to bring together many users of these models and other experts in the transportation routing field to discuss these models and to decide on the capabilities that needed to be added. Of the many needs discussed, the primary one was to have the network databases within a geographic information system (GIS). As a result of the Baseline Requirements Session, the development of a new GIS model has been initiated. This paper will discuss the development of the new Transportation Routing Analysis GIS (TRAGIS) model at ORNL

VINE ROUTES IN BULGARIA

Directory of Open Access Journals (Sweden)

Lyuben Hristov

2015-03-01

Full Text Available The article deals with a scheme for the modern vine route in Bulgaria. Five basic vine routes and one international, between Bulgaria, Macedonia and Greece are defined. All routes consider characteristic varieties of grapes and kinds of vine products. Vine tourist products combined with visits of important natural and anthropological object are in the bases of the defined routes. The described routes are an important contribution to development of alternative tourist products in the country.

Robust against route failure using power proficient reliable routing in MANET

Directory of Open Access Journals (Sweden)

M. Malathi

2018-03-01

Full Text Available The aim of this paper was to propose a novel routing protocol for Mobile Adhoc Network communication which reduces the route failure during transmission. The proposed routing protocol uses 3 salient parameters to discover the path which ensure the reliable communication. The quality of the channel, link quality and energy level of the node are the major reasons for unintentional node failure in mobile Adhoc network. So the proposed routing protocol considers these three parameters to select the best forwarder node in the path. The reliable data communication is achieved by transmitting data via path selected by the proposed routing scheme has been proven using network simulator (NS2. Keywords: Channel quality, Link quality, Mobile Adhoc Network (MANET, Residual energy

Hormonally active phytochemicals and vertebrate evolution.

Science.gov (United States)

Lambert, Max R; Edwards, Thea M

2017-06-01

Living plants produce a diversity of chemicals that share structural and functional properties with vertebrate hormones. Wildlife species interact with these chemicals either through consumption of plant materials or aquatic exposure. Accumulating evidence shows that exposure to these hormonally active phytochemicals (HAPs) often has consequences for behavior, physiology, and fecundity. These fitness effects suggest there is potential for an evolutionary response by vertebrates to HAPs. Here, we explore the toxicological HAP-vertebrate relationship in an evolutionary framework and discuss the potential for vertebrates to adapt to or even co-opt the effects of plant-derived chemicals that influence fitness. We lay out several hypotheses about HAPs and provide a path forward to test whether plant-derived chemicals influence vertebrate reproduction and evolution. Studies of phytochemicals with direct impacts on vertebrate reproduction provide an obvious and compelling system for studying evolutionary toxicology. Furthermore, an understanding of whether animal populations evolve in response to HAPs could provide insightful context for the study of rapid evolution and how animals cope with chemical agents in the environment.

Genomic analyses of breast cancer progression reveal distinct routes of metastasis emergence

DEFF Research Database (Denmark)

Krøigård, Anne Bruun; Larsen, Martin Jakob; Brasch-Andersen, Charlotte

2017-01-01

receptor (ER)-positive breast cancer. Our data provide support for both linear and parallel progression towards metastasis. We report for the first time evidence of metastasis-to-metastasis seeding in breast cancer. Our results point to three distinct routes of metastasis emergence. This may have profound...... clinical implications and provides substantial novel molecular insights into the timing and mutational evolution of breast cancer metastasis....

Composition and microstructure of zirconium and hafnium germanates obtained by different chemical routes

International Nuclear Information System (INIS)

Utkin, A.V.; Prokip, V.E.; Baklanova, N.I.

2014-01-01

The phase composition and morphology of zirconium and hafnium germanates synthesized by ceramic and co-precipitation routes were studied. The products were characterized using high-temperature X-ray diffraction analysis (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and thermal (TG/DTA) analysis. To investigate the phase composition and stoichiometry of compounds the unit cell parameters were refined by full-profile Rietveld XRD analysis. The morphology of products and its evolution during high-temperature treatment was examined by SEM analysis. It was stated that there is the strong dependence of the phase composition and morphology of products on the preparation route. The ceramic route requires a multi-stage high-temperature treatment to obtain zirconium and hafnium germanates of 95% purity or more. Also, there are strong diffusion limitations to obtain hafnium germanate Hf 3 GeO 8 by ceramic route. On the contrary, the co-precipitation route leads to the formation of nanocrystalline single phase germanates of stoichiometric composition at a relatively low temperatures (less than 1000 °C). The results of quantitative XRD analysis showed the hafnium germanates are stoichiometric compounds in contrast to zirconium germanates that form a set of solid solutions. This distinction may be related to the difference in the ion radii of Zr and Hf. - Graphical abstract: The phase composition and morphology of zirconium and hafnium germanates synthesized by ceramic and co-precipitation routes were studied. It was stated that there is the strong dependence of the phase composition and morphology of products on the preparation route. Display Omitted - Highlights: • Zr and Hf germanates were synthesized by ceramic and co-precipitation routes. • The morphology of products depends on the synthesis parameters. • Zirconium germanates forms a set of solid solutions. • Hafnium germanates are stoichiometric compounds

An Immune Cooperative Particle Swarm Optimization Algorithm for Fault-Tolerant Routing Optimization in Heterogeneous Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Yifan Hu

2012-01-01

Full Text Available The fault-tolerant routing problem is important consideration in the design of heterogeneous wireless sensor networks (H-WSNs applications, and has recently been attracting growing research interests. In order to maintain k disjoint communication paths from source sensors to the macronodes, we present a hybrid routing scheme and model, in which multiple paths are calculated and maintained in advance, and alternate paths are created once the previous routing is broken. Then, we propose an immune cooperative particle swarm optimization algorithm (ICPSOA in the model to provide the fast routing recovery and reconstruct the network topology for path failure in H-WSNs. In the ICPSOA, mutation direction of the particle is determined by multi-swarm evolution equation, and its diversity is improved by immune mechanism, which can enhance the capacity of global search and improve the converging rate of the algorithm. Then we validate this theoretical model with simulation results. The results indicate that the ICPSOA-based fault-tolerant routing protocol outperforms several other protocols due to its capability of fast routing recovery mechanism, reliable communications, and prolonging the lifetime of WSNs.

Sustainable bio kerosene: Process routes and industrial demonstration activities in aviation biofuels

International Nuclear Information System (INIS)

Chiaramonti, David; Prussi, Matteo; Buffi, Marco; Tacconi, Daniela

2014-01-01

Highlights: • Routes to aviation biofuels are examined, focusing on drop-in biofuels, capable of high blend levels with fossil kerosene. • Industrial demonstration activities are reported. • Used cooking oil is considered as alternative sustainable biomass feedstock for paraffinic fuel production. - Abstract: Alternative fuels are expected to play a major role in EU in the coming years due European Directives on the promotion of renewable energies and reduction of greenhouse gas emissions in transports. However, while in road transports a variety of possible renewable fuels (mainly biofuels, but also electricity) can be considered, in aviation only high quality paraffinic biofuels can be adopted. This means that biomass must be converted through advanced processes into pure hydrocarbon fuels, fully compatible with the existing systems. The aviation sector is responsible for the 2% of the world anthropogenic CO 2 emissions and the 10% of the fuel consumption: airlines’ costs for fuel reach 30% of operating costs. In addition, the aviation traffic is expected to double within 15 years from 2012, while fuel consumption and CO 2 emissions should double in 25 years. Thus, more than 2 billion people and 40 Mt of good/cargo will have to be moved every year. In this context, the EU Flightpath set a target of 2 Mt per year for aviation alternative fuel by 2020 (i.e. 4% of annual fuel consumption). New processes towards bio-hydrocarbons are being developed, demonstrated and soon industrialized. The present work explores the possible routes from biomass feedstock to sustainable paraffinic fuels, either through bio or thermo-chemical processes, as well as discusses those more mature, focusing on industrial demonstration initiatives. In fact, while the number of possible options towards paraffinic biofuel production is very large, and covers both thermochemical and biochemical routes, as well as hybrid one, only two pathways are today ready for testing a significant

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

Understanding the main route of drug entry in adult Fasciola hepatica: Further insights into closantel pharmacological activity.

Science.gov (United States)

Ceballos, L; Canton, C; Cadenazzi, G; Larsen, K; Virkel, G; Moreno, L; Fairweather, I; Lanusse, C; Alvarez, L

2017-10-01

Closantel (CLS) is highly effective against adult liver flukes after its oral or subcutaneous (sc) administration in ruminants. Trans-tegumental diffusion and oral ingestion are the two potential routes available for the entry of drugs into Fasciola hepatica. The work reported here contributes to improve the understanding of CLS pharmacology. The main goals of were: I) to determine the pattern of in vivo CLS accumulation into adult F. hepatica and relevant tissues in CLS-treated sheep; II) to investigate the influence of the physicochemical composition of the incubation medium on the CLS diffusion process into adult F. hepatica; III) to assess the ovicidal activity of CLS against F. hepatica eggs; and IV) to investigate the in vivo effect of CLS treatment on glutathione S-transferases activity in adult liver flukes exposed to CLS. Fourteen healthy sheep were each orally infected with 75 F. hepatica metacercariae. Sixteen (16) weeks after infection, animals were treated with CLS by oral (n = 6, 10 mg/kg) or sub-cutaneous (sc) (n = 6, 5 mg/kg) route. At 12, 24 and 36 h post-treatment, animals were sacrificed (n = 2) and samples of blood, bile and adult F. hepatica were collected. In addition, flukes recovered from non-treated sheep (n = 2) were ex vivo incubated (60 min) in the presence of CLS in either RPMI or bile as incubation medium. CLS concentration was measured by HPLC. The ovicidal activity of CLS was investigated using eggs obtained from the bile of untreated sheep. Finally, glutathione S-transferase activity in F. hepatica recovered from untreated and CLS-treated sheep was assessed. In the in vivo studies, the highest CLS concentrations were measured in plasma and adult liver flukes. A positive correlation was observed between CLS concentration in plasma and in F. hepatica. Results obtained in the current work indicate that the in vivo accumulation of CLS into adult liver flukes occurs mainly by the oral route. After ex

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...

Exploring bikeability in a metropolitan setting: stimulating and hindering factors in commuting route environments

Directory of Open Access Journals (Sweden)

Wahlgren Lina

2012-03-01

Full Text Available Abstract Background Route environments may influence people's active commuting positively and thereby contribute to public health. Assessments of route environments are, however, needed in order to better understand the possible relationship between active commuting and the route environment. The aim of this study was, therefore, to assess the potential associations between perceptions of whether the route environment on the whole hinders or stimulates bicycle commuting and perceptions of environmental factors. Methods The Active Commuting Route Environment Scale (ACRES was used for the assessment of bicycle commuters' perceptions of their route environments in the inner urban parts of Greater Stockholm, Sweden. Bicycle commuters (n = 827 were recruited by advertisements in newspapers. Simultaneous multiple regression analyses were used to assess the relation between predictor variables (such as levels of exhaust fumes, noise, traffic speed, traffic congestion and greenery and the outcome variable (hindering - stimulating route environments. Two models were run, (Model 1 without and (Model 2 with the item traffic: unsafe or safe included as a predictor. Results Overall, about 40% of the variance of hindering - stimulating route environments was explained by the environmental predictors in our models (Model 1, R2 = 0.415, and Model 2, R 2= 0.435. The regression equation for Model 1 was: y = 8.53 + 0.33 ugly or beautiful + 0.14 greenery + (-0.14 course of the route + (-0.13 exhaust fumes + (-0.09 congestion: all types of vehicles (p ≤ 0.019. The regression equation for Model 2 was y = 6.55 + 0.31 ugly or beautiful + 0.16 traffic: unsafe or safe + (-0.13 exhaust fumes + 0.12 greenery + (-0.12 course of the route (p ≤ 0.001. Conclusions The main results indicate that beautiful, green and safe route environments seem to be, independently of each other, stimulating factors for bicycle commuting in inner urban areas. On the other hand, exhaust

Metabolic profiling of alternative NAD biosynthetic routes in mouse tissues.

Directory of Open Access Journals (Sweden)

Valerio Mori

Full Text Available NAD plays essential redox and non-redox roles in cell biology. In mammals, its de novo and recycling biosynthetic pathways encompass two independent branches, the "amidated" and "deamidated" routes. Here we focused on the indispensable enzymes gating these two routes, i.e. nicotinamide mononucleotide adenylyltransferase (NMNAT, which in mammals comprises three distinct isozymes, and NAD synthetase (NADS. First, we measured the in vitro activity of the enzymes, and the levels of all their substrates and products in a number of tissues from the C57BL/6 mouse. Second, from these data, we derived in vivo estimates of enzymes'rates and quantitative contributions to NAD homeostasis. The NMNAT activity, mainly represented by nuclear NMNAT1, appears to be high and nonrate-limiting in all examined tissues, except in blood. The NADS activity, however, appears rate-limiting in lung and skeletal muscle, where its undetectable levels parallel a relative accumulation of the enzyme's substrate NaAD (nicotinic acid adenine dinucleotide. In all tissues, the amidated NAD route was predominant, displaying highest rates in liver and kidney, and lowest in blood. In contrast, the minor deamidated route showed higher relative proportions in blood and small intestine, and higher absolute values in liver and small intestine. Such results provide the first comprehensive picture of the balance of the two alternative NAD biosynthetic routes in different mammalian tissues under physiological conditions. This fills a gap in the current knowledge of NAD biosynthesis, and provides a crucial information for the study of NAD metabolism and its role in disease.

A Chemical Route to Activation of Open Metal Sites in the Copper-Based Metal-Organic Framework Materials HKUST-1 and Cu-MOF-2.

Science.gov (United States)

Kim, Hong Ki; Yun, Won Seok; Kim, Min-Bum; Kim, Jeung Yoon; Bae, Youn-Sang; Lee, JaeDong; Jeong, Nak Cheon

2015-08-12

Open coordination sites (OCSs) in metal-organic frameworks (MOFs) often function as key factors in the potential applications of MOFs, such as gas separation, gas sorption, and catalysis. For these applications, the activation process to remove the solvent molecules coordinated at the OCSs is an essential step that must be performed prior to use of the MOFs. To date, the thermal method performed by applying heat and vacuum has been the only method for such activation. In this report, we demonstrate that methylene chloride (MC) itself can perform the activation role: this process can serve as an alternative "chemical route" for the activation that does not require applying heat. To the best of our knowledge, no previous study has demonstrated this function of MC, although MC has been popularly used in the pretreatment step prior to the thermal activation process. On the basis of a Raman study, we propose a plausible mechanism for the chemical activation, in which the function of MC is possibly due to its coordination with the Cu(2+) center and subsequent spontaneous decoordination. Using HKUST-1 film, we further demonstrate that this chemical activation route is highly suitable for activating large-area MOF films.

Evaluation of RPL-compliant routing solutions in real-life WSNs

Directory of Open Access Journals (Sweden)

Zahariadis Theodore

2016-01-01

Full Text Available Wireless Sensor Networks (WSN applications continue to expand and already cover almost all our daily activities improving from security and environmental efficiency to gaming experience. The diverse applications running on top of WSNs have led to the design of an immense number of routing protocols. Few years ago, the IETF standardized the IPv6 routing protocol for low-power and lossy networks (RPL which is based on routing metrics to build communication paths between a source and the destination node. While significant efforts have focused on the design of routing metrics that satisfy the various applications, limited work has been reported on validating their performance using real-life motes. In this paper, we focus on validating the simulation results (obtained through the JSim simulator using TelosB motes for a set of routing metrics that have been proposed in our previous articles.

Evolution of weighted complex bus transit networks with flow

Science.gov (United States)

Huang, Ailing; Xiong, Jie; Shen, Jinsheng; Guan, Wei

2016-02-01

Study on the intrinsic properties and evolutional mechanism of urban public transit networks (PTNs) has great significance for transit planning and control, particularly considering passengers’ dynamic behaviors. This paper presents an empirical analysis for exploring the complex properties of Beijing’s weighted bus transit network (BTN) based on passenger flow in L-space, and proposes a bi-level evolution model to simulate the development of transit routes from the view of complex network. The model is an iterative process that is driven by passengers’ travel demands and dual-controlled interest mechanism, which is composed of passengers’ spatio-temporal requirements and cost constraint of transit agencies. Also, the flow’s dynamic behaviors, including the evolutions of travel demand, sectional flow attracted by a new link and flow perturbation triggered in nearby routes, are taken into consideration in the evolutional process. We present the numerical experiment to validate the model, where the main parameters are estimated by using distribution functions that are deduced from real-world data. The results obtained have proven that our model can generate a BTN with complex properties, such as the scale-free behavior or small-world phenomenon, which shows an agreement with our empirical results. Our study’s results can be exploited to optimize the real BTN’s structure and improve the network’s robustness.

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

Evolution of active region loop plasma

International Nuclear Information System (INIS)

Krall, K.R.; Antiochos, S.K.

1980-01-01

We investigate numerically the adjustment of coronal active-region loops to changes in their heating rate. The one-dimensional hydrodynamic equations are solved subject to boundary conditions in which heat flux-induced mass exchange between coronal and chromospheric components is allowed. The calculated evolution of physical parameters suggests that (1) mass supplied during chromospheric evaporation is much more effective in moderating coronal temperature excursions than when downward heat flux if dissipated by a static chromosphere, and (2) the method by which rhe chromosphere responds to changing coronal conditions can significantly influence coronal readjustment time scales. Observations are cited which illustrate the range of possible fluctuations in the heating rates

Commercial vehicle route tracking using video detection.

Science.gov (United States)

2010-10-31

Interstate commercial vehicle traffic is a major factor in the life of any road surface. The ability to track : these vehicles and their routes through the state can provide valuable information to planning : activities. We propose a method using vid...

Understanding individual routing behaviour.

Science.gov (United States)

Lima, Antonio; Stanojevic, Rade; Papagiannaki, Dina; Rodriguez, Pablo; González, Marta C

2016-03-01

Knowing how individuals move between places is fundamental to advance our understanding of human mobility (González et al. 2008 Nature 453, 779-782. (doi:10.1038/nature06958)), improve our urban infrastructure (Prato 2009 J. Choice Model. 2, 65-100. (doi:10.1016/S1755-5345(13)70005-8)) and drive the development of transportation systems. Current route-choice models that are used in transportation planning are based on the widely accepted assumption that people follow the minimum cost path (Wardrop 1952 Proc. Inst. Civ. Eng. 1, 325-362. (doi:10.1680/ipeds.1952.11362)), despite little empirical support. Fine-grained location traces collected by smart devices give us today an unprecedented opportunity to learn how citizens organize their travel plans into a set of routes, and how similar behaviour patterns emerge among distinct individual choices. Here we study 92 419 anonymized GPS trajectories describing the movement of personal cars over an 18-month period. We group user trips by origin-destination and we find that most drivers use a small number of routes for their routine journeys, and tend to have a preferred route for frequent trips. In contrast to the cost minimization assumption, we also find that a significant fraction of drivers' routes are not optimal. We present a spatial probability distribution that bounds the route selection space within an ellipse, having the origin and the destination as focal points, characterized by high eccentricity independent of the scale. While individual routing choices are not captured by path optimization, their spatial bounds are similar, even for trips performed by distinct individuals and at various scales. These basic discoveries can inform realistic route-choice models that are not based on optimization, having an impact on several applications, such as infrastructure planning, routing recommendation systems and new mobility solutions. © 2016 The Author(s).

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.

Some bifurcation routes to chaos of thermocapillary convection in two-dimensional liquid layers of finite extent

Energy Technology Data Exchange (ETDEWEB)

Li, K., E-mail: likai@imech.ac.cn [Key Laboratory of Microgravity, Chinese Academy of Sciences, Beijing 100190, China and National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, Beijing 100190 (China); Xun, B.; Hu, W. R. [Key Laboratory of Microgravity, Chinese Academy of Sciences, Beijing 100190, China and National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China)

2016-05-15

As a part of the preliminary studies for the future space experiment (Zona-K) in the Russian module of the International Space Station, some bifurcation routes to chaos of thermocapillary convection in two-dimensional liquid layers filled with 10 cSt silicone oil have been numerically studied in this paper. As the laterally applied temperature difference is raised, variations in the spatial structure and temporal evolution of the thermocapillary convection and a complex sequence of transitions are observed. The results show that the finite extent of the liquid layer significantly influences the tempo-spatial evolution of the thermocapillary convection. Moreover, the bifurcation route of the thermocapillary convection changes very sensitively by the aspect ratio of the liquid layer. With the increasing Reynolds number (applied temperature difference), the steady thermocapillary convection experiences two consecutive transitions from periodic oscillatory state to quasi-periodic oscillatory state with frequency-locking before emergence of chaotic convection in a liquid layer of aspect ratio 14.25, and the thermocapillary convection undergoes period-doubling cascades leading to chaotic convection in a liquid layer of aspect ratio 13.0.

Some bifurcation routes to chaos of thermocapillary convection in two-dimensional liquid layers of finite extent

International Nuclear Information System (INIS)

Li, K.; Xun, B.; Hu, W. R.

2016-01-01

As a part of the preliminary studies for the future space experiment (Zona-K) in the Russian module of the International Space Station, some bifurcation routes to chaos of thermocapillary convection in two-dimensional liquid layers filled with 10 cSt silicone oil have been numerically studied in this paper. As the laterally applied temperature difference is raised, variations in the spatial structure and temporal evolution of the thermocapillary convection and a complex sequence of transitions are observed. The results show that the finite extent of the liquid layer significantly influences the tempo-spatial evolution of the thermocapillary convection. Moreover, the bifurcation route of the thermocapillary convection changes very sensitively by the aspect ratio of the liquid layer. With the increasing Reynolds number (applied temperature difference), the steady thermocapillary convection experiences two consecutive transitions from periodic oscillatory state to quasi-periodic oscillatory state with frequency-locking before emergence of chaotic convection in a liquid layer of aspect ratio 14.25, and the thermocapillary convection undergoes period-doubling cascades leading to chaotic convection in a liquid layer of aspect ratio 13.0.

The vehicle routing problem latest advances and new challenges

CERN Document Server

Golden, Bruce L; Wasil, Edward A

2008-01-01

The Vehicle Routing Problem (VRP) has been an especially active and fertile area of research. Over the past five to seven years, there have been numerous technological advances and exciting challenges that are of considerable interest to students, teachers, and researchers. The Vehicle Routing Problem: Latest Advances and New Challenges will focus on a host of significant technical advances that have evolved over the past few years for modeling and solving vehicle routing problems and variants. New approaches for solving VRPs have been developed from important methodological advances. These developments have resulted in faster solution algorithms, more accurate techniques, and an improvement in the ability to solve large-scale, complex problems. The book will systematically examine these recent developments in the VRP and provide the following in a unified and carefully developed presentation: Present novel problems that have arisen in the vehicle routing domain and highlight new challenges for the field; Pre...

Enzyme activity measurement via spectral evolution profiling and PARAFAC

DEFF Research Database (Denmark)

Baum, Andreas; Meyer, Anne S.; Garcia, Javier Lopez

2013-01-01

The recent advances in multi-way analysis provide new solutions to traditional enzyme activity assessment. In the present study enzyme activity has been determined by monitoring spectral changes of substrates and products in real time. The method relies on measurement of distinct spectral...... fingerprints of the reaction mixture at specific time points during the course of the whole enzyme catalyzed reaction and employs multi-way analysis to detect the spectral changes. The methodology is demonstrated by spectral evolution profiling of Fourier Transform Infrared (FTIR) spectral fingerprints using...

SAFEBIKE: A Bike-sharing Route Recommender with Availability Prediction and Safe Routing

OpenAIRE

Zhong, Weisheng; Chen, Fanglan; Fu, Kaiqun; Lu, Chang-Tien

2017-01-01

This paper presents SAFEBIKE, a novel route recommendation system for bike-sharing service that utilizes station information to infer the number of available bikes in dock and recommend bike routes according to multiple factors such as distance and safety level. The system consists of a station level availability predictor that predicts bikes and docks amount at each station, and an efficient route recommendation service that considers safety and bike/dock availability factors. It targets use...

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.

Nanostructured palladium tailored via carbonyl chemical route towards oxygen reduction reaction

International Nuclear Information System (INIS)

Luo, Y.; Mora-Hernández, J.M.; Estudillo-Wong, L.A.; Arce-Estrada, E.M.; Alonso-Vante, N.

2015-01-01

Graphical Abstract: Mass-depending morphologies of nanostructured Palladium obtained via the carbonyl chemical route. Display Omitted -- Highlights: •Mass-depending morphology was observed in nanostructured palladium supported on carbon prepared by the carbonyl chemical route. •The Morphological effect of carbon supported Pd was investigated towards ORR. -- Abstract: Carbon supported palladium nanostructures were synthesized via the carbonyl chemical route. Compared with nanostructured platinum, prepared via carbonyl chemical route, Pd nanomaterials showed mass-loading morphology, whereas particle size and morphology of Pt nanostructures was constant. The oxygen reduction reaction (ORR) on nanostructured Pd, with different morphology in both acid and alkaline medium was investigated. A relationship, based on X-ray diffraction structural analysis pattern, transmission electron microscope, with the Pd morphological effect on ORR activity was identified

Multiple Active Contours Guided by Differential Evolution for Medical Image Segmentation

Science.gov (United States)

Cruz-Aceves, I.; Avina-Cervantes, J. G.; Lopez-Hernandez, J. M.; Rostro-Gonzalez, H.; Garcia-Capulin, C. H.; Torres-Cisneros, M.; Guzman-Cabrera, R.

2013-01-01

This paper presents a new image segmentation method based on multiple active contours guided by differential evolution, called MACDE. The segmentation method uses differential evolution over a polar coordinate system to increase the exploration and exploitation capabilities regarding the classical active contour model. To evaluate the performance of the proposed method, a set of synthetic images with complex objects, Gaussian noise, and deep concavities is introduced. Subsequently, MACDE is applied on datasets of sequential computed tomography and magnetic resonance images which contain the human heart and the human left ventricle, respectively. Finally, to obtain a quantitative and qualitative evaluation of the medical image segmentations compared to regions outlined by experts, a set of distance and similarity metrics has been adopted. According to the experimental results, MACDE outperforms the classical active contour model and the interactive Tseng method in terms of efficiency and robustness for obtaining the optimal control points and attains a high accuracy segmentation. PMID:23983809

Multiple Active Contours Guided by Differential Evolution for Medical Image Segmentation

Directory of Open Access Journals (Sweden)

I. Cruz-Aceves

2013-01-01

Full Text Available This paper presents a new image segmentation method based on multiple active contours guided by differential evolution, called MACDE. The segmentation method uses differential evolution over a polar coordinate system to increase the exploration and exploitation capabilities regarding the classical active contour model. To evaluate the performance of the proposed method, a set of synthetic images with complex objects, Gaussian noise, and deep concavities is introduced. Subsequently, MACDE is applied on datasets of sequential computed tomography and magnetic resonance images which contain the human heart and the human left ventricle, respectively. Finally, to obtain a quantitative and qualitative evaluation of the medical image segmentations compared to regions outlined by experts, a set of distance and similarity metrics has been adopted. According to the experimental results, MACDE outperforms the classical active contour model and the interactive Tseng method in terms of efficiency and robustness for obtaining the optimal control points and attains a high accuracy segmentation.

Electrochemical preparation and characteristics of Ni-Co-LaNi5 composite coatings as electrode materials for hydrogen evolution

International Nuclear Information System (INIS)

Wu Gang; Li Ning; Dai Changsong; Zhou Derui

2004-01-01

Electrocatalytic activity for the hydrogen evolution reaction on Ni-Co-LaNi 5 composite electrodes prepared by electrochemical codeposition technique was evaluated. The relationship between the current density for hydrogen evolution reaction and the amount of LaNi 5 particles in Ni-Co baths is like the well-known 'volcano plot'. The Surface morphology and microstructure of Ni-Co-LaNi 5 coatings were determined by means of scanning electron microscopy (SEM) and X-ray diffraction (XRD). The kinetic parameters were determined from electrochemical steady-state Tafel polarization and electrochemical impedance spectroscopy technology in 1 M NaOH solution. The values obtained for the apparent energies of activation are 32.48, 46.29 and 57.03 kJ mol -1 for the Ni-Co-LaNi 5 , Ni-Co and Ni electrodes, respectively. The hydrogen evolution reaction on Ni-Co-LaNi 5 proceeds via Volmer-Tafel reaction route with the mixed rate determining characteristics. The composite coating Ni-Co-LaNi 5 is catalytically more active than Ni and Ni-Co electrodes due to the increase in its real surface areas and the decrease in the apparent free energy of activation caused by the electrocatalytic synergistic effect of the Ni-Co alloys and the hydrogen storage intermetallic particles on the electrode surface

Cluster Based Hierarchical Routing Protocol for Wireless Sensor Network

OpenAIRE

Rashed, Md. Golam; Kabir, M. Hasnat; Rahim, Muhammad Sajjadur; Ullah, Shaikh Enayet

2012-01-01

The efficient use of energy source in a sensor node is most desirable criteria for prolong the life time of wireless sensor network. In this paper, we propose a two layer hierarchical routing protocol called Cluster Based Hierarchical Routing Protocol (CBHRP). We introduce a new concept called head-set, consists of one active cluster head and some other associate cluster heads within a cluster. The head-set members are responsible for control and management of the network. Results show that t...

Class network routing

Science.gov (United States)

Bhanot, Gyan [Princeton, NJ; Blumrich, Matthias A [Ridgefield, CT; Chen, Dong [Croton On Hudson, NY; Coteus, Paul W [Yorktown Heights, NY; Gara, Alan G [Mount Kisco, NY; Giampapa, Mark E [Irvington, NY; Heidelberger, Philip [Cortlandt Manor, NY; Steinmacher-Burow, Burkhard D [Mount Kisco, NY; Takken, Todd E [Mount Kisco, NY; Vranas, Pavlos M [Bedford Hills, NY

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.

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; Markstrom, Steven; Hay, Lauren E.; Woods, Ross; Arnold, Jeffrey R.; Brekke, Levi D.

2016-01-01

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.

Developing an eco-routing application.

Science.gov (United States)

2014-01-01

The study develops eco-routing algorithms and investigates and quantifies the system-wide impacts of implementing an eco-routing system. Two eco-routing algorithms are developed: one based on vehicle sub-populations (ECO-Subpopulation Feedback Assign...

Short-term radon activity concentration changes along the Underground Educational Tourist Route in the Old Uranium Mine in Kletno (Sudety Mts., SW Poland)

International Nuclear Information System (INIS)

Fijałkowska-Lichwa, Lidia

2014-01-01

Short-term 222 Rn activity concentration changes along the Underground Educational Tourist Route in the Old Uranium Mine in Kletno were studied, based on continuous measurements conducted between 16 May 2008 and 15 May 2010. The results were analysed in the context of numbers of visitors arriving at the facility in particular seasons and the time per day spent inside by staff and visitors. This choice was based on partially published earlier findings (Fijałkowska-Lichwa and Przylibski, 2011). Results for the year 2009 were analysed in depth, because it is the only period of observation covering a full calendar year. The year 2009 was also chosen for detailed analysis of short-term radon concentration changes, because in each period of this year (hour, month, season) fluctuations of noted values were the most visible. Attention has been paid to three crucial issues linked to the occurrence and behaviour of radon and to the radiological protection of workers and visitors at the tourist route in Kletno. The object of study is a complex of workings in a former uranium mine situated within a metamorphic rock complex in the most radon-prone area in Poland. The facility has been equipped with a mechanical ventilation system, which is turned on after the closing time and at the end of the working day for the visitor service staff, i.e. after 6 p.m. Short-term radon activity concentration changes along the Underground Educational Tourist Route in the Old Uranium Mine in Kletno are related to the activity of the facility's mechanical ventilation. Its inactivity in the daytime results in the fact that the highest values of 222 Rn activity concentration are observed at the time when the facility is open to visitors, i.e. between 10 a.m. and 6 p.m. The improper usage of the mechanical ventilation system is responsible for the extremely unfavourable working conditions, which persist in the facility for practically all year. The absence of appropriate radiological

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.

The Evolution of Lineage-Specific Regulatory Activities in the Human Embryonic Limb

OpenAIRE

Cotney, Justin; Leng, Jing; Yin, Jun; Reilly, Steven K.; DeMare, Laura E.; Emera, Deena; Ayoub, Albert E.; Rakic, Pasko; Noonan, James P.

2013-01-01

The evolution of human anatomical features likely involved changes in gene regulation during development. However, the nature and extent of human-specific developmental regulatory functions remain unknown. We obtained a genome-wide view of cis-regulatory evolution in human embryonic tissues by comparing the histone modification H3K27ac, which provides a quantitative readout of promoter and enhancer activity, during human, rhesus, and mouse limb development. Based on increased H3K27ac, we find...

An overview of smart grid routing algorithms

Science.gov (United States)

Wang, Junsheng; OU, Qinghai; Shen, Haijuan

2017-08-01

This paper summarizes the typical routing algorithm in smart grid by analyzing the communication business and communication requirements of intelligent grid. Mainly from the two kinds of routing algorithm is analyzed, namely clustering routing algorithm and routing algorithm, analyzed the advantages and disadvantages of two kinds of typical routing algorithm in routing algorithm and applicability.

Evolution of the central black hole in an active galactic nucleus. I. Evolution with a constant mass influx

International Nuclear Information System (INIS)

Park, S.J.; Vishniac, E.T.

1988-01-01

The long-term evolution of the central black hole in an active galactic nucleus (AGN), whose rotational energy is being extracted by the Blandford-Znajek process, was analyzed. The model is based on previous axisymmetric, stationary descriptions of the black hole and its magnetosphere, but includes the secular effects of the mass accretion rate. The properties of the black hole and the nonthermal radiation from its environment are calculated under the assumption that the mass influx is constant. It is noted that this model fails to explain the correlation of evolutionary time scale with luminosity or the extremely rapid evolution required for the most luminous sources. It is concluded that the evolution of AGNs is driven by a rapid decrease in mass accretion rate. Since the nature of an AGN is dependent on the ratio mass accretion/total mass, this leads to a conclusion that AGNs evolve from QSOs into the nuclei of Seyfert or radio galaxies. 20 references

Southern states' routing agency report

International Nuclear Information System (INIS)

1989-02-01

The Southern states' routing agency report is a compendium of 16-southern states' routing programs relative to the transportation of high-level radioactive materials. The report identifies the state-designated routing agencies as defined under 49 Code of Federal Regulations (CFR) Part 171 and provides a reference to the source ad scope of the agencies' rulemaking authority. Additionally, the state agency and contact designated by the state's governor to receive advance notification and shipment routing information under 10 CFR Parts 71 and 73 are also listed

Southern States' Routing Agency Report

International Nuclear Information System (INIS)

1990-03-01

The Southern States' Routing Agency Report is a compendium of 16-southern states' routing program for the transportation of high-level radioactive materials. The report identifies the state-designated routing agencies as defined under 49 Code of Federal Regulations (CFR) Part 171 and provides a reference to the source and scope of the agencies' rulemaking authority. Additionally, the state agency and contact designated by the state's governor to receive advance notification and shipment routing information under 10 CFR Parts 71 and 73 are also listed

Load Balancing Routing with Bounded Stretch

Directory of Open Access Journals (Sweden)

Chen Siyuan

2010-01-01

Full Text Available Routing in wireless networks has been heavily studied in the last decade. Many routing protocols are based on classic shortest path algorithms. However, shortest path-based routing protocols suffer from uneven load distribution in the network, such as crowed center effect where the center nodes have more load than the nodes in the periphery. Aiming to balance the load, we propose a novel routing method, called Circular Sailing Routing (CSR, which can distribute the traffic more evenly in the network. The proposed method first maps the network onto a sphere via a simple stereographic projection, and then the route decision is made by a newly defined "circular distance" on the sphere instead of the Euclidean distance in the plane. We theoretically prove that for a network, the distance traveled by the packets using CSR is no more than a small constant factor of the minimum (the distance of the shortest path. We also extend CSR to a localized version, Localized CSR, by modifying greedy routing without any additional communication overhead. In addition, we investigate how to design CSR routing for 3D networks. For all proposed methods, we conduct extensive simulations to study their performances and compare them with global shortest path routing or greedy routing in 2D and 3D wireless networks.

Three Southern high school biology teachers' perspectives on teaching evolution: Sociocultural influences

Science.gov (United States)

Kyzer, Peggy Mckewen

the Southern culture was a theme that cut across all the teachers' decisions. In particular, religious beliefs made teaching human evolution difficult. Other recurring themes included the influence of the textbook and factors that served as escape routes for the teachers electing to avoid evolution. The escape routes included the pressure of time, the mixed messages from the state board of education, and the double-edged sword of teacher autonomy.

Guidelines for selecting preferred highway routes for highway-route-controlled quantity shipments of radioactive materials

International Nuclear Information System (INIS)

1989-01-01

The document presents guidelines for use by State officials in selecting preferred routes for highway route controlled quantity shipments of radioactive materials. A methodology for analyzing and comparing safety factors of alternative routes is described. Technical information on the impacts of radioactive material transportation needed to apply the methodology is also presented. Application of the methodology will identify the route (or set of routes) that minimizes the radiological impacts from shipments of these radioactive materials within a given State. Emphasis in the document is on practical application of the methodology. Some details of the derivation of the methods and data are presented in the appendices. All references in the body of the report can be found listed in the Bibliography (Appendix F)

A dynamic continental runoff routing model applied to the last Northern Hemisphere deglaciation

Directory of Open Access Journals (Sweden)

H. Goelzer

2012-05-01

Full Text Available We describe and evaluate a dynamical continental runoff routing model for the Northern Hemisphere that calculates the runoff pathways in response to topographic modifications due to changes in ice thickness and isostatic adjustment. The algorithm is based on the steepest gradient method and takes as simplifying assumption that depressions are filled at all times and water drains through the lowest outlet points. It also considers changes in water storage and lake drainage in post-processing mode that become important in the presence of large ice dammed proglacial lakes. Although applicable to other scenarios as well, the model was conceived to study the routing of freshwater fluxes during the last Northern Hemisphere deglaciation. For that specific application we simulated the Northern Hemisphere ice sheets with an existing 3-D thermomechanical ice sheet model, which calculates changes in topography due to changes in ice cover and isostatic adjustment, as well as the evolution of freshwater fluxes resulting from surface ablation, iceberg calving and basal melt. The continental runoff model takes this input, calculates the drainage pathways and routes the freshwater fluxes to the surface grid points of an existing ocean model. This results in a chronology of temporally and spatially varying freshwater fluxes from the Last Glacial Maximum to the present day. We analyse the dependence of the runoff routing to grid resolution and parameters of the isostatic adjustment module of the ice sheet model.

Co-axial heterostructures integrating palladium/titanium dioxide with carbon nanotubes for efficient electrocatalytic hydrogen evolution

Science.gov (United States)

Valenti, Giovanni; Boni, Alessandro; Melchionna, Michele; Cargnello, Matteo; Nasi, Lucia; Bertoni, Giovanni; Gorte, Raymond J.; Marcaccio, Massimo; Rapino, Stefania; Bonchio, Marcella; Fornasiero, Paolo; Prato, Maurizio; Paolucci, Francesco

2016-12-01

Considering the depletion of fossil-fuel reserves and their negative environmental impact, new energy schemes must point towards alternative ecological processes. Efficient hydrogen evolution from water is one promising route towards a renewable energy economy and sustainable development. Here we show a tridimensional electrocatalytic interface, featuring a hierarchical, co-axial arrangement of a palladium/titanium dioxide layer on functionalized multi-walled carbon nanotubes. The resulting morphology leads to a merging of the conductive nanocarbon core with the active inorganic phase. A mechanistic synergy is envisioned by a cascade of catalytic events promoting water dissociation, hydride formation and hydrogen evolution. The nanohybrid exhibits a performance exceeding that of state-of-the-art electrocatalysts (turnover frequency of 15000 H2 per hour at 50 mV overpotential). The Tafel slope of ~130 mV per decade points to a rate-determining step comprised of water dissociation and formation of hydride. Comparative activities of the isolated components or their physical mixtures demonstrate that the good performance evolves from the synergistic hierarchical structure.

Strategies for Selecting Routes through Real-World Environments: Relative Topography, Initial Route Straightness, and Cardinal Direction.

Directory of Open Access Journals (Sweden)

Tad T Brunyé

Full Text Available Previous research has demonstrated that route planners use several reliable strategies for selecting between alternate routes. Strategies include selecting straight rather than winding routes leaving an origin, selecting generally south- rather than north-going routes, and selecting routes that avoid traversal of complex topography. The contribution of this paper is characterizing the relative influence and potential interactions of these strategies. We also examine whether individual differences would predict any strategy reliance. Results showed evidence for independent and additive influences of all three strategies, with a strong influence of topography and initial segment straightness, and relatively weak influence of cardinal direction. Additively, routes were also disproportionately selected when they traversed relatively flat regions, had relatively straight initial segments, and went generally south rather than north. Two individual differences, extraversion and sense of direction, predicted the extent of some effects. Under real-world conditions navigators indeed consider a route's initial straightness, cardinal direction, and topography, but these cues differ in relative influence and vary in their application across individuals.

Routing and scheduling problems

DEFF Research Database (Denmark)

Reinhardt, Line Blander

couple of decades. To deliver competitive service and price, transportation today needs to be cost effective. A company requiring for things to be shipped will aim at having the freight shipped as cheaply as possible while often satisfying certain time constraints. For the transportation company......, 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...... set cost making the cost of the individual vehicle routes inter-dependant. Depending on the problem type, the size of the problems and time available for solving, different solution methods can be applicable. In this thesis both heuristic methods and several exact methods are investigated depending...

Potential market for natural gas. Route Juiz de Fora - Belo Horizonte, Minas Gerais State, Brazil. 1995-2005

International Nuclear Information System (INIS)

1989-01-01

The market study of natural gas in the route of Juiz de Fora - Belo Horizonte is important for the process of evaluation, planning and negotiation of this energetic coming for Minas Gerais State. The evolution of the consumption potential in this region is analysed, with the forecasting of socio-economic growth until 2005. The residential, commercial, transport and industry sectors are studied. (author)

Risk assessment of alternative proliferation routes

International Nuclear Information System (INIS)

Ahmed, S.; Husseiny, A.A.

1982-01-01

Multi-Attribute Decision Theory is applied to rank II alternative routes to nuclear proliferation in order of difficulty in acquiring nuclear weapons by nonnuclear countries. The method is based on reducing the various variables affecting the decision to a single function providing a measure for the proliferation route. The results indicate that the most difficult route to obtain atomic weapons is through nuclear power reactors, specifically the liquid-metal fast breeder reactor, heavy water Canada deuterium uranium reactor, and light water reactors such as boiling water and pressurized water reactors. The easiest routes are supercritical centrifuge isotope separation, laser isotope separation, and research reactor. However, nonnuclear routes available that result in substantial damage to life and property are easier than any nuclear route

Transportation Routing Analysis Geographic Information System -- TRAGIS, progress on improving a routing tool

International Nuclear Information System (INIS)

Johnson, P.E.; Lester, P.B.

1998-05-01

The Transportation Routing Analysis Geographic Information System (TRAGIS) model provides a useful tool to calculate and analyze transportation routes for radioactive materials within the continental US. This paper outlines some of the features available in this model

Learning from the Route: a Pilot Project on Landscape Reading along the Itinerary of Via Lauretana Senese

Directory of Open Access Journals (Sweden)

Chiara Serenelli

2017-01-01

Full Text Available The essay investigates the opportunities generated by recovering a European Pilgrimage Route’s pathway as device for landscape perception and territorial analysis. It is focused on a project conducted by Verdiana Network in collaboration with the Municipality of Asciano (Siena. The project aims to activate processes of landscape planning and management, and promote local tourism within the context of Asciano’s rural landscape and among the cultural and natural heritage intercepted by this pilgrimage route. It concerns the Siena branch of the Via Lauretana, the pilgrimage route toward the Sanctuary of Loreto in the Marche Region. The project focuses on the landscape structure of the route, modelled by the territorial dimension and spatial configuration of the itinerary, together with the social processes of landscape perception activated by the route itself. From this point of view, the project consisted of a process of discovering the landscape along the route and intercepting polar elements that make the itinerary the basis for the development of local tourism and cultural activities.

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.

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...

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...

A MODIFIED ROUTE DISCOVERY APPROACH FOR DYNAMIC SOURCE ROUTING (DSR PROTOCOL IN MOBILE AD-HOC NETWORKS

Directory of Open Access Journals (Sweden)

Alaa Azmi Allahham

2017-02-01

Full Text Available Mobile Ad-hoc networks (MANETs involved in many applications, whether commercial or military because of their characteristics that do not depend on the infrastructure as well as the freedom movement of their elements, but in return has caused this random mobility of the nodes many of the challenges, where the routing is considered one of these challenges. There are many types of routing protocols that operate within MANET networks, which responsible for finding paths between the source and destination nodes with the modernization of these paths which are constantly changing due to the dynamic topology of the network stemming from the constant random movement of the nodes. The DSR (Dynamic Source Routing routing protocol algorithm is one of these routing protocols which consist of two main stages; route discovery and maintenance, where the route discovery algorithm operates based on blind flooding of request messages. blind flooding is considered as the most well known broadcasting mechanism, it is inefficient in terms of communication and resource utilization, which causing increasing the probability of collisions, repeating send several copies of the same message, as well as increasing the delay. Hence, a new mechanism in route discovery stage and in caching the routes in DSR algorithm according to the node's location in the network and the direction of the broadcast is proposed for better performance especially in terms of delay as well as redundant packets rate. The implementation of proposed algorithms showed positive results in terms of delay, overhead, and improve the performance of MANETs in general.

Route-specific analysis for radioactive materials transportation

International Nuclear Information System (INIS)

1986-01-01

This report addresses a methodology for route-specific analysis, of which route-selection is one aspect. Identification and mitigation of specific hazards along a chosen route is another important facet of route-specific analysis. Route-selection and route-specific mitigation are two tools to be used in minimizing the risk of radioactive materials transportation and promoting public confidence. Other tools exist to improve the safety of transportation under the Nuclear Waste Policy Act. Selection of a transportation mode and other, non-route-specific measures, such as improved driver training and improved cask designs, are additional tools to minimize transportation risk and promote public confidence. This report addresses the route-specific analysis tool and does not attempt to evaluate its relative usefulness as compared to other available tools. This report represents a preliminary attempt to develop a route-specific analysis methodlogy. The Western Interstate Energy Board High-Level Waste Committee has formed a Route-Specific Analysis Task Force which will build upon the methodology proposed in this Staff Report. As western states continue to investigate route-specific analysis issues, it is expected that the methodology will evolve into a more refined product representing the views of a larger group of interested parties in the West

Route related data of shopping centre visitors and geographical information systems

NARCIS (Netherlands)

Waerden, van der P.J.H.J.; Borgers, A.W.J.; Timmermans, H.J.P.

1996-01-01

Pedestrian route information can support different research activities such as the calculation of economic performances of shopping streets, the evaluation of parking policy measures, and the development of pedestrian design standards. These research activities are helpful in planning and designing

Bellman Ford algorithm - in Routing Information Protocol (RIP)

Science.gov (United States)

Krianto Sulaiman, Oris; Mahmud Siregar, Amir; Nasution, Khairuddin; Haramaini, Tasliyah

2018-04-01

In a large scale network need a routing that can handle a lot number of users, one of the solutions to cope with large scale network is by using a routing protocol, There are 2 types of routing protocol that is static and dynamic, Static routing is manually route input based on network admin, while dynamic routing is automatically route input formed based on existing network. Dynamic routing is efficient used to network extensively because of the input of route automatic formed, Routing Information Protocol (RIP) is one of dynamic routing that uses the bellman-ford algorithm where this algorithm will search for the best path that traversed the network by leveraging the value of each link, so with the bellman-ford algorithm owned by RIP can optimize existing networks.

Dicationic ionic liquid mediated fabrication of Au@Pt nanoparticles supported on reduced graphene oxide with highly catalytic activity for oxygen reduction and hydrogen evolution

Science.gov (United States)

Shi, Ya-Cheng; Chen, Sai-Sai; Feng, Jiu-Ju; Lin, Xiao-Xiao; Wang, Weiping; Wang, Ai-Jun

2018-05-01

Ionic liquids as templates or directing agents have attracted great attention for shaping-modulated synthesis of advanced nanomaterials. In this work, reduced graphene oxide supported uniform core-shell Au@Pt nanoparticles (Au@Pt NPs/rGO) were fabricated by a simple one-pot aqueous approach, using N-methylimidazolium-based dicationic ionic liquid (1,1-bis(3-methylimadazoilum-1-yl)butylene bromide, [C4(Mim)2]2Br) as the shape-directing agent. The morphology evolution, structural information and formation mechanism of Au@Pt NPs anchored on rGO were investigated by a series of characterization techniques. The obtained nanocomposites displayed superior electrocatalytic features toward hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) compared with commercial Pt/C catalyst. This approach provides a novel route for facile synthesis of nanocatalysts in fuel cells.

Sex differences in neural activation following different routes of oxytocin administration in awake adult rats.

Science.gov (United States)

Dumais, Kelly M; Kulkarni, Praveen P; Ferris, Craig F; Veenema, Alexa H

2017-07-01

The neuropeptide oxytocin (OT) regulates social behavior in sex-specific ways across species. OT has promising effects on alleviating social deficits in sex-biased neuropsychiatric disorders. However little is known about potential sexually dimorphic effects of OT on brain function. Using the rat as a model organism, we determined whether OT administered centrally or peripherally induces sex differences in brain activation. Functional magnetic resonance imaging was used to examine blood oxygen level-dependent (BOLD) signal intensity changes in the brains of awake rats during the 20min following intracerebroventricular (ICV; 1μg/5μl) or intraperitoneal (IP; 0.1mg/kg) OT administration as compared to baseline. ICV OT induced sex differences in BOLD activation in 26 out of 172 brain regions analyzed, with 20 regions showing a greater volume of activation in males (most notably the nucleus accumbens and insular cortex), and 6 regions showing a greater volume of activation in females (including the lateral and central amygdala). IP OT also elicited sex differences in BOLD activation with a greater volume of activation in males, but this activation was found in different and fewer (10) brain regions compared to ICV OT. In conclusion, exogenous OT modulates neural activation differently in male versus female rats with the pattern and magnitude, but not the direction, of sex differences depending on the route of administration. These findings highlight the need to include both sexes in basic and clinical studies to fully understand the role of OT on brain function. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nothing in Evolution Makes Sense Except in the Light of Genomics: Read–Write Genome Evolution as an Active Biological Process

Directory of Open Access Journals (Sweden)

James A. Shapiro

2016-06-01

Full Text Available The 21st century genomics-based analysis of evolutionary variation reveals a number of novel features impossible to predict when Dobzhansky and other evolutionary biologists formulated the neo-Darwinian Modern Synthesis in the middle of the last century. These include three distinct realms of cell evolution; symbiogenetic fusions forming eukaryotic cells with multiple genome compartments; horizontal organelle, virus and DNA transfers; functional organization of proteins as systems of interacting domains subject to rapid evolution by exon shuffling and exonization; distributed genome networks integrated by mobile repetitive regulatory signals; and regulation of multicellular development by non-coding lncRNAs containing repetitive sequence components. Rather than single gene traits, all phenotypes involve coordinated activity by multiple interacting cell molecules. Genomes contain abundant and functional repetitive components in addition to the unique coding sequences envisaged in the early days of molecular biology. Combinatorial coding, plus the biochemical abilities cells possess to rearrange DNA molecules, constitute a powerful toolbox for adaptive genome rewriting. That is, cells possess “Read–Write Genomes” they alter by numerous biochemical processes capable of rapidly restructuring cellular DNA molecules. Rather than viewing genome evolution as a series of accidental modifications, we can now study it as a complex biological process of active self-modification.

Research on the Method of Urban Waterlogging Flood Routing Based on Hexagonal Grid

Directory of Open Access Journals (Sweden)

LAI Guangling

2016-12-01

Full Text Available An evolution of the urban waterlogging flood routing was studied in this paper based on the method of hexagonal grid modeling. Using the method of discrete grid, established an urban geometry model on account of the regular multi-scale discrete grid. With the fusion of 3D topographic survey data and 2D building vector data, formed a regular network model of surface. This model took multi special block into account, such as urban terrain and buildings. On this basis, a method of reverse flow deduction was proposed, which was an inverse computation from the state of flood to the evolution process. That is, based on the water depth of flood, made use of the connectivity with the outfall to calculate the range of water logging, and then implemented the urban waterlogging flood simulation deduction. The test indicated that, this method can implement the evolution of urban waterlogging scenario deduction effectively. And the correlational research could provide scientific basis for urban disaster prevention and emergency decision-making.

Predicting transportation routes for radioactive wastes

International Nuclear Information System (INIS)

Joy, D.S.; Johnson, P.E.; Clarke, D.B.; McGuire, S.C.

1981-01-01

Oak Ridge National Laboratory (ORNL) has been involved in transportation logistics of radioactive wastes as part of the overall waste transportation program. A Spent Fuel Logistics Model (SFLM), was developed to predict overall material balances representing the flow of spent fuel assemblies from reactors to away-from-reactor storage facilities and/or to federal repositories. The transportation requirements to make these shipments are also itemized. The next logical step in the overall transportation project was the development of a set of computer codes which would predict likely transportation routes for waste shipments. Two separate routing models are now operational at ORNL. Routes for truck transport can be estimated with the HIGHWAY program, and rail and barge routes can be predicted with the INTERLINE model. This paper discusses examples of the route estimates and applications of the routing models

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.

RSRP: A Robust Secure Routing Protocol in MANET

Directory of Open Access Journals (Sweden)

Sinha Ditipriya

2014-05-01

Full Text Available In this paper, we propose a novel algorithm RSRP to build a robust secure routing protocol in mobile ad-hoc networks (MANETs. This algorithm is based on some basic schemes such as RSA_CRT for encryption and decryption of messages; CRT for safety key generation, Shamir’s secret sharing principle for generation of secure routes. Those routes which are free from any malicious node and which belong to the set of disjoint routes between a source-destination pair are considered as probable routes. Shamir’s secret sharing principle is applied on those probable routes to obtain secure routes. Finally, most trustworthy and stable route is selected among those secure routes. Selection of the final route depends on some criteria of the nodes present in a route e.g.: battery power, mobility and trust value. In addition, complexity of key generation is reduced to a large extent by using RSA-CRT instead of RSA. In turn, the routing becomes less expensive and most secure and robust one. Performance of this routing protocol is then compared with non-secure routing protocols (AODV and DSR, secure routing scheme using secret sharing, security routing protocol using ZRP and SEAD depending on basic characteristics of these protocols. All such comparisons show that RSRP shows better performance in terms of computational cost, end-to-end delay and packet dropping in presence of malicious nodes in the MANET, keeping the overhead in terms of control packets same as other secure routing protocols.

Human risk assessment of dermal and inhalation exposures to chemicals assessed by route-to-route extrapolation: the necessity of kinetic data.

Science.gov (United States)

Geraets, Liesbeth; Bessems, Jos G M; Zeilmaker, Marco J; Bos, Peter M J

2014-10-01

In toxicity testing the oral route is in general the first choice. Often, appropriate inhalation and dermal toxicity data are absent. Risk assessment for these latter routes usually has to rely on route-to-route extrapolation starting from oral toxicity data. Although it is generally recognized that the uncertainties involved are (too) large, route-to-route extrapolation is applied in many cases because of a strong need of an assessment of risks linked to a given exposure scenario. For an adequate route-to-route extrapolation the availability of at least some basic toxicokinetic data is a pre-requisite. These toxicokinetic data include all phases of kinetics, from absorption (both absorbed fraction and absorption rate for both the starting route and route of interest) via distribution and biotransformation to excretion. However, in practice only differences in absorption between the different routes are accounted for. The present paper demonstrates the necessity of route-specific absorption data by showing the impact of its absence on the uncertainty of the human health risk assessment using route-to-route extrapolation. Quantification of the absorption (by in vivo, in vitro or in silico methods), particularly for the starting route, is considered essential. Copyright © 2014 Elsevier Inc. All rights reserved.

Silencing urease: A key evolutionary step that facilitated the adaptation of Yersinia pestis to the flea-borne transmission route

Science.gov (United States)

Chouikha, Iman; Hinnebusch, B. Joseph

2014-01-01

The arthropod-borne transmission route of Yersinia pestis, the bacterial agent of plague, is a recent evolutionary adaptation. Yersinia pseudotuberculosis, the closely related food-and water-borne enteric species from which Y. pestis diverged less than 6,400 y ago, exhibits significant oral toxicity to the flea vectors of plague, whereas Y. pestis does not. In this study, we identify the Yersinia urease enzyme as the responsible oral toxin. All Y. pestis strains, including those phylogenetically closest to the Y. pseudotuberculosis progenitor, contain a mutated ureD allele that eliminated urease activity. Restoration of a functional ureD was sufficient to make Y. pestis orally toxic to fleas. Conversely, deletion of the urease operon in Y. pseudotuberculosis rendered it nontoxic. Enzymatic activity was required for toxicity. Because urease-related mortality eliminates 30–40% of infective flea vectors, ureD mutation early in the evolution of Y. pestis was likely subject to strong positive selection because it significantly increased transmission potential. PMID:25453069

Silencing urease: a key evolutionary step that facilitated the adaptation of Yersinia pestis to the flea-borne transmission route.

Science.gov (United States)

Chouikha, Iman; Hinnebusch, B Joseph

2014-12-30

The arthropod-borne transmission route of Yersinia pestis, the bacterial agent of plague, is a recent evolutionary adaptation. Yersinia pseudotuberculosis, the closely related food-and water-borne enteric species from which Y. pestis diverged less than 6,400 y ago, exhibits significant oral toxicity to the flea vectors of plague, whereas Y. pestis does not. In this study, we identify the Yersinia urease enzyme as the responsible oral toxin. All Y. pestis strains, including those phylogenetically closest to the Y. pseudotuberculosis progenitor, contain a mutated ureD allele that eliminated urease activity. Restoration of a functional ureD was sufficient to make Y. pestis orally toxic to fleas. Conversely, deletion of the urease operon in Y. pseudotuberculosis rendered it nontoxic. Enzymatic activity was required for toxicity. Because urease-related mortality eliminates 30-40% of infective flea vectors, ureD mutation early in the evolution of Y. pestis was likely subject to strong positive selection because it significantly increased transmission potential.

Electrochemical preparation and characteristics of Ni-Co-LaNi{sub 5} composite coatings as electrode materials for hydrogen evolution

Energy Technology Data Exchange (ETDEWEB)

Wu Gang; Li Ning; Dai Changsong; Zhou Derui

2004-02-15

Electrocatalytic activity for the hydrogen evolution reaction on Ni-Co-LaNi{sub 5} composite electrodes prepared by electrochemical codeposition technique was evaluated. The relationship between the current density for hydrogen evolution reaction and the amount of LaNi{sub 5} particles in Ni-Co baths is like the well-known 'volcano plot'. The Surface morphology and microstructure of Ni-Co-LaNi{sub 5} coatings were determined by means of scanning electron microscopy (SEM) and X-ray diffraction (XRD). The kinetic parameters were determined from electrochemical steady-state Tafel polarization and electrochemical impedance spectroscopy technology in 1 M NaOH solution. The values obtained for the apparent energies of activation are 32.48, 46.29 and 57.03 kJ mol{sup -1} for the Ni-Co-LaNi{sub 5}, Ni-Co and Ni electrodes, respectively. The hydrogen evolution reaction on Ni-Co-LaNi{sub 5} proceeds via Volmer-Tafel reaction route with the mixed rate determining characteristics. The composite coating Ni-Co-LaNi{sub 5} is catalytically more active than Ni and Ni-Co electrodes due to the increase in its real surface areas and the decrease in the apparent free energy of activation caused by the electrocatalytic synergistic effect of the Ni-Co alloys and the hydrogen storage intermetallic particles on the electrode surface.

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...

The waste collection vehicle routing problem with time windows in a city logistics context

DEFF Research Database (Denmark)

Buhrkal, Katja Frederik; Larsen, Allan; Røpke, Stefan

2012-01-01

Collection of waste is an important logistic activity within any city. In this paper we study how to collect waste in an efficient way. We study the Waste Collection Vehicle Routing Problem with Time Window which is concerned with finding cost optimal routes for garbage trucks such that all garbage...

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.

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.

Capacity Constrained Routing Algorithms for Evacuation Route Planning

National Research Council Canada - National Science Library

Lu, Qingsong; George, Betsy; Shekhar, Shashi

2006-01-01

.... In this paper, we propose a new approach, namely a capacity constrained routing planner which models capacity as a time series and generalizes shortest path algorithms to incorporate capacity constraints...

Entanglement-Gradient Routing for Quantum Networks.

Science.gov (United States)

Gyongyosi, Laszlo; Imre, Sandor

2017-10-27

We define the entanglement-gradient routing scheme for quantum repeater networks. The routing framework fuses the fundamentals of swarm intelligence and quantum Shannon theory. Swarm intelligence provides nature-inspired solutions for problem solving. Motivated by models of social insect behavior, the routing is performed using parallel threads to determine the shortest path via the entanglement gradient coefficient, which describes the feasibility of the entangled links and paths of the network. The routing metrics are derived from the characteristics of entanglement transmission and relevant measures of entanglement distribution in quantum networks. The method allows a moderate complexity decentralized routing in quantum repeater networks. The results can be applied in experimental quantum networking, future quantum Internet, and long-distance quantum communications.

Biosynthetic routes of hydroxylated carotenoids (xanthophylls) in Marchantia polymorpha, and production of novel and rare xanthophylls through pathway engineering in Escherichia coli.

Science.gov (United States)

Takemura, Miho; Maoka, Takashi; Misawa, Norihiko

2015-03-01

MpBHY codes for a carotene β-ring 3(,3')-hydroxylase responsible for both zeaxanthin and lutein biosynthesis in liverwort. MpCYP97C functions as an ε-ring hydroxylase (zeinoxanthin 3'-hydroxylase) to produce lutein in liverwort. Xanthophylls are oxygenated or hydroxylated carotenes that are most abundant in the light-harvesting complexes of plants. The plant-type xanthophylls consist of α-xanthophyll (lutein) and β-xanthophylls (zeaxanthin, antheraxanthin, violaxanthin and neoxanthin). The α-xanthophyll and β-xanthophylls are derived from α-carotene and β-carotene by carotene hydroxylase activities, respectively. β-Ring 3,3'-hydroxylase that mediates the route of zeaxanthin from β-carotene via β-cryptoxanthin is present in higher plants and is encoded by the BHY (BCH) gene. On the other hand, CYP97A (or BHY) and CYP97C genes are responsible for β-ring 3-hydroxylation and ε-ring 3'-hydroxylation, respectively, in routes from α-carotene to lutein. To elucidate the evolution of the biosynthetic routes of such hydroxylated carotenoids from carotenes in land plants, we identified and functionally analyzed carotenoid hydroxylase genes of liverwort Marchantia polymorpha L. Three genes homologous to higher plants, BHY, CYP97A, and CYP97C, were isolated and named MpBHY, MpCYP97A, and MpCYP97C, respectively. MpBHY was found to code for β-ring hydroxylase, which is responsible for both routes starting from β-carotene and α-carotene. MpCYP97C functioned as an ε-ring hydroxylase not for α-carotene but for zeinoxanthin, while MpCYP97A showed no hydroxylation activity for β-carotene or α-carotene. These findings suggest the original functions of the hydroxylation enzymes of carotenes in land plants, which are thought to diversify in higher plants. In addition, we generated recombinant Escherichia coli cells, which produced rare and novel carotenoids such as α-echinenone and 4-ketozeinoxanthin, through pathway engineering using bacterial carotenogenic genes

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...

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...

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.

Road Routes for Waste Disposal - MDC_RecyclingRoute

Data.gov (United States)

NSGIC Local Govt | GIS Inventory — 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...

Evolution of Bacillus thuringiensis Cry toxins insecticidal activity.

Science.gov (United States)

Bravo, Alejandra; Gómez, Isabel; Porta, Helena; García-Gómez, Blanca Ines; Rodriguez-Almazan, Claudia; Pardo, Liliana; Soberón, Mario

2013-01-01

Insecticidal Cry proteins produced by Bacillus thuringiensis are use worldwide in transgenic crops for efficient pest control. Among the family of Cry toxins, the three domain Cry family is the better characterized regarding their natural evolution leading to a large number of Cry proteins with similar structure, mode of action but different insect specificity. Also, this group is the better characterized regarding the study of their mode of action and the molecular basis of insect specificity. In this review we discuss how Cry toxins have evolved insect specificity in nature and analyse several cases of improvement of Cry toxin action by genetic engineering, some of these examples are currently used in transgenic crops. We believe that the success in the improvement of insecticidal activity by genetic evolution of Cry toxins will depend on the knowledge of the rate-limiting steps of Cry toxicity in different insect pests, the mapping of the specificity binding regions in the Cry toxins, as well as the improvement of mutagenesis strategies and selection procedures. © 2012 The Authors. Microbial Biotechnology © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

Porcelain tiles by the dry route

International Nuclear Information System (INIS)

Melchiades, F. G.; Daros, M. T.; Boschi, A. O.

2010-01-01

In Brazil, the second largest tile producer of the world, at present, 70% of the tiles are produced by the dry route. One of the main reasons that lead to this development is the fact that the dry route uses approximately 30% less thermal energy them the traditional wet route. The increasing world concern with the environment and the recognition of the central role played by the water also has pointed towards privileging dry processes. In this context the objective of the present work is to study the feasibility of producing high quality porcelain tiles by the dry route. A brief comparison of the dry and wet route, in standard conditions industrially used today to produce tiles that are not porcelain tiles, shows that there are two major differences: the particle sizes obtained by the wet route are usually considerably finer and the capability of mixing the different minerals, the intimacy of the mixture, is also usually better in the wet route. The present work studied the relative importance of these differences and looked for raw materials and operational conditions that would result in better performance and glazed porcelain tiles of good quality. (Author) 7 refs.

VANET Routing Protocols: Pros and Cons

OpenAIRE

Paul, Bijan; Ibrahim, Md.; 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 h...

Effect of exposure routes on the relationships of lethal toxicity to rats from oral, intravenous, intraperitoneal and intramuscular routes.

Science.gov (United States)

Ning, Zhong H; Long, Shuang; Zhou, Yuan Y; Peng, Zi Y; Sun, Yi N; Chen, Si W; Su, Li M; Zhao, Yuan H

2015-11-01

The lethal toxicity values (log 1/LD(50)) of 527 aliphatic and aromatic compounds in oral, intravenous, intramuscular and intraperitoneal routes were used to investigate the relationships of log 1/LD(50) from different exposure routes. Regression analysis shows that the log 1/LD(50) values are well correlated between intravenous and intraperitoneal or intramuscular injections. However, the correlations between oral and intravenous or intraperitoneal routes are relatively poor. Comparison of the average residuals indicates that intravenous injection is the most sensitive exposure route and oral administration is the least sensitive exposure route. This is attributed to the difference in kinetic process of toxicity testing. The toxic effect of a chemical can be similar or significantly different between exposure routes, depending on the absorption rates of chemicals into blood. Inclusion of hydrophobic parameter and fractions of ionic forms can improve the correlations between intravenous and intraperitoneal or oral routes, but not between intraperitoneal and oral routes. This is due to the differences of absorption rate in different exposure environments from different routes. Several factors, such as experimental uncertainty, metabolism and toxic kinetics, can affect the correlations between intravenous and intraperitoneal or oral routes. Copyright © 2015 Elsevier Inc. All rights reserved.

Computational representation of Alzheimer's disease evolution applied to a cooking activity.

Science.gov (United States)

Serna, Audrey; Rialle, Vincent; Pigot, Hélène

2006-01-01

This article presents a computational model and a simulation of the decrease of activities of daily living performances due to Alzheimer's disease. The disease evolution is simulated thanks to the cognitive architecture ACT-R. Activities are represented according to the retrieval of semantic units in declarative memory and the trigger of rules in procedural memory. The simulation of Alzheimer's disease decrease is simulated thanks to the variation of subsymbolic parameters. The model is applied to a cooking activity. Simulation of 100 hundred subjects shows results similar to those realised in a standardized assessment with human subjects.

From 3D to 2D Co and Ni Oxyhydroxide Catalysts: Elucidation of the Active Site and Influence of Doping on the Oxygen Evolution Activity

DEFF Research Database (Denmark)

Tripkovic, Vladimir; Hansen, Heine Anton; Vegge, Tejs

2017-01-01

Layered oxyhydroxides (ox-hys) of Ni and Co are among the most active catalysts for oxygen evolution in alkaline media. Their activities can be further tuned by delamination into single-layer oxide sheets or by means of doping. The active site for the reaction and how doping and delamination...... investigate the role of terrace and edge sites and use stability, catalytic activity, and electronic conductivity as evaluation criteria to pinpoint the best catalysts. We arrive at several important conclusions: the ox-hy surface is fully oxidized under oxygen evolution conditions, bulk terraces...

The Development of New Trans-border Water Routes in the South-East Baltic: Methodology and Practice

Directory of Open Access Journals (Sweden)

Kropinova E.

2014-09-01

Full Text Available This article offers an integrative approach to the development of trans-border water routes. Route development is analysed in the context of system approach as integration of geographical, climatic, meaning-related, infrastructural, and marketing components. The authors analyse the Russian and European approaches to route development. The article focuses on the institutional environment and tourist and recreational resources necessary for water route development. Special attention is paid to the activity aspect of tourist resources. At the same time, the development of all routes included an analysis of physical geographical, technological, infrastructural, economic, political, and social aspects. The case of water routes developed in the framework of the Crossroads 2.0 international project is used to describe the practical implementation of the theoretical assumptions. The work also tests the methodology of point rating for objects that can be potentially included in the route. The creation of trans-border water routes is presented as an innovative technology of identifying a territory’s potential and its further development. The authors stress the trans-border nature of water routes is their essential characteristic based on the natural properties of water routes.

Highway and interline transportation routing models

International Nuclear Information System (INIS)

Joy, D.S.; Johnson, P.E.

1994-01-01

The potential impacts associated with the transportation of hazardous materials are important issues to shippers, carriers, and the general public. Since transportation routes are a central characteristic in most of these issues, the prediction of likely routes is the first step toward the resolution of these issues. In addition, US Department of Transportation requirements (HM-164) mandate specific routes for shipments of highway controlled quantities of radioactive materials. In response to these needs, two routing models have been developed at Oak Ridge National Laboratory under the sponsorship of the U.S. Department of Energy (DOE). These models have been designated by DOE's Office of Environmental Restoration and Waste Management, Transportation Management Division (DOE/EM) as the official DOE routing models. Both models, HIGHWAY and INTERLINE, are described

Method and System for Dynamic Automated Corrections to Weather Avoidance Routes for Aircraft in En Route Airspace

Science.gov (United States)

McNally, B. David (Inventor); Erzberger, Heinz (Inventor); Sheth, Kapil (Inventor)

2015-01-01

A dynamic weather route system automatically analyzes routes for in-flight aircraft flying in convective weather regions and attempts to find more time and fuel efficient reroutes around current and predicted weather cells. The dynamic weather route system continuously analyzes all flights and provides reroute advisories that are dynamically updated in real time while the aircraft are in flight. The dynamic weather route system includes a graphical user interface that allows users to visualize, evaluate, modify if necessary, and implement proposed reroutes.

Temporal phases of activity-dependent plasticity and memory are mediated by compartmentalized routing of MAPK signaling in aplysia sensory neurons.

Science.gov (United States)

Shobe, Justin L; Zhao, Yali; Stough, Shara; Ye, Xiaojing; Hsuan, Vickie; Martin, Kelsey C; Carew, Thomas J

2009-01-15

An activity-dependent form of intermediate memory (AD-ITM) for sensitization is induced in Aplysia by a single tail shock that gives rise to plastic changes (AD-ITF) in tail sensory neurons (SNs) via the interaction of action potential firing in the SN coupled with the release of serotonin in the CNS. Activity-dependent long-term facilitation (AD-LTF, lasting >24hr) requires protein synthesis dependent persistent mitogen-activated protein kinase (MAPK) activation and translocation to the SN nucleus. We now show that the induction of the earlier temporal phase (AD-ITM and AD-ITF), which is translation and transcription independent, requires the activation of a compartmentally distinct novel signaling cascade that links second messengers, MAPK and PKC into a unified pathway within tail SNs. Since both AD-ITM and AD-LTM require MAPK activity, these collective findings suggest that presynaptic SNs route the flow of molecular information to distinct subcellular compartments during the induction of activity-dependent long-lasting memories.

Cobalt hydroxide nanoflakes and their application as supercapacitors and oxygen evolution catalysts

Science.gov (United States)

Rovetta, A. A. S.; Browne, M. P.; Harvey, A.; Godwin, I. J.; Coleman, J. N.; Lyons, M. E. G.

2017-09-01

Finding alternative routes to access and store energy has become a major issue recently. Transition metal oxides have shown promising behaviour as catalysts and supercapacitors. Recently, liquid exfoliation of bulk metal oxides appears to be an effective route which provides access to two-dimensional (2D) nano-flakes, the size of which can be easily selected. These 2D materials exhibit excellent electrochemical charge storage and catalytic activity for the oxygen evolution reaction. In this study, various sized selected cobalt hydroxide nano-flake materials are fabricated by this time efficient and highly reproducible process. Subsquently, the electrochemical properties of the standard size Co(OH)2 nanoflakes were investigated. The oxide modified electrodes were prepared by spraying the metal oxide flake suspension onto a porous conductive support electrode foam, either glassy carbon or nickel. The cobalt hydroxide/nickel foam system was found to have an overpotential value at 10 mA cm-2 in 1 M NaOH as low as 280 mV and an associated redox capacitance exhibiting numerical values up to 1500 F g-1, thereby making it a viable dual use electrode.

Topology control of tactical wireless sensor networks using energy efficient zone routing

Directory of Open Access Journals (Sweden)

Preetha Thulasiraman

2016-02-01

Full Text Available The US Department of Defense (DoD routinely uses wireless sensor networks (WSNs for military tactical communications. Sensor node die-out has a significant impact on the topology of a tactical WSN. This is problematic for military applications where situational data is critical to tactical decision making. To increase the amount of time all sensor nodes remain active within the network and to control the network topology tactically, energy efficient routing mechanisms must be employed. In this paper, we aim to provide realistic insights on the practical advantages and disadvantages of using established routing techniques for tactical WSNs. We investigate the following established routing algorithms: direct routing, minimum transmission energy (MTE, Low Energy Adaptive Cluster Head routing (LEACH, and zone clustering. Based on the node die out statistics observed with these algorithms and the topological impact the node die outs have on the network, we develop a novel, energy efficient zone clustering algorithm called EZone. Via extensive simulations using MATLAB, we analyze the effectiveness of these algorithms on network performance for single and multiple gateway scenarios and show that the EZone algorithm tactically controls the topology of the network, thereby maintaining significant service area coverage when compared to the other routing algorithms.

Pithy Review on Routing Protocols in Wireless Sensor Networks and Least Routing Time Opportunistic Technique in WSN

Science.gov (United States)

Salman Arafath, Mohammed; Rahman Khan, Khaleel Ur; Sunitha, K. V. N.

2018-01-01

Nowadays due to most of the telecommunication standard development organizations focusing on using device-to-device communication so that they can provide proximity-based services and add-on services on top of the available cellular infrastructure. An Oppnets and wireless sensor network play a prominent role here. Routing in these networks plays a significant role in fields such as traffic management, packet delivery etc. Routing is a prodigious research area with diverse unresolved issues. This paper firstly focuses on the importance of Opportunistic routing and its concept then focus is shifted to prime aspect i.e. on packet reception ratio which is one of the highest QoS Awareness parameters. This paper discusses the two important functions of routing in wireless sensor networks (WSN) namely route selection using least routing time algorithm (LRTA) and data forwarding using clustering technique. Finally, the simulation result reveals that LRTA performs relatively better than the existing system in terms of average packet reception ratio and connectivity.

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.

Research on Innovating, Applying Multiple Paths Routing Technique Based on Fuzzy Logic and Genetic Algorithm for Routing Messages in Service - Oriented Routing

Directory of Open Access Journals (Sweden)

Nguyen Thanh Long

2015-02-01

Full Text Available MANET (short for Mobile Ad-Hoc Network consists of a set of mobile network nodes, network configuration changes very fast. In content based routing, data is transferred from source node to request nodes is not based on destination addresses. Therefore, it is very flexible and reliable, because source node does not need to know destination nodes. If We can find multiple paths that satisfies bandwidth requirement, split the original message into multiple smaller messages to transmit concurrently on these paths. On destination nodes, combine separated messages into the original message. Hence it can utilize better network resources, causes data transfer rate to be higher, load balancing, failover. Service Oriented Routing is inherited from the model of content based routing (CBR, combined with several advanced techniques such as Multicast, multiple path routing, Genetic algorithm to increase the data rate, and data encryption to ensure information security. Fuzzy logic is a logical field study evaluating the accuracy of the results based on the approximation of the components involved, make decisions based on many factors relative accuracy based on experimental or mathematical proof. This article presents some techniques to support multiple path routing from one network node to a set of nodes with guaranteed quality of service. By using these techniques can decrease the network load, congestion, use network resources efficiently.

Airspace Technology Demonstration 3 (ATD-3): Dynamic Weather Routes (DWR) Technology Transfer Document Summary Version 1.0

Science.gov (United States)

Sheth, Kapil; Wang, Easter Mayan Chan

2016-01-01

Airspace Technology Demonstration #3 (ATD-3) is part of NASA's Airspace Operations and Safety Program (AOSP) - specifically, its Airspace Technology Demonstrations (ATD) Project. ATD-3 is a multiyear research and development effort which proposes to develop and demonstrate automation technologies and operating concepts that enable air navigation service providers and airspace users to continuously assess weather, winds, traffic, and other information to identify, evaluate, and implement workable opportunities for flight plan route corrections that can result in significant flight time and fuel savings in en route airspace. In order to ensure that the products of this tech-transfer are relevant and useful, NASA has created strong partnerships with the FAA and key industry stakeholders. This summary document and accompanying technology artifacts satisfy the first of three Research Transition Products (RTPs) defined in the Applied Traffic Flow Management (ATFM) Research Transition Team (RTT) Plan. This transfer consists of NASA's legacy Dynamic Weather Routes (DWR) work for efficient routing for en-route weather avoidance. DWR is a ground-based trajectory automation system that continuously and automatically analyzes active airborne aircraft in en route airspace to identify opportunities for simple corrections to flight plan routes that can save significant flying time, at least five minutes wind-corrected, while avoiding weather and considering traffic conflicts, airspace sector congestion, special use airspace, and FAA routing restrictions. The key benefit of the DWR concept is to let automation continuously and automatically analyze active flights to find those where simple route corrections can save significant time and fuel. Operators are busy during weather events. It is more effective to let automation find the opportunities for high-value route corrections.

Capacitated vehicle-routing problem model for scheduled solid waste collection and route optimization using PSO algorithm.

Science.gov (United States)

Hannan, M A; Akhtar, Mahmuda; Begum, R A; Basri, H; Hussain, A; Scavino, Edgar

2018-01-01

Waste collection widely depends on the route optimization problem that involves a large amount of expenditure in terms of capital, labor, and variable operational costs. Thus, the more waste collection route is optimized, the more reduction in different costs and environmental effect will be. This study proposes a modified particle swarm optimization (PSO) algorithm in a capacitated vehicle-routing problem (CVRP) model to determine the best waste collection and route optimization solutions. In this study, threshold waste level (TWL) and scheduling concepts are applied in the PSO-based CVRP model under different datasets. The obtained results from different datasets show that the proposed algorithmic CVRP model provides the best waste collection and route optimization in terms of travel distance, total waste, waste collection efficiency, and tightness at 70-75% of TWL. The obtained results for 1 week scheduling show that 70% of TWL performs better than all node consideration in terms of collected waste, distance, tightness, efficiency, fuel consumption, and cost. The proposed optimized model can serve as a valuable tool for waste collection and route optimization toward reducing socioeconomic and environmental impacts. Copyright © 2017 Elsevier Ltd. All rights reserved.

Route selection issues for NWPA shipments

International Nuclear Information System (INIS)

Hill, C.V.; Harrison, I.G.

1993-01-01

Questions surrounding the designation of routes for the movement of spent nuclear fuel (SNF) and high-level radioactive waste (HLW) by the Office of Civilian Radioactive Waste Management (OCRWM) have broad implications. Federal regulations prescribe rules to be applied in the selection of highway routes. In most cases, these rules will lead to a clear selection of one route between an origin and destination point. However, in other cases, strict application of the regulations does not result in a clear choice of a preferred route. The regulations also provide discretion to State governments and carriers to select alternative routes to enhance the safety of the shipment. Railroad shipments of radioactive materials are not subject to Federal routing regulations. Since the railroads operate on private property, it has been assumed that they know the best way to move freight on their system. This discretion, while desirable for addressing unique local safety concerns or for responding to temporary safety concerns such as road problems, weather conditions, or construction areas, leads to significant opportunity for misunderstandings and uneasiness on the part of local residents

Routing Protocols for Underwater Wireless Sensor Networks: Taxonomy, Research Challenges, Routing Strategies and Future Directions.

Science.gov (United States)

Khan, Anwar; Ali, Ihsan; Ghani, Abdullah; Khan, Nawsher; Alsaqer, Mohammed; Rahman, Atiq Ur; Mahmood, Hasan

2018-05-18

Recent research in underwater wireless sensor networks (UWSNs) has gained the attention of researchers in academia and industry for a number of applications. They include disaster and earthquake prediction, water quality and environment monitoring, leakage and mine detection, military surveillance and underwater navigation. However, the aquatic medium is associated with a number of limitations and challenges: long multipath delay, high interference and noise, harsh environment, low bandwidth and limited battery life of the sensor nodes. These challenges demand research techniques and strategies to be overcome in an efficient and effective fashion. The design of routing protocols for UWSNs is one of the promising solutions to cope with these challenges. This paper presents a survey of the routing protocols for UWSNs. For the ease of description, the addressed routing protocols are classified into two groups: localization-based and localization-free protocols. These groups are further subdivided according to the problems they address or the major parameters they consider during routing. Unlike the existing surveys, this survey considers only the latest and state-of-the-art routing protocols. In addition, every protocol is described in terms of its routing strategy and the problem it addresses and solves. The merit(s) of each protocol is (are) highlighted along with the cost. A description of the protocols in this fashion has a number of advantages for researchers, as compared to the existing surveys. Firstly, the description of the routing strategy of each protocol makes its routing operation easily understandable. Secondly, the demerit(s) of a protocol provides (provide) insight into overcoming its flaw(s) in future investigation. This, in turn, leads to the foundation of new protocols that are more intelligent, robust and efficient with respect to the desired parameters. Thirdly, a protocol can be selected for the appropriate application based on its described

The QKD network: model and routing scheme

Science.gov (United States)

Yang, Chao; Zhang, Hongqi; Su, Jinhai

2017-11-01

Quantum key distribution (QKD) technology can establish unconditional secure keys between two communicating parties. Although this technology has some inherent constraints, such as the distance and point-to-point mode limits, building a QKD network with multiple point-to-point QKD devices can overcome these constraints. Considering the development level of current technology, the trust relaying QKD network is the first choice to build a practical QKD network. However, the previous research didn't address a routing method on the trust relaying QKD network in detail. This paper focuses on the routing issues, builds a model of the trust relaying QKD network for easily analysing and understanding this network, and proposes a dynamical routing scheme for this network. From the viewpoint of designing a dynamical routing scheme in classical network, the proposed scheme consists of three components: a Hello protocol helping share the network topology information, a routing algorithm to select a set of suitable paths and establish the routing table and a link state update mechanism helping keep the routing table newly. Experiments and evaluation demonstrates the validity and effectiveness of the proposed routing scheme.

Environmental factors along the Northern Sea Route

International Nuclear Information System (INIS)

Fjeld, P.E.

1993-01-01

The Northern Sea Route runs ca 5,600 nautical miles across the top of Russia from Murmansk to Vladivostok, and includes half of the Arctic basin. An environmental impact assessment is needed for this route because of the potential for commercial shipping to disturb the vulnerable Arctic environment along the route. For example, Russian development of oil and gas resources in the area served by the route is expected to rise dramatically in the near future. Drilling in the route area offshore has already begun, and potential blowouts or tanker spills are of concern. A pilot study on the environment along this route was conducted in 1990/91, focusing on a study of the literature and communications with Russian scientists working on Arctic ecology. Existing data seem to be insufficient and generally only cover the westernmost and easternmost parts of the route. A five-year research plan is proposed to provide an inventory of Arctic species in the route area and levels of contaminants present, to assess the environmental sensitivity of the area, and analyze impacts that increased shipping might have on the environment. Protection measures will also be suggested. 1 fig

Microstructural evolution and rheological properties of AA6063 alloy produced by semisolid processing (SIMA and MHD)

International Nuclear Information System (INIS)

Bustos, O.; Leiva, R.; Sanchez, C.; Ordonez, S.; Carvajal, L.; Mannheim, R.

2007-01-01

In this work the rheological behaviour and the microstructural evolution of alloy AA6063 submitted to two different processing routes were studied: cold deformation and partial fusion (SIMA process) and magneto hydrodynamic stirring during its solidification (MHD process). The microstructural evolution during the isothermal holding was studied to verify if the Ost wald ripening mechanisms, classic growth and coalescence, are applicable to alloys made by these processing routes. The rheological properties were evaluated using a compression rheometer with parallel plates and digital capture of position and time data. Compression tests were made in short cylinders extracted from ingots that showed: a dendritic microstructure typical of as cast material, a typical microstructure of cold deformed material and a microstructure of materials obtained by MHD process. It was found that a globular microstructure has a typical behaviour of a fluid when being formed in semisolid state, contrary to the behaviour of the as cast dendritic microstructure. In addition, the mechanisms that operate in the microstructural evolution during the isothermal holdings were verified, through metallographic analysis. (Author) 29 refs

The Evolution of Inquiry Activities in the Akamai Observatory Short Course, 2004-2009

Science.gov (United States)

Rice, E. L.; McElwain, M.; Sonnett, S.; Rafelski, M.

2010-12-01

The Akamai Observatory Short Course (AOSC) is a five-day course of activities designed to prepare college students majoring in science, technology, engineering, and mathematics (STEM) fields for internships at observatories on the Big Island of Hawai'i. The design and implementation of inquiry-based activities in the AOSC have evolved considerably over the six years of the course. The content goals have always focused on the basic understanding of light and optics necessary to understand telescopes, but the scientific process goals gradually evolved to reflect the increasingly recognized importance of engineering design skills for successful observatory internships. In 2004 the inquiry-based activities were limited to one well-established Color, Light, and Spectra activity. In subsequent years more activities were customized and expanded upon to reflect the learners' diverse academic backgrounds, the developing goals of the short course, and feedback from internship hosts. The most recent inquiry, the Design and Build a Telescope activity, engaged students in designing and building a simple telescope, emphasizing science and engineering process skills in addition to science content. This activity was influenced by the Mission Design activity, added in 2006, that incorporated the application of inquiry-based learning to the engineering design process and allowed students to draw upon their diverse prior knowledge and experience. In this paper we describe the inquiry-based activities in the AOSC in the context of its year-to-year evolution, including the conceptual and pragmatic changes to the short course that influenced the evolution.

CAN Tree Routing for Content-Addressable Network

Directory of Open Access Journals (Sweden)

Zhongtao LI

2014-01-01

Full Text Available We propose a novel topology to improve the routing performance of Content- Addressable Network overlays while minimizing the maintenance overhead during nodes churn. The key idea of our approach is to establish a P2P tree structure (CAN tree by means of equipping each node with a few long links towards some distant nodes. The long links enhance routing flexibility and robustness against failures. Nodes automatically adapt routing table to cope with network change. The routing complexity is O(log n, which is much better than a uniform greedy routing, while each node maintains two long links in average.

A functional near-infrared spectroscopy study of lexical decision task supports the dual route model and the phonological deficit theory of dyslexia.

Science.gov (United States)

Sela, Itamar; Izzetoglu, Meltem; Izzetoglu, Kurtulus; Onaral, Banu

2014-01-01

The dual route model (DRM) of reading suggests two routes of reading development: the phonological and the orthographic routes. It was proposed that although the two routes are active in the process of reading; the first is more involved at the initial stages of reading acquisition, whereas the latter needs more reading training to mature. A number of studies have shown that deficient phonological processing is a core deficit in developmental dyslexia. According to the DRM, when the Lexical Decision Task (LDT) is performed, the orthographic route should also be involved when decoding words, whereas it is clear that when decoding pseudowords the phonological route should be activated. Previous functional near-infrared spectroscopy (fNIR) studies have suggested that the upper left frontal lobe is involved in decision making in the LDT. The current study used fNIR to compare left frontal lobe activity during LDT performance among three reading-level groups: 12-year-old children, young adult dyslexic readers, and young adult typical readers. Compared to typical readers, the children demonstrated lower activity under the word condition only, whereas the dyslexic readers showed lower activity under the pseudoword condition only. The results provide evidence for upper left frontal lobe involvement in LDT and support the DRM and the phonological deficit theory of dyslexia.

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.

Route planning algorithms: Planific@ Project

Directory of Open Access Journals (Sweden)

Gonzalo Martín Ortega

2009-12-01

Full Text Available Planific@ is a route planning project for the city of Madrid (Spain. Its main aim is to develop an intelligence system capable of routing people from one place in the city to any other using the public transport. In order to do this, it is necessary to take into account such things as: time, traffic, user preferences, etc. Before beginning to design the project is necessary to make a comprehensive study of the variety of main known route planning algorithms suitable to be used in this project.

MAGNETIC FLUX TRANSPORT AND THE LONG-TERM EVOLUTION OF SOLAR ACTIVE REGIONS

International Nuclear Information System (INIS)

Ugarte-Urra, Ignacio; Upton, Lisa; Warren, Harry P.; Hathaway, David H.

2015-01-01

With multiple vantage points around the Sun, Solar Terrestrial Relations Observatory (STEREO) and Solar Dynamics Observatory imaging observations provide a unique opportunity to view the solar surface continuously. We use He ii 304 Å data from these observatories to isolate and track ten active regions and study their long-term evolution. We find that active regions typically follow a standard pattern of emergence over several days followed by a slower decay that is proportional in time to the peak intensity in the region. Since STEREO does not make direct observations of the magnetic field, we employ a flux-luminosity relationship to infer the total unsigned magnetic flux evolution. To investigate this magnetic flux decay over several rotations we use a surface flux transport model, the Advective Flux Transport model, that simulates convective flows using a time-varying velocity field and find that the model provides realistic predictions when information about the active region's magnetic field strength and distribution at peak flux is available. Finally, we illustrate how 304 Å images can be used as a proxy for magnetic flux measurements when magnetic field data is not accessible

Active galactic nuclei and their role in galaxy evolution : The infrared perspective

NARCIS (Netherlands)

Caputi, K. I.

The remarkable progress made in infrared (IR) astronomical instruments over the last 10-15 years has radically changed our vision of the extragalactic IR sky, and overall understanding of galaxy evolution. In particular, this has been the case for the study of active galactic nuclei (AGN), for which

Comparison of routing metrics for wireless mesh networks

CSIR Research Space (South Africa)

Nxumalo, SL

2011-09-01

Full Text Available in each and every relay node so as to find the next hop for the packet. A routing metric is simply a measure used for selecting the best path, used by a routing protocol. Figure 2 shows the relationship between a routing protocol and the routing... on its QoS-awareness level. The routing metrics that considered QoS the most were selected from each group. This section discusses the four routing metrics that were compared in this paper, which are: hop count (HOP), expected transmission count (ETX...

Mesoporous Ruthenium/Ruthenium Oxide Thin Films: Active Electrocatalysts for the Oxygen Evolution Reaction

DEFF Research Database (Denmark)

Kibsgaard, Jakob; Hellstern, Thomas R.; Choi, Shin-Jung

2017-01-01

We report the first synthesis of a fully contiguous large area supported thin film of highly ordered mesoporous Ru and RuO2 and investigate the electrocatalytic properties towards the oxygen evolution reaction (OER). We find that the nanoscale porous network of these catalysts provides significant...... enhancements in geometric OER activity without any loss in specific activity. This work demonstrates a strategy for engineering materials at the nanoscale that can simultaneously decrease precious metal loading and increase electrode activity....

The Silk Route from Land to Sea

Directory of Open Access Journals (Sweden)

Jack Weatherford

2018-04-01

Full Text Available The Silk Route reached its historic and economic apogee under the Mongol Empire (1207–1368, as a direct result of the policies of Chinggis Khan (Genghis Khan and his successors. Because the land network proved inefficient for the amount of goods needing transport from one part of the empire to another, the Mongols expanded the Silk Route to ocean shipping and thus created the first Maritime Silk Route. The sea traffic initially expanded the land routes but soon strangled them. With the expansion of the Maritime Silk Route through the fourteenth century, the land connections reverted to local networks and lost their global importance.

Decision Support from Genetic Algorithms for Ship Collision Avoidance Route Planning and Alerts

Science.gov (United States)

Tsou, Ming-Cheng; Kao, Sheng-Long; Su, Chien-Min

When an officer of the watch (OOW) faces complicated marine traffic, a suitable decision support tool could be employed in support of collision avoidance decisions, to reduce the burden and greatly improve the safety of marine traffic. Decisions on routes to avoid collisions could also consider economy as well as safety. Through simulating the biological evolution model, this research adopts the genetic algorithm used in artificial intelligence to find a theoretically safety-critical recommendation for the shortest route of collision avoidance from an economic viewpoint, combining the international regulations for preventing collisions at sea (COLREGS) and the safety domain of a ship. Based on this recommendation, an optimal safe avoidance turning angle, navigation restoration time and navigational restoration angle will also be provided. A Geographic Information System (GIS) will be used as the platform for display and operation. In order to achieve advance notice of alerts and due preparation for collision avoidance, a Vessel Traffic Services (VTS) operator and the OOW can use this system as a reference to assess collision avoidance at present location.

Perception bias in route choice

NARCIS (Netherlands)

Vreeswijk, Jacob Dirk; Thomas, Tom; van Berkum, Eric C.; van Arem, Bart

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

A model to improve the routing performance of Cognitive Radio Wireless Mesh Networks

Directory of Open Access Journals (Sweden)

Lesiba Morries Kola

2017-12-01

Full Text Available The increasing demand for broadband wireless technologies has led to the scarcity, inefficient utilization, and underutilization of the spectrum. The Cognitive Radio (CR technology has emerged as the promising solution which improves the utilization of the spectrum. However, routing is a challenge due to the dynamic nature of the CR networks. The link quality varies in space and time as nodes join and leave the network. The network connectivity is intermittent due to node mobility and the activities of the primary user. The spectrum aware, spectrum agile, and interference aware routing protocols are vital for the sturdiness of the network and efficient utilization of the resources. We propose an interference aware, spectrum aware, and agile extended Weighted Cumulative Expected Transmission Time (xWCETT routing protocol. The protocol integrates the features of the Ad-hoc On-demand Distance Vector (AODV and the weighted cumulative expected transmission time (WCETT routing protocols. The xWCETT was simulated using the Network Simulator 2 and its performance compared with the AODV and the WCETT routing protocols. The xWCETT was evaluated with respect to quality of service related metrics and the results show that it outperformed the AODV and WCETT routing protocols.

User habits and multimodal route planning

Directory of Open Access Journals (Sweden)

Géza Katona

2017-10-01

Full Text Available The results of route planning researches are monitored by logistic and automotive industries. The economic aspects of the cost saving are in the focus of the attention. An optimal route could cause time or fuel savings. An effective driving or an optimal route is a good basis to achieve an economical aim. Moreover the spread of new automotive solutions especially in case of electric cars the optimisation has particular significance regarding the limited battery storage. Additionally the autonomous car development could not be neglected. As a result the society could expect safer roads, better space usage and effective resource management. Nevertheless the requirements of users are extremely diverse, which is not negligible. Supporting these aims, in this paper the connection between the multimodal route planning and the user requirements are investigated. The examination is focused to a sensitivity analysis and a survey to evaluate the data and support the settings of a user habit effect to the final route.

Routing Data Authentication in Wireless Networks; TOPICAL

International Nuclear Information System (INIS)

TORGERSON, MARK D.; VAN LEEUWEN, BRIAN P.

2001-01-01

In this paper, we discuss several specific threats directed at the routing data of an ad hoc network. We address security issues that arise from wrapping authentication mechanisms around ad hoc routing data. We show that this bolt-on approach to security may make certain attacks more difficult, but still leaves the network routing data vulnerable. We also show that under a certain adversarial model, most existing routing protocols cannot be secured with the aid of digital signatures

Literary Routes: Contributions to Natural/Cultural Heritage Tourism. How landscape transforms literature and tourism

Directory of Open Access Journals (Sweden)

Rosalinda Ruiz Scarfuto

2013-12-01

Full Text Available Literary routes inspired by landscapes is a topic where cultural and natural routes merge to form an added value of heritage that is greater than either one standing alone.  Landscape is traditionally defined as a consequence of transformations by humans, and its scope rarely takes into account how nature has inspired literature to advance the “intellectual development of humankind,” hence transforming heritage.  Literary routes paralleling transhumance routes embraced by the Sami, First Nations, or Spanish shepherds (full of landscapes, seascapes, and riverscapes, can actively transmit traditional technologies, biodiversity, and cosmic philosophy for the betterment of humankind; for example, the depth of literary heritage inspired by landscapes enhances our collective memory through a network of archives (libraries, collections.  The continuous dissemination of this literature traversing borders, language barriers, and time periods has stimulated literary routes to emerge as a function of moving the experience from an intangible heritage based on imaginary landscapes to a tangible sensory experience in situ following a plot, author’s life, or a myth. Literary routes respond to the demand of the growing target travellers, who are more literate and active today than in the past. They are excited followers of their favourite writers, and seek ways to be in contact with them. Now it is time to rekindle the collective memory, expand the literary dimension, and offer a sensorial in situ experience by adding a literary link. For instance, myths of the Ohlone Nation based near a California wetlands use the symbolic coyote as the intermediary to teach humans how to live in harmony with their ecosystem; or in Spain, Arcipreste de Hita’s novel El Libro de Buen Amor (1330 describes traditions and gastronomy as it criss-crosses the Guadarrama mountains, alongside the Poets’ Route that includes international Nobel prize winners in literature

The Time Window Vehicle Routing Problem Considering Closed Route

Science.gov (United States)

Irsa Syahputri, Nenna; Mawengkang, Herman

2017-12-01

The Vehicle Routing Problem (VRP) determines the optimal set of routes used by a fleet of vehicles to serve a given set of customers on a predefined graph; the objective is to minimize the total travel cost (related to the travel times or distances) and operational cost (related to the number of vehicles used). In this paper we study a variant of the predefined graph: given a weighted graph G and vertices a and b, and given a set X of closed paths in G, find the minimum total travel cost of a-b path P such that no path in X is a subpath of P. Path P is allowed to repeat vertices and edges. We use integer programming model to describe the problem. A feasible neighbourhood approach is proposed to solve the model

A Functional Near-Infrared Spectroscopy Study of Lexical Decision Task Supports the Dual Route Model and the Phonological Deficit Theory of Dyslexia

Science.gov (United States)

Sela, Itamar; Izzetoglu, Meltem; Izzetoglu, Kurtulus; Onaral, Banu

2014-01-01

The dual route model (DRM) of reading suggests two routes of reading development: the phonological and the orthographic routes. It was proposed that although the two routes are active in the process of reading; the first is more involved at the initial stages of reading acquisition, whereas the latter needs more reading training to mature. A…

Evolution of public relations in the activity of organizations of ukrainian socio-cultural sphere

Directory of Open Access Journals (Sweden)

Євгенія Олегівна Кияниця

2015-04-01

Full Text Available The article traces the evolution of public relations in various fields of life including socio-cultural and found creative and social potential of this activity. Analysis of historical experience of using the PR-technologies in the field of sociocultural institutions promotes understanding of importance of this activity for the efficient work of organizations of this sphere

Balancing activity, stability and conductivity of nanoporous core-shell iridium/iridium oxide oxygen evolution catalysts

Energy Technology Data Exchange (ETDEWEB)

Kim, Yong-Tae; Lopes, Pietro Papa; Park, Shin-Ae; Lee, A-Yeong; Lim, Jinkyu; Lee, Hyunjoo; Back, Seoin; Jung, Yousung; Danilovic, Nemanja; Stamenkovic, Vojislav; Erlebacher, Jonah; Snyder, Joshua; Markovic, Nenad M.

2017-11-13

The selection of oxide materials for catalyzing the Oxygen Evolution Reaction in acid-based electrolyzers must be guided by the proper balance between activity, stability and conductivity – a challenging mission of great importance for delivering affordable and environmentally friendly hydrogen. Here we report that the highly conductive nanoporous architecture of an iridium oxide shell on a metallic iridium core, formed through the fast dealloying of osmium from an Ir25Os75 alloy, exhibits an exceptional balance between oxygen evolution activity and stability as quantified by the Activity-Stability FactorASF. Based on this metric, the nanoporous Ir/IrO2 morphology of dealloyed Ir25Os75 shows a factor of ~30 improvement ASFrelative to conventional Ir-based oxide materials and a ~8 times improvement over dealloyed Ir25Os75 nanoparticles due to optimized stability and conductivity, respectively. We propose that the Activity-Stability FactorASF is the key “metric” for determining the technological relevance of oxide-based anodic water electrolyzer catalysts.

Microstructural evolution and tensile mechanical properties of thixoformed AZ91D magnesium alloy with the addition of yttrium

International Nuclear Information System (INIS)

Zhao Zude; Chen Qiang; Kang Feng; Shu Dayu

2009-01-01

The microstructure evolution of AZ91D magnesium alloy in the semi-solid state has been proposed or reported in previous literature. However, no detailed investigation has been conducted regarding the relationship between the microstructure and tensile mechanical properties of the thixoformed AZ91D magnesium alloy. In this paper, the microstructure of AZ91D alloy with the addition of yttrium was produced by the semi-solid thermal transformation (SSTT) route and the strain-induced melt activation (SIMA) route, respectively. Isothermal holding experiments investigated grain coarsening and the degree of spheroidization as a function of holding time in the semi-solid state. The SSTT route and the SIMA route were used to obtain the semi-solid feedstock for thixoforming. The results show that solid particles of the SSTT alloy are spheroidized to some extent but the previous irregular shape is still obvious in some of them. While the SIMA alloy exhibits ideal, fine microstructure, in which completely spheroidized solid particles contain little entrapped liquid. The microstructure of the SSTT alloy is less spheroidized compared with the SIMA alloy under the similar isothermal holding condition. As the holding time increases, the mean solid particle size of the SSTT alloy decreases initially, then increases, while the mean solid particle size of the SIMA alloy increases monotonously at 560 deg. C. Compared with the SSTT alloy, the SIMA alloy obtains finer grains under the similar isothermal holding condition. The mechanical properties of the thixoformed AZ91D alloy with the addition of yttrium produced by the SIMA route are better than those of the thixoformed alloy produced by the SSTT route. The ultimate tensile strength, yield strength and elongation for the thixoformed alloy produced by the SIMA route are 303.1 MPa, 147.6 MPa and 13.27%, respectively. The tensile properties for the AZ91D alloy with the addition of yttrium thixoformed from starting material produced by

Cost-Effective Encryption-Based Autonomous Routing Protocol for Efficient and Secure Wireless Sensor Networks.

Science.gov (United States)

Saleem, Kashif; Derhab, Abdelouahid; Orgun, Mehmet A; Al-Muhtadi, Jalal; Rodrigues, Joel J P C; Khalil, Mohammed Sayim; Ali Ahmed, Adel

2016-03-31

The deployment of intelligent remote surveillance systems depends on wireless sensor networks (WSNs) composed of various miniature resource-constrained wireless sensor nodes. The development of routing protocols for WSNs is a major challenge because of their severe resource constraints, ad hoc topology and dynamic nature. Among those proposed routing protocols, the biology-inspired self-organized secure autonomous routing protocol (BIOSARP) involves an artificial immune system (AIS) that requires a certain amount of time to build up knowledge of neighboring nodes. The AIS algorithm uses this knowledge to distinguish between self and non-self neighboring nodes. The knowledge-building phase is a critical period in the WSN lifespan and requires active security measures. This paper proposes an enhanced BIOSARP (E-BIOSARP) that incorporates a random key encryption mechanism in a cost-effective manner to provide active security measures in WSNs. A detailed description of E-BIOSARP is presented, followed by an extensive security and performance analysis to demonstrate its efficiency. A scenario with E-BIOSARP is implemented in network simulator 2 (ns-2) and is populated with malicious nodes for analysis. Furthermore, E-BIOSARP is compared with state-of-the-art secure routing protocols in terms of processing time, delivery ratio, energy consumption, and packet overhead. The findings show that the proposed mechanism can efficiently protect WSNs from selective forwarding, brute-force or exhaustive key search, spoofing, eavesdropping, replaying or altering of routing information, cloning, acknowledgment spoofing, HELLO flood attacks, and Sybil attacks.

Cost-Effective Encryption-Based Autonomous Routing Protocol for Efficient and Secure Wireless Sensor Networks

Science.gov (United States)

Saleem, Kashif; Derhab, Abdelouahid; Orgun, Mehmet A.; Al-Muhtadi, Jalal; Rodrigues, Joel J. P. C.; Khalil, Mohammed Sayim; Ali Ahmed, Adel

2016-01-01

The deployment of intelligent remote surveillance systems depends on wireless sensor networks (WSNs) composed of various miniature resource-constrained wireless sensor nodes. The development of routing protocols for WSNs is a major challenge because of their severe resource constraints, ad hoc topology and dynamic nature. Among those proposed routing protocols, the biology-inspired self-organized secure autonomous routing protocol (BIOSARP) involves an artificial immune system (AIS) that requires a certain amount of time to build up knowledge of neighboring nodes. The AIS algorithm uses this knowledge to distinguish between self and non-self neighboring nodes. The knowledge-building phase is a critical period in the WSN lifespan and requires active security measures. This paper proposes an enhanced BIOSARP (E-BIOSARP) that incorporates a random key encryption mechanism in a cost-effective manner to provide active security measures in WSNs. A detailed description of E-BIOSARP is presented, followed by an extensive security and performance analysis to demonstrate its efficiency. A scenario with E-BIOSARP is implemented in network simulator 2 (ns-2) and is populated with malicious nodes for analysis. Furthermore, E-BIOSARP is compared with state-of-the-art secure routing protocols in terms of processing time, delivery ratio, energy consumption, and packet overhead. The findings show that the proposed mechanism can efficiently protect WSNs from selective forwarding, brute-force or exhaustive key search, spoofing, eavesdropping, replaying or altering of routing information, cloning, acknowledgment spoofing, HELLO flood attacks, and Sybil attacks. PMID:27043572

Cost-Effective Encryption-Based Autonomous Routing Protocol for Efficient and Secure Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Kashif Saleem

2016-03-01

Full Text Available The deployment of intelligent remote surveillance systems depends on wireless sensor networks (WSNs composed of various miniature resource-constrained wireless sensor nodes. The development of routing protocols for WSNs is a major challenge because of their severe resource constraints, ad hoc topology and dynamic nature. Among those proposed routing protocols, the biology-inspired self-organized secure autonomous routing protocol (BIOSARP involves an artificial immune system (AIS that requires a certain amount of time to build up knowledge of neighboring nodes. The AIS algorithm uses this knowledge to distinguish between self and non-self neighboring nodes. The knowledge-building phase is a critical period in the WSN lifespan and requires active security measures. This paper proposes an enhanced BIOSARP (E-BIOSARP that incorporates a random key encryption mechanism in a cost-effective manner to provide active security measures in WSNs. A detailed description of E-BIOSARP is presented, followed by an extensive security and performance analysis to demonstrate its efficiency. A scenario with E-BIOSARP is implemented in network simulator 2 (ns-2 and is populated with malicious nodes for analysis. Furthermore, E-BIOSARP is compared with state-of-the-art secure routing protocols in terms of processing time, delivery ratio, energy consumption, and packet overhead. The findings show that the proposed mechanism can efficiently protect WSNs from selective forwarding, brute-force or exhaustive key search, spoofing, eavesdropping, replaying or altering of routing information, cloning, acknowledgment spoofing, HELLO flood attacks, and Sybil attacks.

A Machine Learning Concept for DTN Routing

Science.gov (United States)

Dudukovich, Rachel; Hylton, Alan; Papachristou, Christos

2017-01-01

This paper discusses the concept and architecture of a machine learning based router for delay tolerant space networks. The techniques of reinforcement learning and Bayesian learning are used to supplement the routing decisions of the popular Contact Graph Routing algorithm. An introduction to the concepts of Contact Graph Routing, Q-routing and Naive Bayes classification are given. The development of an architecture for a cross-layer feedback framework for DTN (Delay-Tolerant Networking) protocols is discussed. Finally, initial simulation setup and results are given.

Kinetic modeling of the polymer-derived ceramics route: investigation of the thermal decomposition kinetics of poly[B-(methylamino)borazine] precursors into boron nitride.

Science.gov (United States)

Bernard, Samuel; Fiaty, Koffi; Cornu, David; Miele, Philippe; Laurent, Pierre

2006-05-11

A complete kinetic modeling of the polymer-derived ceramics (PDCs) route is achieved for the first time through the investigation of the solid-state decomposition of a typical melt-spinnable poly[B-(methylamino)borazine] into boron nitride fibers at various heating rates. Through the use of the Lorentz fitting approach, it is shown that the two-step weight loss associated with the polymer-to-ceramic conversion is governed by a complex interplay of five diffusion-type transport mechanisms that are independent of the applied heating schedule. The application of the Friedman method to dynamic thermogravimetry data yields Ea and ln A values that are seen to increase with the extent of the ceramic conversion from region one (Ea = 38.73 kJ mol(-1)) to region five (Ea = 146.64 kJ mol(-1)). This fact indicates that both the mechanisms within those regions are parallel routes to the formation of the final solid-state material and their complexity increases with the conversion progress. The cross-linking process (first weight loss) of the polymer is governed by three dependent poorly energetic mechanisms. The first weight loss is activated by ammonolysis reactions that provide a modified polymer capable of undergoing condensation reactions in regions two and three to yield a highly cross-linked polymer. A large evolution of methylamine is identified during this process. Mineralization (region four) and ceramization (region five) steps are represented by two highly energetic multistep mechanisms. The mineralization step is associated with a large evolution of methylamine and occurs during the transition between the cross-linking and ceramization processes through the cleavage of the inter-ring B-N bonds. Ceramization represents the end of the polymer-to-ceramic conversion in which the planar consolidation of BN hexagons occurs through complex structural rearrangements of the borazine units (cleavage of the intraring B-N bonds) accompanied with an ammonia evolution. Finally

Short-term radon activity concentration changes along the Underground Educational Tourist Route in the Old Uranium Mine in Kletno (Sudety Mts., SW Poland).

Science.gov (United States)

Fijałkowska-Lichwa, Lidia

2014-09-01

Short-term (222)Rn activity concentration changes along the Underground Educational Tourist Route in the Old Uranium Mine in Kletno were studied, based on continuous measurements conducted between 16 May 2008 and 15 May 2010. The results were analysed in the context of numbers of visitors arriving at the facility in particular seasons and the time per day spent inside by staff and visitors. This choice was based on partially published earlier findings (Fijałkowska-Lichwa and Przylibski, 2011). Results for the year 2009 were analysed in depth, because it is the only period of observation covering a full calendar year. The year 2009 was also chosen for detailed analysis of short-term radon concentration changes, because in each period of this year (hour, month, season) fluctuations of noted values were the most visible. Attention has been paid to three crucial issues linked to the occurrence and behaviour of radon and to the radiological protection of workers and visitors at the tourist route in Kletno. The object of study is a complex of workings in a former uranium mine situated within a metamorphic rock complex in the most radon-prone area in Poland. The facility has been equipped with a mechanical ventilation system, which is turned on after the closing time and at the end of the working day for the visitor service staff, i.e. after 6 p.m. Short-term radon activity concentration changes along the Underground Educational Tourist Route in the Old Uranium Mine in Kletno are related to the activity of the facility's mechanical ventilation. Its inactivity in the daytime results in the fact that the highest values of (222)Rn activity concentration are observed at the time when the facility is open to visitors, i.e. between 10 a.m. and 6 p.m. The improper usage of the mechanical ventilation system is responsible for the extremely unfavourable working conditions, which persist in the facility for practically all year. The absence of appropriate radiological protection

Oral transmission as a route of infection for viral haemorrhagic septicaemia virus in rainbow trout, Oncorhynchus mykiss (Walbaum)

DEFF Research Database (Denmark)

Schönherz, Anna Amanda; Hansen, M. H. H.; Jørgensen, H. B. H.

2012-01-01

replication in stomach and kidney tissue was detected through bioluminescence activity of luciferase and qRT‐PCR. Replication was detected in both tissues, irrespective of transmission route. Replication patterns, however, differed among transmission routes. In trout infected through oral transmission...

Warehouse order-picking process. Order-picker routing problem

Directory of Open Access Journals (Sweden)

E. V. Korobkov

2015-01-01

Full Text Available This article continues “Warehouse order-picking process” cycle and describes order-picker routing sub-problem of a warehouse order-picking process. It draws analogies between the orderpickers’ routing problem and traveling salesman’s problem, shows differences between the standard problem statement of a traveling salesman and routing problem of warehouse orderpickers, and gives the particular Steiner’s problem statement of a traveling salesman.Warehouse layout with a typical order is represented by a graph, with some its vertices corresponding to mandatory order-picker’s visits and some other ones being noncompulsory. The paper describes an optimal Ratliff-Rosenthal algorithm to solve order-picker’s routing problem for the single-block warehouses, i.e. warehouses with only two crossing aisles, defines seven equivalent classes of partial routing sub-graphs and five transitions used to have an optimal routing sub-graph of a order-picker. An extension of optimal Ratliff-Rosenthal order-picker routing algorithm for multi-block warehouses is presented and also reasons for using the routing heuristics instead of exact optimal algorithms are given. The paper offers algorithmic description of the following seven routing heuristics: S-shaped, return, midpoint, largest gap, aisle-by-aisle, composite, and combined as well as modification of combined heuristics. The comparison of orderpicker routing heuristics for one- and two-block warehouses is to be described in the next article of the “Warehouse order-picking process” cycle.

En Route Descent Advisor Multi-Sector Planning Using Active and Provisional Controller Plans

Science.gov (United States)

Vivona, Robert; Green, Steven

2003-01-01

As decision support tools are developed to support controllers in complex air traffic control environments, new approaches to maintaining situation awareness and managing traffic planning must be developed to handle the ever-increasing amounts of alerting and advisory data. Within high-density metering and other environments where flight path changes are the rule, not the exception, and where interactions between these changes are required, current trial planning approaches are limited by potential increases in workload. The Enroute Descent Advisor (EDA) is a set of decision support tool capabilities for managing high-density en route traffic subject to metering restrictions. The EDA system s novel approach builds aircraft plans from combinations of user intent data and builds controller plans from combinations of aircraft plans to effectively maintain situation awareness during traffic planning. By maintaining both active (current) and provisional (proposed) controller plans, EDA supports controllers in coordinated traffic planning both within and between sectors. Ultimately, EDA s multi-sector planning approach will facilitate a transition from current sector-oriented operations to a new trajectory-oriented paradigm, enabling new levels of efficiency and collaboration in air traffic control.

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...

Stochastic vehicle routing with recourse

DEFF Research Database (Denmark)

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

2012-01-01

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...

Integer Optimization Model for a Logistic System based on Location-Routing Considering Distance and Chosen Route

Science.gov (United States)

Mulyasari, Joni; Mawengkang, Herman; Efendi, Syahril

2018-02-01

In a distribution network it is important to decide the locations of facilities that impacts not only the profitability of an organization but the ability to serve customers.Generally the location-routing problem is to minimize the overall cost by simultaneously selecting a subset of candidate facilities and constructing a set of delivery routes that satisfy some restrictions. In this paper we impose restriction on the route that should be passed for delivery. We use integer programming model to describe the problem. A feasible neighbourhood search is proposed to solve the result model.

Synthesis of sulfonated porous carbon nanospheres solid acid by a facile chemical activation route

Energy Technology Data Exchange (ETDEWEB)

Chang, Binbin, E-mail: changbinbin806@163.com; Guo, Yanzhen; Yin, Hang; Zhang, Shouren; Yang, Baocheng, E-mail: baochengyang@yahoo.com

2015-01-15

Generally, porous carbon nanospheres materials are usually prepared via a template method, which is a multi-steps and high-cost strategy. Here, we reported a porous carbon nanosphere solid acid with high surface area and superior porosity, as well as uniform nanospheical morphology, which prepared by a facile chemical activation with ZnCl{sub 2} using resorcinol-formaldehyde (RF) resins spheres as precursor. The activation of RF resins spheres by ZnCl{sub 2} at 400 °C brought high surface area and large volume, and simultaneously retained numerous oxygen-containing and hydrogen-containing groups due to the relatively low processing temperature. The presence of these functional groups is favorable for the modification of –SO{sub 3}H groups by a followed sulfonation treating with sulphuric acid and organic sulfonic acid. The results of N{sub 2} adsorption–desorption and electron microscopy clearly showed the preservation of porous structure and nanospherical morphology. Infrared spectra certified the variation of surface functional groups after activation and the successful modification of –SO{sub 3}H groups after sulfonation. The acidities of catalysts were estimated by an indirect titration method and the modified amount of –SO{sub 3}H groups were examined by energy dispersive spectra. The results suggested sulfonated porous carbon nanospheres catalysts possessed high acidities and –SO{sub 3}H densities, which endowed their significantly catalytic activities for biodiesel production. Furthermore, their excellent stability and recycling property were also demonstrated by five consecutive cycles. - Graphical abstract: Sulfonated porous carbon nanospheres with high surface area and superior catalytic performance were prepared by a facile chemical activation route. - Highlights: • Porous carbon spheres solid acid prepared by a facile chemical activation. • It owns high surface area, superior porosity and uniform spherical morphology. • It possesses

Identification of Robust Terminal-Area Routes in Convective Weather

Science.gov (United States)

Pfeil, Diana Michalek; Balakrishnan, Hamsa

2012-01-01

Convective weather is responsible for large delays and widespread disruptions in the U.S. National Airspace System, especially during summer. Traffic flow management algorithms require reliable forecasts of route blockage to schedule and route traffic. This paper demonstrates how raw convective weather forecasts, which provide deterministic predictions of the vertically integrated liquid (the precipitation content in a column of airspace) can be translated into probabilistic forecasts of whether or not a terminal area route will be blocked. Given a flight route through the terminal area, we apply techniques from machine learning to determine the likelihood that the route will be open in actual weather. The likelihood is then used to optimize terminalarea operations by dynamically moving arrival and departure routes to maximize the expected capacity of the terminal area. Experiments using real weather scenarios on stormy days show that our algorithms recommend that a terminal-area route be modified 30% of the time, opening up 13% more available routes that were forecast to be blocked during these scenarios. The error rate is low, with only 5% of cases corresponding to a modified route being blocked in reality, whereas the original route is in fact open. In addition, for routes predicted to be open with probability 0.95 or greater by our method, 96% of these routes (on average over time horizon) are indeed open in the weather that materializes

SOME IMPORTANT FACTORS AFFECTING EVOLUTION OF ACTIVITY BASED COSTING (ABC) SYSTEM IN EGYPTIAN MANUFACTURING FIRMS

OpenAIRE

Karim MAMDOUH ABBAS

2014-01-01

The present investigation aims to determine the factors affecting evolution of Activity Based Costing (ABC) system in Egyptian case. The study used the survey method to describe and analyze these factors in some Egyptian firms. The population of the study is Egyptian manufacturing firms. Accordingly, the number of received questionnaires was 392 (23 Egyptian manufacturing firms) in the first half of 2013. Finally, the study stated some influencing factors for evolution this system (ABC) in Eg...

Route Generation for a Synthetic Character (BOT) Using a Partial or Incomplete Knowledge Route Generation Algorithm in UT2004 Virtual Environment

Science.gov (United States)

Hanold, Gregg T.; Hanold, David T.

2010-01-01

This paper presents a new Route Generation Algorithm that accurately and realistically represents human route planning and navigation for Military Operations in Urban Terrain (MOUT). The accuracy of this algorithm in representing human behavior is measured using the Unreal Tournament(Trademark) 2004 (UT2004) Game Engine to provide the simulation environment in which the differences between the routes taken by the human player and those of a Synthetic Agent (BOT) executing the A-star algorithm and the new Route Generation Algorithm can be compared. The new Route Generation Algorithm computes the BOT route based on partial or incomplete knowledge received from the UT2004 game engine during game play. To allow BOT navigation to occur continuously throughout the game play with incomplete knowledge of the terrain, a spatial network model of the UT2004 MOUT terrain is captured and stored in an Oracle 11 9 Spatial Data Object (SOO). The SOO allows a partial data query to be executed to generate continuous route updates based on the terrain knowledge, and stored dynamic BOT, Player and environmental parameters returned by the query. The partial data query permits the dynamic adjustment of the planned routes by the Route Generation Algorithm based on the current state of the environment during a simulation. The dynamic nature of this algorithm more accurately allows the BOT to mimic the routes taken by the human executing under the same conditions thereby improving the realism of the BOT in a MOUT simulation environment.

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

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.

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.

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.

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

Science.gov (United States)

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

2013-02-07

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 residential streets as "Bicycle Boulevards." We hypothesized that cyclist exposure to air pollution would be lower on these Bicycle Boulevards when compared to busier roads and this elevated exposure may result in reduced lung function. We recruited 15 healthy adults to cycle on two routes - a low-traffic Bicycle Boulevard route and a high-traffic route. Each participant cycled on the low-traffic route once and the high-traffic route once. We mounted pollutant monitors and a global positioning system (GPS) on the bicycles. The monitors were all synced to GPS time so pollutant measurements could be spatially plotted. We measured lung function using spirometry before and after each bike ride. We found that fine and ultrafine particulate matter, carbon monoxide, and black carbon were all elevated on the high-traffic route compared to the low-traffic route. There were no corresponding changes in the lung function of healthy non-asthmatic study subjects. We also found that wind-speed affected pollution concentrations. These results suggest that by selecting low-traffic Bicycle Boulevards instead of heavily trafficked roads, cyclists can reduce their exposure to vehicle-related air pollution. The lung function results indicate that elevated pollutant exposure may not have acute negative effects on healthy cyclists, but further research is necessary to determine long-term effects on a more diverse population. This study and broader field of research have the potential to encourage policy-makers and city planners to expand infrastructure to

Out of the dark: 350 million years of conservatism and evolution in diel activity patterns in vertebrates.

Science.gov (United States)

Anderson, Samantha R; Wiens, John J

2017-08-01

Many animals are active only during a particular time (e.g., day vs. night), a partitioning that may have important consequences for species coexistence. An open question is the extent to which this diel activity niche is evolutionarily conserved or labile. Here, we analyze diel activity data across a phylogeny of 1914 tetrapod species. We find strong phylogenetic signal, showing that closely related species tend to share similar activity patterns. Ancestral reconstructions show that nocturnality was the most likely ancestral diel activity pattern for tetrapods and many major clades within it (e.g., amphibians, mammals). Remarkably, nocturnal activity appears to have been maintained continuously in some lineages for ∼350 million years. Thus, we show that traits involved in local-scale resource partitioning can be conserved over strikingly deep evolutionary time scales. We also demonstrate a potentially important (but often overlooked) metric of niche conservatism. Finally, we show that diurnal lineages appear to have faster speciation and diversification rates than nocturnal lineages, which may explain why there are presently more diurnal tetrapod species even though diurnality appears to have evolved more recently. Overall, our results may have implications for studies of community ecology, species richness, and the evolution of diet and communication systems. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

War and peace: morphemes and full forms in a noninteractive activation parallel dual-route model.

Science.gov (United States)

Baayen, H; Schreuder, R

This article introduces a computational tool for modeling the process of morphological segmentation in visual and auditory word recognition in the framework of a parallel dual-route model. Copyright 1999 Academic Press.

Is Entrepreneurship a Route Out of Deprivation?

DEFF Research Database (Denmark)

Frankish, Julian S.; Roberts, Richard G.; Coad, Alexander Jean-Luc

2014-01-01

Frankish J. S., Roberts R. G., Coad A. and Storey D. J. Is entrepreneurship a route out of deprivation?, Regional Studies. This paper investigates whether entrepreneurship constitutes a route out of deprivation for those living in deprived areas. The measure of income/wealth used is based...... the wealth distribution. Hence, entrepreneurship can be a route out of deprivation....

Molten salts activated by high-energy milling: A useful, low-temperature route for the synthesis of multiferroic compounds

Energy Technology Data Exchange (ETDEWEB)

Hernández-Ramírez, Anayantzin; Martínez-Luévanos, Antonia [Facultad de Ciencias Químicas, Universidad Autónoma de Coahuila, V. Carranza s/n, Saltillo, Coahuila 25280 (Mexico); Fuentes, Antonio F. [CINVESTAV Unidad Saltillo, Apdo. Postal 663, Saltillo, Coahuila 25000 (Mexico); Earth and Environmental Science, University of Michigan, 3514 C.C. Little Building, 1100 N. University Avenue, Ann Arbor, MI 48109-1005 (United States); Nelson, Anna-Gay D.; Ewing, Rodney C. [Earth and Environmental Science, University of Michigan, 3514 C.C. Little Building, 1100 N. University Avenue, Ann Arbor, MI 48109-1005 (United States); Montemayor, Sagrario M., E-mail: smmontemayor@gmail.com [Facultad de Ciencias Químicas, Universidad Autónoma de Coahuila, V. Carranza s/n, Saltillo, Coahuila 25280 (Mexico); Earth and Environmental Science, University of Michigan, 3514 C.C. Little Building, 1100 N. University Avenue, Ann Arbor, MI 48109-1005 (United States)

2014-01-25

Highlights: • The synthesis route purposed demonstrates the formation of BiFeO{sub 3} at only 500 °C. • The magnetic and ferroelectric properties are comparable to those of bulk BiFeO{sub 3}. • By this route, several phases in Bi{sub 1−x}La{sub x}FeO{sub 3} system are obtained at only 500 °C. • The route developed here could be useful to synthesize other perovskite-type oxides. -- Abstract: There are only a few multiferroic compounds, among which BiFeO{sub 3} is the most important. Research the synthesis of bismuth ferrite, with novel and improved magnetic and electrical properties, has been mainly based on the use of hydrothermal or sol gel methods. However, these methods require either rather extreme conditions or several steps for synthesis. We demonstrate that the use of molten salts, activated by high energy milling, results in pure nanometric BiFeO{sub 3}, LaFeO{sub 3} and intermediate phases in the Bi{sub 1−x}La{sub x}FeO{sub 3} system. The chemical reagents used are Bi(NO{sub 3}){sub 3}⋅5H{sub 2}O, La(NO{sub 3}){sub 3}⋅6H{sub 2}O, Fe(NO{sub 3}){sub 3}⋅9H{sub 2}O and NaOH. A brief milling process of the reagents creates an amorphous precursor and crystalline NaNO{sub 3}. The thermal treatment of the precursors, at 500 °C for two hours, produces a crystalline mixture of Bi{sub 1−x}La{sub x}FeO{sub 3} and NaNO{sub 3}. Simple washing eliminates the NaNO{sub 3}. The characterization of intermediates and final products, through thermal analysis, X-ray diffraction and scanning electronic microscopy, allows the inference of possible mechanism. In addition, vibrating sample magnetometry (VSM) and ferroelectric tests show the typical magnetic and electric polarization loops characteristic of these materials even when formed at the nano-scale.

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.

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)

Oxygen Evolution at Manganite Perovskite Ruddlesden-Popper Type Particles: Trends of Activity on Structure, Valence and Covalence

Directory of Open Access Journals (Sweden)

Majid Ebrahimizadeh Abrishami

2016-11-01

Full Text Available An improved understanding of the correlation between the electronic properties of Mn-O bonds, activity and stability of electro-catalysts for the oxygen evolution reaction (OER is of great importance for an improved catalyst design. Here, an in-depth study of the relation between lattice structure, electronic properties and catalyst performance of the perovskite Ca1−xPrxMnO3 and the first-order RP-system Ca2−xPrxMnO4 at doping levels of x = 0, 0.25 and 0.5 is presented. Lattice structure is determined by X-ray powder diffraction and Rietveld refinement. X-ray absorption spectroscopy of Mn-L and O-K edges gives access to Mn valence and covalency of the Mn-O bond. Oxygen evolution activity and stability is measured by rotating ring disc electrode studies. We demonstrate that the highest activity and stability coincidences for systems with a Mn-valence state of +3.7, though also requiring that the covalency of the Mn-O bond has a relative minimum. This observation points to an oxygen evolution mechanism with high redox activity of Mn. Covalency should be large enough for facile electron transfer from adsorbed oxygen species to the MnO6 network; however, it should not be hampered by oxidation of the lattice oxygen, which might cause a crossover to material degradation. Since valence and covalency changes are not entirely independent, the introduction of the energy position of the eg↑ pre-edge peak in the O-K spectra as a new descriptor for oxygen evolution is suggested, leading to a volcano-like representation of the OER activity.

Self-optimization of the active site of molybdenum disulfide by an irreversible phase transition during photocatalytic hydrogen evolution

Energy Technology Data Exchange (ETDEWEB)

Wang, Longlu; Duan, Xidong; Liu, Chengbin; Zhang, Shuqu; Zeng, Yunxiong [State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha (China); Liu, Xia; Pei, Yong [Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, Xiangtan University (China); Luo, Jinming; Crittenden, John [Brook Byers Institute for Sustainable Systems and School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA (United States); Duan, Xiangfeng [Department of Chemistry and Biochemistry, University of California, Los Angeles, CA (United States)

2017-06-19

The metallic 1T-MoS{sub 2} has attracted considerable attention as an effective catalyst for hydrogen evolution reactions (HERs). However, the fundamental mechanism about the catalytic activity of 1T-MoS{sub 2} and the associated phase evolution remain elusive and controversial. Herein, we prepared the most stable 1T-MoS{sub 2} by hydrothermal exfoliation of MoS{sub 2} nanosheets vertically rooted into rigid one-dimensional TiO{sub 2} nanofibers. The 1T-MoS{sub 2} can keep highly stable over one year, presenting an ideal model system for investigating the HER catalytic activities as a function of the phase evolution. Both experimental studies and theoretical calculations suggest that 1T phase can be irreversibly transformed into a more active 1T' phase as true active sites in photocatalytic HERs, resulting in a ''catalytic site self-optimization''. Hydrogen atom adsorption is the major driving force for this phase transition. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

Energy-Aware Routing Protocol for Ad Hoc Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Mann Raminder P

2005-01-01

Full Text Available Wireless ad hoc sensor networks differ from wireless ad hoc networks from the following perspectives: low energy, lightweight routing protocols, and adaptive communication patterns. This paper proposes an energy-aware routing protocol (EARP suitable for ad hoc wireless sensor networks and presents an analysis for its energy consumption in various phases of route discovery and maintenance. Based on the energy consumption associated with route request processing, EARP advocates the minimization of route requests by allocating dynamic route expiry times. This paper introduces a unique mechanism for estimation of route expiry time based on the probability of route validity, which is a function of time, number of hops, and mobility parameters. In contrast to AODV, EARP reduces the repeated flooding of route requests by maintaining valid routes for longer durations.

A study of routing algorithms for SCI-Based multistage networks

International Nuclear Information System (INIS)

Wu Bin; Kristiansen, E.; Skaali, B.; Bogaerts, A.; )

1994-03-01

The report deals with a particular class of multistage Scalable Coherent Interface (SCI) network systems and two important routing algorithms, namely self-routing and table-look up routing. The effect of routing delay on system performance is investigated by simulations. Adaptive routing and deadlock-free routing are studied. 8 refs., 11 figs., 1 tab

Towards seasonal Arctic shipping route predictions

Science.gov (United States)

Haines, K.; Melia, N.; Hawkins, E.; Day, J. J.

2017-12-01

In our previous work [1] we showed how trans-Arctic shipping routes would become more available through the 21st century as sea ice declines, using CMIP5 models with means and stds calibrated to PIOMAS sea ice observations. Sea ice will continue to close shipping routes to open water vessels through the winter months for the foreseeable future so the availability of open sea routes will vary greatly from year to year. Here [2] we look at whether the trans-Arctic shipping season period can be predicted in seasonal forecasts, again using several climate models, and testing both perfect and imperfect knowledge of the initial sea ice conditions. We find skilful predictions of the upcoming summer shipping season can be made from as early as January, although typically forecasts may show lower skill before a May `predictability barrier'. Focussing on the northern sea route (NSR) off Siberia, the date of opening of this sea route is twice as variable as the closing date, and this carries through to reduced predictability at the start of the season. Under climate change the later freeze-up date accounts for 60% of the lengthening season, Fig1 We find that predictive skill is state dependent with predictions for high or low ice years exhibiting greater skill than for average ice years. Forecasting the exact timing of route open periods is harder (more weather dependent) under average ice conditions while in high and low ice years the season is more controlled by the initial ice conditions from spring onwards. This could be very useful information for companies planning vessel routing for the coming season. We tested this dependence on the initial ice conditions by changing the initial ice state towards climatologically average conditions and show directly that early summer sea-ice thickness information is crucial to obtain skilful forecasts of the coming shipping season. Mechanisms for this are discussed. This strongly suggests that good sea ice thickness observations

SOME IMPORTANT FACTORS AFFECTING EVOLUTION OF ACTIVITY BASED COSTING (ABC SYSTEM IN EGYPTIAN MANUFACTURING FIRMS

Directory of Open Access Journals (Sweden)

Karim MAMDOUH ABBAS

2014-04-01

Full Text Available The present investigation aims to determine the factors affecting evolution of Activity Based Costing (ABC system in Egyptian case. The study used the survey method to describe and analyze these factors in some Egyptian firms. The population of the study is Egyptian manufacturing firms. Accordingly, the number of received questionnaires was 392 (23 Egyptian manufacturing firms in the first half of 2013. Finally, the study stated some influencing factors for evolution this system (ABC in Egyptian manufacturing firms.

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

Lessons learned by southern states in designating alternative routes

International Nuclear Information System (INIS)

1989-08-01

The purpose of this report is to discuss the ''lessons learned'' by the five states within the southem region that have designated alternative or preferred routes under the regulations of the Department of Transportation (DOT) established for the transportation of radioactive materials. The document was prepared by reviewing applicable federal laws and regulations, examining state reports and documents and contacting state officials and routing agencies involved in making routing decisions. In undertaking this project, the Southern States Energy Board hopes to reveal the process used by states that have designated alternative routes and thereby share their experiences (i.e., lessons learned) with other southern states that have yet to make designations. Under DOT regulations (49 CFR 177.826), carriers of highway route controlled quantities of radioactive materials (which include spent nuclear fuel and high-level waste) must use preferred routes selected to reduce time in transit. Such preferred routes consist of (1) an interstate system highway with use of an interstate system bypass or beltway around cities when available, and (2) alternate routes selected by a ''state routing agency.''

Quantum chemistry-assisted synthesis route development

International Nuclear Information System (INIS)

Hori, Kenji; Sumimoto, Michinori; Murafuji, Toshihiro

2015-01-01

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 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

Route Choice Model Based on Game Theory for Commuters

Directory of Open Access Journals (Sweden)

Licai Yang

2016-06-01

Full Text Available The traffic behaviours of commuters may cause traffic congestion during peak hours. Advanced Traffic Information System can provide dynamic information to travellers. Due to the lack of timeliness and comprehensiveness, the provided information cannot satisfy the travellers’ needs. Since the assumptions of traditional route choice model based on Expected Utility Theory conflict with the actual situation, a route choice model based on Game Theory is proposed to provide reliable route choice to commuters in actual situation in this paper. The proposed model treats the alternative routes as game players and utilizes the precision of predicted information and familiarity of traffic condition to build a game. The optimal route can be generated considering Nash Equilibrium by solving the route choice game. Simulations and experimental analysis show that the proposed model can describe the commuters’ routine route choice decisionexactly and the provided route is reliable.

Anti-hierarchical evolution of the active galactic nucleus space density in a hierarchical universe

International Nuclear Information System (INIS)

Enoki, Motohiro; Ishiyama, Tomoaki; Kobayashi, Masakazu A. R.; Nagashima, Masahiro

2014-01-01

Recent observations show that the space density of luminous active galactic nuclei (AGNs) peaks at higher redshifts than that of faint AGNs. This downsizing trend in the AGN evolution seems to be contradictory to the hierarchical structure formation scenario. In this study, we present the AGN space density evolution predicted by a semi-analytic model of galaxy and AGN formation based on the hierarchical structure formation scenario. We demonstrate that our model can reproduce the downsizing trend of the AGN space density evolution. The reason for the downsizing trend in our model is a combination of the cold gas depletion as a consequence of star formation, the gas cooling suppression in massive halos, and the AGN lifetime scaling with the dynamical timescale. We assume that a major merger of galaxies causes a starburst, spheroid formation, and cold gas accretion onto a supermassive black hole (SMBH). We also assume that this cold gas accretion triggers AGN activity. Since the cold gas is mainly depleted by star formation and gas cooling is suppressed in massive dark halos, the amount of cold gas accreted onto SMBHs decreases with cosmic time. Moreover, AGN lifetime increases with cosmic time. Thus, at low redshifts, major mergers do not always lead to luminous AGNs. Because the luminosity of AGNs is correlated with the mass of accreted gas onto SMBHs, the space density of luminous AGNs decreases more quickly than that of faint AGNs. We conclude that the anti-hierarchical evolution of the AGN space density is not contradictory to the hierarchical structure formation scenario.

Anti-hierarchical evolution of the active galactic nucleus space density in a hierarchical universe

Energy Technology Data Exchange (ETDEWEB)

Enoki, Motohiro [Faculty of Business Administration, Tokyo Keizai University, Kokubunji, Tokyo 185-8502 (Japan); Ishiyama, Tomoaki [Center for Computational Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); Kobayashi, Masakazu A. R. [Research Center for Space and Cosmic Evolution, Ehime University, Matsuyama, Ehime 790-8577 (Japan); Nagashima, Masahiro, E-mail: enokimt@tku.ac.jp [Faculty of Education, Nagasaki University, Nagasaki, Nagasaki 852-8521 (Japan)

2014-10-10

Recent observations show that the space density of luminous active galactic nuclei (AGNs) peaks at higher redshifts than that of faint AGNs. This downsizing trend in the AGN evolution seems to be contradictory to the hierarchical structure formation scenario. In this study, we present the AGN space density evolution predicted by a semi-analytic model of galaxy and AGN formation based on the hierarchical structure formation scenario. We demonstrate that our model can reproduce the downsizing trend of the AGN space density evolution. The reason for the downsizing trend in our model is a combination of the cold gas depletion as a consequence of star formation, the gas cooling suppression in massive halos, and the AGN lifetime scaling with the dynamical timescale. We assume that a major merger of galaxies causes a starburst, spheroid formation, and cold gas accretion onto a supermassive black hole (SMBH). We also assume that this cold gas accretion triggers AGN activity. Since the cold gas is mainly depleted by star formation and gas cooling is suppressed in massive dark halos, the amount of cold gas accreted onto SMBHs decreases with cosmic time. Moreover, AGN lifetime increases with cosmic time. Thus, at low redshifts, major mergers do not always lead to luminous AGNs. Because the luminosity of AGNs is correlated with the mass of accreted gas onto SMBHs, the space density of luminous AGNs decreases more quickly than that of faint AGNs. We conclude that the anti-hierarchical evolution of the AGN space density is not contradictory to the hierarchical structure formation scenario.

On line routing per mobile phone

DEFF Research Database (Denmark)

Bieding, Thomas; Görtz, Simon; Klose, Andreas

2009-01-01

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....... 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...

A tree routing protocol for cognitive radio network

Directory of Open Access Journals (Sweden)

Mohammed Hashem

2017-07-01

Full Text Available Cognitive Radio (CR technology is an agile solution for spectrum congestion and spectrum access utilization problems that result from the legacy fixed spectrum management policies. CR technology can exploit unused licensed band to meet the increasing demand for radio frequency. The routing process faces many challenges in CR Network (CRN such as the absence of centralized infrastructure, the coordination between the routing module and spectrum management module, in addition to the frequent link failure due to the sudden appearance of PUs. In this paper we propose a Tree routing protocol for cognitive radio network (C-TRP that jointly utilizes the tree routing algorithm with a spectrum management module in routing decisions, and also we proposed a new metric used in taking the best route decisions. In addition, we enhance the traditional tree routing algorithm by using a neighbor table technique that speeds up the forwarding data packets. Moreover, we add a robust recovery module to C-TRP to resume the network in case of the link failure. The main motivation in the design of C-TRP is quick data transmission and maximization of date rates. The performance evaluation is carried out in NS2 simulator. The simulation results proved that C-TRP protocol achieves better performance in terms of average “PDR”, “end-to-end delay” and “routing overhead ratio “compared to “CTBR” and “STOD-RP” routing protocols.

Route Network Construction with Location-Direction-Enabled Photographs

Science.gov (United States)

Fujita, Hideyuki; Sagara, Shota; Ohmori, Tadashi; Shintani, Takahiko

2018-05-01

We propose a method for constructing a geometric graph for generating routes that summarize a geographical area and also have visual continuity by using a set of location-direction-enabled photographs. A location- direction-enabled photograph is a photograph that has information about the location (position of the camera at the time of shooting) and the direction (direction of the camera at the time of shooting). Each nodes of the graph corresponds to a location-direction-enabled photograph. The location of each node is the location of the corresponding photograph, and a route on the graph corresponds to a route in the geographic area and a sequence of photographs. The proposed graph is constructed to represent characteristic spots and paths linking the spots, and it is assumed to be a kind of a spatial summarization of the area with the photographs. Therefore, we call the routes on the graph as spatial summary route. Each route on the proposed graph also has a visual continuity, which means that we can understand the spatial relationship among the continuous photographs on the route such as moving forward, backward, turning right, etc. In this study, when the changes in the shooting position and shooting direction satisfied a given threshold, the route was defined to have visual continuity. By presenting the photographs in order along the generated route, information can be presented sequentially, while maintaining visual continuity to a great extent.

Development of safe routes for children in urban environment

Science.gov (United States)

Koryagin, M. E.; Medvedev, V. I.; Strykov, P. G.

2018-01-01

The matter of development of safe travel routes for children between school and home is analyzed. The availability of various applications and devices to identify the location of the child and his/her travel routes is noted. The main factors to be taken into account when planning children travel routes are described. The most popular Russian services for route planning, Google, Yandex, and 2GIS, are discussed. These services are shown to have a number of shortcomings which does not allow them to choose really safe routes. A decision on making the route selection by two criteria (the travel time and the probability of an accident) is obtained. As a numerical example, the Pareto area for possible routes is constructed.

A study of inoculation route and dosage levels on embryonated chicken eggs as media for testing tea mistlestoe (Scurrula oortiana extract activity

Directory of Open Access Journals (Sweden)

Sri Murtini

2006-06-01

Full Text Available Tea mistlestoe extract (Scurrula oortiana has cytotoxic activity which is potential to be used in preventing viral induced-chicken tumor. The following study was designed to evaluate the effects of different inoculation routes, dosage levels, and strains of embryonated chicken eggs as media for testing the tea mistlestoe extract (Scurrula oortiana antiviral activity. Proper inoculation route was examined by inoculation of the extract at dose level of 0,2 mg/egg into embryonated layer eggs via allantoic cavity, chorio-allantoic membrane, and yolk sac. Effect of dose level of tea mistlestoe extract on embryo development was examined in groups of embryonated broiler eggs inoculated with the extract at 0.02, 0.2, 2, 20, or 200 mg/egg. Inoculation of tea mistlestoe extract into allantoic cavity was the safest procedure as indicated by the absence of embryos mortality, and faster embryo growth compared to those of chorio-allantoic membrane and yolk sac-inoculated eggs. The extract induced different growth effects when inoculated into embryonated layer or broiler eggs. Administration of the extract at dose levels between 0,02–200 mg/egg reduced significantly the weight of broiler embryoes, but not the relative weights of liver, heart and spleen. Administration of similar dosage in layer embryoes did not cause any significant difference in the embryoes weight. This study suggests that the study of antiviral activity of tea mistlestoe extract in embryonated chicken eggs should be carried out on embryonated eggs of layer breeds and the extract should be inoculated via allantoic cavity.

A Performance Study of LEACH and Direct Diffusion Routing Protocols in Wireless Sensor Network

International Nuclear Information System (INIS)

Fakher, S.; Sharshar, K.; Moawad, M.I.; Shokair, M.

2016-01-01

The Wireless Sensor Network (WSN) is composed of a large number of sensor nodes with limited computation communication, and battery facilities. One of the common applications of this network is environment monitoring through sensing motion, measuring temperature, humidity and radiation. One of the basic activities in WSN is data gathering which represents a great challenge. Many routing protocols are proposed for that network to collect and aggregate the data. The most popular ones are hierarchy and data centric routing protocols. The main goal of this study is to identify the most preferable routing protocol, to be used in each mobility model. This paper studies the performance of LEACH (Low Energy Adaptive Clustering Hierarchy) from hierarchy routing protocol and direct diffusion from data centric routing protocol which is not clarified until now. Moreover, a comparison between LEACH and direct diffusion protocol using NS2 simulator will be made, and an analysis of these protocols will be conducted. The comparison includes packet delivery ratio, throughput, average energy ratio, average delay, network lifetime, and routing overhead. The performance is evaluated by varying the number of sensor nodes under three mobility models Reference Point Group Mobility Model (RPGM), Manhattan and random waypoint mobility model. Simulation results show that LEACH routing protocol has a good performance in RPGM and Manhattan than random waypoint mobility model. Direct diffusion has a good performance in random waypoint mobility model than in RPGM and Manhattan mobility model

Routing architecture and security for airborne networks

Science.gov (United States)

Deng, Hongmei; Xie, Peng; Li, Jason; Xu, Roger; Levy, Renato

2009-05-01

Airborne networks are envisioned to provide interconnectivity for terrestial and space networks by interconnecting highly mobile airborne platforms. A number of military applications are expected to be used by the operator, and all these applications require proper routing security support to establish correct route between communicating platforms in a timely manner. As airborne networks somewhat different from traditional wired and wireless networks (e.g., Internet, LAN, WLAN, MANET, etc), security aspects valid in these networks are not fully applicable to airborne networks. Designing an efficient security scheme to protect airborne networks is confronted with new requirements. In this paper, we first identify a candidate routing architecture, which works as an underlying structure for our proposed security scheme. And then we investigate the vulnerabilities and attack models against routing protocols in airborne networks. Based on these studies, we propose an integrated security solution to address routing security issues in airborne networks.

Waste Collection Vehicle Routing Problem: Literature Review

OpenAIRE

Hui Han; Eva Ponce Cueto

2015-01-01

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 litera...

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.

MIL-125-NH2@TiO2 Core-Shell Particles Produced by a Post-Solvothermal Route for High-Performance Photocatalytic H2 Production.

Science.gov (United States)

Zhang, Bingxing; Zhang, Jianling; Tan, Xiuniang; Shao, Dan; Shi, Jinbiao; Zheng, Lirong; Zhang, Jing; Yang, Guanying; Han, Buxing

2018-05-02

Metal-organic frameworks (MOFs) have proven to be an interesting class of sacrificial precursors of functional inorganic materials for catalysis, energy storage, and conversion applications. However, the controlled synthesis of MOF-derived materials with desirable compositions, structures, and properties still remains a big challenge. Herein, we propose a post-solvothermal route for the outer-to-inner loss of organic linkers from MOF, which is simple, rapid, and controllable and can be operated at temperature much lower than that of the commonly adopted pyrolysis method. By such a strategy, the MIL-125-NH 2 particles coated by TiO 2 nanosheets were produced, and the thickness of TiO 2 shell can be easily tuned. The MIL-125-NH 2 @TiO 2 core-shell particles combine the advantages of highly active TiO 2 nanosheets, MIL-125-NH 2 photosensitizer, plenty of linker defects and oxygen vacancies, and mesoporous structure, which allows them to be utilized as photocatalysts for the visible-light-driven hydrogen production reaction. It is remarkable that the hydrogen evolution rate by MIL-125-NH 2 @TiO 2 can be enhanced 70 times compared with the pristine MIL-125-NH 2 . Such a route can be easily applied to the synthesis of different kinds of MOF-derived functional materials.

Optimizing departure times in vehicle routes

NARCIS (Netherlands)

Kok, A.L.; Hans, Elias W.; Schutten, Johannes 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

Demonstrating the unit hydrograph and flow routing processes involving active student participation - a university lecture experiment

Science.gov (United States)

Schulz, Karsten; Burgholzer, Reinhard; Klotz, Daniel; Wesemann, Johannes; Herrnegger, Mathew

2018-05-01

The unit hydrograph (UH) has been one of the most widely employed hydrological modelling techniques to predict rainfall-runoff behaviour of hydrological catchments, and is still used to this day. Its concept is based on the idea that a unit of effective precipitation per time unit (e.g. mm h-1) will always lead to a specific catchment response in runoff. Given its relevance, the UH is an important topic that is addressed in most (engineering) hydrology courses at all academic levels. While the principles of the UH seem to be simple and easy to understand, teaching experiences in the past suggest strong difficulties in students' perception of the UH theory and application. In order to facilitate a deeper understanding of the theory and application of the UH for students, we developed a simple and cheap lecture theatre experiment which involved active student participation. The seating of the students in the lecture theatre represented the hydrological catchment in its size and form. A set of plastic balls, prepared with a piece of magnetic strip to be tacked to any white/black board, each represented a unit amount of effective precipitation. The balls are evenly distributed over the lecture theatre and routed by some given rules down the catchment to the catchment outlet, where the resulting hydrograph is monitored and illustrated at the black/white board. The experiment allowed an illustration of the underlying principles of the UH, including stationarity, linearity, and superposition of the generated runoff and subsequent routing. In addition, some variations of the experimental setup extended the UH concept to demonstrate the impact of elevation, different runoff regimes, and non-uniform precipitation events on the resulting hydrograph. In summary, our own experience in the classroom, a first set of student exams, as well as student feedback and formal evaluation suggest that the integration of such an experiment deepened the learning experience by active

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...... 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 k-LocVRP. In obtaining this result, we introduce a common generalization of the k-median and minimum...... spanning tree problems (called k median forest), which might be of independent interest. We give a local-search based (3+ε)-approximation algorithm for k median forest, which leads to a (12+ε)-approximation algorithm for k-LocVRP, for any constant ε>0....

Locating Depots for Capacitated Vehicle Routing

DEFF Research Database (Denmark)

Gørtz, Inge Li; Nagarajan, Viswanath

2016-01-01

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 k-LocVRP. In obtaining this result, we introduce a common generalization of the k-median and minimum...... spanning tree problems (called k median forest), which might be of independent interest. We give a local-search based (3+ε)-approximation algorithm for k median forest, which leads to a (12+ε)-approximation algorithm for k-LocVRP, for any constant ε>0.......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...

Routes and Stations

Data.gov (United States)

Department of Homeland Security — he Routes_Stations table is composed of fixed rail transit systems within the Continental United States, Alaska, Hawaii, the District of Columbia, and Puerto Rico....

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

Policy implications of Iran's Nuclear Deal in technical terms for the plutonium route, uranium route, covert options, inspections, monitoring and verifications

International Nuclear Information System (INIS)

Pinheiro, Andre Ricardo M.

2017-01-01

The present Paper addresses the policy implications of Joint Comprehensive Plan of Action (JCPOA) known as 'Ian Nuclear Deal', implemented on 16 th January of 2016 between the Iran and the P5+1 countries (the U.S., U.K. France, Germany, Russia, and China), along with the EU in technical terms to analyze the Plutonium Route, Uranium Route and the Covert options and Inspections, Monitoring and Verifications. A historical review is presented to understand how the Iranian Nuclear Program is formed. Following is shown the current nuclear facilities in Iran and its capacity to process nuclear materials. It is analyzed the impact of JCPOA in Uranium and Plutonium routes. Covert Options always will be an option, so the most sensitive impact is related to the new monitoring and verification policies that must ensure real control of illegal procedures. The main conclusion is that the deal postpones the Iran's nuclear program for more than a decade (15 years), delaying Iran's nuclear bomb time from a few months to at least one year, although there is a current latent capacity to develop a nuclear bomb in Uranium route. It also gives IAEA inspectors capability to monitor nuclear activities and prevent to possible development to a nuclear bomb. To arrive in this conclusion an extensive technical analyze of impact of JCPOA in Iran's nuclear capabilities was made to discover how effective is the deal to prevent Iran to build, or acquire a nuclear weapon. (author)

Policy implications of Iran's Nuclear Deal in technical terms for the plutonium route, uranium route, covert options, inspections, monitoring and verifications

Energy Technology Data Exchange (ETDEWEB)

Pinheiro, Andre Ricardo M., E-mail: andrericardopinheiro@usp.br [Universidade de São Paulo (USP), SP (Brazil). Departamento de Engenharia Naval; Guimarães, Leonam dos Santos, E-mail: leonam@eletronuclear.gov.br [Eletrobrás Termonuclear S.A. (ELETRONUCLEAR), Rio de Janeiro, RJ (Brazil)

2017-07-01

The present Paper addresses the policy implications of Joint Comprehensive Plan of Action (JCPOA) known as 'Ian Nuclear Deal', implemented on 16{sup th} January of 2016 between the Iran and the P5+1 countries (the U.S., U.K. France, Germany, Russia, and China), along with the EU in technical terms to analyze the Plutonium Route, Uranium Route and the Covert options and Inspections, Monitoring and Verifications. A historical review is presented to understand how the Iranian Nuclear Program is formed. Following is shown the current nuclear facilities in Iran and its capacity to process nuclear materials. It is analyzed the impact of JCPOA in Uranium and Plutonium routes. Covert Options always will be an option, so the most sensitive impact is related to the new monitoring and verification policies that must ensure real control of illegal procedures. The main conclusion is that the deal postpones the Iran's nuclear program for more than a decade (15 years), delaying Iran's nuclear bomb time from a few months to at least one year, although there is a current latent capacity to develop a nuclear bomb in Uranium route. It also gives IAEA inspectors capability to monitor nuclear activities and prevent to possible development to a nuclear bomb. To arrive in this conclusion an extensive technical analyze of impact of JCPOA in Iran's nuclear capabilities was made to discover how effective is the deal to prevent Iran to build, or acquire a nuclear weapon. (author)

Broadening of neutralization activity to directly block a dominant antibody-driven SARS-coronavirus evolution pathway.

Directory of Open Access Journals (Sweden)

Jianhua Sui

2008-11-01

Full Text Available Phylogenetic analyses have provided strong evidence that amino acid changes in spike (S protein of animal and human SARS coronaviruses (SARS-CoVs during and between two zoonotic transfers (2002/03 and 2003/04 are the result of positive selection. While several studies support that some amino acid changes between animal and human viruses are the result of inter-species adaptation, the role of neutralizing antibodies (nAbs in driving SARS-CoV evolution, particularly during intra-species transmission, is unknown. A detailed examination of SARS-CoV infected animal and human convalescent sera could provide evidence of nAb pressure which, if found, may lead to strategies to effectively block virus evolution pathways by broadening the activity of nAbs. Here we show, by focusing on a dominant neutralization epitope, that contemporaneous- and cross-strain nAb responses against SARS-CoV spike protein exist during natural infection. In vitro immune pressure on this epitope using 2002/03 strain-specific nAb 80R recapitulated a dominant escape mutation that was present in all 2003/04 animal and human viruses. Strategies to block this nAb escape/naturally occurring evolution pathway by generating broad nAbs (BnAbs with activity against 80R escape mutants and both 2002/03 and 2003/04 strains were explored. Structure-based amino acid changes in an activation-induced cytidine deaminase (AID "hot spot" in a light chain CDR (complementarity determining region alone, introduced through shuffling of naturally occurring non-immune human VL chain repertoire or by targeted mutagenesis, were successful in generating these BnAbs. These results demonstrate that nAb-mediated immune pressure is likely a driving force for positive selection during intra-species transmission of SARS-CoV. Somatic hypermutation (SHM of a single VL CDR can markedly broaden the activity of a strain-specific nAb. The strategies investigated in this study, in particular the use of structural

Perspectives on Illegal Routes in Nigeria

African Journals Online (AJOL)

Nneka Umera-Okeke

University of Kwazulu-Natal. Pietermaritzburg, South ... Key Words: Nigeria Immigration Service, Illegal Routes, Security Policing, Border,. State .... transported weapons across borders to sell them in exchange for food or other commodities. ... The study's respondents were of the opinion that illegal routes exist around the ...

Optimizing Departure Times in Vehicle Routes

NARCIS (Netherlands)

Kok, A.L.; Hans, Elias W.; Schutten, Johannes 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

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 to c...

"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.

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.

Sigma Routing Metric for RPL Protocol

Directory of Open Access Journals (Sweden)

Paul Sanmartin

2018-04-01

Full Text Available This paper presents the adaptation of a specific metric for the RPL protocol in the objective function MRHOF. Among the functions standardized by IETF, we find OF0, which is based on the minimum hop count, as well as MRHOF, which is based on the Expected Transmission Count (ETX. However, when the network becomes denser or the number of nodes increases, both OF0 and MRHOF introduce long hops, which can generate a bottleneck that restricts the network. The adaptation is proposed to optimize both OFs through a new routing metric. To solve the above problem, the metrics of the minimum number of hops and the ETX are combined by designing a new routing metric called SIGMA-ETX, in which the best route is calculated using the standard deviation of ETX values between each node, as opposed to working with the ETX average along the route. This method ensures a better routing performance in dense sensor networks. The simulations are done through the Cooja simulator, based on the Contiki operating system. The simulations showed that the proposed optimization outperforms at a high margin in both OF0 and MRHOF, in terms of network latency, packet delivery ratio, lifetime, and power consumption.

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.

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.

THE EVOLUTION OF THE ELECTRIC CURRENT DURING THE FORMATION AND ERUPTION OF ACTIVE-REGION FILAMENTS

Energy Technology Data Exchange (ETDEWEB)

Wang, Jincheng; Yan, Xiaoli; Qu, Zhongquan; Xue, Zhike; Xiang, Yongyuan; Li, Hao, E-mail: egnever@ynao.ac.cn [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China)

2016-02-01

We present a comprehensive study of the electric current related to the formation and eruption of active region filaments in NOAA AR 11884. The vertical current on the solar surface was investigated by using vector magnetograms (VMs) observed by HMI on board the Solar Dynamics Observatory. To obtain the electric current along the filament's axis, we reconstructed the magnetic fields above the photosphere by using nonlinear force-free field extrapolation based on photospheric VMs. Spatio-temporal evolutions of the vertical current on the photospheric surface and the horizontal current along the filament's axis were studied during the long-term evolution and eruption-related period, respectively. The results show that the vertical currents of the entire active region behaved with a decreasing trend and the magnetic fields also kept decreasing during the long-term evolution. For the eruption-related evolution, the mean transverse field strengths decreased before two eruptions and increased sharply after two eruptions in the vicinity of the polarity inversion lines underneath the filament. The related vertical current showed different behaviors in two of the eruptions. On the other hand, a very interesting feature was found: opposite horizontal currents with respect to the current of the filament's axis appeared and increased under the filament before the eruptions and disappeared after the eruptions. We suggest that these opposite currents were carried by the new flux emerging from the photosphere bottom and might be the trigger mechanism for these filament eruptions.

Aldehyde PEGylation of laccase from Trametes versicolor in route to increase its stability: effect on enzymatic activity.

Science.gov (United States)

Mayolo-Deloisa, Karla; González-González, Mirna; Simental-Martínez, Jesús; Rito-Palomares, Marco

2015-03-01

Laccase is a multicopper oxidase that catalyzes the oxidation of phenolic compounds. Laccase can be used in bioremediation, beverage (wine, fruit juice, and beer) processing, ascorbic acid determination, sugar beet pectin gelation baking, and as a biosensor. Recently, the antiproliferative activity of laccase toward tumor cells has been reported. Because of the potential applications of this enzyme, the efforts for enhancing and stabilizing its activity have increased. Thus, the PEGylation of laccase can be an alternative. PEGylation is the covalent attachment of one or more molecules of methoxy poly(ethylene glycol) (mPEG) to a protein. Normally, during the PEGylation reaction, the activity is reduced but the stability increases; thus, it is important to minimize the loss of activity. In this work, the effects of molar ratio (1:4, 1:8, and 1:12), concentration of laccase (6 and 12 mg/ml), reaction time (4 and 17 h), molecular weight, and type of mPEG (20, 30, 40 kDa and 40 kDa-branched) were analyzed. The activity was measured using three substrates: ABTS, 2,6-dimethoxyphenol, and syringaldazine. The best conditions for laccase PEGylation were 12 mg/ml of laccase, molar ratio 1:4, and 4 h reaction time. Under these conditions, the enzyme was able to maintain nearly 100% of its enzymatic activity with ABTS. The PEGylation of laccase has not been extensively explored, so it is important to analyze the effects of this bioconjugation in route to produce a robust modified enzyme. Copyright © 2015 John Wiley & Sons, Ltd.

An adversarial queueing model for online server routing

NARCIS (Netherlands)

Bonifaci, V.

2007-01-01

In an online server routing problem, a vehicle or server moves in a network in order to process incoming requests at the nodes. Online server routing problems have been thoroughly studied using competitive analysis. We propose a new model for online server routing, based on adversarial queueing

41 CFR 109-40.302 - Standard routing principle.

Science.gov (United States)

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Standard routing principle. 109-40.302 Section 109-40.302 Public Contracts and Property Management Federal Property... Standard routing principle. (a) Shipments shall be routed using the mode of transportation, or individual...

Modeling and Performance Analysis of Route-Over and Mesh-Under Routing Schemes in 6LoWPAN under Error-Prone Channel Condition

Directory of Open Access Journals (Sweden)

Tsung-Han Lee

2013-01-01

Full Text Available 6LoWPAN technology has attracted extensive attention recently. It is because 6LoWPAN is one of Internet of Things standard and it adapts to IPv6 protocol stack over low-rate wireless personal area network, such as IEEE 802.15.4. One view is that IP architecture is not suitable for low-rate wireless personal area network. It is a challenge to implement the IPv6 protocol stack into IEEE 802.15.4 devices due to that the size of IPv6 packet is much larger than the maximum packet size of IEEE 802.15.4 in data link layer. In order to solve this problem, 6LoWPAN provides header compression to reduce the transmission overhead for IP packets. In addition, two selected routing schemes, mesh-under and route-over routing schemes, are also proposed in 6LoWPAN to forward IP fragmentations under IEEE 802.15.4 radio link. The distinction is based on which layer of the 6LoWPAN protocol stack is in charge of routing decisions. In route-over routing scheme, the routing distinction is taken at the network layer and, in mesh-under, is taken by the adaptation layer. Thus, the goal of this research is to understand the performance of two routing schemes in 6LoWPAN under error-prone channel condition.

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...

A Novel CAN Tree Coordinate Routing in Content-Addressable Network

Directory of Open Access Journals (Sweden)

Zhongtao Li

2014-09-01

Full Text Available In this paper, we propose a novel approach to improve coordination routing while minimizing the maintenance overhead during nodes churn. It bases on “CAN Tree Routing for Content- Addressable Network” 1 which is a solution for peer-to-peer routing. We concentrated on coordinate routing in this paper. The key idea of our approach is a recursion process to calculate target zone code and search in CAN tree 1. Because the hops are via long links in CAN, it enhances routing flexibility and robustness against failures. Nodes automatically adapt routing table to cope with network change. The routing complexity is , which is much better than a uniform greedy routing, while each node maintains two long links in average.

Sinkhole Avoidance Routing in Wireless Sensor Networks

Science.gov (United States)

2011-05-09

COVERED (From- To) 09-05-2011 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Sinkhole Avoidance Routing in Wireless Sensor Networks 5b . GRANT NUMBER . 5c...reliability of wireless sensor networks. 15. SUBJECT TERMS wireless sensor networks, sinkhole attack, routing protocol 16. SECURITY CLASSIFICATION...Include area code) Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std . Z39.18 1 Sinkhole Avoidance Routing in Wireless Sensor Networks MIDN 1/C

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

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.

A Clustering Routing Protocol for Mobile Ad Hoc Networks

Directory of Open Access Journals (Sweden)

Jinke Huang

2016-01-01

Full Text Available The dynamic topology of a mobile ad hoc network poses a real challenge in the design of hierarchical routing protocol, which combines proactive with reactive routing protocols and takes advantages of both. And as an essential technique of hierarchical routing protocol, clustering of nodes provides an efficient method of establishing a hierarchical structure in mobile ad hoc networks. In this paper, we designed a novel clustering algorithm and a corresponding hierarchical routing protocol for large-scale mobile ad hoc networks. Each cluster is composed of a cluster head, several cluster gateway nodes, several cluster guest nodes, and other cluster members. The proposed routing protocol uses proactive protocol between nodes within individual clusters and reactive protocol between clusters. Simulation results show that the proposed clustering algorithm and hierarchical routing protocol provide superior performance with several advantages over existing clustering algorithm and routing protocol, respectively.

Biodistribution of radiolabelled human dendritic cells injected by various routes

International Nuclear Information System (INIS)

Quillien, Veronique; Moisan, Annick; Carsin, Andre; Lesimple, Thierry; Lefeuvre, Claudia; Bertho, Nicolas; Devillers, Anne; Toujas, Louis; Adamski, Henri; Leberre, Claudine

2005-01-01

The purpose of this study was to investigate the biodistribution of mature dendritic cells (DCs) injected by various routes, during a cell therapy protocol. In the context of a vaccine therapy protocol for melanoma, DCs matured with Ribomunyl and interferon-gamma were labelled with 111 In-oxine and injected into eight patients along various routes: afferent lymphatic vessel (IL) (4 times), lymph node (IN) (5 times) and intradermally (ID) (6 times). Scintigraphic investigations showed that the IL route allowed localisation of 80% of injected radioactivity in eight to ten nodes. In three cases of IN injection, the entire radioactivity stagnated in the injected nodes, while in two cases, migration to adjacent nodes was observed. This migration was detected rapidly after injection, as with IL injections, suggesting that passive transport occurred along the physiological lymphatic pathways. In two of the six ID injections, 1-2% of injected radioactivity reached a proximal lymph node. Migration was detectable in the first hour, but increased considerably after 24 h, suggesting an active migration mechanism. In both of the aforementioned cases, DCs were strongly CCR7-positive, but this feature was not a sufficient condition for effective migration. In comparison with DCs matured with TNF-α, IL-1β, IL-6 and PGE2, our DCs showed a weaker in vitro migratory response to CCL21, despite comparable CCR7 expression, and higher allostimulatory and TH1 polarisation capacities. The IL route allowed reproducible administration of specified numbers of DCs. The IN route sometimes yielded fairly similar results, but not reproducibly. Lastly, we showed that DCs matured without PGE2 that have in vitro TH1 polarisation capacities can migrate to lymph nodes after ID injection. (orig.)

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

Transportation Routing Analysis Geographic Information System (WebTRAGIS) User's Manual

International Nuclear Information System (INIS)

Michelhaugh, R.D.

2000-01-01

In the early 1980s, Oak Ridge National Laboratory (ORNL) developed two transportation routing models: HIGHWAY, which predicts truck transportation routes, and INTERLINE, which predicts rail transportation routes. Both of these models have been used by the U.S. Department of Energy (DOE) community for a variety of routing needs over the years. One of the primary uses of the models has been to determine population-density information, which is used as input for risk assessment with the RADTRAN model, which is available on the TRANSNET computer system. During the recent years, advances in the development of geographic information systems (GISs) have resulted in increased demands from the user community for a GIS version of the ORNL routing models. In April 1994, the DOE Transportation Management Division (EM-261) held a Baseline Requirements Assessment Session with transportation routing experts and users of the HIGHWAY and INTERLINE models. As a result of the session, the development of a new GIS routing model, Transportation Routing Analysis GIS (TRAGIS), was initiated. TRAGIS is a user-friendly, GIS-based transportation and analysis computer model. The older HIGHWAY and INTERLINE models are useful to calculate routes, but they cannot display a graphic of the calculated route. Consequently, many users have experienced difficulty determining the proper node for facilities and have been confused by or have misinterpreted the text-based listing from the older routing models. Some of the primary reasons for the development of TRAGIS are (a) to improve the ease of selecting locations for routing, (b) to graphically display the calculated route, and (c) to provide for additional geographic analysis of the route

Micro-droplet based directed evolution outperforms conventional laboratory evolution

DEFF Research Database (Denmark)

Sjostrom, Staffan L.; Huang, Mingtao; Nielsen, Jens

2014-01-01

We present droplet adaptive laboratory evolution (DrALE), a directed evolution method used to improve industrial enzyme producing microorganisms for e.g. feedstock digestion. DrALE is based linking a desired phenotype to growth rate allowing only desired cells to proliferate. Single cells are con...... a whole-genome mutated library of yeast cells for α-amylase activity....

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...

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....... Subcutaneous injection of melatonin displayed a rapid absorption rate compared to oral administration. Conclusion: Intranasal administration of melatonin has a large potential, and more research in humans is warranted. Transdermal application of melatonin has a possible use in a local application, due to slow...

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.

Route Flap Damping Made Usable

Science.gov (United States)

Pelsser, Cristel; Maennel, Olaf; Mohapatra, Pradosh; Bush, Randy; Patel, Keyur

The Border Gateway Protocol (BGP), the de facto inter-domain routing protocol of the Internet, is known to be noisy. The protocol has two main mechanisms to ameliorate this, MinRouteAdvertisementInterval (MRAI), and Route Flap Damping (RFD). MRAI deals with very short bursts on the order of a few to 30 seconds. RFD deals with longer bursts, minutes to hours. Unfortunately, RFD was found to severely penalize sites for being well-connected because topological richness amplifies the number of update messages exchanged. So most operators have disabled it. Through measurement, this paper explores the avenue of absolutely minimal change to code, and shows that a few RFD algorithmic constants and limits can be trivially modified, with the result being damping a non-trivial amount of long term churn without penalizing well-behaved prefixes' normal convergence process.

Using Sphinx to Improve Onion Routing Circuit Construction

Science.gov (United States)

Kate, Aniket; Goldberg, Ian

This paper presents compact message formats for onion routing circuit construction using the Sphinx methodology developed for mixes. We significantly compress the circuit construction messages for three onion routing protocols that have emerged as enhancements to the Tor anonymizing network; namely, Tor with predistributed Diffie-Hellman values, pairing-based onion routing, and certificateless onion routing. Our new circuit constructions are also secure in the universal composability framework, a property that was missing from the original constructions. Further, we compare the performance of our schemes with their older counterparts as well as with each other.

Improving Glyphosate Oxidation Activity of Glycine Oxidase from Bacillus cereus by Directed Evolution

Science.gov (United States)

Zhan, Tao; Zhang, Kai; Chen, Yangyan; Lin, Yongjun; Wu, Gaobing; Zhang, Lili; Yao, Pei; Shao, Zongze; Liu, Ziduo

2013-01-01

Glyphosate, a broad spectrum herbicide widely used in agriculture all over the world, inhibits 5-enolpyruvylshikimate-3-phosphate synthase in the shikimate pathway, and glycine oxidase (GO) has been reported to be able to catalyze the oxidative deamination of various amines and cleave the C-N bond in glyphosate. Here, in an effort to improve the catalytic activity of the glycine oxidase that was cloned from a glyphosate-degrading marine strain of Bacillus cereus (BceGO), we used a bacteriophage T7 lysis-based method for high-throughput screening of oxidase activity and engineered the gene encoding BceGO by directed evolution. Six mutants exhibiting enhanced activity toward glyphosate were screened from two rounds of error-prone PCR combined with site directed mutagenesis, and the beneficial mutations of the six evolved variants were recombined by DNA shuffling. Four recombinants were generated and, when compared with the wild-type BceGO, the most active mutant B3S1 showed the highest activity, exhibiting a 160-fold increase in substrate affinity, a 326-fold enhancement in catalytic efficiency against glyphosate, with little difference between their pH and temperature stabilities. The role of these mutations was explored through structure modeling and molecular docking, revealing that the Arg51 mutation is near the active site and could be an important residue contributing to the stabilization of glyphosate binding, while the role of the remaining mutations is unclear. These results provide insight into the application of directed evolution in optimizing glycine oxidase function and have laid a foundation for the development of glyphosate-tolerant crops. PMID:24223901

Improving glyphosate oxidation activity of glycine oxidase from Bacillus cereus by directed evolution.

Directory of Open Access Journals (Sweden)

Tao Zhan

Full Text Available Glyphosate, a broad spectrum herbicide widely used in agriculture all over the world, inhibits 5-enolpyruvylshikimate-3-phosphate synthase in the shikimate pathway, and glycine oxidase (GO has been reported to be able to catalyze the oxidative deamination of various amines and cleave the C-N bond in glyphosate. Here, in an effort to improve the catalytic activity of the glycine oxidase that was cloned from a glyphosate-degrading marine strain of Bacillus cereus (BceGO, we used a bacteriophage T7 lysis-based method for high-throughput screening of oxidase activity and engineered the gene encoding BceGO by directed evolution. Six mutants exhibiting enhanced activity toward glyphosate were screened from two rounds of error-prone PCR combined with site directed mutagenesis, and the beneficial mutations of the six evolved variants were recombined by DNA shuffling. Four recombinants were generated and, when compared with the wild-type BceGO, the most active mutant B3S1 showed the highest activity, exhibiting a 160-fold increase in substrate affinity, a 326-fold enhancement in catalytic efficiency against glyphosate, with little difference between their pH and temperature stabilities. The role of these mutations was explored through structure modeling and molecular docking, revealing that the Arg(51 mutation is near the active site and could be an important residue contributing to the stabilization of glyphosate binding, while the role of the remaining mutations is unclear. These results provide insight into the application of directed evolution in optimizing glycine oxidase function and have laid a foundation for the development of glyphosate-tolerant crops.

A Comparative Anatomy of Oil Price Routs: A Review of Four Price Routs between 1985 and 2014

Directory of Open Access Journals (Sweden)

Robert Skinner

2015-11-01

inventories are drawn down. However we are likely to see a bumpy rise in prices rather than a steady recovery such as after 2009. The effects in Canada of the current rout are not Alberta’s alone to suffer, largely owing to the dominance of the resource, labour and technology-intensive oil sands business. Unlike 30 years ago, the oil sands industry is far more enmeshed with a broad spectrum of ancillary industries and activities across the country. Back then, the oil sands made up just 17 per cent of Canada’s total production of crude oil; today, that figure is over 62 per cent. The impacts of the oil sands industry thus are pan-Canadian. The lesson for Alberta and Canada is to rely less on oil-price projections from the seers in the U.S. financial business, who are transfixed by the shale oil industry. Shale oil’s already weak financial viability is even more precarious as the U.S. Federal Reserve ponders a rate hike. This crash was triggered by the over-supply from U.S. shale and Canadian oil sands and the response by Saudi Arabia to hold its market share and to not cut its production. It behoves Canada and Alberta to be more pro-active and pay closer and critical attention to OPEC and in particular to signals from the Gulf producers.

Routing in Wireless Multimedia Home Networks

NARCIS (Netherlands)

Scholten, Johan; Jansen, P.G.; Hop, Laurens

This paper describes an adapted version of the destination sequenced distance vector routing protocol (DSDV) which is suitable to calculate routes in a wireless real-time home network. The home network is based on a IEEE 802.11b ad hoc network and uses a scheduled token to enforce real-time

Tectonic activity and the evolution of submarine canyons: The Cook Strait Canyon system, New Zealand

Science.gov (United States)

Micallef, Aaron; Mountjoy, Joshu; Barnes, Philip; Canals, Miquel; Lastras, Galderic

2016-04-01

Submarine canyons are Earth's most dramatic erosional features, comprising steep-walled valleys that originate in the continental shelf and slope. They play a key role in the evolution of continental margins by transferring sediments into deep water settings and are considered important biodiversity hotspots, pathways for nutrients and pollutants, and analogues of hydrocarbon reservoirs. Although comprising only one third of continental margins worldwide, active margins host more than half of global submarine canyons. We still lack of thorough understanding of the coupling between active tectonics and submarine canyon processes, which is necessary to improve the modelling of canyon evolution in active margins and derive tectonic information from canyon morphology. The objectives of this study are to: (i) understand how tectonic activity influences submarine canyon morphology, processes, and evolution in an active margin, and (2) formulate a generalised model of canyon development in response to tectonic forcing based on morphometric parameters. We fulfil these objectives by analysing high resolution geophysical data and imagery from Cook Strait Canyon system, offshore New Zealand. Using these data, we demonstrate that tectonic activity, in the form of major faults and structurally-generated tectonic ridges, leaves a clear topographic signature on submarine canyon location and morphology, in particular their dendritic and sinuous planform shapes, steep and linear longitudinal profiles, and cross-sectional asymmetry and width. We also report breaks/changes in canyon longitudinal slope gradient, relief and slope-area regression models at the intersection with faults. Tectonic activity gives rise to two types of knickpoints in the Cook Strait Canyon. The first type consists of low slope gradient, rounded and diffusive knickpoints forming as a result of short wavelength folds or fault break outs and being restored to an equilibrium profile by upstream erosion and

Activity and stability trends of perovskite oxides for oxygen evolution catalysis at neutral pH

OpenAIRE

Ling, Chen; Jia, Hongfei; Han, Binghong; Risch, Marcel; Lee, Yueh Lin; Shao-Horn, Yang

2015-01-01

Perovskite oxides (ABO[subscript 3]) have been studied extensively to promote the kinetics of the oxygen evolution reaction (OER) in alkaline electrolytes. However, developing highly active catalysts for OER at near-neutral pH is desirable for many photoelectrochemical/electrochemical devices. In this paper, we systematically studied the activity and stability of well-known perovskite oxides for OER at pH 7. Previous activity descriptors established for perovskite oxides at pH 13, such as hav...

Perancangan dan Analisis Redistribution Routing Protocol OSPF dan EIGRP

Directory of Open Access Journals (Sweden)

DWI ARYANTA

2014-07-01

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 and metric compared with the simulation results. The result can be OSPF and EIGRP redistribution process. Value delay redistribution 1% better than OSPF and EIGRP 2-3% under traffic density dependent. In calculating the trace route redistribution is done 2 calculations, the cost for OSPF area and the area of the EIGRP metric. Making primary and alternate paths based on the packet delivery rate and the cost of the smallest metric, it is proved by calculation and simulation. Keywords: OSPF, EIGRP, Redistribution, Delay, Cost, Metric.

Analyzing multiday route choice behavior of commuters using GPS data

Directory of Open Access Journals (Sweden)

Wenyun Tang

2016-02-01

Full Text Available In this study, accurate global position system and geographic information system data were employed to reveal multiday routes people used and to study multiday route choice behavior for the same origin–destination trips, from home to work. A new way of thinking about route choice modeling is provided in this study. Travelers are classified into three kinds based on the deviation between actual routes and the shortest travel time paths. Based on the classification, a two-stage route choice process is proposed, in which the first step is to classify the travelers and the second one is to model route choice behavior. After analyzing the characteristics of different types of travelers, an artificial neural network was adopted to classify travelers and model route choice behavior. An empirical study using global position systems data collected in Minneapolis–St Paul metropolitan area was carried out. It finds that most travelers follow the same route during commute trips on successive days. And different types of travelers have a significant difference in route choice property. The modeling results indicate that neural network framework can classify travelers and model route choice well.

Route assessment using comparative risk factors integrated through a GIS

International Nuclear Information System (INIS)

Toth, D.M.; O'Connell, W.J.

1996-01-01

The assessment of potential alternative routes for the shipment of spent nuclear fuel was simplified through the use of comparative risk factors evaluated using detailed route and environmental attributes. The route characteristics, integrated into risk measures, vary strongly with location and were developed from national, state, and local sources. The route data and evaluation were managed using a geographic information system (GIS). An assessment of four real North Florida routes was performed and an interstate highway route exhibited the lowest risk based on the application of the risk factors

Routing in Wireless Multimedia Home Networks

NARCIS (Netherlands)

Scholten, Johan; Jansen, P.G.; Hop, Laurens

This paper describes an adapted version of the destination sequenced distance vector routing protocol (DSDV) which is suitable to calculate routes in a wireless ¿real-time¿ home network. The home network is based on a IEEE 802.11b ad hoc network and uses a scheduled token to enforce real-time

Cost analysis of hybrid adaptive routing protocol for heterogeneous ...

Indian Academy of Sciences (India)

NONITA SHARMA

Event detection; wireless sensor networks; hybrid routing; cost benefit analysis; proactive routing; reactive routing. 1. ... additional energy, high processing power, etc. are deployed to extend the .... transmit to its parent node. (2) Reactive ...

A joint routing and speed optimization problem

OpenAIRE

Fukasawa, Ricardo; He, Qie; Santos, Fernando; Song, Yongjia

2016-01-01

Fuel cost contributes to a significant portion of operating cost in cargo transportation. Though classic routing models usually treat fuel cost as input data, fuel consumption heavily depends on the travel speed, which has led to the study of optimizing speeds over a given fixed route. In this paper, we propose a joint routing and speed optimization problem to minimize the total cost, which includes the fuel consumption cost. The only assumption made on the dependence between the fuel cost an...

Suppressing traffic-driven epidemic spreading by adaptive routing strategy

International Nuclear Information System (INIS)

Yang, Han-Xin; Wang, Zhen

2016-01-01

The design of routing strategies for traffic-driven epidemic spreading has received increasing attention in recent years. In this paper, we propose an adaptive routing strategy that incorporates topological distance with local epidemic information through a tunable parameter h. In the case where the traffic is free of congestion, there exists an optimal value of routing parameter h, leading to the maximal epidemic threshold. This means that epidemic spreading can be more effectively controlled by adaptive routing, compared to that of the static shortest path routing scheme. Besides, we find that the optimal value of h can greatly relieve the traffic congestion in the case of finite node-delivering capacity. We expect our work to provide new insights into the effects of dynamic routings on traffic-driven epidemic spreading.

Penerapan Algoritma Genetika Untuk Penyelesaian Vehicle Routing Problem With Delivery And Pick-Up (VRP-DP)

OpenAIRE

Simanullang, Herlin

2013-01-01

Vehicle Routing Problem (VRP) is a problem of combinatorial optimization complexeses that has essential role in management distribution system which is aimed to minimize the needed cost, the cost is determined in relationship with the distance of route which is taken by the distribution vehicle. The characteristic from VRP is the use of vehicle in certain capacity and its activity is centralized in one depot to serve the customer on certain locations with certain known demand. ...

Evolution of fractality in space plasmas of interest to geomagnetic activity

Science.gov (United States)

Muñoz, Víctor; Domínguez, Macarena; Alejandro Valdivia, Juan; Good, Simon; Nigro, Giuseppina; Carbone, Vincenzo

2018-03-01

We studied the temporal evolution of fractality for geomagnetic activity, by calculating fractal dimensions from the Dst data and from a magnetohydrodynamic shell model for turbulent magnetized plasma, which may be a useful model to study geomagnetic activity under solar wind forcing. We show that the shell model is able to reproduce the relationship between the fractal dimension and the occurrence of dissipative events, but only in a certain region of viscosity and resistivity values. We also present preliminary results of the application of these ideas to the study of the magnetic field time series in the solar wind during magnetic clouds, which suggest that it is possible, by means of the fractal dimension, to characterize the complexity of the magnetic cloud structure.

Satellite network robust QoS-aware routing

CERN Document Server

Long, Fei

2014-01-01

Satellite Network Robust QoS-aware Routing presents a novel routing strategy for satellite networks. This strategy is useful for the design of multi-layered satellite networks as it can greatly reduce the number of time slots in one system cycle. The traffic prediction and engineering approaches make the system robust so that the traffic spikes can be handled effectively. The multi-QoS optimization routing algorithm can satisfy various potential user requirements. Clear and sufficient illustrations are also presented in the book. As the chapters cover the above topics independently, readers from different research backgrounds in constellation design, multi-QoS routing, and traffic engineering can benefit from the book.   Fei Long is a senior engineer at Beijing R&D Center of 54th Research Institute of China Electronics Technology Group Corporation.

CHEMICAL EVOLUTION

Energy Technology Data Exchange (ETDEWEB)

Calvin, Melvin

1965-06-01

How did life come to be on the surface of the earth? Darwin himself recognized that his basic idea of evolution by variation and natural selection must be a continuous process extending backward in time through that period in which the first living things arose and into the period of 'Chemical Evolution' which preceded it. We are approaching the examination of these events by two routes. One is to seek for evidence in the ancient rocks of the earth which were laid down prior to that time in which organisms capable of leaving their skeletons in the rocks to be fossilized were in existence. This period is sometime prior to approximately 600 million years ago. The earth is believed to have taken its present form approximately 4700 million years ago. We have found in rocks whose age is about 1000 million years certain organic molecules which are closely related to the green pigment of plants, chlorophyll. This seems to establish that green plants were already fluorishing prior to that time. We have now found in rocks of still greater age, namely, 2500 million years, the same kinds of molecules mentioned above which can be attributed to the presence of living organisms. If these molecules are as old as the rocks, we have thus shortened the time available for the generation of the complex biosynthetic sequences which give rise to these specific hydrocarbons (polyisoprenoids) to less than 2000 million years.

An inventory location routing model with environmental considerations

Directory of Open Access Journals (Sweden)

Lerhlaly Sanaa

2017-01-01

Full Text Available In this work we consider an integrated Inventory Location Routing problem ILRP. The objective is to select depots to open, the routes to perform distribution from the capacitated depots to the clients by a homogeneous fleet of vehicles and over a multi-period planning horizon. To solve the problem, an exact model is designed in order to minimize the total cost (location, routing and inventory and the routing CO2 emissions, while respecting transport and storage constraints for a hazardous material. We have also studied an industrial real case to illustrate the problem.

Cathodic electrochemical activation of Co3O4 nanoarrays: a smart strategy to significantly boost the hydrogen evolution activity.

Science.gov (United States)

Yang, Li; Zhou, Huang; Qin, Xin; Guo, Xiaodong; Cui, Guanwei; Asiri, Abdullah M; Sun, Xuping

2018-02-22

Co(hydro)oxides show unsatisfactory catalytic activity for the hydrogen evolution reaction (HER) in alkaline media, and it is thus highly desirable but still remains a challenge to design and develop Co(hydro)oxide derived materials as superb hydrogen-evolving catalysts using a facile, rapid and less energy-intensive method. Here, we propose a cathodic electrochemical activation strategy toward greatly boosted HER activity of a Co 3 O 4 nanoarray via room-temperature cathodic polarization in sodium hypophosphite solution. After activation, the overpotential significantly decreases from 260 to 73 mV to drive a geometrical catalytic current density of 10 mA cm -2 in 1.0 M KOH. Notably, this activated electrode also shows strong long-term electrochemical durability with the retention of its catalytic activity at 100 mA cm -2 for at least 40 h.

Path Diversity Improved Opportunistic Routing for Underwater Sensor Networks.

Science.gov (United States)

Bai, Weigang; Wang, Haiyan; He, Ke; Zhao, Ruiqin

2018-04-23

The packets carried along a pre-defined route in underwater sensor networks are very vulnerble. Node mobility or intermittent channel availability easily leads to unreachable routing. Opportunistic routing has been proven to be a promising paradigm to design routing protocols for underwater sensor networks. It takes advantage of the broadcast nature of the wireless medium to combat packet losses and selects potential paths on the fly. Finding an appropriate forwarding candidate set is a key issue in opportunistic routing. Many existing solutions ignore the impact of candidates location distribution on packet forwarding. In this paper, a path diversity improved candidate selection strategy is applied in opportunistic routing to improve packet forwarding efficiency. It not only maximizes the packet forwarding advancements but also takes the candidate’s location distribution into account. Based on this strategy, we propose two effective routing protocols: position improved candidates selection (PICS) and position random candidates selection (PRCS). PICS employs two-hop neighbor information to make routing decisions. PRCS only uses one-hop neighbor information. Simulation results show that both PICS and PRCS can significantly improve network performance when compared with the previous solutions, in terms of packet delivery ratio, average energy consumption and end-to-end delay.

Path Diversity Improved Opportunistic Routing for Underwater Sensor Networks

Directory of Open Access Journals (Sweden)

Weigang Bai

2018-04-01

Full Text Available The packets carried along a pre-defined route in underwater sensor networks are very vulnerble. Node mobility or intermittent channel availability easily leads to unreachable routing. Opportunistic routing has been proven to be a promising paradigm to design routing protocols for underwater sensor networks. It takes advantage of the broadcast nature of the wireless medium to combat packet losses and selects potential paths on the fly. Finding an appropriate forwarding candidate set is a key issue in opportunistic routing. Many existing solutions ignore the impact of candidates location distribution on packet forwarding. In this paper, a path diversity improved candidate selection strategy is applied in opportunistic routing to improve packet forwarding efficiency. It not only maximizes the packet forwarding advancements but also takes the candidate’s location distribution into account. Based on this strategy, we propose two effective routing protocols: position improved candidates selection (PICS and position random candidates selection (PRCS. PICS employs two-hop neighbor information to make routing decisions. PRCS only uses one-hop neighbor information. Simulation results show that both PICS and PRCS can significantly improve network performance when compared with the previous solutions, in terms of packet delivery ratio, average energy consumption and end-to-end delay.

Widely available active sites on Ni2P for electrochemical hydrogen evolution - insights from first principles calculations

DEFF Research Database (Denmark)

Hansen, Martin Hangaard; Stern, Lucas-Alexandre; Feng, Ligang

2015-01-01

We present insights into the mechanism and the active site for hydrogen evolution on nickel phosphide (Ni2P). Ni2P was recently discovered to be a very active non-precious hydrogen evolution catalyst. Current literature attributes the activity of Ni2P to a particular site on the (0001) facet....... In the present study, using Density Functional Theory (DFT) calculations, we show that several widely available low index crystal facets on Ni2P have better properties for a high catalytic activity. DFT calculations were used to identify moderately bonding nickel bridge sites and nickel hollow sites for hydrogen...... adsorption and to calculate barriers for the Tafel pathway. The investigated surfaces in this study were the (10 (1) over bar0), ((1) over bar(1) over bar 20), (11 (2) over bar0), (11 (2) over bar1) and (0001) facets of the hexagonal Ni2P crystal. In addition to the DFT results, we present experiments on Ni2...

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

Intermediate and high level processing operations are performed on vision data for the organization of images into more meaningful, higher-level topological representations by means of a region-based route planner (RBRP). The RBRP operates in terrain scenarios where some or most of the terrain is occluded, proceeding without a priori maps on the basis of two-dimensional representations and gradient-and-roughness information. Route planning is accomplished by three successive abstractions and yields a detailed point-by-point path by searching only within the boundaries of relatively small regions.

Transportation of radioactive materials routing analysis: The Nevada experience

International Nuclear Information System (INIS)

Ardila-Coulson, M.V.

1991-01-01

In 1987, the Nevada State Legislature passed a Bill requiring the Nevada Dept. of Transportation to develop and enforce a plan for highway routing of highway route controlled quantity shipments of radioactive materials and high-level radioactive waste. A large network with all the major highways in Nevada was created and used in a computer model developed by Sandia National Labs. Twenty-eight highway parameters that included geometrics, traffic characteristics, environment and special facilities were collected. Alternative routes were identified by minimizing primary parameters (population density and accident rates). An analysis using the US DOT Guidelines were performed to identify a preferred route from the alternative routes

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.

Routing strategies in traffic network and phase transition in network ...

Indian Academy of Sciences (India)

The dynamics of information traffic over scale-free networks has been investigated systematically. A series of routing strategies of data packets have been proposed, including the local routing strategy, the next-nearest-neighbour routing strategy, and the mixed routing strategy based on local static and dynamic information.

Routing protocols for wireless sensor networks: What the literature says?

Directory of Open Access Journals (Sweden)

Amit Sarkar

2016-12-01

Full Text Available Routing in Wireless Sensor Networks (WSNs plays a significant role in the field of environment-oriented monitoring, traffic monitoring, etc. Here, wide contributions that are made toward routing in WSN are explored. The paper mainly aims to categorize the routing problems and examines the routing-related optimization problems. For achieving the motive, 50 papers from the standard journals are collected and primarily reviewed in a chronological way. Later, various features that are related to energy, security, speed and reliability problems of routing are discussed. Subsequently, the literature is analyzed based on the simulation environment and experimental setup, awareness over the Quality of Service (QoS and the deployment against various applications. In addition, the optimization of the routing algorithms and the meta-heuristic study of routing optimization are explored. Routing is a vast area with numerous unsolved issues and hence, various research gaps along with future directions are also presented.

Identification of degradation routes of metamitron in soil microcosms using 13C-isotope labeling.

Science.gov (United States)

Wang, Shizong; Miltner, Anja; Nowak, Karolina M

2017-01-01

Metamitron is one of the most commonly used herbicide in sugar beet and flower bulb cultures. Numerous laboratory and field studies on sorption and degradation of metamitron were performed. Detailed biodegradation studies in soil using 13 C-isotope labeling are still missing. Therefore, we aimed at providing a detailed turnover mass balance of 13 C 6 -metamitron in soil microcosms over 80 days. In the biotic system, metamitron mineralized rapidly, and 13 CO 2 finally constituted 60% of the initial 13 C 6 -metamitron equivalents. In abiotic control experiments CO 2 rose to only 7.4% of the initial 13 C 6 -metamitron equivalents. The 13 C label from 13 C 6 -metamitron was incorporated into microbial amino acids that were ultimately stabilized in the soil organic matter forming presumably harmless biogenic residues. Finally, 13 C label from 13 C 6 -metamitron was distributed between the 13 CO 2 and the 13 C-biogenic residues indicating nearly complete biodegradation. The parallel increase of 13 C-alanine, 13 C-glutamate and 13 CO 2 indicates that metamitron was initially biodegraded via the desamino-metamitron route suggesting its relevance in the growth metabolism. In later phases of biodegradation, the "Rhodococcus route" was indicated by the low 13 CO 2 evolution and the high relevance of the pyruvate pathway, which aims at biomolecule synthesis and seems to be related to starvation. This is a first report on the detailed degradation route of metamitron in soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Enhancing Activity for the Oxygen Evolution Reaction

DEFF Research Database (Denmark)

Frydendal, Rasmus; Busch, Michael; Halck, Niels Bendtsen

2014-01-01

Electrochemical production of hydrogen, facilitated in electrolyzers, holds great promise for energy storage and solar fuel production. A bottleneck in the process is the catalysis of the oxygen evolution reaction, involving the transfer of four electrons. The challenge is that the binding energies...... of all reaction intermediates cannot be optimized individually. However, experimental investigations have shown that drastic improvements can be realized for manganese and cobalt-based oxides if gold is added to the surface or used as substrate. We propose an explanation for these enhancements based...... that the oxygen evolution reaction overpotential decreases by 100–300 mV for manganese oxides and 100 mV for cobalt oxides....

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.

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)

Privacy-Preserving Interdomain Routing at Internet Scale

Directory of Open Access Journals (Sweden)

Asharov Gilad

2017-07-01

Full Text Available The Border Gateway Protocol (BGP computes routes between the organizational networks that make up today’s Internet. Unfortunately, BGP suffers from deficiencies, including slow convergence, security problems, a lack of innovation, and the leakage of sensitive information about domains’ routing preferences. To overcome some of these problems, we revisit the idea of centralizing and using secure multi-party computation (MPC for interdomain routing which was proposed by Gupta et al. (ACM HotNets’12. We implement two algorithms for interdomain routing with state-of-the-art MPC protocols. On an empirically derived dataset that approximates the topology of today’s Internet (55 809 nodes, our protocols take as little as 6 s of topology-independent precomputation and only 3 s of online time. We show, moreover, that when our MPC approach is applied at country/region-level scale, runtimes can be as low as 0.17 s online time and 0.20 s pre-computation time. Our results motivate the MPC approach for interdomain routing and furthermore demonstrate that current MPC techniques are capable of efficiently tackling real-world problems at a large scale.

Emission control with route optimization in solid waste collection ...

Indian Academy of Sciences (India)

system is used, route distance and route time will be decreased by 24·6% and. 44·3% as ... Keywords. Exhaust emission; route optimization; solid waste collection; GIS, .... Catchment areas for a sales campaign can be analysed. Customers ...

Benefits Analysis of Multi-Center Dynamic Weather Routes

Science.gov (United States)

Sheth, Kapil; McNally, David; Morando, Alexander; Clymer, Alexis; Lock, Jennifer; Petersen, Julien

2014-01-01

Dynamic weather routes are flight plan corrections that can provide airborne flights more than user-specified minutes of flying-time savings, compared to their current flight plan. These routes are computed from the aircraft's current location to a flight plan fix downstream (within a predefined limit region), while avoiding forecasted convective weather regions. The Dynamic Weather Routes automation has been continuously running with live air traffic data for a field evaluation at the American Airlines Integrated Operations Center in Fort Worth, TX since July 31, 2012, where flights within the Fort Worth Air Route Traffic Control Center are evaluated for time savings. This paper extends the methodology to all Centers in United States and presents benefits analysis of Dynamic Weather Routes automation, if it was implemented in multiple airspace Centers individually and concurrently. The current computation of dynamic weather routes requires a limit rectangle so that a downstream capture fix can be selected, preventing very large route changes spanning several Centers. In this paper, first, a method of computing a limit polygon (as opposed to a rectangle used for Fort Worth Center) is described for each of the 20 Centers in the National Airspace System. The Future ATM Concepts Evaluation Tool, a nationwide simulation and analysis tool, is used for this purpose. After a comparison of results with the Center-based Dynamic Weather Routes automation in Fort Worth Center, results are presented for 11 Centers in the contiguous United States. These Centers are generally most impacted by convective weather. A breakdown of individual Center and airline savings is presented and the results indicate an overall average savings of about 10 minutes of flying time are obtained per flight.

Victim derogation and victim enhancement as alternate routes to system justification.

Science.gov (United States)

Kay, Aaron C; Jost, John T; Young, Sean

2005-03-01

Abstract-Numerous studies have documented the potential for victim-blaming attributions to justify the status quo. Recent work suggests that complementary, victim-enhancing stereotypes may also increase support for existing social arrangements. We seek to reconcile these seemingly contradictory findings by proposing that victim derogation and victim enhancement are alternate routes to system justification, with the preferred route depending on the perception of a causal link between trait and outcome. Derogating "losers" (and lionizing "winners") on traits (e.g., intelligence) that are causally related to outcomes (e.g., wealth vs. poverty) serves to increase system justification, as does compensating "losers" (and downgrading "winners") on traits (e.g., physical attractiveness) that are causally unrelated to those outcomes. We provide converging evidence using system-threat and stereotype-activation paradigms.

XRD and 119Sn Moessbauer spectroscopy characterization of SnSe obtained from a simple chemical route

International Nuclear Information System (INIS)

Bernardes-Silva, Ana Claudia; Mesquita, A.F.; Moura de Neto, E.; Porto, A.O.; Ardisson, J.D.; Lima, G.M. de; Lameiras, F.S.

2005-01-01

Crystalline tin selenide semiconductor was synthesized by a chemical route. Selenium powder reacted with potassium boronhydride, giving a soluble selenium species potassium seleniumhydride. The reaction of potassium seleniumhydride with tin chloride produced crystalline tin selenide, which was characterized by X-ray diffraction, 119 Sn Moessbauer spectroscopy and scanning electronic microscopy. The material was thermally treated, in nitrogen flow, at 300 and 600 deg. C for 2 h and the particle size evolution was studied by X-ray diffraction. The X-ray diffraction and 119 Sn Moessbauer results showed that a mixture of tin oxides and orthorhombic tin selenide was obtained

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 ...

On the vehicle routing problem with time windows

DEFF Research Database (Denmark)

Kallehauge, Brian

2006-01-01

. The fourth and final paper ‘Vehicle routing problem with time windows’ (Kallehauge, Larsen, Madsen, and Solomon. In Desaulniers, Desrosiers, and Solomon, editors, Column generation, pages 67-98, Springer, New York, 2005) is a contribution to a book on column generation edited by G. Desaulniers, J. Desrosiers......The vehicle routing problem with time windows is concerned with the optimal routing of a fleet of vehicles between a depot and a number of customers that must be visited within a specified time interval, called a time window. The purpose of this thesis is to develop new and efficient solution...... techniques for solving the vehicle routing problem with time windows (VRPTW). The thesis consists of a section of introductory remarks and four independent papers. The first paper ‘Formulations and exact approaches for the vehicle routing problem with time windows’ (Kallehauge, 2005, unpublished) is a review...

Improved Efficient Routing Strategy on Scale-Free Networks

Science.gov (United States)

Jiang, Zhong-Yuan; Liang, Man-Gui

Since the betweenness of nodes in complex networks can theoretically represent the traffic load of nodes under the currently used routing strategy, we propose an improved efficient (IE) routing strategy to enhance to the network traffic capacity based on the betweenness centrality. Any node with the highest betweenness is susceptible to traffic congestion. An efficient way to improve the network traffic capacity is to redistribute the heavy traffic load from these central nodes to non-central nodes, so in this paper, we firstly give a path cost function by considering the sum of node betweenness with a tunable parameter β along the actual path. Then, by minimizing the path cost, our IE routing strategy achieved obvious improvement on the network transport efficiency. Simulations on scale-free Barabási-Albert (BA) networks confirmed the effectiveness of our strategy, when compared with the efficient routing (ER) and the shortest path (SP) routing.

Routing Optimization of Intelligent Vehicle in Automated Warehouse

Directory of Open Access Journals (Sweden)

Yan-cong Zhou

2014-01-01

Full Text Available Routing optimization is a key technology in the intelligent warehouse logistics. In order to get an optimal route for warehouse intelligent vehicle, routing optimization in complex global dynamic environment is studied. A new evolutionary ant colony algorithm based on RFID and knowledge-refinement is proposed. The new algorithm gets environmental information timely through the RFID technology and updates the environment map at the same time. It adopts elite ant kept, fallback, and pheromones limitation adjustment strategy. The current optimal route in population space is optimized based on experiential knowledge. The experimental results show that the new algorithm has higher convergence speed and can jump out the U-type or V-type obstacle traps easily. It can also find the global optimal route or approximate optimal one with higher probability in the complex dynamic environment. The new algorithm is proved feasible and effective by simulation results.

OSM-ORIENTED METHOD OF MULTIMODAL ROUTE PLANNING

Directory of Open Access Journals (Sweden)

X. Li

2015-07-01

Full Text Available With the increasing pervasiveness of basic facilitate of transportation and information, the need of multimodal route planning is becoming more essential in the fields of communication and transportation, urban planning, logistics management, etc. This article mainly described an OSM-oriented method of multimodal route planning. Firstly, it introduced how to extract the information we need from OSM data and build proper network model and storage model; then it analysed the accustomed cost standard adopted by most travellers; finally, we used shortest path algorithm to calculate the best route with multiple traffic means.

Multifactor-Driven Hierarchical Routing on Enterprise Service Bus

Science.gov (United States)

Mi, Xueqiang; Tang, Xinhuai; Yuan, Xiaozhou; Chen, Delai; Luo, Xiangfeng

Message Routing is the foremost functionality on Enterprise Service Bus (ESB), but current ESB products don't provide an expected solution for it, especially in the aspects of runtime route change mechanism and service orchestration model. In order to solve the above drawbacks, this paper proposes a multifactor-driven hierarchical routing (MDHR) model. MDHR defines three layers for message routing on ESB. Message layer gives the original support for message delivery. Application layer can integration or encapsulate some legacy applications or un-standard services. Business layer introduces business model to supplies developers with a business rule configuration, which supports enterprise integration patterns and simplifies the service orchestration on ESB.

TWO-DIMENSIONAL CELLULAR AUTOMATON MODEL FOR THE EVOLUTION OF ACTIVE REGION CORONAL PLASMAS

Energy Technology Data Exchange (ETDEWEB)

López Fuentes, Marcelo [Instituto de Astronomía y Física del Espacio, CONICET-UBA, CC. 67, Suc. 28, 1428 Buenos Aires (Argentina); Klimchuk, James A., E-mail: lopezf@iafe.uba.ar [NASA Goddard Space Flight Center, Code 671, Greenbelt, MD 20771 (United States)

2015-02-01

We study a two-dimensional cellular automaton (CA) model for the evolution of coronal loop plasmas. The model is based on the idea that coronal loops are made of elementary magnetic strands that are tangled and stressed by the displacement of their footpoints by photospheric motions. The magnetic stress accumulated between neighbor strands is released in sudden reconnection events or nanoflares that heat the plasma. We combine the CA model with the Enthalpy Based Thermal Evolution of Loops model to compute the response of the plasma to the heating events. Using the known response of the X-Ray Telescope on board Hinode, we also obtain synthetic data. The model obeys easy-to-understand scaling laws relating the output (nanoflare energy, temperature, density, intensity) to the input parameters (field strength, strand length, critical misalignment angle). The nanoflares have a power-law distribution with a universal slope of –2.5, independent of the input parameters. The repetition frequency of nanoflares, expressed in terms of the plasma cooling time, increases with strand length. We discuss the implications of our results for the problem of heating and evolution of active region coronal plasmas.

A Survey of Routing Protocols in Wireless Body Sensor Networks

Science.gov (United States)

Bangash, Javed Iqbal; Abdullah, Abdul Hanan; Anisi, Mohammad Hossein; Khan, Abdul Waheed

2014-01-01

Wireless Body Sensor Networks (WBSNs) constitute a subset of Wireless Sensor Networks (WSNs) responsible for monitoring vital sign-related data of patients and accordingly route this data towards a sink. In routing sensed data towards sinks, WBSNs face some of the same routing challenges as general WSNs, but the unique requirements of WBSNs impose some more constraints that need to be addressed by the routing mechanisms. This paper identifies various issues and challenges in pursuit of effective routing in WBSNs. Furthermore, it provides a detailed literature review of the various existing routing protocols used in the WBSN domain by discussing their strengths and weaknesses. PMID:24419163

Exploring en-route parking type and parking-search route choice

DEFF Research Database (Denmark)

Kaplan, Sigal; Bekhor, Sholomo

2011-01-01

This paper describes the first phase of an on-going research investigating the joint choice of parking type, parking facility and cruising-for-parking route. The importance of this issue derives from the significant share of cruising-for-parking traffic in urban areas, the relevance of parking po...

The non-peptide CRH1-antagonist CP-154,526 elicits a paradoxical route-dependent activation of the HPA axis.

Science.gov (United States)

Zaretsky, Dmitry V; Zaretskaia, Maria V; Sarkar, Sumit; Rusyniak, Daniel E; DiMicco, Joseph A

2017-07-13

The corticotropin-releasing hormone (CRH) plays an important role in mediating physiological response to stress and is thought to be involved in the development of various psychiatric disorders. In this paper, we compare the differences between the effect of intraperitoneal (i.p.) and intraarterial (i.a.) administration of the non-peptide CRH 1 antagonist CP-154,526 (CP) (10 and 20mg/kg) on plasma adrenocorticotropic hormone levels (ACTH), heart rate, MAP, and c-Fos expression in the paraventricular nucleus of the hypothalamus. Intraperitoneal, but not i.a., injection of CP resulted in an increase in plasma ACTH (from 105±13 to 278±51pg/ml after 20mg/kg). This effect was accompanied by a dramatic increase in c-Fos expression in cells immunoreactive for CRH in the paraventricular nucleus of the hypothalamus. When the drug was administered i.p., CP-induced activation of the HPA appears to mask the inhibitory effect of CP on stress-induced ACTH secretion, an effect which was readily apparent when the drug was given i.a. Intraperitoneal administration of CP also increased the baseline MAP which may account for previous reports that treatment with this drug attenuated the increases associated with stress. CP given by either route had no effect on baseline heart rate or stress-induced tachycardia. Thus, in all studies in which CP 154,526 is given, the route of delivery must be given careful consideration. Copyright © 2017 Elsevier B.V. All rights reserved.

A High-Resolution Study of Hippocampal and Medial Temporal Lobe Correlates of Spatial Context and Prospective Overlapping Route Memory

Science.gov (United States)

Brown, Thackery I.; Hasselmo, Michael E.; Stern, Chantal E.

2015-01-01

When navigating our world we often first plan or retrieve an ideal route to our goal, avoiding alternative paths that lead to other destinations. The medial temporal lobe (MTL) has been implicated in processing contextual information, sequence memory, and uniquely retrieving routes that overlap or “cross paths.” However, the identity of subregions of the hippocampus and neighboring cortex that support these functions in humans remains unclear. The present study used high-resolution functional magnetic resonance imaging (hr-fMRI) in humans to test whether the CA3/DG hippocampal subfield and para-hippocampal cortex are important for processing spatial context and route retrieval, and whether the CA1 subfield facilitates prospective planning of mazes that must be distinguished from alternative overlapping routes. During hr-fMRI scanning, participants navigated virtual mazes that were well-learned from prior training while also learning new mazes. Some routes learned during scanning shared hallways with those learned during pre-scan training, requiring participants to select between alternative paths. Critically, each maze began with a distinct spatial contextual Cue period. Our analysis targeted activity from the Cue period, during which participants identified the current navigational episode, facilitating retrieval of upcoming route components and distinguishing mazes that overlap. Results demonstrated that multiple MTL regions were predominantly active for the contextual Cue period of the task, with specific regions of CA3/DG, parahippocampal cortex, and perirhinal cortex being consistently recruited across trials for Cue periods of both novel and familiar mazes. During early trials of the task, both CA3/DG and CA1 were more active for overlapping than non-overlapping Cue periods. Trial-by-trial Cue period responses in CA1 tracked subsequent overlapping maze performance across runs. Together, our findings provide novel insight into the contributions of MTL

Applications of RADTRAN 4 to route-specific analysis

International Nuclear Information System (INIS)

Neuhauser, Sieglinde; Weiner, Ruth F.

1992-01-01

The transportation risk evaluation code RADTRAN 4 is designed to evaluate doses and risks associated with the transportation of radioactive materials. RADTRAN 4 may be used to calculate dose consequences for incident- free transportation and dose risks for accidents. Consequences of normal (or incident-free) transportation include doses to crew members, persons at stops, and members of the public sharing a route segment (on-link) and residing near the segment (off-link) during normal transportation. These dose estimates are not multiplied by a probability factor and, hence, are referred to as dose consequences. Calculated doses that might be incurred during accidents arc multiplied by the probabilities of those accidents, and hence are referred to as dose risks. RADTRAN 4 includes a LINK option that allows the user to characterize each link or segment of a transportation route in greater detail than that provided by average or default values for route-related parameters. The LINK option increases the flexibility of the code in several ways: LINK allows the same route segment to be evaluated under a variety of conditions. This capability may be used to prepare environmental documentation and to evaluate alternative routes under V.S. Department of Transportation Docket HM-164 (49 CFR 171-177); LINK capability may be used to assess the impact of projected population shifts on transportation routes; LINK facilitates comparison of the national average data included as defaults in RADTRAN with available 'route-specific' data. (author)

How to enhance route learning and visuo-spatial working memory in aging: a training for residential care home residents.

Science.gov (United States)

Mitolo, Micaela; Borella, Erika; Meneghetti, Chiara; Carbone, Elena; Pazzaglia, Francesca

2017-05-01

This study aimed to assess the efficacy of a route-learning training in a group of older adults living in a residential care home. We verified the presence of training-specific effects in tasks similar to those trained - route-learning tasks - as well as transfer effects on related cognitive processes - visuo-spatial short-term memory (VSSTM; Corsi Blocks Test (CBT), forward version), visuo-spatial working memory (VSWM; CBT, backward version; Pathway Span Tasks; Jigsaw Puzzle Test) - and in self-report measures. The maintenance of training benefits was examined after 3 months. Thirty 70-90-year-old residential care home residents were randomly assigned to the route-learning training group or to an active control group (involved in non-visuo-spatial activities). The trained group performed better than the control group in the route-learning tasks, retaining this benefit 3 months later. Immediate transfer effects were also seen in visuo-spatial span tasks (i.e., CBT forward and backward version and Pathway Span Task); these benefits had been substantially maintained at the 3-month follow-up. These findings suggest that a training on route learning is a promising approach to sustain older adults' environmental learning and some related abilities (e.g., VSSTM and VSWM), even in residential care home residents.

Link reliability based hybrid routing for tactical mobile ad hoc network

Institute of Scientific and Technical Information of China (English)

Xie Xiaochuan; Wei Gang; Wu Keping; Wang Gang; Jia Shilou

2008-01-01

Tactical mobile ad hoc network (MANET) is a collection of mobile nodes forming a temporary network,without the aid of pre-established network infrastructure. The routing protocol has a crucial impact on the networkperformance in battlefields. Link reliability based hybrid routing (LRHR) is proposed, which is a novel hybrid routing protocol, for tactical MANET. Contrary to the traditional single path routing strategy, multiple paths are established between a pair of source-destination nodes. In the hybrid routing strategy, the rate of topological change provides a natural mechanism for switching dynamically between table-driven and on-demand routing. The simulation results indicate that the performances of the protocol in packet delivery ratio, routing overhead, and average end-to-end delay are better than the conventional routing protocol.

Relief Evolution in Tectonically Active Mountain Ranges

Science.gov (United States)

Whipple, Kelin X.

2004-01-01

The overall aims of this 3-yr project, as originally proposed were to: (1) investigate quantitatively the roles of fluvial and glacial erosion in the evolution of relief in mountainous regions, and (2) test rigorously the quality and accuracy of SRTM topographic data in areas of rugged relief - both the most challenging and of greatest interest to geomorphic, neotectonic, and hazards applications. Natural laboratories in both the western US and the Southern Alps of New Zealand were identified as most promising. The project has been both successful and productive, despite the fact that no SRTM data for our primary field sites in New Zealand were released on the time frame of the work effort. Given the delayed release of SRTM data, we pursued the scientific questions of the roles of fluvial and, especially, glacial erosion in the evolution of relief in mountainous regions using available digital elevation models (DEMs) for the Southern Alps of New Zealand (available at both 25m and 50m pixel sizes), and USGS 10m and 30m DEMs within the Western US. As emphasized in the original proposal, we chose the emphasis on the role of glacial modification of topographic relief because there has been little quantitative investigation of glacial erosion processes at landscape scale. This is particularly surprising considering the dramatic sculpting of most mid- and high-latitude mountain ranges, the prodigious quantities of glacially-derived sediment in terrestrial and marine basins, and the current cross-disciplinary interest in the role of denudational processes in orogenesis and the evolution of topography in general. Moreover, the evolution of glaciated landscapes is not only a fundamental problem in geomorphology in its own right, but also is at the heart of the debate over Late Cenozoic linkages between climate and tectonics.

OSPF-TE Extensions for Green Routing in Optical Networks

DEFF Research Database (Denmark)

Wang, Jiayuan; Ricciardi, S.; Fagertun, Anna Manolova

2012-01-01

This paper proposes extensions to the OSPF-TE protocol to enable green routing in GMPLS-controlled optical networks. Simulation results show a remarkable reduction in CO2 emissions by preferring network elements powered by green energy sources in the connection routing.......This paper proposes extensions to the OSPF-TE protocol to enable green routing in GMPLS-controlled optical networks. Simulation results show a remarkable reduction in CO2 emissions by preferring network elements powered by green energy sources in the connection routing....

Computer-based route-definition system for peripheral bronchoscopy.

Science.gov (United States)

Graham, Michael W; Gibbs, Jason D; Higgins, William E

2012-04-01

Multi-detector computed tomography (MDCT) scanners produce high-resolution images of the chest. Given a patient's MDCT scan, a physician can use an image-guided intervention system to first plan and later perform bronchoscopy to diagnostic sites situated deep in the lung periphery. An accurate definition of complete routes through the airway tree leading to the diagnostic sites, however, is vital for avoiding navigation errors during image-guided bronchoscopy. We present a system for the robust definition of complete airway routes suitable for image-guided bronchoscopy. The system incorporates both automatic and semiautomatic MDCT analysis methods for this purpose. Using an intuitive graphical user interface, the user invokes automatic analysis on a patient's MDCT scan to produce a series of preliminary routes. Next, the user visually inspects each route and quickly corrects the observed route defects using the built-in semiautomatic methods. Application of the system to a human study for the planning and guidance of peripheral bronchoscopy demonstrates the efficacy of the system.

Simple relationship between the virial-route hypernetted-chain and the compressibility-route Percus-Yevick values of the fourth virial coefficient.

Science.gov (United States)

Santos, Andrés; Manzano, Gema

2010-04-14

As is well known, approximate integral equations for liquids, such as the hypernetted chain (HNC) and Percus-Yevick (PY) theories, are in general thermodynamically inconsistent in the sense that the macroscopic properties obtained from the spatial correlation functions depend on the route followed. In particular, the values of the fourth virial coefficient B(4) predicted by the HNC and PY approximations via the virial route differ from those obtained via the compressibility route. Despite this, it is shown in this paper that the value of B(4) obtained from the virial route in the HNC theory is exactly three halves the value obtained from the compressibility route in the PY theory, irrespective of the interaction potential (whether isotropic or not), the number of components, and the dimensionality of the system. This simple relationship is confirmed in one-component systems by analytical results for the one-dimensional penetrable-square-well model and the three-dimensional penetrable-sphere model, as well as by numerical results for the one-dimensional Lennard-Jones model, the one-dimensional Gaussian core model, and the three-dimensional square-well model.

Deduction of passengers' route choice from smart card data

NARCIS (Netherlands)

Van Der Hurk, Evelien; Kroon, Leo; Maroti, Gabor; Vervest, Peter

2013-01-01

Deducing passengers' route choice from smart card data provides public transport operators the opportunity to evaluate passenger service. Especially in case of disruptions when route choice models may not be valid this is an advantage. This paper proposes a method for deducing the chosen route of

Banyan latex: a facile fuel for the multifunctional properties of MgO nanoparticles prepared via auto ignited combustion route

International Nuclear Information System (INIS)

Anil Kumar, M R; Nagaswarupa, H P; Gurushantha, K; Pratapkumar, C; Prashantha, S C; Shashishekar, T R; Anantharaju, K S; Nagabhushana, H; Sharma, S C; Vidya, Y S; Daruka Prasad, B; Vivek Babu, C S; Vishnu Mahesh, K R

2015-01-01

MgO nanoparticles (MNPs) were prepared by a solution combustion route using banyan tree (BT) latex and glycine as fuels. The powder x-ray diffraction results indicate the formation of a single cubic phase and the crystallite size obtained from transmission electron microscopy was found to be ∼10–15 nm. Scanning electron microscopy result reveals spherical-shaped particles obtained with BT latex. However, in a chemical route, porous and agglomerated particles were obtained. The energy band gap of MNPs obtained using BT latex and a chemical route were found to be in the range 4.85–5.0 eV. Photoluminescence peaks observed at 473, 514, and 588 nm when excited at 433 nm, which were attributed to surface defects. The enhanced photocatalytic activities of spherical MgO were due to smaller crystallite size, higher surface defects, dye sensitization, and capability to reduce the electron–hole pair recombination. Further, green-synthesized MNPs exhibit superior antifungal activity against various plant pathogens. The present studies demonstrated a green engineering route for the synthesis of multifunctional MNPs using BT latex. (paper)

Fast reactor calculational route for Pu burning core design

Energy Technology Data Exchange (ETDEWEB)

Hunter, S. [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

1998-01-01

This document provides a description of a calculational route, used in the Reactor Physics Research Section for sensitivity studies and initial design optimization calculations for fast reactor cores. The main purpose in producing this document was to provide a description of and user guides to the calculational methods, in English, as an aid to any future user of the calculational route who is (like the author) handicapped by a lack of literacy in Japanese. The document also provides for all users a compilation of information on the various parts of the calculational route, all in a single reference. In using the calculational route (to model Pu burning reactors) the author identified a number of areas where an improvement in the modelling of the standard calculational route was warranted. The document includes comments on and explanations of the modelling assumptions in the various calculations. Practical information on the use of the calculational route and the computer systems is also given. (J.P.N.)

Management of Energy Consumption on Cluster Based Routing Protocol for MANET

Science.gov (United States)

Hosseini-Seno, Seyed-Amin; Wan, Tat-Chee; Budiarto, Rahmat; Yamada, Masashi

The usage of light-weight mobile devices is increasing rapidly, leading to demand for more telecommunication services. Consequently, mobile ad hoc networks and their applications have become feasible with the proliferation of light-weight mobile devices. Many protocols have been developed to handle service discovery and routing in ad hoc networks. However, the majority of them did not consider one critical aspect of this type of network, which is the limited of available energy in each node. Cluster Based Routing Protocol (CBRP) is a robust/scalable routing protocol for Mobile Ad hoc Networks (MANETs) and superior to existing protocols such as Ad hoc On-demand Distance Vector (AODV) in terms of throughput and overhead. Therefore, based on this strength, methods to increase the efficiency of energy usage are incorporated into CBRP in this work. In order to increase the stability (in term of life-time) of the network and to decrease the energy consumption of inter-cluster gateway nodes, an Enhanced Gateway Cluster Based Routing Protocol (EGCBRP) is proposed. Three methods have been introduced by EGCBRP as enhancements to the CBRP: improving the election of cluster Heads (CHs) in CBRP which is based on the maximum available energy level, implementing load balancing for inter-cluster traffic using multiple gateways, and implementing sleep state for gateway nodes to further save the energy. Furthermore, we propose an Energy Efficient Cluster Based Routing Protocol (EECBRP) which extends the EGCBRP sleep state concept into all idle member nodes, excluding the active nodes in all clusters. The experiment results show that the EGCBRP decreases the overall energy consumption of the gateway nodes up to 10% and the EECBRP reduces the energy consumption of the member nodes up to 60%, both of which in turn contribute to stabilizing the network.

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.

Ising model for packet routing control

International Nuclear Information System (INIS)

Horiguchi, Tsuyoshi; Takahashi, Hideyuki; Hayashi, Keisuke; Yamaguchi, Chiaki

2004-01-01

For packet routing control in computer networks, we propose an Ising model which is defined in order to express competition among a queue length and a distance from a node with a packet to its destination node. By introducing a dynamics for a mean-field value of an Ising spin, we show by computer simulations that effective control of packet routing through priority links is possible

A Method for Driving Route Predictions Based on Hidden Markov Model

Directory of Open Access Journals (Sweden)

Ning Ye

2015-01-01

Full Text Available We present a driving route prediction method that is based on Hidden Markov Model (HMM. This method can accurately predict a vehicle’s entire route as early in a trip’s lifetime as possible without inputting origins and destinations beforehand. Firstly, we propose the route recommendation system architecture, where route predictions play important role in the system. Secondly, we define a road network model, normalize each of driving routes in the rectangular coordinate system, and build the HMM to make preparation for route predictions using a method of training set extension based on K-means++ and the add-one (Laplace smoothing technique. Thirdly, we present the route prediction algorithm. Finally, the experimental results of the effectiveness of the route predictions that is based on HMM are shown.

A Cross-Layer Route Discovery Framework for Mobile Ad Hoc Networks

Directory of Open Access Journals (Sweden)

Wu Jieyi

2005-01-01

Full Text Available Most reactive routing protocols in MANETs employ a random delay between rebroadcasting route requests (RREQ in order to avoid "broadcast storms." However this can lead to problems such as "next hop racing" and "rebroadcast redundancy." In addition to this, existing routing protocols for MANETs usually take a single routing strategy for all flows. This may lead to inefficient use of resources. In this paper we propose a cross-layer route discovery framework (CRDF to address these problems by exploiting the cross-layer information. CRDF solves the above problems efficiently and enables a new technique: routing strategy automation (RoSAuto. RoSAuto refers to the technique that each source node automatically decides the routing strategy based on the application requirements and each intermediate node further adapts the routing strategy so that the network resource usage can be optimized. To demonstrate the effectiveness and the efficiency of CRDF, we design and evaluate a macrobian route discovery strategy under CRDF.

Proxies for Anonymous Routing

National Research Council Canada - National Science Library

Reed, Michael G; Syverson, Paul F; Goldschlag, David M

1996-01-01

...), and file transfers (FTP) have been implemented. Onion routing provides application independent, real-time, and bi-directional anonymous connections that are resistant to both eavesdropping and traffic analysis...

Route planning module as a part of Supply Chain Management system

Directory of Open Access Journals (Sweden)

Michal Košíček

2012-01-01

Full Text Available Today, the demand for creating a systematic approach for managing sales, ordering, and logistics has increased. Supply Chain Management (SCM is one of the responses to problems that have arose with the need for managing complex supply chains. Nowadays, most of the activities of Supply Chain Management is realized or supported with computing technologies. Route planning is an important part of Supply Chain Management related to both procurement and distribution. Route planning systems specify the sequences in which the selected transport vehicles should supply the demand points by requested quantities of goods at the right time. The paper is focused on the analysis of a route planning system which could be used as a part of Supply Chain Management information system or as a standalone application. It describes basic techniques and frameworks of transportation problems as well as important functional requirements, considering recent trends in the field of distribution planning. As a result, functional specification of basic features and other components of system are provided. The paper is a result of a joint initiative of the authors and a vendor of business information systems.

Early evolution of an X-ray emitting solar active region

International Nuclear Information System (INIS)

Wolfson, C.J.; Acton, L.W.; Leibacher, J.W.; Roethig, D.T.

1977-01-01

The birth and early evolution of a solar active region has been investigated using X-ray observations from the Lockheed Mapping X-Ray Heliometer on board the OSO-8 spacecraft. X-ray emission is observed within three hours of the first detection of Hα plage. At that time, a plasma temperature of 4 x 10 6 K in a region having a density of the order of 10 10 cm -3 is inferred. During the fifty hours following birth almost continuous flares or flare-like X-ray bursts are superimposed on a monotonically increasing base level of X-ray emission produced by plasma with a temperature of the order 3 x 10 6 K. If it is assumed that the X-rays result from heating due to dissipation of current systems or magnetic field reconnection, it can be concluded that flare-like X-ray emission soon after active region birth implies that the magnetic field probably emerges in a stressed or complex configuration. (Auth.)

Lower Bound of Energy-Latency Tradeoff of Opportunistic Routing in Multihop Networks

Directory of Open Access Journals (Sweden)

Gorce Jean-Marie

2011-01-01

Full Text Available Opportunistic networking aims at exploiting sporadic radio links to improve the connectivity of multihop networks and to foster data transmissions. The broadcast nature of wireless channels is an important feature that can be exploited to improve transmissions by using several potential receivers. Opportunistic relaying is thus the first brick for opportunistic networking. However, the advantage of opportunistic relaying may be degraded due to energy increase related to having multiple active receivers. This paper proposes a thorough analysis of opportunistic relaying efficiency under different realistic radio channel conditions. The study is intended to find the best tradeoff between two objectives: energy and latency minimizations, with a hard reliability constraint. We derive an optimal bound, namely, the Pareto front of the related optimization problem, which offers a good insight into the benefits of opportunistic routings compared with classical multihop routing schemes. Meanwhile, the lower bound provides a framework to optimize the parameters at the physical layer, MAC layer, and routing layer from the viewpoint of cross layer during the design or planning phase of a network.

Adaptive Bio-Inspired Wireless Network Routing for Planetary Surface Exploration

Science.gov (United States)

Alena, Richard I.; Lee, Charles

2004-01-01

Wireless mobile networks suffer connectivity loss when used in a terrain that has hills, and valleys when line of sight is interrupted or range is exceeded. To resolve this problem and achieve acceptable network performance, we have designed an adaptive, configurable, hybrid system to automatically route network packets along the best path between multiple geographically dispersed modules. This is very useful in planetary surface exploration, especially for ad-hoc mobile networks, where computational devices take an active part in creating a network infrastructure, and can actually be used to route data dynamically and even store data for later transmission between networks. Using inspiration from biological systems, this research proposes to use ant trail algorithms with multi-layered information maps (topographic maps, RF coverage maps) to determine the best route through ad-hoc network at real time. The determination of best route is a complex one, and requires research into the appropriate metrics, best method to identify the best path, optimizing traffic capacity, network performance, reliability, processing capabilities and cost. Real ants are capable of finding the shortest path from their nest to a food source without visual sensing through the use of pheromones. They are also able to adapt to changes in the environment using subtle clues. To use ant trail algorithms, we need to define the probability function. The artificial ant is, in this case, a software agent that moves from node to node on a network graph. The function to calculate the fitness (evaluate the better path) includes: length of the network edge, the coverage index, topology graph index, and pheromone trail left behind by other ant agents. Each agent modifies the environment in two different ways: 1) Local trail updating: As the ant moves between nodes it updates the amount of pheromone on the edge; and 2) Global trail updating: When all ants have completed a tour the ant that found the

Vestigialization of an Allosteric Switch: Genetic and Structural Mechanisms for the Evolution of Constitutive Activity in a Steroid Hormone Receptor

Science.gov (United States)

Bridgham, Jamie T.; Keay, June; Ortlund, Eric A.; Thornton, Joseph W.

2014-01-01

An important goal in molecular evolution is to understand the genetic and physical mechanisms by which protein functions evolve and, in turn, to characterize how a protein's physical architecture influences its evolution. Here we dissect the mechanisms for an evolutionary shift in function in the mollusk ortholog of the steroid hormone receptors (SRs), a family of biologically essential transcription factors. In vertebrates, the activity of SRs allosterically depends on binding a hormonal ligand; in mollusks, however, the SR ortholog (called ER, because of high sequence similarity to vertebrate estrogen receptors) activates transcription in the absence of ligand and does not respond to steroid hormones. To understand how this shift in regulation evolved, we combined evolutionary, structural, and functional analyses. We first determined the X-ray crystal structure of the ER of the Pacific oyster Crassostrea gigas (CgER), and found that its ligand pocket is filled with bulky residues that prevent ligand occupancy. To understand the genetic basis for the evolution of mollusk ERs' unique functions, we resurrected an ancient SR progenitor and characterized the effect of historical amino acid replacements on its functions. We found that reintroducing just two ancient replacements from the lineage leading to mollusk ERs recapitulates the evolution of full constitutive activity and the loss of ligand activation. These substitutions stabilize interactions among key helices, causing the allosteric switch to become “stuck” in the active conformation and making activation independent of ligand binding. Subsequent changes filled the ligand pocket without further affecting activity; by degrading the allosteric switch, these substitutions vestigialized elements of the protein's architecture required for ligand regulation and made reversal to the ancestral function more complex. These findings show how the physical architecture of allostery enabled a few large-effect mutations

Vestigialization of an allosteric switch: genetic and structural mechanisms for the evolution of constitutive activity in a steroid hormone receptor.

Directory of Open Access Journals (Sweden)

Jamie T Bridgham

2014-01-01

Full Text Available An important goal in molecular evolution is to understand the genetic and physical mechanisms by which protein functions evolve and, in turn, to characterize how a protein's physical architecture influences its evolution. Here we dissect the mechanisms for an evolutionary shift in function in the mollusk ortholog of the steroid hormone receptors (SRs, a family of biologically essential transcription factors. In vertebrates, the activity of SRs allosterically depends on binding a hormonal ligand; in mollusks, however, the SR ortholog (called ER, because of high sequence similarity to vertebrate estrogen receptors activates transcription in the absence of ligand and does not respond to steroid hormones. To understand how this shift in regulation evolved, we combined evolutionary, structural, and functional analyses. We first determined the X-ray crystal structure of the ER of the Pacific oyster Crassostrea gigas (CgER, and found that its ligand pocket is filled with bulky residues that prevent ligand occupancy. To understand the genetic basis for the evolution of mollusk ERs' unique functions, we resurrected an ancient SR progenitor and characterized the effect of historical amino acid replacements on its functions. We found that reintroducing just two ancient replacements from the lineage leading to mollusk ERs recapitulates the evolution of full constitutive activity and the loss of ligand activation. These substitutions stabilize interactions among key helices, causing the allosteric switch to become "stuck" in the active conformation and making activation independent of ligand binding. Subsequent changes filled the ligand pocket without further affecting activity; by degrading the allosteric switch, these substitutions vestigialized elements of the protein's architecture required for ligand regulation and made reversal to the ancestral function more complex. These findings show how the physical architecture of allostery enabled a few large

Hydrogen evolution activity and electrochemical stability of selected transition metal carbides in concentrated phosphoric acid

DEFF Research Database (Denmark)

Tomás García, Antonio Luis; Jensen, Jens Oluf; Bjerrum, Niels J.

2014-01-01

phosphoric acid were investigated in a temperature range from 80 to 170°C. A significant dependence of the activities on temperature was observed for all five carbide samples. Through the entire temperature range Group 6 metal carbides showed higher activity than that of the Group 5 metal carbides......Alternative catalysts based on carbides of Group 5 (niobium and tantalum) and 6 (chromium, molybdenum and tungsten) metals were prepared as films on the metallic substrates. The electrochemical activities of these carbide electrodes towards the hydrogen evolution reaction (HER) in concentrated...

Introducing radiality constraints in capacitated location-routing problems

Directory of Open Access Journals (Sweden)

Eliana Mirledy Toro Ocampo

2017-03-01

Full Text Available In this paper, we introduce a unified mathematical formulation for the Capacitated Vehicle Routing Problem (CVRP and for the Capacitated Location Routing Problem (CLRP, adopting radiality constraints in order to guarantee valid routes and eliminate subtours. This idea is inspired by formulations already employed in electric power distribution networks, which requires a radial topology in its operation. The results show that the proposed formulation greatly improves the convergence of the solver.

Operations Research for Freight Train Routing and Scheduling

DEFF Research Database (Denmark)

Harrod, Steven; Gorman, Michael F.

2011-01-01

This article describes the service design activities that plan and implement the rail freight operating plan. Elements of strategic service design include the setting of train frequency, the routing of cars among trains, and the consolidation of cars, called blocking. At the operational level......, trains are dispatched either according to train paths configured in advance, called timetables, or according to priority rules. We describe the North American and European practice along with selected modeling and problem solving methodologies appropriate for each of the operating conditions described...

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.

Delay Management with Re-Routing of Passengers

NARCIS (Netherlands)

T.A.B. Dollevoet (Twan); D. Huisman (Dennis); M.E. Schmidt (Marie); A. Schöbel (Anita)

2010-01-01

textabstractThe question of delay management is whether trains should wait for a delayed feeder train or should depart on time. In classical delay management models passengers always take their originally planned route. In this paper, we propose a model where re-routing of passengers is

Joint route planning under varying market conditions

NARCIS (Netherlands)

Cruijssen, Frans; Bräysy, Olli; Dullaert, Wout; Fleuren, Hein; Salomon, Marc

2007-01-01

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

Many routes leading to Rome: Potential causes for the multi-route migration system of Red Knots Calidris canutus islandica

NARCIS (Netherlands)

Bauer, S.; Ens, B.J.; Klaassen, M.R.J.

2010-01-01

Migrants, such as birds or representatives of other taxa, usually make use of several stopover sites to cover the distance between their site of origin and destination. Potentially, multiple routes exist, but often little is known about the causes and consequences of alternative migration routes.

A novel insight into beaconless geo-routing

KAUST Repository

Bader, Ahmed

2012-12-01

Beaconless geo-routing protocols have been traditionally analyzed assuming equal communication ranges for the data and control packets. This is not true in reality, since the communication range is in practice function of the packet length. As a consequence, a substantial discrepancy may exist between analytical and empirical results offered in beaconless geo-routing literature. Furthermore, performance of beaconless geo-routing protocols has typically considered using single-hop metrics only. End-to-end performance is considered in literature only occasionally and mainly in terms of simulation only. In this paper, we re-examine this class of protocols. We first incorporate practical packet detection models in order to capture the dependency of the communication range on the packet\\'s length. We then develop a detailed analytical framework for the end-to-end delay and energy performance of beaconless geo-routing protocols. Finally, we present two different application scenarios and study various tradeoffs in light of the framework developed. © 2012 IEEE.

Location-Aided Reliable Routing for Opportunistic Networks

Institute of Scientific and Technical Information of China (English)

Yong Yang; Zhi Ren; Jibi Li

2012-01-01

In our study, we investigate the problem of location-based routing in opportunistic networks. Due to the uncertainty of end-to-end paths between sources and destinations, the classical location-based ad hoc routing protocols cannot adapt to the environment of opportunistic networks, which leads to the decrease of the delivery rate of data. To address it, we propose in this paper a novel location-aided routing protocol which is suitable for opportunistic networks. In our protocol, a node can send location information on demand by using prediction mechanism, and when sending a data packet, the node chooses multiple neighbors which are closer to the destination as next hops. If the candidate neighbors do not exist, the node carries the data till it meets a proper neighbor or the destination. Theoretical analysis and simulation results show that our proposed protocol outperforms DREAM (Distance Routing Effect Protocol Mobility) and one of its improved versions, BFDREAM (Boundary Forwarding DREAM), in terms of the delivery rate and overhead.

Coordinated Platoon Routing in a Metropolitan Network

Energy Technology Data Exchange (ETDEWEB)

Larson, Jeffrey; Munson, Todd; Sokolov, Vadim

2016-10-10

Platooning vehicles—connected and automated vehicles traveling with small intervehicle distances—use less fuel because of reduced aerodynamic drag. Given a network de- fined by vertex and edge sets and a set of vehicles with origin/destination nodes/times, we model and solve the combinatorial optimization problem of coordinated routing of vehicles in a manner that routes them to their destination on time while using the least amount of fuel. Common approaches decompose the platoon coordination and vehicle routing into separate problems. Our model addresses both problems simultaneously to obtain the best solution. We use modern modeling techniques and constraints implied from analyzing the platoon routing problem to address larger numbers of vehicles and larger networks than previously considered. While the numerical method used is unable to certify optimality for candidate solutions to all networks and parameters considered, we obtain excellent solutions in approximately one minute for much larger networks and vehicle sets than previously considered in the literature.

THE EVOLUTION OF ACTIVE GALACTIC NUCLEI IN CLUSTERS OF GALAXIES TO REDSHIFT 1.3

International Nuclear Information System (INIS)

Martini, Paul; Sivakoff, Gregory R.; Mulchaey, John S.

2009-01-01

We have measured the luminous active galactic nucleus (AGN) population in a large sample of clusters of galaxies and find evidence for a substantial increase in the cluster AGN population from z ∼ 0.05 to z ∼ 1.3. The present sample now includes 32 clusters of galaxies, including 15 clusters above z = 0.4, which corresponds to a three-fold increase compared to our previous work at high redshift. At z R R (z) + 1 that host AGNs with rest-frame, hard X-ray [2-10 keV] luminosities L X,H ≥ 10 43 erg s -1 . The AGN fraction increases from f A = 0.134 +0.18 -0.087 % at a median z = 0.19 to f A = 1.00 +0.29 -0.23 % at a median z = 0.72. Our best estimate of the evolution is a factor of 8 increase to z = 1 and the statistical significance of the increase is 3.8σ. This dramatic evolution is qualitatively similar to the evolution of the star-forming galaxy population in clusters known as the Butcher-Oemler effect. We discuss the implications of this result for the coevolution of black holes and galaxies in clusters, the evolution of AGN feedback, searches for clusters with the Sunyaev-Zel'dovich effect, and the possible detection of environment-dependent downsizing.

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...

Cognitive load during route selection increases reliance on spatial heuristics.

Science.gov (United States)

Brunyé, Tad T; Martis, Shaina B; Taylor, Holly A

2018-05-01

Planning routes from maps involves perceiving the symbolic environment, identifying alternate routes and applying explicit strategies and implicit heuristics to select an option. Two implicit heuristics have received considerable attention, the southern route preference and initial segment strategy. This study tested a prediction from decision-making theory that increasing cognitive load during route planning will increase reliance on these heuristics. In two experiments, participants planned routes while under conditions of minimal (0-back) or high (2-back) working memory load. In Experiment 1, we examined how memory load impacts the southern route heuristic. In Experiment 2, we examined how memory load impacts the initial segment heuristic. Results replicated earlier results demonstrating a southern route preference (Experiment 1) and initial segment strategy (Experiment 2) and further demonstrated that evidence for heuristic reliance is more likely under conditions of concurrent working memory load. Furthermore, the extent to which participants maintained efficient route selection latencies in the 2-back condition predicted the magnitude of this effect. Together, results demonstrate that working memory load increases the application of heuristics during spatial decision making, particularly when participants attempt to maintain quick decisions while managing concurrent task demands.

Expand classical drug administration ways by emerging routes using dendrimer drug delivery systems: a concise overview.

Science.gov (United States)

Mignani, Serge; El Kazzouli, Saïd; Bousmina, Mosto; Majoral, Jean-Pierre

2013-10-01

Drugs are introduced into the body by numerous routes such as enteral (oral, sublingual and rectum administration), parenteral (intravascular, intramuscular, subcutaneous and inhalation administration), or topical (skin and mucosal membranes). Each route has specific purposes, advantages and disadvantages. Today, the oral route remains the preferred one for different reasons such as ease and compliance by patients. Several nanoformulated drugs have been already approved by the FDA, such as Abelcet®, Doxil®, Abraxane® or Vivagel®(Starpharma) which is an anionic G4-poly(L-lysine)-type dendrimer showing potent topical vaginal microbicide activity. Numerous biochemical studies, as well as biological and pharmacological applications of both dendrimer based products (dendrimers as therapeutic compounds per se, like Vivagel®) and dendrimers as drug carriers (covalent conjugation or noncovalent encapsulation of drugs) were described. It is widely known that due to their outstanding physical and chemical properties, dendrimers afforded improvement of corresponding carried-drugs as dendrimer-drug complexes or conjugates (versus plain drug) such as biodistribution and pharmacokinetic behaviors. The purpose of this manuscript is to review the recent progresses of dendrimers as nanoscale drug delivery systems for the delivery of drugs using enteral, parenteral and topical routes. In particular, we focus our attention on the emerging and promising routes such as oral, transdermal, ocular and transmucosal routes using dendrimers as delivery systems. Copyright © 2013 Elsevier B.V. All rights reserved.

A Joint Link and Channel Assignment Routing Scheme for Cognitive Radio Networks

Directory of Open Access Journals (Sweden)

H.S.Zhao

2013-12-01

Full Text Available Cognitive radio (CR is a promising technology that enables opportunistic utilization of the temporarily vacant spectrum to mitigate the spectrum scarcity in wireless communications. Since secondary users (SUs should vacate the channel in use immediately after detecting the reappearances of primary users (PUs in cognitive radio networks (CRNs, the route reliability is a distinctive challenge for routing in CRNs. Furthermore, the throughput requirement of an SU session should be satisfied and it is always preferable to select a route with less negative influence on other current or latish sessions. To account for the route reliability challenge, we study the joint link and channel assignment routing problem for CRNs. It is formulated in a form of integer nonlinear programming (INLP, which is NP-hard, with the objective of minimizing the interference of a new route to other routes while providing route reliability and throughput guarantee. An on-demand route discovery algorithm is proposed to find reliable candidate paths, while a joint link and channel assignment routing algorithm with sequentially-connected-link coordination is proposed to choose the near-optimal route for improving the route reliability and minimizing negative influence. Simulation results demonstrate that the proposed algorithm achieves considerable improvement over existing schemes in both route reliability and throughput.

Selective epidemic vaccination under the performant routing algorithms

Science.gov (United States)

Bamaarouf, O.; Alweimine, A. Ould Baba; Rachadi, A.; EZ-Zahraouy, H.

2018-04-01

Despite the extensive research on traffic dynamics and epidemic spreading, the effect of the routing algorithms strategies on the traffic-driven epidemic spreading has not received an adequate attention. It is well known that more performant routing algorithm strategies are used to overcome the congestion problem. However, our main result shows unexpectedly that these algorithms favor the virus spreading more than the case where the shortest path based algorithm is used. In this work, we studied the virus spreading in a complex network using the efficient path and the global dynamic routing algorithms as compared to shortest path strategy. Some previous studies have tried to modify the routing rules to limit the virus spreading, but at the expense of reducing the traffic transport efficiency. This work proposed a solution to overcome this drawback by using a selective vaccination procedure instead of a random vaccination used often in the literature. We found that the selective vaccination succeeded in eradicating the virus better than a pure random intervention for the performant routing algorithm strategies.

Modeling Stochastic Route Choice Behaviors with Equivalent Impedance

Directory of Open Access Journals (Sweden)

Jun Li

2015-01-01

Full Text Available A Logit-based route choice model is proposed to address the overlapping and scaling problems in the traditional multinomial Logit model. The nonoverlapping links are defined as a subnetwork, and its equivalent impedance is explicitly calculated in order to simply network analyzing. The overlapping links are repeatedly merged into subnetworks with Logit-based equivalent travel costs. The choice set at each intersection comprises only the virtual equivalent route without overlapping. In order to capture heterogeneity in perception errors of different sizes of networks, different scale parameters are assigned to subnetworks and they are linked to the topological relationships to avoid estimation burden. The proposed model provides an alternative method to model the stochastic route choice behaviors without the overlapping and scaling problems, and it still maintains the simple and closed-form expression from the MNL model. A link-based loading algorithm based on Dial’s algorithm is proposed to obviate route enumeration and it is suitable to be applied on large-scale networks. Finally a comparison between the proposed model and other route choice models is given by numerical examples.

Analysis of Pervasive Mobile Ad Hoc Routing Protocols

Science.gov (United States)

Qadri, Nadia N.; Liotta, Antonio

Mobile ad hoc networks (MANETs) are a fundamental element of pervasive networks and therefore, of pervasive systems that truly support pervasive computing, where user can communicate anywhere, anytime and on-the-fly. In fact, future advances in pervasive computing rely on advancements in mobile communication, which includes both infrastructure-based wireless networks and non-infrastructure-based MANETs. MANETs introduce a new communication paradigm, which does not require a fixed infrastructure - they rely on wireless terminals for routing and transport services. Due to highly dynamic topology, absence of established infrastructure for centralized administration, bandwidth constrained wireless links, and limited resources in MANETs, it is challenging to design an efficient and reliable routing protocol. This chapter reviews the key studies carried out so far on the performance of mobile ad hoc routing protocols. We discuss performance issues and metrics required for the evaluation of ad hoc routing protocols. This leads to a survey of existing work, which captures the performance of ad hoc routing algorithms and their behaviour from different perspectives and highlights avenues for future research.

Trade routes and plague transmission in pre-industrial Europe.

Science.gov (United States)

Yue, Ricci P H; Lee, Harry F; Wu, Connor Y H

2017-10-11

Numerous historical works have mentioned that trade routes were to blame for the spread of plague in European history, yet this relationship has never been tested by quantitative evidence. Here, we resolve the hypothetical role of trade routes through statistical analysis on the geo-referenced major trade routes in the early modern period and the 6,656 geo-referenced plague outbreak records in AD1347-1760. Ordinary Least Square (OLS) estimation results show that major trade routes played a dominant role in spreading plague in pre-industrial Europe. Furthermore, the negative correlation between plague outbreaks and their distance from major trade ports indicates the absence of a permanent plague focus in the inland areas of Europe. Major trade routes decided the major plague outbreak hotspots, while navigable rivers determined the geographic pattern of sporadic plague cases. A case study in Germany indicates that plague penetrated further into Europe through the local trade route network. Based on our findings, we propose the mechanism of plague transmission in historical Europe, which is imperative in demonstrating how pandemics were spread in recent human history.

Preventing Restricted Space Inference in Online Route Planning Services

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Florian Dorfmeister

2016-03-01

Full Text Available Online route planning services compute routes from any given location to a desired destination address. Unlike offline implementations, they do so in a traffic-aware fashion by taking into consideration up-to-date map data and real-time traffic information. In return, users have to provide precise location information about a route’s endpoints to a not necessarily trusted service provider. As suchlike leakage of personal information threatens a user’s privacy and anonymity, this paper presents PrOSPR, a comprehensive approach for using current online route planning services in a privacy-preserving way, and introduces the concept of k-immune route requests to avert inference attacks based on restricted space information. Using a map-based approach for creating cloaked regions for the start and destination addresses, our solution queries the online service for routes between subsets of points from these regions. This, however, might result in the returned path deviating from the optimal route. By means of empirical evaluation on a real road network, we demonstrate the feasibility of our approach regarding quality of service and communication overhead.

An integrated approach to route selection in slurry pipeline design

Energy Technology Data Exchange (ETDEWEB)

Betinol, Roy G.; Altmann, Nara [Brass Chile S.A., Santiago (Chile)

2009-12-19

The pressure to get engineering projects done and constructed as fast as possible in order to take advantage of the high prices in metals and petrochemicals has been driving companies to skip the conceptual phase and go straight into basic engineering with cost estimates in the level of 15% accuracy. By-passing early engineering and demanding higher cost estimating accuracy is a contradiction. In most cases, savings made on capital investment is much higher had money been spent in conceptual studies which allow for the optimal solution to be found. This paper reviews one of the key aspects in conceptual engineering of slurry pipeline designs: route selection. This activity is often overlooked, causing capital cost and operating difficulties to rise unnecessarily. This paper describes and gives example on how an integrated client/engineering company's approach to route selection can produce significant savings in pipeline construction and operating costs. (author)

Time and timing in vehicle routing problems

NARCIS (Netherlands)

Jabali, O.

2010-01-01

The distribution of goods to a set of geographically dispersed customers is a common problem faced by carrier companies, well-known as the Vehicle Routing Problem (VRP). The VRP consists of finding an optimal set of routes that minimizes total travel times for a given number of vehicles with a fixed

Principles of Vessel Route Planning in Ice on the Northern Sea Route

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Tadeusz Pastusiak

2016-12-01

Full Text Available A complex of ice cover characteristics and the season of the year were considered in relation to vessel route planning in ice-covered areas on the NSR. The criteria for navigation in ice - both year-round and seasonal were analyzed. The analysis of the experts knowledge, dissipated in the literature, allowed to identify some rules of route planning in ice-covered areas. The most important processes from the navigation point of view are the development and disintegration of ice, the formation and disintegration of fast ice and behavior of the ice massifs and polynyas. The optimal route is selected on basis of available analysis and forecast maps of ice conditions and ice class, draught and seaworthiness of the vessel. The boundary of the ice indicates areas accessible to vessels without ice class. Areas with a concentration of ice from 0 to 6/10 are used for navigation of vessels of different ice classes. Areas of concentration of ice from 7/10 up are eligible for navigation for icebreakers and vessels with a high ice class with the assistance of icebreakers. These rules were collected in the decision tree. Following such developed decision-making model the master of the vessel may take decision independently by accepting grading criteria of priorities resulting from his knowledge, experience and the circumstances of navigation. Formalized form of decision making model reduces risk of the "human factor" in the decision and thereby help improve the safety of maritime transport.

MoS2 nanosheets direct supported on reduced graphene oxide: An advanced electrocatalyst for hydrogen evolution reaction.

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Jiamu Cao

Full Text Available Molybdenum disulfide nanosheets/reduced graphene oxide (MoS2 NSs/rGO nanohybrid as a highly effective catalyst for hydrogen evolution reaction (HER have been successfully synthesized by a facile microwave-assisted method. The results clearly reveal that direct grown of MoS2 NSs on rGO have been achieved. Electrochemical tests show that the as-prepared hybrid material exhibited excellent HER activity, with a small Tafel slope of 57 mV dec-1, an overpotential of 130 mV and remarkable cycling stability. After analysis, the observed outstanding catalytic performance can be attributed to the uniform distribution of the MoS2 NSs, which are characterized by the presence of multiple active sites as well as the effective electron transport route provided by the conductive rGO substrate. Moreover, according to the classic theory, the mechanism governing of the catalytic HER on the MoS2 NSs/rGO nanohybrid has been clarified.

Throughput Capacity of Ad Hoc Networks with Route Discovery

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Blum Rick S

2007-01-01

Full Text Available Throughput capacity of large ad hoc networks has been shown to scale adversely with the size of network . However the need for the nodes to find or repair routes has not been analyzed in this context. In this paper, we explicitly take route discovery into account and obtain the scaling law for the throughput capacity under general assumptions on the network environment, node behavior, and the quality of route discovery algorithms. We also discuss a number of possible scenarios and show that the need for route discovery may change the scaling for the throughput capacity.

What is the optimal architecture for visual information routing?

Science.gov (United States)

Wolfrum, Philipp; von der Malsburg, Christoph

2007-12-01

Analyzing the design of networks for visual information routing is an underconstrained problem due to insufficient anatomical and physiological data. We propose here optimality criteria for the design of routing networks. For a very general architecture, we derive the number of routing layers and the fanout that minimize the required neural circuitry. The optimal fanout l is independent of network size, while the number k of layers scales logarithmically (with a prefactor below 1), with the number n of visual resolution units to be routed independently. The results are found to agree with data of the primate visual system.

Self-Interested Routing in Queueing Networks

OpenAIRE

Ali K. Parlaktürk; Sunil Kumar

2004-01-01

We study self-interested routing in stochastic networks, taking into account the discrete stochastic dynamics of such networks. We analyze a two-station multiclass queueing network in which the system manager chooses the scheduling rule and individual customers choose routes in a self-interested manner. We show that this network can be unstable in Nash equilibrium under some scheduling rules. We also design a nontrivial scheduling rule that negates the performance degradation resulting from s...

Identifying and prioritizing ungulate migration routes for landscape-level conservation

Science.gov (United States)

Sawyer, Hall; Kauffman, Matthew J.; Nielson, Ryan M.; Horne, Jon S.

2009-01-01

As habitat loss and fragmentation increase across ungulate ranges, identifying and prioritizing migration routes for conservation has taken on new urgency. Here we present a general framework using the Brownian bridge movement model (BBMM) that: (1) provides a probabilistic estimate of the migration routes of a sampled population, (2) distinguishes between route segments that function as stopover sites vs. those used primarily as movement corridors, and (3) prioritizes routes for conservation based upon the proportion of the sampled population that uses them. We applied this approach to a migratory mule deer (Odocoileus hemionus) population in a pristine area of southwest Wyoming, USA, where 2000 gas wells and 1609 km of pipelines and roads have been proposed for development. Our analysis clearly delineated where migration routes occurred relative to proposed development and provided guidance for on-the-ground conservation efforts. Mule deer migration routes were characterized by a series of stopover sites where deer spent most of their time, connected by movement corridors through which deer moved quickly. Our findings suggest management strategies that differentiate between stopover sites and movement corridors may be warranted. Because some migration routes were used by more mule deer than others, proportional level of use may provide a reasonable metric by which routes can be prioritized for conservation. The methods we outline should be applicable to a wide range of species that inhabit regions where migration routes are threatened or poorly understood.

Comparison of Mucosal, Subcutaneous and Intraperitoneal Routes of Rat Leptospira Infection

Science.gov (United States)

Zilber, Anne-Laure; Belli, Patrick; Grezel, Delphine; Artois, Marc; Kodjo, Angeli; Djelouadji, Zoheira

2016-01-01

Leptospirosis is a zoonosis found worldwide that is caused by a spirochete. The main reservoirs of Leptospira, which presents an asymptomatic infection, are wild rodents, including the brown rat (Rattus norvegicus). Experimental studies of the mechanisms of its renal colonization in rats have previously used an intraperitoneal inoculation route. However, knowledge of rat-rat transmission requires the use of a natural route of inoculation, such as a mucosal or subcutaneous route. We investigated for the first time the effects of subcutaneous and mucosal inoculation routes compared to the reference intraperitoneal route during Leptospira infection in adult rats. Infection characteristics were studied using Leptospira renal isolation, serology, and molecular and histological analyses. Leptospira infection was asymptomatic using each inoculation route, and caused similar antibody production regardless of renal colonization. The observed renal colonization rates were 8 out of 8 rats, 5 out of 8 rats and 1 out of 8 rats for the intraperitoneal, mucosal and subcutaneous inoculation routes, respectively. Thus, among the natural infection routes studied, mucosal inoculation was more efficient for renal colonization associated with urinary excretion than the subcutaneous route and induced a slower-progressing infection than the intraperitoneal route. These results can facilitate understanding of the infection modalities in rats, unlike the epidemiological studies conducted in wild rats. Future studies of other natural inoculation routes in rat models will increase our knowledge of rat-rat disease transmission and allow the investigation of infection kinetics. PMID:27031867

Energy Aware Cluster Based Routing Scheme For Wireless Sensor Network

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Roy Sohini

2015-09-01

Full Text Available Wireless Sensor Network (WSN has emerged as an important supplement to the modern wireless communication systems due to its wide range of applications. The recent researches are facing the various challenges of the sensor network more gracefully. However, energy efficiency has still remained a matter of concern for the researches. Meeting the countless security needs, timely data delivery and taking a quick action, efficient route selection and multi-path routing etc. can only be achieved at the cost of energy. Hierarchical routing is more useful in this regard. The proposed algorithm Energy Aware Cluster Based Routing Scheme (EACBRS aims at conserving energy with the help of hierarchical routing by calculating the optimum number of cluster heads for the network, selecting energy-efficient route to the sink and by offering congestion control. Simulation results prove that EACBRS performs better than existing hierarchical routing algorithms like Distributed Energy-Efficient Clustering (DEEC algorithm for heterogeneous wireless sensor networks and Energy Efficient Heterogeneous Clustered scheme for Wireless Sensor Network (EEHC.

DRO: domain-based route optimization scheme for nested mobile networks

Directory of Open Access Journals (Sweden)

Chuang Ming-Chin

2011-01-01

Full Text Available Abstract The network mobility (NEMO basic support protocol is designed to support NEMO management, and to ensure communication continuity between nodes in mobile networks. However, in nested mobile networks, NEMO suffers from the pinball routing problem, which results in long packet transmission delays. To solve the problem, we propose a domain-based route optimization (DRO scheme that incorporates a domain-based network architecture and ad hoc routing protocols for route optimization. DRO also improves the intra-domain handoff performance, reduces the convergence time during route optimization, and avoids the out-of-sequence packet problem. A detailed performance analysis and simulations were conducted to evaluate the scheme. The results demonstrate that DRO outperforms existing mechanisms in terms of packet transmission delay (i.e., better route-optimization, intra-domain handoff latency, convergence time, and packet tunneling overhead.

Efficient Secure and Privacy-Preserving Route Reporting Scheme for VANETs

Science.gov (United States)

Zhang, Yuanfei; Pei, Qianwen; Dai, Feifei; Zhang, Lei

2017-10-01

Vehicular ad-hoc network (VANET) is a core component of intelligent traffic management system which could provide various of applications such as accident prediction, route reporting, etc. Due to the problems caused by traffic congestion, route reporting becomes a prospective application which can help a driver to get optimal route to save her travel time. Before enjoying the convenience of route reporting, security and privacy-preserving issues need to be concerned. In this paper, we propose a new secure and privacy-preserving route reporting scheme for VANETs. In our scheme, only an authenticated vehicle can use the route reporting service provided by the traffic management center. Further, a vehicle may receive the response from the traffic management center with low latency and without violating the privacy of the vehicle. Experiment results show that our scheme is much more efficiency than the existing one.

Planning Routes Across Economic Terrains: Maximizing Utility, Following Heuristics

Science.gov (United States)

Zhang, Hang; Maddula, Soumya V.; Maloney, Laurence T.

2010-01-01

We designed an economic task to investigate human planning of routes in landscapes where travel in different kinds of terrain incurs different costs. Participants moved their finger across a touch screen from a starting point to a destination. The screen was divided into distinct kinds of terrain and travel within each kind of terrain imposed a cost proportional to distance traveled. We varied costs and spatial configurations of terrains and participants received fixed bonuses minus the total cost of the routes they chose. We first compared performance to a model maximizing gain. All but one of 12 participants failed to adopt least-cost routes and their failure to do so reduced their winnings by about 30% (median value). We tested in detail whether participants’ choices of routes satisfied three necessary conditions (heuristics) for a route to maximize gain. We report failures of one heuristic for 7 out of 12 participants. Last of all, we modeled human performance with the assumption that participants assign subjective utilities to costs and maximize utility. For 7 out 12 participants, the fitted utility function was an accelerating power function of actual cost and for the remaining 5, a decelerating power function. We discuss connections between utility aggregation in route planning and decision under risk. Our task could be adapted to investigate human strategy and optimality of route planning in full-scale landscapes. PMID:21833269

PLANNING ROUTES ACROSS ECONOMIC TERRAINS: MAXIMIZING UTILITY, FOLLOWING HEURISTICS

Directory of Open Access Journals (Sweden)

Hang eZhang

2010-12-01

Full Text Available We designed an economic task to investigate human planning of routes in landscapes where travel in different kinds of terrain incurs different costs. Participants moved their finger across a touch screen from a starting point to a destination. The screen was divided into distinct kinds of terrain and travel within each kind of terrain imposed a cost proportional to distance traveled. We varied costs and spatial configurations of terrains and participants received fixed bonuses minus the total cost of the routes they chose. We first compared performance to a model maximizing gain. All but one of 12 participants failed to adopt least-cost routes and their failure to do so reduced their winnings by about 30% (median value. We tested in detail whether participants’ choices of routes satisfied three necessary conditions (heuristics for a route to maximize gain. We report failures of one heuristic for 7 out of 12 participants. Last of all, we modeled human performance with the assumption that participants assign subjective utilities to costs and maximize utility. For 7 out 12 participants, the fitted utility function was an accelerating power function of actual cost and for the remaining 5, a decelerating power function. We discuss connections between utility aggregation in route planning and decision under risk. Our task could be adapted to investigate human strategy and optimality of route planning in full-scale landscapes.

Evolution of management activities and performance of the Point Lepreau Steam Generators

International Nuclear Information System (INIS)

Slade, J.; Keating, J.; Gendron, T.

2007-01-01

The Point Lepreau steam generators have been in service since 1983 when the plant was commissioned. During the first thirteen years of operation, Point Lepreau steam generator maintenance issues led to 3-4% unplanned plant incapability Steam generator fouling, corrosion, and the introduction of foreign materials during maintenance led to six tube leaks, two unplanned outages, two lengthy extended outages, and degraded thermal performance during this period. In recognition of the link between steam generator maintenance activities and plant performance, improvements to steam generator management activities have been continuously implemented since 1987. This paper reviews the evolution of steam generator management activities at Point Lepreau and the resulting improved trends in performance. Plant incapability from unplanned steam generator maintenance has been close to zero since 1996. The positive trends have provided a strong basis for the management strategies developed for post-refurbishment operation. (author)

29 CFR 1910.36 - Design and construction requirements for exit routes.

Science.gov (United States)

2010-07-01

... construction requirements for exit routes. (a) Basic requirements. Exit routes must meet the following design... your workplace, consult NFPA 101-2000, Life Safety Code. (c) Exit discharge. (1) Each exit discharge... route must be adequate. (1) Exit routes must support the maximum permitted occupant load for each floor...

Research on the optimization of vehicle distribution routes in logistics enterprises

Science.gov (United States)

Fan, Zhigou; Ma, Mengkun

2018-01-01

With the rapid development of modern logistics, the vehicle routing problem has become one of the urgent problems in the logistics industry. The rationality of distribution route planning directly affects the efficiency and quality of logistics distribution. This paper first introduces the definition of logistics distribution and the three methods of optimizing the distribution routes, and then analyzes the current vehicle distribution route by using a representative example, finally puts forward the optimization schemes of logistics distribution route.

Segmented Routing for Speed-Performance and Routability in Field-Programmable Gate Arrays

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Stephen Brown

1996-01-01

Full Text Available This paper addresses several issues involved for routing in Field-Programmable Gate Arrays (FPGAs that have both horizontal and vertical routing channels, with wire segments of various lengths. Routing is studied by using CAD routing tools to map a set of benchmark circuits into FPGAs, and measuring the effects that various parameters of the CAD tools have on the implementation of the circuits. A two-stage routing strategy of global followed by detailed routing is used, and the effects of both of these CAD stages are discussed, with emphasis on detailed routing. We present a new detailed routing algorithm designed specifically for the types of routing structures found in the most recent generation of FPGAs, and show that the new algorithm achieves significantly better results than previously published FPGA routers with respect to the speed-performance of implemented circuits.

Porcelain tiles by the dry route

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Boschi, A. O.

2010-10-01

Full Text Available In Brazil, the second largest tile producer of the world, at present, 70% of the tiles are produced by the dry route. One of the main reasons that lead to this development is the fact that the dry route uses approximately 30% less thermal energy them the traditional wet route. The increasing world concern with the environment and the recognition of the central role played by the water also has pointed towards privileging dry processes. In this context the objective of the present work is to study the feasibility of producing high quality porcelain tiles by the dry route. A brief comparison of the dry and wet route, in standard conditions industrially used today to produce tiles that are not porcelain tiles, shows that there are two major differences: the particle sizes obtained by the wet route are usually considerably finer and the capability of mixing the different minerals, the intimacy of the mixture, is also usually better in the wet route. The present work studied the relative importance of these differences and looked for raw materials and operational conditions that would result in better performance and glazed porcelain tiles of good quality.

En Brasil, en este momento segundo productor mundial, el 70% de los pavimentos cerámicos se obtiene por vía seca. Una de las razones fundamentales se debe a que esta vía supone un consumo energético inferior, en un 30%, a la via húmeda tradicional. La creciente preocupación mundial sobre los problemas medioambientales y el reconocimiento del papel central que juega el agua en este proceso han favorecido el desarrollo de la vía seca. En este contexto, el objetivo del presente trabajo es estudiar la viabilidad de la producción de pavimentos porcelánicos de alta calidad por vía seca. Una breve comparación entre ambas vías, en las condiciones standard de producción vigentes para producciones que no son de porcelánico, indican que existen dos diferencias substanciales; el tamaño de

Research on routing algorithm based on the VANET

Directory of Open Access Journals (Sweden)

AN Li

2016-01-01

Full Text Available For the characteristics of high speed mobility of nodes, frequent changes of dynamic topology and frequent interrupts of the communication links in the VANET, this paper analyzed the defect of the current mobile ad-hoc network routing protocol, and carried on the simulation analysis on the adaptability of AODV, DSR and DSDV routing protocols in VANET applications in the VANET. Through the above research, this paper obtained the conclusion that the AODV routing protocol is more suitable for vehicular ad hoc network environment

Route selection for the transport of hazardous materials

Energy Technology Data Exchange (ETDEWEB)

Seiler, F A

1988-12-01

The factors governing the risk-weighted selection of routes for transport of hazardous materials are analyzed. Starting from a formulation for the total risk of these transports that assumes complete information, approximations for the more realistic case of partial and uncertain information are discussed. These approximations involve well-known risk assessment techniques and mathematical methods; among the latter, Monte Carlo calculations hold the most promise. The actual route selection is based on an index of total societal cost, evaluated for a set of potential routes. (author)

ARBR: Adaptive reinforcement-based routing for DTN

KAUST Repository

Elwhishi, Ahmed

2010-10-01

This paper introduces a novel routing protocol in Delay Tolerant Networks (DTNs), aiming to solve the online distributed routing problem. By manipulating a collaborative reinforcement learning technique, a group of nodes can cooperate with each other and make a forwarding decision for the stored messages based on a cost function at each contact with another node. The proposed protocol is characterized by not only considering the contact time statistics under a novel contact model, but also looks into the feedback on user behavior and network conditions, such as congestion and buffer occupancy sampled during each previous contact with any other node. Therefore, the proposed protocol can achieve high efficiency via an adaptive and intelligent routing mechanism according to network conditions. Extensive simulation is conducted to verify the proposed protocol, where a comparison is made with a number of existing encounter-based routing protocols in term of the number of transmissions of each message, message delivery delay, and delivery ratio. The results of the simulation demonstrate the effectiveness of the proposed technique.

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

Route Fidelity during Marine Megafauna Migration

Directory of Open Access Journals (Sweden)

Travis W. Horton

2017-12-01

Full Text Available The conservation and protection of marine megafauna require robust knowledge of where and when animals are located. Yet, our ability to predict animal distributions in space and time remains limited due to difficulties associated with studying elusive animals with large home ranges. The widespread deployment of satellite telemetry technology creates unprecedented opportunities to remotely monitor animal movements and to analyse the spatial and temporal trajectories of these movements from a variety of geophysical perspectives. Reproducible patterns in movement trajectories can help elucidate the potential mechanisms by which marine megafauna navigate across vast expanses of open-ocean. Here, we present an empirical analysis of humpback whale (Megaptera novaeangliae, great white shark (Carcharodon carcharias, and northern elephant seal (Mirounga angustirostris satellite telemetry-derived route fidelity movements in magnetic and gravitational coordinates. Our analyses demonstrate that: (1 humpback whales, great white sharks and northern elephant seals are capable of performing route fidelity movements across millions of square kilometers of open ocean with a spatial accuracy of better than 150 km despite temporal separations as long as 7 years between individual movements; (2 route fidelity movements include significant (p < 0.05 periodicities that are comparable in duration to the lunar cycles and semi-cycles; (3 latitude and bedrock-dependent gravitational cues are stronger predictors of route fidelity movements than spherical magnetic coordinate cues when analyzed with respect to the temporally dependent moon illumination cycle. We further show that both route fidelity and non-route fidelity movement trajectories, for all three species, describe overlapping in-phase or antiphase sinusoids when individual movements are normalized to the gravitational acceleration present at migratory departure sites. Although these empirical results provide an

A Family of ACO Routing Protocols for Mobile Ad Hoc Networks

Science.gov (United States)

Rupérez Cañas, Delfín; Sandoval Orozco, Ana Lucila; García Villalba, Luis Javier; Kim, Tai-hoon

2017-01-01

In this work, an ACO routing protocol for mobile ad hoc networks based on AntHocNet is specified. As its predecessor, this new protocol, called AntOR, is hybrid in the sense that it contains elements from both reactive and proactive routing. Specifically, it combines a reactive route setup process with a proactive route maintenance and improvement process. Key aspects of the AntOR protocol are the disjoint-link and disjoint-node routes, separation between the regular pheromone and the virtual pheromone in the diffusion process and the exploration of routes, taking into consideration the number of hops in the best routes. In this work, a family of ACO routing protocols based on AntOR is also specified. These protocols are based on protocol successive refinements. In this work, we also present a parallelized version of AntOR that we call PAntOR. Using programming multiprocessor architectures based on the shared memory protocol, PAntOR allows running tasks in parallel using threads. This parallelization is applicable in the route setup phase, route local repair process and link failure notification. In addition, a variant of PAntOR that consists of having more than one interface, which we call PAntOR-MI (PAntOR-Multiple Interface), is specified. This approach parallelizes the sending of broadcast messages by interface through threads. PMID:28531159

A Family of ACO Routing Protocols for Mobile Ad Hoc Networks.

Science.gov (United States)

Rupérez Cañas, Delfín; Sandoval Orozco, Ana Lucila; García Villalba, Luis Javier; Kim, Tai-Hoon

2017-05-22

In this work, an ACO routing protocol for mobile ad hoc networks based on AntHocNet is specified. As its predecessor, this new protocol, called AntOR, is hybrid in the sense that it contains elements from both reactive and proactive routing. Specifically, it combines a reactive route setup process with a proactive route maintenance and improvement process. Key aspects of the AntOR protocol are the disjoint-link and disjoint-node routes, separation between the regular pheromone and the virtual pheromone in the diffusion process and the exploration of routes, taking into consideration the number of hops in the best routes. In this work, a family of ACO routing protocols based on AntOR is also specified. These protocols are based on protocol successive refinements. In this work, we also present a parallelized version of AntOR that we call PAntOR. Using programming multiprocessor architectures based on the shared memory protocol, PAntOR allows running tasks in parallel using threads. This parallelization is applicable in the route setup phase, route local repair process and link failure notification. In addition, a variant of PAntOR that consists of having more than one interface, which we call PAntOR-MI (PAntOR-Multiple Interface), is specified. This approach parallelizes the sending of broadcast messages by interface through threads.

Crystallization engineering as a route to epitaxial strain control

Directory of Open Access Journals (Sweden)

Andrew R. Akbashev

2015-10-01

Full Text Available The controlled synthesis of epitaxial thin films offers opportunities for tuning their functional properties via enabling or suppressing strain relaxation. Examining differences in the epitaxial crystallization of amorphous oxide films, we report on an alternate, low-temperature route for strain engineering. Thin films of amorphous Bi–Fe–O were grown on (001SrTiO3 and (001LaAlO3 substrates via atomic layer deposition. In situ X-ray diffraction and X-ray photoelectron spectroscopy studies of the crystallization of the amorphous films into the epitaxial (001BiFeO3 phase reveal distinct evolution profiles of crystallinity with temperature. While growth on (001SrTiO3 results in a coherently strained film, the same films obtained on (001LaAlO3 showed an unstrained, dislocation-rich interface, with an even lower temperature onset of the perovskite phase crystallization than in the case of (001SrTiO3. Our results demonstrate how the strain control in an epitaxial film can be accomplished via its crystallization from the amorphous state.

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.

Hazardous materials routing - risk management of mismanagement

International Nuclear Information System (INIS)

Glickman, T.S.

1988-01-01

Along with emergency planning and preparedness, the placement of restrictions on routing has become an increasingly popular device for managing the highway and rail risks of hazardous materials transportation. Federal studies conducted in 1985 indicate that at that time there were 513 different state and local restrictions on the routing of hazardous materials for these two modes of transportation, and that there were 136 state and local notification requirements, that is, restrictions that take the form of a statute or ordinance requiring advance warning or periodic reporting about hazardous materials shipments. Routing restrictions also take the form of prohibiting the use of road, a tunnel, or a bridge for a specified set of hazardous materials

Direct Z-scheme TiO2/CdS hierarchical photocatalyst for enhanced photocatalytic H2-production activity

Science.gov (United States)

Meng, Aiyun; Zhu, Bicheng; Zhong, Bo; Zhang, Liuyang; Cheng, Bei

2017-11-01

Photocatalytic H2 evolution, which utilizes solar energy via water splitting, is a promising route to deal with concerns about energy and environment. Herein, a direct Z-scheme TiO2/CdS binary hierarchical photocatalyst was fabricated via a successive ionic layer adsorption and reaction (SILAR) technique, and photocatalytic H2 production was measured afterwards. The as-prepared TiO2/CdS hybrid photocatalyst exhibited noticeably promoted photocatalytic H2-production activity of 51.4 μmol h-1. The enhancement of photocatalytic activity was ascribed to the hierarchical structure, as well as the efficient charge separation and migration from TiO2 nanosheets to CdS nanoparticles (NPs) at their tight contact interfaces. Moreover, the direct Z-scheme photocatalytic reaction mechanism was demonstrated to elucidate the improved photocatalytic performance of TiO2/CdS composite photocatalyst. The photoluminescence (PL) analysis of hydroxyl radicals were conducted to provide clues for the direct Z-scheme mechanism. This work provides a facile route for the construction of redox mediator-free Z-scheme photocatalytic system for photocatalytic water splitting.

Evaluation of geocast routing trees on random and actual networks

NARCIS (Netherlands)

Meijerink, Berend Jan; Baratchi, Mitra; Heijenk, Geert; Koucheryavy, Yevgeni; Mamatas, Lefteris; Matta, Ibrahim; Ometov, Aleksandr; Papadimitriou, Panagiotis

2017-01-01

Efficient geocast routing schemes are needed to transmit messages to mobile networked devices in geographically scoped areas. To design an efficient geocast routing algorithm a comprehensive evaluation of different routing tree approaches is needed. In this paper, we present an analytical study

Energy Reduction Multipath Routing Protocol for MANET Using Recoil Technique

Directory of Open Access Journals (Sweden)

Rakesh Kumar Sahu

2018-04-01

Full Text Available In Mobile Ad-hoc networks (MANET, power conservation and utilization is an acute problem and has received significant attention from academics and industry in recent years. Nodes in MANET function on battery power, which is a rare and limited energy resource. Hence, its conservation and utilization should be done judiciously for the effective functioning of the network. In this paper, a novel protocol namely Energy Reduction Multipath Routing Protocol for MANET using Recoil Technique (AOMDV-ER is proposed, which conserves the energy along with optimal network lifetime, routing overhead, packet delivery ratio and throughput. It performs better than any other AODV based algorithms, as in AOMDV-ER the nodes transmit packets to their destination smartly by using a varying recoil off time technique based on their geographical location. This concept reduces the number of transmissions, which results in the improvement of network lifetime. In addition, the local level route maintenance reduces the additional routing overhead. Lastly, the prediction based link lifetime of each node is estimated which helps in reducing the packet loss in the network. This protocol has three subparts: an optimal route discovery algorithm amalgamation with the residual energy and distance mechanism; a coordinated recoiled nodes algorithm which eliminates the number of transmissions in order to reduces the data redundancy, traffic redundant, routing overhead, end to end delay and enhance the network lifetime; and a last link reckoning and route maintenance algorithm to improve the packet delivery ratio and link stability in the network. The experimental results show that the AOMDV-ER protocol save at least 16% energy consumption, 12% reduction in routing overhead, significant achievement in network lifetime and packet delivery ratio than Ad hoc on demand multipath distance vector routing protocol (AOMDV, Ad hoc on demand multipath distance vector routing protocol life

A Multicast Protocol Utilizing On-demand Routing Strategy for MPRN

Institute of Scientific and Technical Information of China (English)

无

2002-01-01

This paper proposes a multicast protocol utilizing ondemand routing strategy for mobile packet radio network. It does not maintain permanent route tables with full topological views. Instead, multicast senders apply on-demand procedures to dynamically discover routes and build forwarding group in this protocol. The data packets are propagated by each forwarding group member via scoped flooding, so the protocol can reduce network bandwidth overhead and avoid the propagation of potentially large routing updates throughout the network.

An Evolutionary Real-Time 3D Route Planner for Aircraft

Institute of Scientific and Technical Information of China (English)

郑昌文; 丁明跃; 周成平

2003-01-01

A novel evolutionary route planner for aircraft is proposed in this paper. In the new planner, individual candidates are evaluated with respect to the workspace, thus the computation of the configuration space is not required. By using problem-specific chromosome structure and genetic operators, the routes are generated in real time,with different mission constraints such as minimum route leg length and flying altitude, maximum turning angle, maximum climbing/diving angle and route distance constraint taken into account.

CBHRP: A Cluster Based Routing Protocol for Wireless Sensor Network

OpenAIRE

Rashed, M. G.; Kabir, M. Hasnat; Rahim, M. Sajjadur; Ullah, Sk. Enayet

2012-01-01

A new two layer hierarchical routing protocol called Cluster Based Hierarchical Routing Protocol (CBHRP) is proposed in this paper. It is an extension of LEACH routing protocol. We introduce cluster head-set idea for cluster-based routing where several clusters are formed with the deployed sensors to collect information from target field. On rotation basis, a head-set member receives data from the neighbor nodes and transmits the aggregated results to the distance base station. This protocol ...

Routing - a preliminary study of the use of modern information and communication technology

International Nuclear Information System (INIS)

Stjernman, G.

1992-01-01

Communication and data transfer to mobile equipment are in a very active developing face. These technologies might be useful in the work on enhancing the safety of dangerous goods transports. The risk at a certain place, when passed by a transport of dangerous goods, is not the same at every moment. Taking this into account when selecting roads for dangerous goods vehicles so that, for every vehicle, the road most suited at the time in question is selected, should give better results than todays practise. The principles of dynamic routeing of dangerous goods are discussed and the needed and available technologies for implementing dynamic routeing are outlined, as are some other aspects of the implementation. (au)

A lower bound for the node, edge, and arc routing problem

DEFF Research Database (Denmark)

Bach, Lukas; Hasle, Geir; Wøhlk, Sanne

2013-01-01

The Node, Edge, and Arc Routing Problem (NEARP) was defined by Prins and Bouchenoua in 2004, although similar problems have been studied before. This problem, also called the Mixed Capacitated General Routing Problem (MCGRP), generalizes the classical Capacitated Vehicle Routing Problem (CVRP......), the Capacitated Arc Routing Problem (CARP), and the General Routing Problem. It captures important aspects of real-life routing problems that were not adequately modeled in previous Vehicle Routing Problem (VRP) variants. The authors also proposed a memetic algorithm procedure and defined a set of test instances...... called the CBMix benchmark. The NEARP definition and investigation contribute to the development of rich VRPs. In this paper we present the first lower bound procedure for the NEARP. It is a further development of lower bounds for the CARP. We also define two novel sets of test instances to complement...

Interval Routing and Minor-Monotone Graph Parameters

NARCIS (Netherlands)

Bakker, E.M.; Bodlaender, H.L.; Tan, R.B.; Leeuwen, J. van

2006-01-01

We survey a number of minor-monotone graph parameters and their relationship to the complexity of routing on graphs. In particular we compare the interval routing parameters κslir(G) and κsir(G) with Colin de Verdi`ere’s graph invariant μ(G) and its variants λ(G) and κ(G). We show that for all the

Indoor 3D Route Modeling Based On Estate Spatial Data

Science.gov (United States)

Zhang, H.; Wen, Y.; Jiang, J.; Huang, W.

2014-04-01

Indoor three-dimensional route model is essential for space intelligence navigation and emergency evacuation. This paper is motivated by the need of constructing indoor route model automatically and as far as possible. By comparing existing building data sources, this paper firstly explained the reason why the estate spatial management data is chosen as the data source. Then, an applicable method of construction three-dimensional route model in a building is introduced by establishing the mapping relationship between geographic entities and their topological expression. This data model is a weighted graph consist of "node" and "path" to express the spatial relationship and topological structure of a building components. The whole process of modelling internal space of a building is addressed by two key steps: (1) each single floor route model is constructed, including path extraction of corridor using Delaunay triangulation algorithm with constrained edge, fusion of room nodes into the path; (2) the single floor route model is connected with stairs and elevators and the multi-floor route model is eventually generated. In order to validate the method in this paper, a shopping mall called "Longjiang New City Plaza" in Nanjing is chosen as a case of study. And the whole building space is constructed according to the modelling method above. By integrating of existing path finding algorithm, the usability of this modelling method is verified, which shows the indoor three-dimensional route modelling method based on estate spatial data in this paper can support indoor route planning and evacuation route design very well.

HIGHWAY, a transportation routing model: program description and users' manual

International Nuclear Information System (INIS)

Joy, D.S.; Johnson, P.E.; Gibson, S.M.

1982-12-01

A computerized transportation routing model has been developed at the Oak Ridge National Laboratory to be used for predicting likely routes for shipping radioactive materials. The HIGHWAY data base is a computerized road atlas containing descriptions of the entire interstate highway system, the federal highway system, and most of the principal state roads. In addition to its prediction of the most likely commercial route, options incorporated in the HIGHWAY model can allow for maximum use of interstate highways or routes that will bypass urbanized areas containing populations > 100,000. The user may also interactively modify the data base to predict routes that bypass any particular state, city, town, or specific highway segment

Dynamic Routing of Aircraft in the Presence of Adverse Weather Using a POMDP Framework

Science.gov (United States)

Balaban, Edward; Roychoudhury, Indranil; Spirkovska, Lilly; Sankararaman, Shankar; Kulkarni, Chetan; Arnon, Tomer

2017-01-01

Each year weather-related airline delays result in hundreds of millions of dollars in additional fuel burn, maintenance, and lost revenue, not to mention passenger inconvenience. The current approaches for aircraft route planning in the presence of adverse weather still mainly rely on deterministic methods. In contrast, this work aims to deal with the problem using a Partially Observable Markov Decision Processes (POMDPs) framework, which allows for reasoning over uncertainty (including uncertainty in weather evolution over time) and results in solutions that are more robust to disruptions. The POMDP-based decision support system is demonstrated on several scenarios involving convective weather cells and is benchmarked against a deterministic planning system with functionality similar to those currently in use or under development.

Structure of a Highly Active Cephalopod S-crystallin Mutant: New Molecular Evidence for Evolution from an Active Enzyme into Lens-Refractive Protein.

Science.gov (United States)

Tan, Wei-Hung; Cheng, Shu-Chun; Liu, Yu-Tung; Wu, Cheng-Guo; Lin, Min-Han; Chen, Chiao-Che; Lin, Chao-Hsiung; Chou, Chi-Yuan

2016-08-08

Crystallins are found widely in animal lenses and have important functions due to their refractive properties. In the coleoid cephalopods, a lens with a graded refractive index provides good vision and is required for survival. Cephalopod S-crystallin is thought to have evolved from glutathione S-transferase (GST) with various homologs differentially expressed in the lens. However, there is no direct structural information that helps to delineate the mechanisms by which S-crystallin could have evolved. Here we report the structural and biochemical characterization of novel S-crystallin-glutathione complex. The 2.35-Å crystal structure of a S-crystallin mutant from Octopus vulgaris reveals an active-site architecture that is different from that of GST. S-crystallin has a preference for glutathione binding, although almost lost its GST enzymatic activity. We've also identified four historical mutations that are able to produce a "GST-like" S-crystallin that has regained activity. This protein recapitulates the evolution of S-crystallin from GST. Protein stability studies suggest that S-crystallin is stabilized by glutathione binding to prevent its aggregation; this contrasts with GST-σ, which do not possess this protection. We suggest that a tradeoff between enzyme activity and the stability of the lens protein might have been one of the major driving force behind lens evolution.

Routing of Electric Vehicles: City Distribution in Copenhagen

DEFF Research Database (Denmark)

Linde, Esben; Larsen, Allan; Nørrelund, Anders Vedsted

In this work, a Vehicle Routing Problem with Time Windows considering EV constraints of limited driving range and freight capacity is addressed (EVRPTW). The EVs are allowed to recharge at certain locations, and aspects of intelligent location of these recharging points are considered....... The objective is to find the least cost plan for EV routing and compare this to conventional routing. A heuristic method is developed and tested on data based on real-life collected data on distribution vehicles in central Copenhagen, Denmark. The EVRPTW has so far received little attention in the literature...

Energy-Aware Routing Optimization in Dynamic GMPLS Controlled Optical Networks

DEFF Research Database (Denmark)

Wang, Jiayuan; Ricciardi, Sergio; Fagertun, Anna Manolova

2012-01-01

In this paper, routing optimizations based on energy sources are proposed in dynamic GMPLS controlled optical networks. The influences of re-routing and load balancing factors on the algorithm are evaluated, with a focus on different re-routing thresholds. Results from dynamic network simulations...

Topography evolution of rough-surface metallic substrates by solution deposition planarization method

Science.gov (United States)

Chu, Jingyuan; Zhao, Yue; Liu, Linfei; Wu, Wei; Zhang, Zhiwei; Hong, Zhiyong; Li, Yijie; Jin, Zhijian

2018-01-01

As an emerging technique for surface smoothing, solution deposition planarization (SDP) has recently drawn more attention on the fabrication of the second generation high temperature superconducting (2G-HTS) tapes. In our work, a number of amorphous oxide layers were deposited on electro-polished or mirror-rolled metallic substrates by chemical solution route. Topography evolution of surface defects on these two types of metallic substrates was thoroughly investigated by atomic force microscopy (AFM). It was showed that root mean square roughness values (at 50 × 50 μm2 scanning scale) on both rough substrates reduced to ∼5 nm after coating with SDP-layer. The smoothing effect was mainly attributed to decrease of the depth at grain boundary grooving on the electro-polished metallic substrate. On the mirror-rolled metallic substrates, the amplitude and frequency of the height fluctuation perpendicular to the rolling direction were gradually reduced as depositing more numbers of SDP-layer. A high Jc value of 4.17 MA cm-2 (at 77 K, s.f.) was achieved on a full stack of YBCO/CeO2/IBAD-MgO/SDP-layer/C276 sample. This study enhanced understanding of the topography evolution on the surface defects covered by the SDP-layer, and demonstrated a low-cost route for fabricating IBAD-MgO based YBCO templates with a simplified architecture.

Direct Photonic-Plasmonic Coupling and Routing in Single Nanowires

Energy Technology Data Exchange (ETDEWEB)

Yan, Rouxue; Pausauskie, Peter; Huang, Jiaxing; Yang, Piedong

2009-10-20

Metallic nanoscale structures are capable of supporting surface plasmon polaritons (SPPs), propagating collective electron oscillations with tight spatial confinement at the metal surface. SPPs represent one of the most promising structures to beat the diffraction limit imposed by conventional dielectric optics. Ag nano wires have drawn increasing research attention due to 2D sub-100 nm mode confinement and lower losses as compared with fabricated metal structures. However, rational and versatile integration of Ag nanowires with other active and passive optical components, as well as Ag nanowire based optical routing networks, has yet to be achieved. Here, we demonstrate that SPPs can be excited simply by contacting a silver nanowire with a SnO2 nanoribbon that serves both as an unpolarized light source and a dielectric waveguide. The efficient coupling makes it possible to measure the propagation-distance-dependent waveguide spectra and frequency-dependent propagation length on a single Ag nanowire. Furthermore, we have demonstrated prototypical photonic-plasmonic routing devices, which are essential for incorporating low-loss Ag nanowire waveguides as practical components into high-capacity photonic circuits.

Anaerobic ammonia removal in presence of organic matter: A novel route

International Nuclear Information System (INIS)

Sabumon, P.C.

2007-01-01

This study describes the feasibility of anaerobic ammonia removal process in presence of organic matter. Different sources of biomass collected from diverse eco-systems containing ammonia and organic matter (OM) were screened for potential anaerobic ammonia removal. Sequential batch studies confirmed the possibility of anaerobic ammonia removal in presence of OM, but ammonia was oxidized anoxically to nitrate (at oxidation reduction potential; ORP -248 ± 25 mV) by an unknown mechanism unlike in the reported anammox process. The oxygen required for oxidation of ammonia might have been generated through catalase enzymatic activity of facultative anaerobes in mixed culture. The oxygen generation possibility by catalase enzyme route was demonstrated. Among the inorganic electron acceptors (NO 2 - , NO 3 - and SO 4 2- ) studied, NO 2 - was found to be most effective in total nitrogen removal. Denitrification by the developed culture was much effective and faster compared to ammonia oxidation. The results of this study show that anaerobic ammonia removal is feasible in presence of OM. The novel nitrogen removal route is hypothesized as enzymatic anoxic oxidation of NH 4 + to NO 3 - , followed by denitrification via autotrophic and/or heterotrophic routes. The results of batch study were confirmed in continuous reactor operation

Acquisition of business intelligence from human experience in route planning

Science.gov (United States)

Bello Orgaz, Gema; Barrero, David F.; R-Moreno, María D.; Camacho, David

2015-04-01

The logistic sector raises a number of highly challenging problems. Probably one of the most important ones is the shipping planning, i.e. plan the routes that the shippers have to follow to deliver the goods. In this article, we present an artificial intelligence-based solution that has been designed to help a logistic company to improve its routes planning process. In order to achieve this goal, the solution uses the knowledge acquired by the company drivers to propose optimised routes. Hence, the proposed solution gathers the experience of the drivers, processes it and optimises the delivery process. The solution uses data mining to extract knowledge from the company information systems and prepares it for analysis with a case-based reasoning (CBR) algorithm. The CBR obtains critical business intelligence knowledge from the drivers experience that is needed by the planner. The design of the routes is done by a genetic algorithm that, given the processed information, optimises the routes following several objectives, such as minimise the distance or time. Experimentation shows that the proposed approach is able to find routes that improve, on average, the routes made by the human experts.

Active Edge Sites Engineering in Nickel Cobalt Selenide Solid Solutions for Highly Efficient Hydrogen Evolution

KAUST Repository

Xia, Chuan

2017-01-06

An effective multifaceted strategy is demonstrated to increase active edge site concentration in NiCoSe solid solutions prepared by in situ selenization process of nickel cobalt precursor. The simultaneous control of surface, phase, and morphology result in as-prepared ternary solid solution with extremely high electrochemically active surface area (C = 197 mF cm), suggesting significant exposure of active sites in this ternary compound. Coupled with metallic-like electrical conductivity and lower free energy for atomic hydrogen adsorption in NiCoSe, identified by temperature-dependent conductivities and density functional theory calculations, the authors have achieved unprecedented fast hydrogen evolution kinetics, approaching that of Pt. Specifically, the NiCoSe solid solutions show a low overpotential of 65 mV at -10 mV cm, with onset potential of mere 18 mV, an impressive small Tafel slope of 35 mV dec, and a large exchange current density of 184 μA cm in acidic electrolyte. Further, it is shown that the as-prepared NiCoSe solid solution not only works very well in acidic electrolyte but also delivers exceptional hydrogen evolution reaction (HER) performance in alkaline media. The outstanding HER performance makes this solid solution a promising candidate for mass hydrogen production.

Non-Fermi Liquids as Highly Active Oxygen Evolution Reaction Catalysts.

Science.gov (United States)

Hirai, Shigeto; Yagi, Shunsuke; Chen, Wei-Tin; Chou, Fang-Cheng; Okazaki, Noriyasu; Ohno, Tomoya; Suzuki, Hisao; Matsuda, Takeshi

2017-10-01

The oxygen evolution reaction (OER) plays a key role in emerging energy conversion technologies such as rechargeable metal-air batteries, and direct solar water splitting. Herein, a remarkably low overpotential of ≈150 mV at 10 mA cm -2 disk in alkaline solutions using one of the non-Fermi liquids, Hg 2 Ru 2 O 7 , is reported. Hg 2 Ru 2 O 7 displays a rapid increase in current density and excellent durability as an OER catalyst. This outstanding catalytic performance is realized through the coexistence of localized d-bands with the metallic state that is unique to non-Fermi liquids. The findings indicate that non-Fermi liquids could greatly improve the design of highly active OER catalysts.

Secure Trust Based Key Management Routing Framework for Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Jugminder Kaur

2016-01-01

Full Text Available Security is always a major concern in wireless sensor networks (WSNs. Several trust based routing protocols are designed that play an important role in enhancing the performance of a wireless network. However they still have some disadvantages like limited energy resources, susceptibility to physical capture, and little protection against various attacks due to insecure wireless communication channels. This paper presents a secure trust based key management (STKF routing framework that establishes a secure trustworthy route depending upon the present and past node to node interactions. This route is then updated by isolating the malicious or compromised nodes from the route, if any, and a dedicated link is created between every pair of nodes in the selected route with the help of “q” composite random key predistribution scheme (RKPS to ensure data delivery from source to destination. The performance of trust aware secure routing framework (TSRF is compared with the proposed routing scheme. The results indicate that STKF provides an effective mechanism for finding out a secure route with better trustworthiness than TSRF which avoids the data dropping, thereby increasing the data delivery ratio. Also the distance required to reach the destination in the proposed protocol is less hence effectively utilizing the resources.

Geomorphology, active tectonics, and landscape evolution in the Mid-Atlantic region: Chapter

Science.gov (United States)

Pazzaglia, Frank J.; Carter, Mark W.; Berti, Claudio; Counts, Ronald C.; Hancock, Gregory S.; Harbor, David; Harrison, Richard W.; Heller, Matthew J.; Mahan, Shannon; Malenda, Helen; McKeon, Ryan; Nelson, Michelle S.; Prince, Phillip; Rittenour, Tammy M.; Spotilla, James; Whittecar, G. Richard

2015-01-01

In 2014, the geomorphology community marked the 125th birthday of one of its most influential papers, “The Rivers and Valleys of Pennsylvania” by William Morris Davis. Inspired by Davis’s work, the Appalachian landscape rapidly became fertile ground for the development and testing of several grand landscape evolution paradigms, culminating with John Hack’s dynamic equilibrium in 1960. As part of the 2015 GSA Annual Meeting, the Geomorphology, Active Tectonics, and Landscape Evolution field trip offers an excellent venue for exploring Appalachian geomorphology through the lens of the Appalachian landscape, leveraging exciting research by a new generation of process-oriented geomorphologists and geologic field mapping. Important geomorphologic scholarship has recently used the Appalachian landscape as the testing ground for ideas on long- and short-term erosion, dynamic topography, glacial-isostatic adjustments, active tectonics in an intraplate setting, river incision, periglacial processes, and soil-saprolite formation. This field trip explores a geologic and geomorphic transect of the mid-Atlantic margin, starting in the Blue Ridge of Virginia and proceeding to the east across the Piedmont to the Coastal Plain. The emphasis here will not only be on the geomorphology, but also the underlying geology that establishes the template and foundation upon which surface processes have etched out the familiar Appalachian landscape. The first day focuses on new and published work that highlights Cenozoic sedimentary deposits, soils, paleosols, and geomorphic markers (terraces and knickpoints) that are being used to reconstruct a late Cenozoic history of erosion, deposition, climate change, and active tectonics. The second day is similarly devoted to new and published work documenting the fluvial geomorphic response to active tectonics in the Central Virginia seismic zone (CVSZ), site of the 2011 M 5.8 Mineral earthquake and the integrated record of Appalachian

Application of cloud computing in power routing for clusters of microgrids using oblivious network routing algorithm

DEFF Research Database (Denmark)

Amini, M. Hadi; Broojeni, Kianoosh G.; Dragicevic, Tomislav

2017-01-01

of microgrid while preventing congestion as well as minimizing the power loss. Then, we present a two-layer simulation platform which considers both communication layer and physical layer of the microgrids' cluster. In order to improve the security of communication network, we perform the computations...... regarding the oblivious power routing via a cloud-based network. The proposed framework can be used for further studies that deal with the real-time simulation of the clusters of microgrids. In order to validate the effectiveness of the proposed framework, we implement our proposed oblivious routing scheme...

Active site loop conformation regulates promiscuous activity in a lactonase from Geobacillus kaustophilus HTA426.

Directory of Open Access Journals (Sweden)

Yu Zhang

Full Text Available Enzyme promiscuity is a prerequisite for fast divergent evolution of biocatalysts. A phosphotriesterase-like lactonase (PLL from Geobacillus kaustophilus HTA426 (GkaP exhibits main lactonase and promiscuous phosphotriesterase activities. To understand its catalytic and evolutionary mechanisms, we investigated a "hot spot" in the active site by saturation mutagenesis as well as X-ray crystallographic analyses. We found that position 99 in the active site was involved in substrate discrimination. One mutant, Y99L, exhibited 11-fold improvement over wild-type in reactivity (kcat/Km toward the phosphotriesterase substrate ethyl-paraoxon, but showed 15-fold decrease toward the lactonase substrate δ-decanolactone, resulting in a 157-fold inversion of the substrate specificity. Structural analysis of Y99L revealed that the mutation causes a ∼6.6 Å outward shift of adjacent loop 7, which may cause increased flexibility of the active site and facilitate accommodation and/or catalysis of organophosphate substrate. This study provides for the PLL family an example of how the evolutionary route from promiscuity to specificity can derive from very few mutations, which promotes alteration in the conformational adjustment of the active site loops, in turn draws the capacity of substrate binding and activity.

Optimization Model for Headway of a Suburban Bus Route

Directory of Open Access Journals (Sweden)

Xiaohong Jiang

2014-01-01

Full Text Available Due to relatively low passenger demand, headways of suburban bus route are usually longer than those of urban bus route. Actually it is also difficult to balance the benefits between passengers and operators, subject to the service standards from the government. Hence the headway of a suburban bus route is usually determined on the empirical experience of transport planners. To cope with this problem, this paper proposes an optimization model for designing the headways of suburban bus routes by minimizing the operating and user costs. The user costs take into account both the waiting time cost and the crowding cost. The feasibility and validity of the proposed model are shown by applying it to the Route 206 in Jiangning district, Nanjing city of China. Weightages of passengers’ cost and operating cost are further discussed, considering different passenger flows. It is found that the headway and objective function are affected by the weightages largely.

Transmission Scheduling and Routing Algorithms for Delay Tolerant Networks

Science.gov (United States)

Dudukovich, Rachel; Raible, Daniel E.

2016-01-01

The challenges of data processing, transmission scheduling and routing within a space network present a multi-criteria optimization problem. Long delays, intermittent connectivity, asymmetric data rates and potentially high error rates make traditional networking approaches unsuitable. The delay tolerant networking architecture and protocols attempt to mitigate many of these issues, yet transmission scheduling is largely manually configured and routes are determined by a static contact routing graph. A high level of variability exists among the requirements and environmental characteristics of different missions, some of which may allow for the use of more opportunistic routing methods. In all cases, resource allocation and constraints must be balanced with the optimization of data throughput and quality of service. Much work has been done researching routing techniques for terrestrial-based challenged networks in an attempt to optimize contact opportunities and resource usage. This paper examines several popular methods to determine their potential applicability to space networks.

An Adaptive Clustering Approach Based on Minimum Travel Route Planning for Wireless Sensor Networks with a Mobile Sink.

Science.gov (United States)

Tang, Jiqiang; Yang, Wu; Zhu, Lingyun; Wang, Dong; Feng, Xin

2017-04-26

In recent years, Wireless Sensor Networks with a Mobile Sink (WSN-MS) have been an active research topic due to the widespread use of mobile devices. However, how to get the balance between data delivery latency and energy consumption becomes a key issue of WSN-MS. In this paper, we study the clustering approach by jointly considering the Route planning for mobile sink and Clustering Problem (RCP) for static sensor nodes. We solve the RCP problem by using the minimum travel route clustering approach, which applies the minimum travel route of the mobile sink to guide the clustering process. We formulate the RCP problem as an Integer Non-Linear Programming (INLP) problem to shorten the travel route of the mobile sink under three constraints: the communication hops constraint, the travel route constraint and the loop avoidance constraint. We then propose an Imprecise Induction Algorithm (IIA) based on the property that the solution with a small hop count is more feasible than that with a large hop count. The IIA algorithm includes three processes: initializing travel route planning with a Traveling Salesman Problem (TSP) algorithm, transforming the cluster head to a cluster member and transforming the cluster member to a cluster head. Extensive experimental results show that the IIA algorithm could automatically adjust cluster heads according to the maximum hops parameter and plan a shorter travel route for the mobile sink. Compared with the Shortest Path Tree-based Data-Gathering Algorithm (SPT-DGA), the IIA algorithm has the characteristics of shorter route length, smaller cluster head count and faster convergence rate.

Influence of the Built Environment on Pedestrian Route Choices of Adolescent Girls

DEFF Research Database (Denmark)

Rodriguez, Daniel A.; Merlin, Louis; Prato, Carlo Giacomo

2015-01-01

We examined the influence of the built environment on pedestrian route selection among adolescent girls. Portable global positioning system units, accelerometers, and travel diaries were used to identify the origin, destination, and walking routes of girls in San Diego, California, and Minneapolis...... of route choice. Shorter distance had the strongest positive association with route choice, whereas the presence of a greenway or trail, higher safety, presence of sidewalks, and availability of destinations along a route were also consistently positively associated with route choice at both sites...

Comparison of MANET routing protocols using a scaled indoor wireless grid

CSIR Research Space (South Africa)

Johnson, DL

2008-04-01

Full Text Available accumulation feature of Dynamic Source Routing (DSR) by adding the accumulated route, back to the source, to the Route Request packet. It retains the destination sequence number feature of AODV but HELLO packets are an optional feature and are normally left... than the inbound traffic as the routing algorithm makes a decision to rebroadcast the packet or not and Figure 20 confirms this. DYMO shows the least amount of routing traffic due to its lack of HELLO packets. This is also due to no further...

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

Science.gov (United States)

2012-09-06

...-0749; Airspace Docket No. 11-ANM-29] 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-528... 20591; telephone: (202) 267-8783. SUPPLEMENTARY INFORMATION: Background Jet Route J-528 is currently...

On the Core of Routing Games with Revenues

NARCIS (Netherlands)

A. Estévez-Fernandéz (Arantza); P. Borm; M. Meertens; H. Reijnierse

2006-01-01

htmlabstract Traveling salesman problems with revenues form a generalization of traveling salesman problems. Here, next to travel costs an explicit revenue is generated by visiting a city. We analyze routing problems with revenues, where a predetermined route on all cities determines the tours

On the Core of Routing Games with Revenues

NARCIS (Netherlands)

Estevez Fernandez, M.A.; Borm, P.E.M.; Meertens, M.; Reijnierse, J.H.

2006-01-01

Traveling salesman problems with revenues form a generalization of traveling salesman problems.Here, next to travel costs an explicit revenue is generated by visiting a city.We analyze routing problems with revenues, where a predetermined route on all cities determines the tours along

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.

Locating Depots for Capacitated Vehicle Routing

DEFF Research Database (Denmark)

Gørtz, Inge Li; Nagarajan, Viswanath

2011-01-01

that all demands are satisfied and the total cost is minimized. Our main result is a constant-factor approximation algorithm for k-LocVRP. To achieve this result, we reduce k-LocVRP to the following generalization of k median, which might be of independent interest. Given a metric (V, d), bound k...... median forest, which leads to a (12+E)-approximation algorithm for k-LocVRP, for any constant E > 0. The algorithm for k median forest is t-swap local search, and we prove that it has locality gap 3 + 2 t ; this generalizes the corresponding result for k median [3]. Finally we consider the k median......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...

ANALYSIS OF THE LICENSED TOURIST GUIDES’ EVOLUTION OF ROMANIA AND CRITICAL ISSUES AFFECTING THEIR ACTIVITY

Directory of Open Access Journals (Sweden)

Corina TĂTAR

2017-10-01

Full Text Available The study refers to the licensed tourist guides of Romania during 1998-2016, namely their numerical evolution during this time series as well as an analysis of their numerical evolution by different types of tourist guides, be they national, local or specialized. The statistical analysis showed an increment from 24 tourist guides in the year 1998 to 4,335 licensed tour guides in 2016. The analysis is supplemented by current issues and shortcomings affecting the tourist guiding activity of Romania, as revealed by the tourist guides present at the annual tourist guides’ national conferences, various stringent problems raised and debated within these encounters and highlighted by this study as well as proposals for a better functioning for this segment of tourism entrepreneurs.

Evolution of microstructure at hot band annealing of ferritic FeSi steels

Energy Technology Data Exchange (ETDEWEB)

Schneider, Jürgen, E-mail: juergen.schneider@t-online.de [Institute of Metal Forming, Technische Universität Bergakademie Freiberg, Bernhard-von Cotta-Str. 4, D-09596 Freiberg (Germany); Stahlzentrum Freiberg e.V., Leipziger Straße 34, D-09599 Freiberg (Germany); Li, Guangqiang [State Key Lab. of Refractories and Metallurgy, Wuhan University of Science and Technology, No. 947 Heping Avenue, Qingshan District, Wuhan 430081 (China); Franke, Armin [Stahlzentrum Freiberg e.V., Leipziger Straße 34, D-09599 Freiberg (Germany); Zhou, Bowen [State Key Lab. of Refractories and Metallurgy, Wuhan University of Science and Technology, No. 947 Heping Avenue, Qingshan District, Wuhan 430081 (China)

2017-02-15

The magnetic properties of the finally fabricated nonoriented FeSi steels critically depend on the microstructure and on the occurring crystallographic texture. The fabrication route comprises hot rolling, coiling and cooling, hot band annealing before cold rolling (optional), cold rolling and the final thermal treatment. As well known there is an interplay between the microstructure and texture during the various processing steps. For that reason, it is of interest to know more on the evolution of the microstructure at hot band annealing of hot band prepared in different ways. In this paper we will summarize our recent results on the evolution of microstructure during thermal annealing of hot band: thermal treatment following immediately the last pass of hot rolling or a hot band annealing as a separate processing step before cold rolling.

Identification of a carotenoid oxygenase synthesizing acyclic xanthophylls: combinatorial biosynthesis and directed evolution.

Science.gov (United States)

Mijts, Benjamin N; Lee, Pyung Cheon; Schmidt-Dannert, Claudia

2005-04-01

A carotenoid desaturase homolog from Staphylococcus aureus (CrtOx) was identified. When expressed in engineered E. coli cells synthesizing linear C(30) carotenoids, polar carotenoid products were generated, identified as aldehyde and carboxylic acid C(30) carotenoid derivatives. The major product in this engineered pathway is the fully desaturated C(30) dialdehyde carotenoid 4,4'-diapolycopen-4,4'-dial. Very low carotenoid yields were observed when CrtOx was complemented with the C(40) carotenoid lycopene pathway. But extension of an in vitro evolved pathway of the fully desaturated 2,4,2',4'-tetradehydrolycopene produced the structurally novel fully desaturated C(40) dialdehyde carotenoid 2,4,2',4'-tetradehydrolycopendial. Directed evolution of CrtOx by error-prone PCR resulted in a number of variants with higher activity on C(40) carotenoid substrates and improved product profiles. These findings may provide new biosynthetic routes to highly polar carotenoids with unique spectral properties desirable for a number of industrial and pharmaceutical applications.

Evolutionary algorithms for the Vehicle Routing Problem with Time Windows

NARCIS (Netherlands)

Bräysy, Olli; Dullaert, Wout; Gendreau, Michel

2004-01-01

This paper surveys the research on evolutionary algorithms for the Vehicle Routing Problem with Time Windows (VRPTW). The VRPTW can be described as the problem of designing least cost routes from a single depot to a set of geographically scattered points. The routes must be designed in such a way

Short-term evolution and coexistence of spots, plages and flare activity on LQ Hydrae

Science.gov (United States)

Flores Soriano, M.; Strassmeier, K. G.

2017-01-01

Aims: We aim to study the short-term evolution of the chromospheric and photospheric activity of the young, single K2 dwarf LQ Hya. Methods: Four months of quasi-simultaneous spectroscopic and photometric observations were used to study the variations of the photometric light curve, the evolution of the chromospheric activity from the Hα and Hβ lines, and the distribution of cool spots from Doppler maps. Results: During our observations one side of the star was more active than the other. The equivalent width of the Hα line from the least active hemisphere increased from ≈0.7 Å at the beginning of the observation to 1.0 Å at the end. The basal emission of the most active hemisphere remained roughly constant at EWHαt1.0 Å. Intense flare activity was observed during the first twenty days, where at least four different events were detected. The line asymmetries of the Hα line suggest that one of the flares could have produced a mass ejection with a maximum projected speed of 70kms-1. The rotational modulation of the V-band photometry showed clear anti-correlation with the chromospheric activity. The difference in brightness between the opposite hemispheres decreased from 0.m16 to 0.m09 in two months. Three spots gradually moving apart from each other are dominating the photospheric Doppler maps. The comparison between the maps and the Hα line as the star rotates reveals the spatial coexistence of chromospheric Hα emission and photospheric spots. Conclusions: Our results indicate that the active regions of LQ Hya can live for at least four months. The detected changes in the photometric light curve and the spectroscopic Doppler images seem to be more a consequence of the spatial redistribution of the active regions rather than due to changes in their strength. Only one of the active regions shows significant changes in its chromospheric emission. Based on data obtained with the STELLA robotic telescope in Tenerife, an AIP facility jointly operated by AIP

On the core of routing games with revenues

NARCIS (Netherlands)

Estevez Fernandez, M.A.; Borm, P.; Meertens, M.; Reijnierse, H.

2009-01-01

Traveling salesman problems with revenues form a generalization of traveling salesman problems. Here, next to travel costs an explicit revenue is generated by visiting a city. We analyze routing problems with revenues, where a predetermined route on all cities determines the tours along subgroups.

k-Shortest routing of trains on shunting yards

NARCIS (Netherlands)

Riezebos, Jan; van Wezel, Wout

2009-01-01

We consider the problem of designing algorithmic support for k-best routing decisions in train shunting scheduling. A study at the Netherlands Railways revealed that planners like to interact with the solution process of finding suitable routes. Two types of interaction were required: the

Reverse stream flow routing by using Muskingum models

Indian Academy of Sciences (India)

Reverse stream flow routing is a procedure that determines the upstream hydrograph given the downstream hydrograph. This paper presents the development of methodology for Muskingum models parameter estimation for reverse stream flow routing. The standard application of the Muskingum models involves calibration ...

Tourism Routes, Local Economic Promotion and Pro-Poor ...

African Journals Online (AJOL)

In southern Africa, there is growing interest in the potential for establishing tourism routes as vehicles for tourism expansion and the promotion of local economic development. This article contributes towards understanding the potential and importance of organising routes for local tourism promotion and economic ...

Parameterization of a complex landscape for a sediment routing model of the Le Sueur River, southern Minnesota

Science.gov (United States)

Belmont, P.; Viparelli, E.; Parker, G.; Lauer, W.; Jennings, C.; Gran, K.; Wilcock, P.; Melesse, A.

2008-12-01

Modeling sediment fluxes and pathways in complex landscapes is limited by our inability to accurately measure and integrate heterogeneous, spatially distributed sources into a single coherent, predictive geomorphic transport law. In this study, we partition the complex landscape of the Le Sueur River watershed into five distributed primary source types, bluffs (including strath terrace caps), ravines, streambanks, tributaries, and flat,agriculture-dominated uplands. The sediment contribution of each source is quantified independently and parameterized for use in a sand and mud routing model. Rigorous modeling of the evolution of this landscape and sediment flux from each source type requires consideration of substrate characteristics, heterogeneity, and spatial connectivity. The subsurface architecture of the Le Sueur drainage basin is defined by a layer cake sequence of fine-grained tills, interbedded with fluvioglacial sands. Nearly instantaneous baselevel fall of 65 m occurred at 11.5 ka, as a result of the catastrophic draining of glacial Lake Agassiz through the Minnesota River, to which the Le Sueur is a tributary. The major knickpoint that was generated from that event has propagated 40 km into the Le Sueur network, initiating an incised river valley with tall, retreating bluffs and actively incising ravines. Loading estimates constrained by river gaging records that bound the knick zone indicate that bluffs connected to the river are retreating at an average rate of less than 2 cm per year and ravines are incising at an average rate of less than 0.8 mm per year, consistent with the Holocene average incision rate on the main stem of the river of less than 0.6 mm per year. Ongoing work with cosmogenic nuclide sediment tracers, ground-based LiDAR, historic aerial photos, and field mapping will be combined to represent the diversity of erosional environments and processes in a single coherent routing model.

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.

Historical evolution of nuclear energy systems development and related activities in JAERI. Fission, fusion, accelerator utilization

Energy Technology Data Exchange (ETDEWEB)

Tone, Tatsuzo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2001-03-01

Overview of the historical evolution of nuclear energy systems development and related activities in JAERI is given in the report. This report reviews the research and development for light water reactor, fast breeder reactor, high temperature gas reactor, fusion reactor and utilization of accelerator-based neutron source. (author)

Efficient Routing in Wireless Sensor Networks with Multiple Sessions

OpenAIRE

Dianjie Lu; Guijuan Zhang; Ren Han; Xiangwei Zheng; Hong Liu

2014-01-01

Wireless Sensor Networks (WSNs) are subject to node failures because of limited energy and link unreliability which makes the design of routing protocols in such networks a challenging task. The multipath routing scheme is an optimal alternative to address this problem which splits the traffic across multiple paths instead of routing all the traffic along a single path. However, using more paths introduces more contentions which degrade energy efficiency. The problem becomes even more difficu...

Applied Multiprotocol Routing in IP Telephony

Directory of Open Access Journals (Sweden)

Miroslav Voznak

2010-01-01

Full Text Available The aim of the project was to create a multi-protocol system using SIP, H.323 and MGCP standards, which would ensure routing to various types of VoIP networks. The priority was to provide multi-protocol support to SIP and H.323 signalling and the support of the routing using the ENUM standard which has recently passed from the trial phase into full operation in the Czech Republic. The document describes the system's architecture and the components used. It also briefly describes ENUM.

The influence of advertisements on the conspicuity of routing information.

Science.gov (United States)

Boersema, T; Zwaga, H J

1985-12-01