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Sample records for added transportation capacity

  1. ON THE CAPACITY REGION OF WIRELESS AD HOC RELAY NETWORKS

    Dai Qinyun; Yao Wangsheng; Peng Jianmin; Su Gang

    2006-01-01

    Network capacity is a key characteristic to evaluate the performance of wireless networks. The goal of this paper is to study the capacity of wireless ad hoc relay network. In the model, there is at most ns source nodes transmitting signal simultaneously in the network and the arbitrarily complex network coding is allowed. The upper capacity bound of the network model are derived from the max-flow min-cut theorem and the lower capacity bound are obtained by the rate-distortion function for the Gaussian source. Finally, simulation results show that the upper network capacity will decrease as the number of source nodes is increased.

  2. Optimizing Local Capacity of Wireless Ad Hoc Networks

    Malik, Salman

    2011-01-01

    In this work, we evaluate local capacity of wireless ad hoc networks with several medium access protocols and identify the most optimal protocol. We define local capacity as the average information rate received by a receiver randomly located in the network. We analyzed grid pattern protocols where simultaneous transmitters are positioned in a regular grid pattern, pure ALOHA protocols where simultaneous transmitters are dispatched according to a uniform Poisson distribution and exclusion protocols where simultaneous transmitters are dispatched according to an exclusion rule such as node coloring and carrier sense protocols. Our analysis allows us to conjecture that local capacity is optimal when simultaneous transmitters are positioned in a grid pattern based on equilateral triangles and our results show that this optimal local capacity is at most double the local capacity of simple ALOHA protocol. Our results also show that node coloring and carrier sense protocols approach the optimal local capacity by an ...

  3. Capacity of Wireless Ad Hoc Networks with Opportunistic Collaborative Communications

    Simeone O

    2007-01-01

    Full Text Available Optimal multihop routing in ad hoc networks requires the exchange of control messages at the MAC and network layer in order to set up the (centralized optimization problem. Distributed opportunistic space-time collaboration (OST is a valid alternative that avoids this drawback by enabling opportunistic cooperation with the source at the physical layer. In this paper, the performance of OST is investigated. It is shown analytically that opportunistic collaboration outperforms (centralized optimal multihop in case spatial reuse (i.e., the simultaneous transmission of more than one data stream is not allowed by the transmission protocol. Conversely, in case spatial reuse is possible, the relative performance between the two protocols has to be studied case by case in terms of the corresponding capacity regions, given the topology and the physical parameters of network at hand. Simulation results confirm that opportunistic collaborative communication is a promising paradigm for wireless ad hoc networks that deserves further investigation.

  4. Capacity of Wireless Ad Hoc Networks with Opportunistic Collaborative Communications

    O. Simeone

    2007-03-01

    Full Text Available Optimal multihop routing in ad hoc networks requires the exchange of control messages at the MAC and network layer in order to set up the (centralized optimization problem. Distributed opportunistic space-time collaboration (OST is a valid alternative that avoids this drawback by enabling opportunistic cooperation with the source at the physical layer. In this paper, the performance of OST is investigated. It is shown analytically that opportunistic collaboration outperforms (centralized optimal multihop in case spatial reuse (i.e., the simultaneous transmission of more than one data stream is not allowed by the transmission protocol. Conversely, in case spatial reuse is possible, the relative performance between the two protocols has to be studied case by case in terms of the corresponding capacity regions, given the topology and the physical parameters of network at hand. Simulation results confirm that opportunistic collaborative communication is a promising paradigm for wireless ad hoc networks that deserves further investigation.

  5. Sediment transport capacity of hyperconcentrated flow

    2008-01-01

    As one of the most important components of river mechanics,sediment transport capacity of sediment-laden flows has attracted much attention from many researchers working on river mechanics and hydraulic engineering. Based on the time-averaged equation for a turbulent energy equilibrium in solid and liquid two-phase flow,an expression for the efficiency coefficient of suspended load movement was derived for the two-dimensional,steady,uniform,fully-developed turbulent flow. A new structural expression of sediment transport capacity was achieved. Using 115 runs of flume experimental data,which were obtained through two kinds of sediment transport experiments in the state of equilibrium,in combination with the basic rheological and sediment transporting characteristics of hyperconcentrated flow,the main parameters in the structural expression of sediment transport capacity were calibrated,and a new formula of sediment transport capacity for hyperconcentrated flow was developed. A large amount of field data from the Yellow River,Wuding River,and Yangtze River,etc. were adopted to verify the new formula and good agreement was obtained. These results above contribute to an improved theoretical system of river mechanics and a reliable tool for management of rivers carrying high concentration of sediments.

  6. Only adding stationary storage to vaccine supply chains may create and worsen transport bottlenecks.

    Haidari, Leila A; Connor, Diana L; Wateska, Angela R; Brown, Shawn T; Mueller, Leslie E; Norman, Bryan A; Schmitz, Michelle M; Paul, Proma; Rajgopal, Jayant; Welling, Joel S; Leonard, Jim; Claypool, Erin G; Weng, Yu-Ting; Chen, Sheng-I; Lee, Bruce Y

    2013-01-01

    Although vaccine supply chains in many countries require additional stationary storage and transport capacity to meet current and future needs, international donors tend to donate stationary storage devices far more often than transport equipment. To investigate the impact of only adding stationary storage equipment on the capacity requirements of transport devices and vehicles, we used HERMES (Highly Extensible Resource for Modeling Supply Chains) to construct a discrete event simulation model of the Niger vaccine supply chain. We measured the transport capacity requirement for each mode of transport used in the Niger vaccine cold chain, both before and after adding cold rooms and refrigerators to relieve all stationary storage constraints in the system. With the addition of necessary stationary storage, the average transport capacity requirement increased from 88% to 144% for cold trucks, from 101% to 197% for pickup trucks, and from 366% to 420% for vaccine carriers. Therefore, adding stationary storage alone may worsen or create new transport bottlenecks as more vaccines flow through the system, preventing many vaccines from reaching their target populations. Dynamic modeling can reveal such relationships between stationary storage capacity and transport constraints. PMID:23903398

  7. An Effective Capacity Estimation Scheme in IEEE802.11-based Ad Hoc Networks

    H. Zafar

    2012-11-01

    Full Text Available Capacity estimation is a key component of any admission control scheme required to support quality of serviceprovision in mobile ad hoc networks. A range of schemes have been previously proposed to estimate residualcapacity that is derived from window-based measurements of channel estimation. In this paper a simple and improvedmechanism to estimate residual capacity in IEEE802.11-based ad hoc networks is presented. The scheme proposesthe use of a ‘forgiveness’ factor to weight these previous measurements and is shown through simulation-basedevaluation to provide accurate utilizations estimation and improved residual capacity based admission control.

  8. Multi-Stage Transportation Problem With Capacity Limit

    I. Brezina; Z. Čičková; J. Pekár; M. Reiff

    2010-01-01

    The classical transportation problem can be applied in a more general way in practice. Related problems as Multi-commodity transportation problem, Transportation problems with different kind of vehicles, Multi-stage transportation problems, Transportation problem with capacity limit is an extension of the classical transportation problem considering the additional special condition. For solving such problems many optimization techniques (dynamic programming, linear programming, special algor...

  9. Two-Way Transmission Capacity of Wireless Ad-hoc Networks

    Vaze, Rahul; Kien T. Truong; Weber, Steven; Heath Jr, Robert W.

    2010-01-01

    The transmission capacity of an ad-hoc network is the maximum density of active transmitters per unit area, given an outage constraint at each receiver for a fixed rate of transmission. Most prior work on finding the transmission capacity of ad-hoc networks has focused only on one-way communication where a source communicates with a destination and no data is sent from the destination to the source. In practice, however, two-way or bidirectional data transmission is required to support contro...

  10. Impact of network structure on the capacity of wireless multihop ad hoc communication

    Krause, Wolfram; Glauche, Ingmar; Sollacher, Rudolf; Greiner, Martin

    2004-07-01

    As a representative of a complex technological system, the so-called wireless multihop ad hoc communication networks are discussed. They represent an infrastructure-less generalization of todays wireless cellular phone networks. Lacking a central control authority, the ad hoc nodes have to coordinate themselves such that the overall network performs in an optimal way. A performance indicator is the end-to-end throughput capacity. Various models, generating differing ad hoc network structure via differing transmission power assignments, are constructed and characterized. They serve as input for a generic data traffic simulation as well as some semi-analytic estimations. The latter reveal that due to the most-critical-node effect the end-to-end throughput capacity sensitively depends on the underlying network structure, resulting in differing scaling laws with respect to network size.

  11. High capacity carrier ethernet transport networks

    Rasmussen, Anders; Zhang, Jiang; Yu, Hao;

    2009-01-01

    Ethernet as a transport technology has, up to now, lacked the features such as network layer architecture, customer separation and manageability that carriers require for wide-scale deployment. However, with the advent of PBB-TE and T-MPLS, it is now possible to use Ethernet as a transport...... OAM functions, survivability and the increased bandwidth requirements of carrier class systems. This article provides an overview of PBB-TE and T-MPLS and demonstrates how IPTV services can be realized in the framework of Carrier Ethernet. In addition we provide a case study on performing bit error...

  12. Transmission Capacity of Wireless Ad Hoc Networks with Energy Harvesting Nodes

    Vaze, Rahul

    2012-01-01

    Transmission capacity of an ad hoc wireless network is analyzed when each node of the network harvests energy from nature, e.g. solar, wind, vibration etc. Transmission capacity is the maximum allowable density of nodes, satisfying a per transmitter-receiver rate, and an outage probability constraint. Energy arrivals at each node are assumed to follow a Bernoulli distribution, and each node stores energy using an energy buffer/battery. For ALOHA medium access protocol (MAP), optimal transmission probability that maximizes the transmission capacity is derived as a function of the energy arrival distribution. Game theoretic analysis is also presented for ALOHA MAP, where each transmitter tries to maximize its own throughput, and symmetric Nash equilibrium is derived. For CSMA MAP, back-off probability and outage probability are derived in terms of input energy distribution, thereby characterizing the transmission capacity.

  13. Development of high capacity transportable storage cask

    Mitsubishi Heavy Industries have developed high performance and reliable transportable storage casks, MSF series casks. The casks have employed newly developed materials that have been expressly developed to obtain long-term stability and quality. Furthermore, the casks have been employed newly designed structure to maximize payload of accommodating fuel assemblies in order to increase economic efficiency of storing spent fuels. The casks have been applied the following technologies. Basket assembly of the cask is made of newly developed boronated aluminum. The boronated aluminum is manufactured by power metallurgy process to provide uniformity of metallic structure and artificial aging which causes deterioration under high temperature condition is not applied to provide the boronated aluminum with high stability for long-term use. For the cask for BWR fuel, simplified basket whose design is that basket consists of some individual squire pipes without assembling is adopted in the cask. Neutron shielding material of the cask is made of newly resin of which raw materials have been modified to improve durability. Monolithic forging method which is how to shape steel into vessel form is developed to skip welding process between body shell and base plate and to improve reliability. Internal face of the body forging is machined to provide steps' in its cross section in order to fit the external shape of basket assembly and so heat dissipation performance is greatly improved. The new technologies have been done demonstration test in order to confirm that MSF series casks satisfy transport regulations. (author)

  14. Upper Bounding Service Capacity in Multihop Wireless SSMA-Based Ad Hoc Networks

    Du, Shirong; Daigle, John N.; Alidaee, Bahram

    Upper bounds on the service carrying capacity of a multihop, wireless, SSMA-based ad hoc network are considered herein. The network has a single radio band for transmission and reception. Each node can transmit to, or receive from, multiple nodes simultaneously. We formulate the scheduling of transmissions and control of transmit powers as a joint, mixed-integer, nonlinear optimization problem that yields maximum return at minimum power subject to SINR constraints. We present an efficient tabu search-based heuristic algorithm to solve the optimization problem and rigorously assess the quality of the results. Through analysis and simulation, we establish upper bounds on the VoIP call carrying capacity of the network as function of various parameters. We discuss the pros and cons of using SSMA as a spectrum sharing technique in wireless ad hoc networks

  15. Asymptotic Capacity of Wireless Ad Hoc Networks with Realistic Links under a Honey Comb Topology

    Asnani, Himanshu

    2007-01-01

    We consider the effects of Rayleigh fading and lognormal shadowing in the physical interference model for all the successful transmissions of traffic across the network. New bounds are derived for the capacity of a given random ad hoc wireless network that reflect packet drop or capture probability of the transmission links. These bounds are based on a simplified network topology termed as honey-comb topology under a given routing and scheduling scheme.

  16. On capacity of wireless ad hoc networks with MIMO MMSE receivers

    Ma, Jing

    2008-01-01

    Widely adopted at home, business places, and hot spots, wireless ad-hoc networks are expected to provide broadband services parallel to their wired counterparts in near future. To address this need, MIMO techniques, which are capable of offering several-fold increase in capacity, hold significant promise. Most previous work on capacity analysis of ad-hoc networks is based on an implicit assumption that each node has only one antenna. Core to the analysis therein is the characterization of a geometric area, referred to as the exclusion region, which quantizes the amount of spatial resource occupied by a link. When multiple antennas are deployed at each node, however, multiple links can transmit in the vicinity of each other simultaneously, as interference can now be suppressed by spatial signal processing. As such, a link no longer exclusively occupies a geometric area, making the concept of "exclusion region" not applicable any more. In this paper, we investigate link-layer throughput capacity of MIMO ad-hoc ...

  17. Determinants of Capacity Utilization in Road Freight Transportation

    Abate, Megersa Abera

    2014-01-01

    Recent performance figures in the European road freight transport sector show that there is an excess capacity. To shed light on this phenomenon, this paper studies two aspects of capacity utilization in trucking: the extent of empty running and the load factor. The paper shows that they can be...... information about operations at a trip level. The results indicate that trip distance and being a for-hire carrier have a significant positive effect on capacity utilization, whereas the effect of truck size appears to be non-linear. To the extent that these variables improve the load factor and reduce empty...

  18. Capacity Utilisation of Vehicles for Road Freight Transport

    Kveiborg, Ole; Abate, Megersa Abera

    Purpose This chapter discusses a central aspect of freight transportcapacity utilisation with a link to empty running of commercial freight vehicles. Methodology/approach The paper provides an overview of the literature on these topics and groups the contributions into two segments according to...... their analytical approach and origin of research. Findings The first approach looks at utilisation based on economic theories such as the firms’ objective to maximise profitability and considers how various firm and haul (market) characteristics influence utilisation. The second approach stems from the...... transport modelling literature and its main aim is analysing vehicle movement and usage in transport demand modelling context. A strand of this second group of contributions is the modelling of trip-chain and its implication on the level of capacity utilisation. Research limitations The review is not a...

  19. High thermal-transport capacity heat pipes for space radiators

    Carlson, Albert W.; Gustafson, Eric; Roukis, Susan L.

    1987-01-01

    This paper presents the results of performance tests of several dual-slot heat pipe test articles. The dual-slot configuration has a very high thermal transport capability and has been identified as a very promising candidate for the radiator system for the NASA Space Station solar dynamic power modules. Two six-foot long aluminum heat pipes were built and tested with ammonia and acetone. A 20-ft long heat pipe was also built and tested with ammonia. The test results have been compared with performance predictions. A thermal transport capacity of 2000 W at an adverse tilt of 1 in. and a 1000 W capacity at an adverse tilt of 2 in. were achieved on the 20-ft long heat pipe. These values are in close agreement with the predicted performance limits.

  20. Effects of exercise training on coronary transport capacity

    Coronary transport capacity was estimated in eight sedentary control and eight exercise-trained anesthetized dogs by determining the differences between base line and the highest coronary blood flow and permeability-surface area product (PS) obtained during maximal adenosine vasodilation with coronary perfusion pressure constant. The anterior descending branch of the left coronary artery was cannulated and pump- perfused under constant-pressure conditions (approximately equal to 100 Torr) while aortic, central venous, and coronary perfusion pressures, heart rate, electrocardiogram, and coronary flow were monitored. Myocardial extraction and PS of 51Cr-labeled ethylenediaminetetraacetic acid were determined with the single-injection indicator-diffusion method. The efficacy of the 16 +/- 1 wk exercise training program was shown by significant increases in the succinate dehydrogenase activities of the gastrocnemius, gluteus medialis, and long head of triceps brachii muscles. There were no differences between control and trained dogs for either resting coronary blood flow or PS. During maximal vasodilation with adenosine, the trained dogs had significantly lower perfusion pressures with constant flow and, with constant-pressure vasodilation, greater coronary blood flow and PS. It is concluded that exercise training in dogs induces an increased coronary transport capacity that includes increases in coronary blood flow capacity (26% of control) and capillary diffusion capacity (82% of control)

  1. Improving gas-fired heat pump capacity and performance by adding a desiccant dehumidification subsystem

    Parsons, B.K.; Pesaran, A.A.; Bharathan, D.; Shelpuk, B.C.

    1988-09-01

    This paper examines the merits of coupling a desiccant dehumidification subsystem to a gas-engine-driven vapor compression air conditioner. A system is identified that uses a rotary silicia-gel parallel-plate dehumidifier. Dehumidifier data and analysis are based on recent tests. The dehumidification subsystem processes the fresh air portion and handles the latent portion of the load. Adding the desiccant subsystem increases the gas-based coefficient of performance 40% and increases the cooling capacity 50%. Increased initial manufacturing costs are estimated at around $500/ton ($142/kW) for volume production. This cost level is expected to reduce the total initial cost per ton compared to a system without the desiccant subsystem. 19 refs., 8 figs., 5 tabs.

  2. Effect of endurance training on glucose transport capacity and glucose transporter expression in rat skeletal muscle

    Ploug, T; Stallknecht, B M; Pedersen, O;

    1990-01-01

    increase of approximately 33% for contraction-stimulated transport in slow-twitch red fibers compared with nonexercised sedentary muscle. A fully additive effect of insulin and contractions was observed both in trained and untrained muscle. Compared with transport in control rats subjected to an almost...... exhaustive single exercise session the day before experiment both maximum insulin- and contraction-stimulated transport rates were increased in all muscle types in trained rats. Accordingly, the increased glucose transport capacity in trained muscle was not due to a residual effect of the last training...... session. Half-times for reversal of contraction-induced glucose transport were similar in trained and untrained muscles. The concentrations of mRNA for GLUT-1 (the erythrocyte-brain-Hep G2 glucose transporter) and GLUT-4 (the adipocyte-muscle glucose transporter) were increased approximately twofold by...

  3. Effect of endurance training on glucose transport capacity and glucose transporter expression in rat skeletal muscle

    The effect of 10 wk endurance swim training on 3-O-methylglucose (3-MG) uptake (at 40 mM 3-MG) in skeletal muscle was studied in the perfused rat hindquarter. Training resulted in an increase of approximately 33% for maximum insulin-stimulated 3-MG transport in fast-twitch red fibers and an increase of approximately 33% for contraction-stimulated transport in slow-twitch red fibers compared with nonexercised sedentary muscle. A fully additive effect of insulin and contractions was observed both in trained and untrained muscle. Compared with transport in control rats subjected to an almost exhaustive single exercise session the day before experiment both maximum insulin- and contraction-stimulated transport rates were increased in all muscle types in trained rats. Accordingly, the increased glucose transport capacity in trained muscle was not due to a residual effect of the last training session. Half-times for reversal of contraction-induced glucose transport were similar in trained and untrained muscles. The concentrations of mRNA for GLUT-1 (the erythrocyte-brain-Hep G2 glucose transporter) and GLUT-4 (the adipocyte-muscle glucose transporter) were increased approximately twofold by training in fast-twitch red muscle fibers. In parallel to this, Western blot demonstrated a approximately 47% increase in GLUT-1 protein and a approximately 31% increase in GLUT-4 protein. This indicates that the increases in maximum velocity for 3-MG transport in trained muscle is due to an increased number of glucose transporters

  4. Lactate/H+ transport kinetics in rat skeletal muscle related to fibre type and changes in transport capacity

    Juel; Pilegaard

    1998-01-01

    Lactate/H+ transport kinetics were determined by means of the pH-sensitive probe BCECF in sarcolemmal giant vesicles, obtained from rat skeletal muscle, and related to variations in lactate/H+ transport capacity. Vesicle preparations were made from red and white muscles, mixed muscles, denervated...... muscles, muscles of old rats and rats that had been subjected to high-intensity training, endurance training, repeated exposure to hypoxia, and hypothyroid or hyperthyroid treatments. The lactate/H+ transport capacity of red muscles was greater than that of white muscles, and this difference was...... associated with a higher maximal transport rate (Vmax) in red muscles, whereas the Km was similar in the two muscle types. High-intensity training and hyperthyroidism increased the lactate/H+ transport capacity by enhancing Vmax without affecting Km. Similarly, a reduced transport capacity with old age and...

  5. Appraisal of increased public transport capacity: the case of a new metro line to Nacka, Sweden

    Cats , Oded; West , Jens; ELIASSON, Jonas

    2015-01-01

    One of the most common motivations for public transport investments is increased capacity. However, appraisal methodologies for projects meant to increase capacity are relatively less well developed compared to methodologies for projects aiming to reduce travel times. Each of the consequences of capacity limitations - crowding, risk for denied boarding and unreliable waiting and travel times - can increase the generalized travel costs. The appraisal of capacity improvements requires supply an...

  6. Vision on Scarcity of Transportation. Policy with regard to scarcity of transportation capacity in the electricity grid

    The Dutch Competitive Authority NMa established increasing problems that are related to the (possible future) scarcity in transportation capacity in the electricity grid. This vision document aims to inform market parties about the general vision of NMa in relation to the scarcity issue. This document first addresses the problems related to scarcity in transport capacity in the electricity grid. Next policy developments in this area are discussed and NMa's vision is elaborated and explained

  7. Opportunistic Hybrid Transport Protocol (OHTP) for Cognitive Radio Ad Hoc Sensor Networks.

    Bin Zikria, Yousaf; Nosheen, Summera; Ishmanov, Farruh; Kim, Sung Won

    2015-01-01

    The inefficient assignment of spectrum for different communications purposes, plus technology enhancements and ever-increasing usage of wireless technology is causing spectrum scarcity. To address this issue, one of the proposed solutions in the literature is to access the spectrum dynamically or opportunistically. Therefore, the concept of cognitive radio appeared, which opens up a new research paradigm. There is extensive research on the physical, medium access control and network layers. The impact of the transport layer on the performance of cognitive radio ad hoc sensor networks is still unknown/unexplored. The Internet's de facto transport protocol is not well suited to wireless networks because of its congestion control mechanism. We propose an opportunistic hybrid transport protocol for cognitive radio ad hoc sensor networks. We developed a new congestion control mechanism to differentiate true congestion from interruption loss. After such detection and differentiation, we propose methods to handle them opportunistically. There are several benefits to window- and rate-based protocols. To exploit the benefits of both in order to enhance overall system performance, we propose a hybrid transport protocol. We empirically calculate the optimal threshold value to switch between window- and rate-based mechanisms. We then compare our proposed transport protocol to Transmission Control Protocol (TCP)-friendly rate control, TCP-friendly rate control for cognitive radio, and TCP-friendly window-based control. We ran an extensive set of simulations in Network Simulator 2. The results indicate that the proposed transport protocol performs better than all the others. PMID:26694396

  8. Optimal fares and capacity decisions for crowded public transport systems

    De Palma, André; Lindsey, Robin; Monchambert, Guillaume

    2015-01-01

    International audience There is a large operations research literature on public transit system design. An extensive economic literature has also developed on public transit capacity investments, service frequency, and optimal pricing and subsidy policy. These two branches of literature have made significant advances in understanding public transit systems. However, in contrast to the literature on automobile traffic congestion, most of the studies have employed static models that cannot a...

  9. Least dissipation principle of heat transport potential capacity and its application in heat conduction optimization

    2003-01-01

    In the viewpoint of heat transfer, heat transport potential capacity and its dissipation are defined based on the essence of heat transport phenomenon. Respectively, their physical meanings are the overall heat transfer capabilityand the dissipation rate of the heat transfer capacity. Then the least dissipation principle of heat transport potential capacity is presented to enhance the heat conduction efficiency in the heat conduction optimization. The principle is,for a conduction process with the constant integral of the thermal conductivityover the region, the optimal distribution of thermal conductivity, which corresponds to the highest heat conduction efficiency, is characterized by the least dissipation of heat transport potential capacity. Finally the principle is applied to some cases in heat conduction optimization.

  10. Beyond a complete failure: The impact of partial capacity reductions on public transport network vulnerability

    Cats, O.; Jenelius, E.

    2015-01-01

    Disruptions often result with partial capacity reduction without resulting with a complete breakdown. This study aims to move beyond the analysis of complete failure by investigating the impacts of partial capacity reduction on public transport network performance. We analyse the relation between th

  11. Opportunistic Hybrid Transport Protocol (OHTP for Cognitive Radio Ad Hoc Sensor Networks

    Yousaf Bin Zikria

    2015-12-01

    Full Text Available The inefficient assignment of spectrum for different communications purposes, plus technology enhancements and ever-increasing usage of wireless technology is causing spectrum scarcity. To address this issue, one of the proposed solutions in the literature is to access the spectrum dynamically or opportunistically. Therefore, the concept of cognitive radio appeared, which opens up a new research paradigm. There is extensive research on the physical, medium access control and network layers. The impact of the transport layer on the performance of cognitive radio ad hoc sensor networks is still unknown/unexplored. The Internet’s de facto transport protocol is not well suited to wireless networks because of its congestion control mechanism. We propose an opportunistic hybrid transport protocol for cognitive radio ad hoc sensor networks. We developed a new congestion control mechanism to differentiate true congestion from interruption loss. After such detection and differentiation, we propose methods to handle them opportunistically. There are several benefits to window- and rate-based protocols. To exploit the benefits of both in order to enhance overall system performance, we propose a hybrid transport protocol. We empirically calculate the optimal threshold value to switch between window- and rate-based mechanisms. We then compare our proposed transport protocol to Transmission Control Protocol (TCP-friendly rate control, TCP-friendly rate control for cognitive radio, and TCP-friendly window-based control. We ran an extensive set of simulations in Network Simulator 2. The results indicate that the proposed transport protocol performs better than all the others.

  12. The interplay between gas-fired electricity generation, transportation capacity and regional price volatility

    North America's northeast natural gas delivery system and its capabilities were described with reference to growth trends, excess generation, fuel switching, market drivers, services, and mechanisms for infrastructure development. The grid system in the northeast will be strengthened with the advent of new natural gas supplies from the Sable Offshore Energy Project, coupled with the Hubline and the Dracut expansion. The desire to redeliver incremental Sable supplies to New York City will support new interconnects between pipelines. FERC Order 637 provides more transportation flexibility for a stronger gridded network with more interconnects. It was noted that the mainline capacity in New England is in good shape, but the degree to which the plans are realized depends on the players themselves. Pipeline suppliers are responding to market signals for expansion and services, and competition is strong in the region. Growth trends in the northeast show that new-gas fired generation is constantly being added, but with a slow economy, every plant may not be operating at 100 per cent load factor every day. Older steam boilers with fuel switching capabilities will move down the dispatch curve. If the boilers go off line due to economics, fuel switching will be impacted. With distillate as backup, it can be expected that prices will remain higher for longer periods during high demand. The challenge for regulators will be to ensure reliable power supply and price stability. 2 figs

  13. Measuring the pollutant transport capacity of dissolved organic matter in complex matrixes

    Persson, L.; Alsberg, T.; Odham, G.;

    2003-01-01

    Dissolved organic matter (DOM) facilitated transport in contaminated groundwater was investigated through the measurement of the binding capacity of landfill leachate DOM (Vejen, Denmark) towards two model pollutants (pyrene and phenanthrene). Three different methods for measuring binding capacity...... were used and evaluated, head-space solid-phase micro-extraction (HS-SPME), enhanced solubility (ES) and fluorescence quenching (FQ). It was concluded that for samples with complex matrixes it was possible to measure the net effect of the DOM binding capacity and the salting out effect of the matrix...... binding capacity....

  14. Optimum Repartition of Transport Capacities in the Logistic System using Dynamic Programming

    Gheorghe BĂŞANU

    2011-08-01

    Full Text Available Transportations take an essential role in logistics, interconnecting the majority of processes and operations within logistic system. The efficient use of transportation capacity is a priority whose achievement can diminish logistic costs. This objective is today difficult to achieve due to increasing complexity of transportation monitoring and coordination. This complexity is determined by transportation number and diversity, by the volume and diversity of orders, by increasing the targets to be supplied.Dynamic programming represents a highly useful tool for logistic managers, considering that its specific techniques and methods are oriented toward solving problems related to resource optimum allocation and utilization.The present paper presents briefly a series of theoretical elements of dynamic programming applied in logistics, based on which it is shown a mathematic model to determine the optimum policy for transport capacity repartition for the area attached to a logistic centre, through three distribution centres.

  15. Climate change and changes in sediment transport capacity in the Colorado Plateau, USA

    Milhous, R.T.

    2005-01-01

    Information is presented on changes in the sediment transport capacity of streams of the Colorado Plateau region of the United States. The changes in transport capacity may be due to changes in climate. Changes in the ability of three rivers in the Colorado Plateau to transport sediment were investigated (Paria River at Lees Ferry, Arizona; Sevier River at Hatch, Utah; and Little Colorado at Woodruff, Arizona) using an index to sediment transport potential (or capacity) of the rivers. The index is called a Sediment Transport Capacity Index (STCI). The parameters in the index are calibrated to measured sediment concentrations. Other investigators have postulated that there have been three climate regimes in the Colorado Plateau during the 20th century: 1905-1941, 1942-1977 and 1978-1998. Time series analyses of the STCI showed reasonably clearly that there was a change in the climate about 1941 and a high probability of a change about 1923-1929. The STCI time series for the Sevier River had the expected pattern because the STCI increased in the years following 1997 nearly to the pre-1942 values from lower 1942-1977 values. The Little Colorado River showed a similar pattern, but not nearly to the magnitude suggested by the change in precipitation. The STCI for the Paria River essentially did not change. Changes in sediment transport also are investigated in the lower San Juan River where alterations in the sediment balance of the river may be due to variations in the character of summer precipitation.

  16. Gas Release and Transport Capacity Investment as Instruments to Foster Competition in Gas Markets

    Chaton, Corinne; Gasmi, Farid; Guillerminet, Marie-Laure; Oviedo, Juan Daniel

    2010-01-01

    Motivated by recent policy events experienced by the European natural gas industry, this paper develops a simple model for analyzing the interaction between gas release and capacity investment programs as tools to improve the performance of imperfectly competitive markets. We consider a regional market in which a measure that has an incumbent release part of its gas to a marketer complements a program of investment in transport capacity dedicated to imports by the marketer, at a regulated tra...

  17. Competence and Capacity-Building Requirements in Transport and Logistics Market

    Bazaras Darius; Čižiūnienė Kristina; Palšaitis Ramūnas; Kabashkin Igor

    2016-01-01

    The article analyses theoretical aspects of the qualitative assessment of logistics and transport specialists’ potential, as well as provides research results on competence and capacity-building process in preparation of logistics and transport specialists. The results enabled to identify problematic areas of graduate integration in the labour market and foresee the possible requirements for professional development. In some cases, internal motivation is related to problematic points or negat...

  18. The meaning of different limiters relations for definig public transport routes capacity

    Adam MOLECKI

    2007-01-01

    Full Text Available The mutual affecting of different limiters of capacity is a very important feature, which makes difficult the right appreciation of the transport systems. In most cases, there is no way to use procedures which define relations by correlation coefficients etc. Completely divergent character of limiters induce that only way of effective appreciation is modeling by Monte Carlo simulations.

  19. Optimal spatial transportation networks where link costs are sublinear in link capacity

    Consider designing a transportation network on n vertices in the plane, with traffic demand uniform over all source–destination pairs. Suppose the cost of a link of length l and capacity c scales as lcβ for fixed 0α(β), where α(β) = 1−(β/2) on 0βsγ

  20. Greedy data transportation scheme with hard packet deadlines for wireless ad hoc networks.

    Lee, HyungJune

    2014-01-01

    We present a greedy data transportation scheme with hard packet deadlines in ad hoc sensor networks of stationary nodes and multiple mobile nodes with scheduled trajectory path and arrival time. In the proposed routing strategy, each stationary ad hoc node en route decides whether to relay a shortest-path stationary node toward destination or a passing-by mobile node that will carry closer to destination. We aim to utilize mobile nodes to minimize the total routing cost as far as the selected route can satisfy the end-to-end packet deadline. We evaluate our proposed routing algorithm in terms of routing cost, packet delivery ratio, packet delivery time, and usability of mobile nodes based on network level simulations. Simulation results show that our proposed algorithm fully exploits the remaining time till packet deadline to turn into networking benefits of reducing the overall routing cost and improving packet delivery performance. Also, we demonstrate that the routing scheme guarantees packet delivery with hard deadlines, contributing to QoS improvement in various network services. PMID:25258736

  1. Species Transport Mechanisms Governing Crossover and Capacity Loss in Vanadium Redox Flow Batteries

    Agar, Ertan

    Vanadium redox flow batteries (VRFBs) are an emerging energy storage technology that offers unique advantages for grid-scale energy storage due to their flexible design and decoupled power/energy feature. Despite their popularity, a series of technical challenges hinder their widespread implementation. Among these, capacity loss (i.e., loss of energy storage capability) due to the undesired species crossover across the membrane has been identified as the key issue limiting the longevity of these systems. This issue is primarily governed by the properties of the membrane and can be mitigated by using proper membrane architectures with desired features. Presently, identifying proper membrane architectures for VRFB systems is hampered by the lack of a fundamental understanding of the nature of species transport mechanisms and how they are related to the membrane properties and key operating conditions. This Ph.D. study seeks to address this critical challenge by exploring the fundamental mechanisms responsible for species transport within the membrane. The overall objective of this dissertation study is to establish a fundamental understanding of the multi-ionic transport in VRFB membranes by investigating the ionic transport mechanisms responsible for crossover, and utilize this understanding to reveal the role of membrane properties and operating conditions on the capacity loss. To achieve these goals, a combined experimental and computational study was designed. An experimentally validated, 2-D, transient VRFB model that can track the vanadium crossover and capture the related capacity loss was developed. In addition to the model, several electrochemical techniques were used to characterize different types of membrane and study the effects of various operating conditions on the species crossover. Using these computational and experimental tools, an in-depth understanding of the species transport mechanisms within the membrane and how they are related to membrane

  2. Evaluating sediment transport capacity relationships for use in ephemeral gully erosion models

    Langendoen, E.J.; Wells, R. R.; Ursic, M. E.; Vieira, D. A. N.; Dabney, S.M.

    2015-01-01

    On cropland, ephemeral gully erosion in the USA may contribute up to 40% of the sediment delivered to the edge of the field. Well-tested, physically- and process-based tools for field and watershed scale prediction of gully erosion are lacking due to the fact that the complex nature of migrating headcuts is poorly understood. Understanding sediment transport capacity downstream of migrating headcuts is essential, as sediment deposition often leads to temporary storage that controls downstream...

  3. Contributions of phenolics and added vitamin C to the antioxidant capacity of pomegranate and grape juices: synergism and antagonism among constituents†

    Bolling, Bradley W.; Chen, Ya-Yen; Chen, C-Y Oliver

    2013-01-01

    The aim of this study was to examine the contribution of sugar, organic acid, neutral phenol, and anthocyanin fractions and added ascorbic acid to grape and pomegranate-nectarine juice total phenol, ORAC, FRAP, and DPPH values. Neutral phenol and anthocyanin fractions contributed ≥75% of the total antioxidant capacity (TAC) for both juices. Intrinsic synergy and antagonism among the fractionated constituents occurred inconsistently in each assay. Sugars and organic acids antagonized pomegrana...

  4. Auction design for gas pipeline transportation capacity-The case of Nabucco and its open season

    As a response to the Russian dominance of the EU's natural gas supplies and the EU's increasing gas demands, major gas pipeline projects are currently under way to enhance the EU's energy supply security. Oftentimes to raise financing and to allocate gas transportation capacities, auctions are carried out to allow gas shippers to book transportation rights. In recent years, auctions have emerged as one of the most successful allocation mechanisms in the microeconomic theory. However, different auction designs can lead to different outcomes making the choice of auction design a decisive one, especially for divisible-good auctions. This paper seeks to give a formulation of an optimal auction design for gas pipeline transportation capacity. Specifically three different mechanisms are tested: (i) NPV allocation; (ii) pro rata allocation; and (iii) optimization. In addition, Nabucco is taken as a case study to empirically show results of such auction designs. Results show that a trade-off between revenue optimization and fair allocation can be observed: allocation per optimization is the favorable auction design when revenue maximization is more important than fair allocation. On the other hand, pro rata allocation is the auction design to be chosen when fairness of allocation is considered most central. - Research highlights: → Auction design for gas pipeline transportation capacity. → Empirical market-survey of Nabucco pipeline project auction as input data. → Testing of three different allocation mechanisms: (i) NPV allocation; (ii) pro rata allocation; and (iii) optimization. → Results show a trade-off between revenue optimization and fair allocation. → Allocation per optimization is the favorable auction design when revenue maximization is more important than fair allocation. → On the other hand, pro rata allocation is the auction design to be chosen when fairness of allocation is considered most central.

  5. Structure-Based Engineering of Lithium-Transport Capacity in an Archaeal Sodium-Calcium Exchanger.

    Refaeli, Bosmat; Giladi, Moshe; Hiller, Reuben; Khananshvili, Daniel

    2016-03-29

    Members of the Ca(2+)/cation exchanger superfamily (Ca(2+)/CA) share structural similarities (including highly conserved ion-coordinating residues) while exhibiting differential selectivity for Ca(2+), Na(+), H(+), K(+), and Li(+). The archaeal Na(+)/Ca(2+) exchanger (NCX_Mj) and its mammalian orthologs are highly selective for Na(+), whereas the mitochondrial ortholog (NCLX) can transport either Li(+) or Na(+) in exchange with Ca(2+). Here, structure-based replacement of ion-coordinating residues in NCX_Mj resulted in a capacity for transporting either Na(+) or Li(+), similar to the case for NCLX. This engineered protein may serve as a model for elucidating the mechanisms underlying ion selectivity and ion-coupled alternating access in NCX and similar proteins. PMID:26958982

  6. Competence and Capacity-Building Requirements in Transport and Logistics Market

    Bazaras Darius

    2016-03-01

    Full Text Available The article analyses theoretical aspects of the qualitative assessment of logistics and transport specialists’ potential, as well as provides research results on competence and capacity-building process in preparation of logistics and transport specialists. The results enabled to identify problematic areas of graduate integration in the labour market and foresee the possible requirements for professional development. In some cases, internal motivation is related to problematic points or negative view from the environment, as well as poor understanding of knowledge benefits in the person’s practical life. Training and education is objectively at the meeting point between research, technological and organisational systems. In such conditions the objective of the education on logistics is to offer the customers the best possible service in the field of the transfer of knowledge in harmony with the trend in logistics programme development. The main problems and perspectives of logistics education and training process are discussed in this article.

  7. Underestimation of the Maximal Capacity of the Mitochondrial Electron Transport System in Oligomycin-Treated Cells.

    Ruas, Juliana S; Siqueira-Santos, Edilene S; Amigo, Ignacio; Rodrigues-Silva, Erika; Kowaltowski, Alicia J; Castilho, Roger F

    2016-01-01

    The maximal capacity of the mitochondrial electron transport system (ETS) in intact cells is frequently estimated by promoting protonophore-induced maximal oxygen consumption preceded by inhibition of oxidative phosphorylation by oligomycin. In the present study, human glioma (T98G and U-87MG) and prostate cancer (PC-3) cells were titrated with different concentrations of the protonophore CCCP to induce maximal oxygen consumption rate (OCR) within respirometers in a conventional growth medium. The results demonstrate that the presence of oligomycin or its A-isomer leads to underestimation of maximal ETS capacity. In the presence of oligomycin, the spare respiratory capacity (SRC), i.e., the difference between the maximal and basal cellular OCR, was underestimated by 25 to 45%. The inhibitory effect of oligomycin on SRC was more pronounced in T98G cells and was observed in both suspended and attached cells. Underestimation of SRC also occurred when oxidative phosphorylation was fully inhibited by the ATP synthase inhibitor citreoviridin. Further experiments indicated that oligomycin cannot be replaced by the adenine nucleotide translocase inhibitors bongkrekic acid or carboxyatractyloside because, although these compounds have effects in permeabilized cells, they do not inhibit oxidative phosphorylation in intact cells. We replaced CCCP by FCCP, another potent protonophore and similar results were observed. Lower maximal OCR and SRC values were obtained with the weaker protonophore 2,4-dinitrophenol, and these parameters were not affected by the presence of oligomycin. In permeabilized cells or isolated brain mitochondria incubated with respiratory substrates, only a minor inhibitory effect of oligomycin on CCCP-induced maximal OCR was observed. We conclude that unless a previously validated protocol is employed, maximal ETS capacity in intact cells should be estimated without oligomycin. The inhibitory effect of an ATP synthase blocker on potent protonophore

  8. Underestimation of the Maximal Capacity of the Mitochondrial Electron Transport System in Oligomycin-Treated Cells.

    Juliana S Ruas

    Full Text Available The maximal capacity of the mitochondrial electron transport system (ETS in intact cells is frequently estimated by promoting protonophore-induced maximal oxygen consumption preceded by inhibition of oxidative phosphorylation by oligomycin. In the present study, human glioma (T98G and U-87MG and prostate cancer (PC-3 cells were titrated with different concentrations of the protonophore CCCP to induce maximal oxygen consumption rate (OCR within respirometers in a conventional growth medium. The results demonstrate that the presence of oligomycin or its A-isomer leads to underestimation of maximal ETS capacity. In the presence of oligomycin, the spare respiratory capacity (SRC, i.e., the difference between the maximal and basal cellular OCR, was underestimated by 25 to 45%. The inhibitory effect of oligomycin on SRC was more pronounced in T98G cells and was observed in both suspended and attached cells. Underestimation of SRC also occurred when oxidative phosphorylation was fully inhibited by the ATP synthase inhibitor citreoviridin. Further experiments indicated that oligomycin cannot be replaced by the adenine nucleotide translocase inhibitors bongkrekic acid or carboxyatractyloside because, although these compounds have effects in permeabilized cells, they do not inhibit oxidative phosphorylation in intact cells. We replaced CCCP by FCCP, another potent protonophore and similar results were observed. Lower maximal OCR and SRC values were obtained with the weaker protonophore 2,4-dinitrophenol, and these parameters were not affected by the presence of oligomycin. In permeabilized cells or isolated brain mitochondria incubated with respiratory substrates, only a minor inhibitory effect of oligomycin on CCCP-induced maximal OCR was observed. We conclude that unless a previously validated protocol is employed, maximal ETS capacity in intact cells should be estimated without oligomycin. The inhibitory effect of an ATP synthase blocker on potent

  9. The Use of Artificial Neural Networks to Assess the Capacity of Transport Measures

    Duchaczek Artur

    2015-06-01

    Full Text Available In the area of logistics management both managers and engineers rely primarily on proven computational algorithms, for this reason, it is often difficult to convince them to the use of artificial neural networks in solving decision problems. The paper presents the possibilities of using the FANN library in building of a computer application applied in the area of logistics. The possibilities of the component are presented on the example of applications of artificial neural networks to estimate the capacity of transport vehicles based on their dimensions. The example presented in the work was solved with the use of a multi-network Layered Perceptron. The example depicted not only the possibility of using artificial neural networks for solving poorly structured tasks but also practical application of the TFannNetwork component

  10. SLC2A9 is a high-capacity urate transporter in humans.

    Mark J Caulfield

    2008-10-01

    0.98, 95% confidence interval [CI] 0.9 to 1.05, p > 0.33 by meta-analysis of an SLC2A9 variant in six case-control studies including 11,897 participants. In a separate meta-analysis of four population studies including 11,629 participants we found no association of SLC2A9 with systolic (effect size -0.12 mm Hg, 95% CI -0.68 to 0.43, p = 0.664 or diastolic blood pressure (effect size -0.03 mm Hg, 95% CI -0.39 to 0.31, p = 0.82. CONCLUSIONS: This study provides evidence that SLC2A9 splice variants act as high-capacity urate transporters and is one of the first functional characterisations of findings from genome-wide association scans. We did not find an association of the SLC2A9 gene with blood pressure in this study. Our findings suggest potential pathogenic mechanisms that could offer a new drug target for gout.

  11. Peritoneal transport in CAPD patients with permanent loss of ultrafiltration capacity

    During a 10 year period, 14 out of 227 patients (6.2%) undergoing continuous ambulatory peritoneal dialysis (CAPD) developed permanent loss of ultrafiltration capacity (UFC). The risk of UFC loss increased from 2.6% after one year to 30.9% after six years of treatment. A six hour, single dwell study with glucose 3.86% dialysis fluid was carried out in nine of the UFC loss patients and in 18 CAPD patients with normal UFC. Intraperitoneal dialysate volumes were calculated using 131I-tagged albumin (RISA) as volume marker with a correction applied for its elimination from the peritoneal cavity. The RISA elimination coefficient (KE), which can serve as an estimation of the upper limit of the lymphatic flow, was also calculated. Diffusive mass transport coefficients (KBD) for investigated solutes (glucose, creatinine, urea, potassium, total protein, albumin and beta 2-microglobulin) were calculated during a period of dialysate isovolemia. Two patterns of UFC loss were observed: (a) seven patients had high KBD values for small solutes resulting in rapid uptake of glucose, whereas KBD values for proteins were normal; (b) two patients had normal KBD values but a threefold increase both in the fluid reabsorption rate and KE. We conclude that loss of the osmotic driving force (due to increased diffusive mass transport for small solutes) and increased fluid reabsorption (possibly due to increased lymphatic reabsorption) are the two major causes of permanent loss of UFC in CAPD patients

  12. Vegetative impacts upon bedload transport capacity and channel stability for differing alluvial planforms in the Yellow River source zone

    Li, Zhi Wei; Yu, Guo An; Brierley, Gary; Wang, Zhao Yin

    2016-07-01

    The influence of vegetation upon bedload transport and channel morphodynamics is examined along a channel stability gradient ranging from meandering to anabranching to anabranching-braided to fully braided planform conditions along trunk and tributary reaches of the Upper Yellow River in western China. Although the regional geology and climate are relatively consistent across the study area, there is a distinct gradient in the presence and abundance of riparian vegetation for these reaches atop the Qinghai-Tibet Plateau (elevations in the study area range from 2800 to 3400 m a.s.l.). To date, the influence of vegetative impacts upon channel planform and bedload transport capacity of alluvial reaches of the Upper Yellow River remains unclear because of a lack of hydrological and field data. In this region, the types and pattern of riparian vegetation vary with planform type as follows: trees exert the strongest influence in the anabranching reach, the meandering reach flows through meadow vegetation, the anabranching-braided reach has a grass, herb, and sparse shrub cover, and the braided reach has no riparian vegetation. A non-linear relation between vegetative cover on the valley floor and bedload transport capacity is evident, wherein bedload transport capacity is the highest for the anabranching reach, roughly followed by the anabranching-braided, braided, and meandering reaches. The relationship between the bedload transport capacity of a reach and sediment supply from upstream exerts a significant influence upon channel stability. Bedload transport capacity during the flood season (June-September) in the braided reach is much less than the rate of sediment supply, inducing bed aggradation and dynamic channel adjustments. Rates of channel adjustment are less pronounced for the anabranching-braided and anabranching reaches, while the meandering reach is relatively stable (i.e., this is a passive meandering reach).

  13. Dry matter accumulation in citrus fruit is not limited by transport capacity of the pedicel.

    Garcia-Luis, A; Oliveira, M E M; Bordon, Y; Siqueira, D L; Tominaga, S; Guardiola, J L

    2002-12-01

    mass transfer in the phloem but had no influence on fruit growth. These observations demonstrate that the transport capacity in the phloem of the pedicel does not limit fruit growth and, within the limits of our experiments, an increase in demand by the fruit appeared to be matched by an increase in SMT. The dependence of late xylem formation (after the period of fruitlet abscission) on fruitlet growth was demonstrated in Salustiana orange [Citrus sinensis (L.) Osbeck] by means of controlling fruit growth through the manipulation of leaf area. Fruit growth at this time was more closely related to leaf area than to carbohydrate levels, suggesting that it may be limited by current photosynthesis. PMID:12451031

  14. Developing low-carbon transport policies in Peru with capacity-building for their implementation: Draft Transport NAMA

    Tyler, N. A.; Ramirez, C.

    2012-01-01

    Transport has been identified as one of the biggest sectors that contribute to climate change (23%) due to its energy demand and polluting emissions and therefore one of the sectors that needs to take action to mitigate its impact. A few countries in Latin America (Brazil, Chile, Mexico and Colombia) have started their transport NAMA development and are at different stages in the process. Peru has started this process more recently and this report aims at facilitating the NAMA development and...

  15. Effect of dietary creatine monohydrate supplementation on muscle lipid peroxidation and antioxidant capacity of transported broilers in summer.

    Wang, X F; Zhu, X D; Li, Y J; Liu, Y; Li, J L; Gao, F; Zhou, G H; Zhang, L

    2015-11-01

    This experiment was to evaluate the effect of dietary supplementation with creatine monohydrate (CMH) during the finishing period on the muscle lipid peroxidation and antioxidant capacity of broilers that experienced transport stress in summer. A total of 320 male Arbor Acres broilers (28 d in age) were randomly allotted to 3 dietary treatments including a basal control diet without additional CMH (160 birds), or with 600 (80 birds) or 1,200 mg/kg (80 birds) CMH for 14 d. On the morning of d 42, after an 8-h fast, the birds fed the basal diets were divided into 2 equal groups, and all birds in the 4 groups of 80 birds were transported according to the following protocols: 1) a 0.75-h transport of birds on basal diets (as a lower-stress control group), 2) a 3-h transport of birds on basal diets, 3) a 3-h transport of birds on 600 or 4) 1,200 mg/kg CMH supplementation diets. The results showed that the 3-h transport decreased the concentration of creatine (Cr) in both the pectoralis major (PM) and the tibialis anterior (TA) muscles, increased the concentration of phosphocreatine (PCr) and PCr/Cr ratio in PM muscle, and elevated the concentrations of thiobarbituric acid-reactive substances and the activities of total superoxide dismutase and glutathione peroxidase in both the PM and TA muscles of birds (P protein and heat shock protein 70 in both the PM and TA muscles, as well as avian peroxisome proliferator-activated receptor γ coactivator-1α in the TA muscle (P 0.05). These results indicate that dietary CMH supplementation does not provide any significant protection via directly scavenging free radicals or increased antioxidant capacity of transported broilers. PMID:26371332

  16. Molecular imaging of acetylcholine vesicular transporter (VAChT) in demented patients with Alzheimer's disease (AD) by IBVM-SPECT

    Alzheimer's disease (A.D.) is characterized by a premature decline of cholinergic neurons. The 5-I.B.V.M. is an analogue of the Vesamicol that binds to the presynaptic vesicular acetylcholine transporter (VAChT). The exploration of this target should be useful to make an early diagnosis of A.D.. Our first aim was to propose a method of non invasive VAChT quantification according to 5-I.B.V.M. kinetic. 5-I.B.V.M. was injected to four A.D. patients (age = 77 ± 3.9 years and M.M.S.E. = 24.5 ± 1.02) were included in this methodological study. The single-photon emission computed tomography (SPECT) images were obtained at five, 20, 35 and 50 minutes, at then at three, five and 22 hours after intravenous injection of 5-I.B.V.M. (185 MBq). The time activity curves were obtained after SPECT images co registration on a MRI masque. Specific volume of interest (S.P.E. SPEcific) were manually drawn on striatum, pons, thalamus and para-hippocampic gyrus including hippocampus; reference volumes of interest (R.E.F. = REFerence) were drawn on frontal and occipital cerebral cortex. On the basis of uptake kinetic, two modeling approaches were considered: transient equilibrium model for reversible ligand (binding potential (B.P.) (S.P.E. - R.E.F.)/R.E.F.) and Patlak graphical analysis for irreversible tracers (slope given by Ki/DVref where Ki is the influx constant and DVref is the distribution volume of the reference region). We observed an inflection or a steady state of the activity curves in the different regions studied between 250 and 1400 minutes, what seems to confirm that the tracer is little reversible. B.P. values obtained at 21 hours with occipital areas as reference and Ki/DVref values were respectively 4.62 ± 0.42 and 0.07 ± 0.01. The S.P.E. classification according to B.P. and Ki/DVref values were similar to the classification according to the compartmental analysis (Kuhl 1994). The transient equilibrium model with late acquisition seems the more suitable because I

  17. An assessment of the added value from data assimilation on modelled Nordic Seas hydrography and ocean transports

    Lien, Vidar S.; Hjøllo, Solfrid S.; Skogen, Morten D.; Svendsen, Einar; Wehde, Henning; Bertino, Laurent; Counillon, Francois; Chevallier, Matthieu; Garric, Gilles

    2016-03-01

    The Nordic Seas is a hotspot both in terms of climate related processes, such as Atlantic-Arctic heat exchange, and natural marine resources. A sustainable management of the marine resources within the Nordic Seas, including the co-existence between fisheries and petroleum industries, requires detailed information on the state of the ocean within an operational framework and beyond what is obtainable from observations only. Numerical ocean models applying data assimilation techniques are utilized to address this need. Subsequently, comprehensive comparisons between model results and observations are required in order to assess the model performance. Here, we apply a set of objective statistics to quantitatively assess the added value of data assimilation in numerical ocean models that are currently used operationally. The results indicate that the inclusion of data assimilation improves the model performance both in terms of hydrographic properties and volume and heat transports. Furthermore, we find that increasing the resolution towards eddy resolving resolution performs similarly to coarser resolution models applying data assimilation in shelf areas.

  18. Modeling Np and Pu transport with a surface complexation model and spatially variant sorption capacities: Implications for reactive transport modeling and performance assessments of nuclear waste disposal sites

    Glynn, P.D.

    2003-01-01

    One-dimensional (1D) geochemical transport modeling is used to demonstrate the effects of speciation and sorption reactions on the ground-water transport of Np and Pu, two redox-sensitive elements. Earlier 1D simulations (Reardon, 1981) considered the kinetically limited dissolution of calcite and its effect on ion-exchange reactions (involving 90Sr, Ca, Na, Mg and K), and documented the spatial variation of a 90Sr partition coefficient under both transient and steady-state chemical conditions. In contrast, the simulations presented here assume local equilibrium for all reactions, and consider sorption on constant potential, rather than constant charge, surfaces. Reardon's (1981) seminal findings on the spatial and temporal variability of partitioning (of 90Sr) are reexamined and found partially caused by his assumption of a kinetically limited reaction. In the present work, sorption is assumed the predominant retardation process controlling Pu and Np transport, and is simulated using a diffuse-double-layer-surface-complexation (DDLSC) model. Transport simulations consider the infiltration of Np- and Pu-contaminated waters into an initially uncontaminated environment, followed by the cleanup of the resultant contamination with uncontaminated water. Simulations are conducted using different spatial distributions of sorption capacities (with the same total potential sorption capacity, but with different variances and spatial correlation structures). Results obtained differ markedly from those that would be obtained in transport simulations using constant Kd, Langmuir or Freundlich sorption models. When possible, simulation results (breakthrough curves) are fitted to a constant K d advection-dispersion transport model and compared. Functional differences often are great enough that they prevent a meaningful fit of the simulation results with a constant K d (or even a Langmuir or Freundlich) model, even in the case of Np, a weakly sorbed radionuclide under the

  19. Certification challenges in the development of an innovative high payload capacity spent fuel transportation cask

    The design approach and certification strategy used in the development of an innovative transportation cask for legal weight truck shipments of spent nuclear fuel is presented. The proposed approach represents a significant departure from conventional cask designs in that it uses titanium alloy, a material with a high strength-to-weight ratio which has no precedent in transportation cask certification. The significant increase in payload obtainable with the proposed approach, and the associated benefits such as reduced life cycle costs, lower personnel exposure, and lower transportation accident risks are discussed. 8 refs., 3 figs., 1 tab

  20. Does recombinant human Epo increase exercise capacity by means other than augmenting oxygen transport?

    Lundby, C; Robach, P; Boushel, R;

    2008-01-01

    This study was performed to test the hypothesis that administration of recombinant human erythropoietin (rHuEpo) in humans increases maximal oxygen consumption by augmenting the maximal oxygen carrying capacity of blood. Systemic and leg oxygen delivery and oxygen uptake were studied during...

  1. Calibration of the 2D Hydrodynamic Model Floodos and Implications of Distributed Friction on Sediment Transport Capacity

    Croissant, T.; Lague, D.; Davy, P.

    2014-12-01

    Numerical models of floodplain dynamics often use a simplified 1D description of flow hydraulics and sediment transport that cannot fully account for differential friction between vegetated banks and low friction in the main channel. Key parameters of such models are the friction coefficient and the description of the channel bathymetry which strongly influence predicted water depth and velocity, and therefore sediment transport capacity. In this study, we use a newly developed 2D hydrodynamic model, Floodos, whose efficiency is a major advantage for exploring channel morphodynamics from a flood event to millennial time scales. We evaluate the quality of Floodos predictions in the Whataroa river, New Zealand and assess the effect of a spatially distributed friction coefficient (SDFC) on long term sediment transport. Predictions from the model are compared to water depth data from a gauging station located on the Whataroa River in Southern Alps, New Zealand. The Digital Elevation Model (DEM) of the 2.5 km long studied reach is derived from a 2010 LiDAR acquisition with 2 m resolution and an interpolated bathymetry. The several large floods experienced by this river during 2010 allow us to access water depth for a wide range of possible river discharges and to retrieve the scaling between these two parameters. The high resolution DEM used has a non-negligible part of submerged bathymetry that airborne LiDAR was not able to capture. Bathymetry can be reconstructed by interpolation methods that introduce several uncertainties concerning water depth predictions. We address these uncertainties inherent to the interpolation using a simplified channel with a geometry (slope and width) similar to the Whataroa river. We then explore the effect of a SDFC on velocity pattern, water depth and sediment transport capacity and discuss its relevance on long term predictions of sediment transport and channel morphodynamics.

  2. MX8: the next generation high capacity system for land transport of Mox fuel

    In the near future, MOX fuel design is adapted in order to comply with the basic requirements of the utility in view to obtain an equivalence with UO2 fuels. An increasing number of reactors is going to be loaded with MOX: up to 28 at the end of the century. It was decide at the end of 1996 to develop a new transport system taking into account the evolutions, and to reduce the number of transports. The new generation of packaging for MOX fuel is the M.X type packaging. (N.C.)

  3. Determination of serum iron and of the transport capacity of iron by transferrin

    Three methods were standardized in order to determine the iron level in serum, the total iron binding capacity of transferrin and the iron binding capacity of free transferrin. The first of them, appropriate to estimate iron and total transferrin level, is based on the development of color as a consequence of iron binding to bathophenanthrolin (BATO); the second, used for the same purposes, employs atomic absorption spectrophotometry (AA); the third, used to estimate free transferrin, is a radioassay (RE). It was known that the methods employing atomic absorption espectrophotometry and radioassay are precise and especific, while the use of bathophenanthrolin constantly provides differing results. This was the reason why statistic analysis of the results showed significant differences between the first method (BATO) and the remaining two (RE and AA). Nevertheless, the fluctuation of results observed with the use of bathophenanthrolin is small (less than 10%), the method is easy to perform and it is not dispendious concerning reagents as well as equipament. Therefore it was concluded that the BATO method is very safe when used for diagnosis of iron deficiency or excess of storage, even of low magnitude. (Author)

  4. Physics of transportation: Towards optimal capacity using the multilayer network framework

    Du, Wen-Bo; Zhou, Xing-Lian; Jusup, Marko; Wang, Zhen

    2016-01-01

    Because of the critical role of transportation in modern times, one of the most successful application areas of statistical physics of complex networks is the study of traffic dynamics. However, the vast majority of works treat transportation networks as an isolated system, which is inconsistent with the fact that many complex networks are interrelated in a nontrivial way. To mimic a realistic scenario, we use the framework of multilayer networks to construct a two-layered traffic model, whereby the upper layer provides higher transport speed than the lower layer. Moreover, passengers are guided to travel along the path of minimal travelling time and with the additional cost they can transfer from one layer to another to avoid congestion and/or reach the final destination faster. By means of numerical simulations, we show that a degree distribution-based strategy, although facilitating the cooperation between both layers, can be further improved by enhancing the critical generating rate of passengers using a particle swarm optimisation (PSO) algorithm. If initialised with the prior knowledge from the degree distribution-based strategy, the PSO algorithm converges considerably faster. Our work exemplifies how statistical physics of complex networks can positively affect daily life. PMID:26791580

  5. Enhanced Glucose Transport, but not Phosphorylation Capacity, Ameliorates Lipopolysaccharide-Induced Impairments in Insulin-Stimulated Muscle Glucose Uptake.

    Otero, Yolanda F; Mulligan, Kimberly X; Barnes, Tammy M; Ford, Eric A; Malabanan, Carlo M; Zong, Haihong; Pessin, Jeffrey E; Wasserman, David H; McGuinness, Owen P

    2016-06-01

    Lipopolysaccharide (LPS) is known to impair insulin-stimulated muscle glucose uptake (MGU). We determined if increased glucose transport (GLUT4) or phosphorylation capacity (hexokinase II; HKII) could overcome the impairment in MGU. We used mice that overexpressed GLUT4 (GLUT4) or HKII (HK) in skeletal muscle. Studies were performed in conscious, chronically catheterized (carotid artery and jugular vein) mice. Mice received an intravenous bolus of either LPS (10 μg/g body weight) or vehicle (VEH). After 5 h, a hyperinsulinemic-euglycemic clamp was performed. As MGU is also dependent on cardiovascular function that is negatively affected by LPS, cardiac function was assessed using echocardiography. LPS decreased whole body glucose disposal and MGU in wild-type (WT) and HK mice. In contrast, the decrease was attenuated in GLUT4 mice. Although membrane-associated GLUT4 was increased in VEH-treated GLUT4 mice, LPS impaired membrane-associated GLUT4 in GLUT4 mice to the same level as LPS-treated WT mice. This suggested that overexpression of GLUT4 had further benefits beyond preserving transport activity. In fact, GLUT4 overexpression attenuated the LPS-induced decrease in cardiac function. The maintenance of MGU in GLUT4 mice following LPS was accompanied by sustained anaerobic glycolytic flux as suggested by increased muscle Pdk4 expression, and elevated lactate availability. Thus, enhanced glucose transport, but not phosphorylation capacity, ameliorates LPS-induced impairments in MGU. This benefit is mediated by long-term adaptations to the overexpression of GLUT4 that sustain muscle anaerobic glycolytic flux and cardiac function in response to LPS. PMID:26682946

  6. The Effects of Projected Future Demand Including Very Light Jet Air-Taxi Operations on U.S. National Airspace System Delays as a Function of Next Generation Air Transportation System Airspace Capacity

    Smith, Jerry; Viken, Jeff; Dollyhigh, Samuel; Trani, Antonio; Baik, Hojong; Hinze, Nicholas; Ashiabor, Senanu

    2007-01-01

    This paper presents the results from a study which investigates the potential effects of the growth in air traffic demand including projected Very Light Jet (VLJ) air-taxi operations adding to delays experienced by commercial passenger air transportation in the year 2025. The geographic region studied is the contiguous United States (U.S.) of America, although international air traffic to and from the U.S. is included. The main focus of this paper is to determine how much air traffic growth, including VLJ air-taxi operations will add to enroute airspace congestion and determine what additional airspace capacity will be needed to accommodate the expected demand. Terminal airspace is not modeled and increased airport capacity is assumed.

  7. Interactive effects of hypoxia, carbon monoxide and acute lung injury on oxygen transport and aerobic capacity.

    Crocker, George H; Jones, James H

    2016-05-01

    This study determined how breathing hypoxic gas, reducing circulatory capacitance for O2 by breathing CO, and impairing pulmonary gas exchange by acutely injuring the lungs interact to limit cardiopulmonary O2 delivery, O2 extraction and maximal aerobic capacity (VO2max). Five goats ran on a treadmill at VO2max following oleic-acid induced acute lung injury that impaired pulmonary gas exchange, after partial recovery or with no acute lung injury. Goats breathed normoxic or hypoxic inspired gas fractions (FIO2 0.21 or 0.12) with and without small amounts of CO to maintain carboxyhemoglobin fractions (FHbCO) of 0.02 or 0.30. With the exception of elevated FHbCO with acute lung injury (P=0.08), all combinations of hypoxia, elevated FHbCO and acute lung injury attenuated the reduction in VO2max by 15-27% compared to the sum of each treatment's individual reduction in VO2max when administered separately. Simultaneous administration of two treatments attenuated the reduction in VO2max by attenuating the decrease in cardiopulmonary O2 delivery, not synergistically increasing O2 extraction. PMID:26845454

  8. You've Got to Move It, Move It--Adding Logistics and Distribution to the Transportation Curriculum

    Roads, David R.

    2012-01-01

    Long gone are the days when the study of the internal combustion engine was the core of the transportation curriculum offered in most middle schools and high schools. To be competitive and successful, today's students need a more global understanding of transportation, distribution, and logistics systems. In response to this shift to include…

  9. Increasing the process capacity of a knowledge intensive process through the use of process reengineering and knowledge-value added methodologies

    Baxter, Joseph L.; Campbell, Errol A.

    2003-01-01

    Approved for public release; distribution is unlimited. In the increasingly dynamic environment of information technology, it has become imperative that organizations continue to seek ways to effectively capture and measure knowledge in order to survive. With the emergence of a global economy and information networks, the knowledge creating capacity within organizations has grown tremendously. As a result, organizations are now shifting their focus to management of the knowledge used in ex...

  10. Variant at serotonin transporter gene predicts increased imitation in toddlers: relevance to the human capacity for cumulative culture.

    Schroeder, Kari Britt; Asherson, Philip; Blake, Peter R; Fenstermacher, Susan K; Saudino, Kimberly J

    2016-04-01

    Cumulative culture ostensibly arises from a set of sociocognitive processes which includes high-fidelity production imitation, prosociality and group identification. The latter processes are facilitated by unconscious imitation or social mimicry. The proximate mechanisms of individual variation in imitation may thus shed light on the evolutionary history of the human capacity for cumulative culture. In humans, a genetic component to variation in the propensity for imitation is likely. A functional length polymorphism in the serotonin transporter gene, the short allele at 5HTTLPR, is associated with heightened responsiveness to the social environment as well as anatomical and activational differences in the brain's imitation circuity. Here, we evaluate whether this polymorphism contributes to variation in production imitation and social mimicry. Toddlers with the short allele at 5HTTLPR exhibit increased social mimicry and increased fidelity of demonstrated novel object manipulations. Thus, the short allele is associated with two forms of imitation that may underlie the human capacity for cumulative culture. The short allele spread relatively recently, possibly due to selection, and its frequency varies dramatically on a global scale. Diverse observations can be unified via conceptualization of 5HTTLPR as influencing the propensity to experience others' emotions, actions and sensations, potentially through the mirror mechanism. PMID:27072408

  11. Epidermal growth factor decreases PEPT2 transport capacity and expression in the rat kidney proximal tubule cell line SKPT0193 cl.2

    Bravo, Silvina A; Nielsen, Carsten Uhd; Amstrup, Jan; Frokjaer, Sven; Brodin, Birger

    2004-01-01

    suggests that this might be disadvantageous when studying PEPT2-mediated transport phenomena. These findings demonstrate for the first time EGF-mediated regulation of PEPT2 expression in a kidney cell line. The relevance for kidney regulation of peptide transport activity in physiological and......The renal peptide transporter PEPT2 plays an important role in absorption of di- and tripetides in the proximal tubule; however, knowledge of regulation of PEPT2 by growth factors and hormones is limited. In the present study, we examined the effects of epidermal growth factor (EGF) on PEPT2...... transport capacity and expression in the rat proximal tubule cell line SKPT0193 cl.2 (SKPT), which expresses rat PEPT2 (rPEPT2) in the apical membrane. Treatment of SKPT cells with EGF during cell culture growth caused a dose-dependent decrease in rPEPT2 transport capacity and expression, as determined by...

  12. 17 CFR 240.17Ad-19 - Requirements for cancellation, processing, storage, transportation, and destruction or other...

    2010-04-01

    ... Securities Exchange Act of 1934 Supervised Investment Bank Holding Company Rules § 240.17Ad-19 Requirements... cancellation means the process in which a securities certificate: (i) Is physically marked to clearly indicate... transfer agent. (2) The term cancelled certificate facility means any location where...

  13. Illustration of the Alliances platform chemistry/transport coupling capacities through the simulation of a cement/clay interaction

    Safety studies in a subsurface environment and in an underground waste disposal necessitate numerical tools for reactive transport modelling. In these systems, hydrogeological and chemical processes are closely related and their interdependence must be analysed to study migration of species. We will illustrate here the capacities of the Alliances tool to simulate such a phenomenology by studying the evolution of a clay/cement interface over time. The goal being defined, the two main employed software to build up a multidimensional tool have been chosen, namely PhreeqC and Chess for chemistry. A common model has been developed whose aim is to allow models comparison while switching between the chemistry tools. For transport, Castem and Mt3d-99 have been introduced with the same philosophy of structure. It is worth noting that other tools could be introduced, the only requirement being to satisfy the specific data-model and building up the appropriate methods. Qualification cases have been built up to define the platform application field. It has been defined with one and two dimensional cases enabling a comparison with analytic solutions or an intercomparison with other reactive transport codes. To illustrate this in the chemistry coupling field, we focus on a clay cement interface with an ion exchange linked to the Ca-montmorillonite. This case has been defined at ANDRA to be used as a reference test case for chemistry coupling validation. Results show a good agreement between platform results and whose of PhreeqC with its own internal coupling. The clay/cement interface is reproduced with the same accuracy

  14. Accessibility appraisal of land-use/transport policy strategies: More than just adding up travel-time savings

    Geurs, Karst; Zondag, Barry; Jong, de Gerard; Bok, de Michiel

    2010-01-01

    We examine the accessibility benefits associated with some land-use policy strategies for the Netherlands that anticipate on expected climate change. A disaggregate logsum accessibility measure using the Dutch national land-use/transport interaction model TIGRIS XL is used to compute changes in cons

  15. Effects of temperature, pressure and pure copper added to source material on the CuGaTe2 deposition using close spaced vapor transport technique

    The quality of CuGaTe2 (CGT) thin films elaborated by close spaced vapor transport technique has been studied as a function of the source temperature (TS), iodine pressure (PI2) and the amount (XCu) of pure copper added to the stoichiometric starting material. A thermodynamic model was developed for the Cu–Ga–Te–I system to describe the CGT deposition. The model predicts the solid phase composition with possible impurities for the operating conditions previously mentioned. The conditions of stoichiometric and near-stoichiometric deposition were determined. The value of TS must range from 450 to 550 °C for PI2 varying between 0.2 and 7 kPa. Adding an amount up to 10% of pure copper to the starting material improves the quality of the deposit layers and lowers the operating interval temperature to 325–550 °C. These optimal conditions were tested experimentally at 480 °C and 500 °C. The X-ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy have proved that the addition of pure copper to the stoichiometric source material can be considered as a supplementary operating parameter to improve the quality of CGT thin films. - Highlights: • The stoichiometric CuGaTe2 (CGT) has been deposited by close spaced vapor transport. • The Cu–Ga–Te–I system has been studied theoretically by minimizing the Gibbs energy. • The quality of thin films has been improved by pure copper added to the source CGT. • The temperature, pressure and the amount of copper added to grow CGT are determined. • The thermodynamic predictions are in good agreement with experimental results

  16. Effects of temperature, pressure and pure copper added to source material on the CuGaTe{sub 2} deposition using close spaced vapor transport technique

    Abounachit, O. [LP2M2E, Faculté des Sciences et Techniques, Université Cadi Ayyad, Gueliz, BP 549 , Marrakech, Maroc (Morocco); Chehouani, H., E-mail: chehouani@hotmail.fr [LP2M2E, Faculté des Sciences et Techniques, Université Cadi Ayyad, Gueliz, BP 549 , Marrakech, Maroc (Morocco); Djessas, K. [CNRS-PROMES Tecnosud, Rambla de la Thermodynamique, 66100 Perpignan (France)

    2013-07-01

    The quality of CuGaTe{sub 2} (CGT) thin films elaborated by close spaced vapor transport technique has been studied as a function of the source temperature (T{sub S}), iodine pressure (P{sub I2}) and the amount (X{sub Cu}) of pure copper added to the stoichiometric starting material. A thermodynamic model was developed for the Cu–Ga–Te–I system to describe the CGT deposition. The model predicts the solid phase composition with possible impurities for the operating conditions previously mentioned. The conditions of stoichiometric and near-stoichiometric deposition were determined. The value of T{sub S} must range from 450 to 550 °C for P{sub I2} varying between 0.2 and 7 kPa. Adding an amount up to 10% of pure copper to the starting material improves the quality of the deposit layers and lowers the operating interval temperature to 325–550 °C. These optimal conditions were tested experimentally at 480 °C and 500 °C. The X-ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy have proved that the addition of pure copper to the stoichiometric source material can be considered as a supplementary operating parameter to improve the quality of CGT thin films. - Highlights: • The stoichiometric CuGaTe{sub 2} (CGT) has been deposited by close spaced vapor transport. • The Cu–Ga–Te–I system has been studied theoretically by minimizing the Gibbs energy. • The quality of thin films has been improved by pure copper added to the source CGT. • The temperature, pressure and the amount of copper added to grow CGT are determined. • The thermodynamic predictions are in good agreement with experimental results.

  17. Road transport emissions and capacity of forests in the region of Athens for sequestring these emissions: carbon flow before and after forest fires

    Petros Chatzimpiros; Natalia Roumelioti; Anna Zamba; Kimon Hadjibiros

    2016-01-01

    One important component of the urban contribution to carbon dioxide atmospheric emissions is road transport. Carbon dioxide (CO2) emissions from urban road transport in the centre of Athens recorded over a period of five years (2000–2005) are compared with the carbon sequestration capacity of regional forests, prior to and after the devastating forest fires in Attica in 2007 and 2009, which is the administrative region of Athens. The comparison of carbon flow reveals two complementary aspects...

  18. Determination of the presence of antioxidants deriving from sage and oregano extracts added to animal fat by means of assessment of the radical scavenging capacity by photochemiluminescence analysis.

    Vichi, S; Zitterl-Eglseer, K; Jugl, M; Franz, C

    2001-04-01

    Herbs and their extracts with antioxidant capacity could be used directly as stabilisers of fat and indirectly as feed additives, in order to improve quality and shelf-life of meat and fat-containing food. In this work a sensitive analytical method is proposed for determination of the antioxidant activity measured by photochemiluminescence (PCL) in lard stabilised with extracts of sage (Salvia officinalis L.) or oreganum (Origanum vulgare L.). A prior step of purification of fat samples is required, in order to separate and concentrate the phenolics from lipidic substances. The method was validated by determination of recovery rate and repeatability. In addition fat samples originating from pigs fed with feed additives of Salviae folium or Origani herba were analysed to investigate the supposed antioxidative effects, that could increase the shelf-life of meat products. In contrast with lard mixed with extracts of sage or oregano, back fat samples originating from pigs fed with feed additives of the same herbs didn't show a higher antioxidant activity than the control group. On the one hand it seems possible to keep perishable fat-containing food longer by an addition of an extract of sage or oregano due to their antioxidative properties, on the other hand administration of feed additives of dried herbs to pigs had no effect on quality and shelf-life of fat obtained from these animals. PMID:11379280

  19. Enhancing the Efficiency and Charge Transport Characteristics of Dye-Sensitized Solar Cells by Adding Graphene Nanosheets to TiO2 Working Electrodes

    In this study, TiO2-GN nanocomposite working electrodes were fabricated by adding graphene nanosheets (GNs) to TiO2 thin-film working electrodes. The influence of the thickness of the TiO2 thin-film working electrodes on the efficiency and charge transport characteristics of the corresponding dye-sensitized solar cells (DSSCs) was investigated. A GN solution was spin-coated onto the TiO2 thin films, which were then sintered at 100 °C in order to fabricate TiO2-GN working electrodes. The characteristics of various working electrodes were analyzed via scanning electron microscopy, atomic force microscopy, surface profilometry, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and Raman spectroscopy. Moreover, the DSSCs fabricated from these working electrodes were characterized via current density-voltage, incident photo-to-current conversion efficiency, electrochemical impedance spectroscopy, intensity-modulated photocurrent spectroscopy, and intensity-modulated photovoltage spectroscopy measurements. The results indicate that adding GNs to TiO2 thin films can enhance the electron transport rate and charge collection efficiency in TiO2-GN working electrodes, and thereby increase the power conversion efficiency of DSSCs. As such, DSSCs containing the TiO2-GN working electrodes exhibited an efficiency of 8.07%, which is 24.3% higher than that (6.49%) of the DSSCs containing conventional TiO2 working electrodes

  20. Electrostatic protocol treatment lens. The purpose of this device is to transport Antiprotons from the new ELENA storage beam to all AD experiments. The electrostatic device was successfully tested in ASACUSA two weeks ago.

    Maximilien Brice

    2012-01-01

    Electrostatic protocol treatment lens. The purpose of this device is to transport Antiprotons from the new ELENA storage beam to all AD experiments. The electrostatic device was successfully tested in ASACUSA two weeks ago.

  1. On interaction between MAC and transport layers for media streaming in 802.11 ad hoc networks

    Nahm, Kitae; Helmy, Ahmed; Kuo, C.-C. Jay

    2004-10-01

    We examine the validity of TCP-friendliness and the utility of equation-based congestion control as a mean for the media streaming service in 802.11 multi-hop networks. Our investigation is motivated by the recent findings of the bandwidth-delay product of 802.11 multi-hop networks via intensive computer simulations. We show that TCP behavior in 802.11 multi-hop networks is generally inefficient and unstable because the standard TCP is too aggressive considering the low bandwidth-delay product of 802.11 networks. We introduce the concept of the `fractional window' mechanism (which resembles the stop-and-go protocol) for TCP, and show that the modified TCP is more stable and efficient while outperforming the legacy TCP in 802.11-based ad hoc networks. Finally, we show that many of the typical problems of TCP protocol (performance, network fairness, and TCP-friendliness) in 802.11 networks can be solved simply by increasing the bandwidth-delay product of 802.11 networks without any TCP modification. Based on this observation, we conclude that the assumption of the ideal steady-state TCP behavior is generally invalid in 802.11 multi-hop networking environment, and that congestion control based on TCP-friendly equation can hardly provide TCP-fair throughput and smoothness in 802.11 multi-hop networking environment.

  2. A generalized mathematical model to understand the capacity fading in lithium ion batteries - Effects of solvent and lithium transport

    Abhishek Deshpande; Saksham Phul; Balaji Krishnamurthy

    2015-01-01

    A general mathematical model to study capacity fading in lithium ion batteries is developed. The model assumes that the formation of the Solid Electrolyte interphase(SEI) layer is the primary reason behind the capacity fading in lithium ion batteries. Previous models have assumed that either the solvent or the lithium plays a key role in the film formation reaction which drives the capacity fading in lithium ion batteries. The current model postulates that the solvent species and lithium ions...

  3. Hairy AdS Solitons

    Anabalon, Andres; Choque, David

    2016-01-01

    We construct exact hairy AdS soliton solutions in Einstein-dilaton gravity theory. We discuss the role of these solutions for the existence of first order phase transitions for planar hairy black holes within these theories.

  4. Advanced computer technology - An aspect of the Terminal Configured Vehicle program. [air transportation capacity, productivity, all-weather reliability and noise reduction improvements

    Berkstresser, B. K.

    1975-01-01

    NASA is conducting a Terminal Configured Vehicle program to provide improvements in the air transportation system such as increased system capacity and productivity, increased all-weather reliability, and reduced noise. A typical jet transport has been equipped with highly flexible digital display and automatic control equipment to study operational techniques for conventional takeoff and landing aircraft. The present airborne computer capability of this aircraft employs a multiple computer simple redundancy concept. The next step is to proceed from this concept to a reconfigurable computer system which can degrade gracefully in the event of a failure, adjust critical computations to remaining capacity, and reorder itself, in the case of transients, to the highest order of redundancy and reliability.

  5. A Generalized Mathematical model to understand the capacity fading in lithium ion batteries-Effects of solvent and lithium transport

    Abhishek Deshpande

    2015-12-01

    Full Text Available A general mathematical model to study capacity fading in lithium ion batteries is developed. The model assumes that the formation of the Solid Electrolyte interphase(SEI layer is the primary reason behind the capacity fading in lithium ion batteries. Previous models have assumed that either the solvent or the lithium plays a key role in the film formation reaction which drives the capacity fading in lithium ion batteries. The current model postulates that the solvent species and lithium ions could play a limiting role in the capacity fade in a lithium ion battery. The model studies the concentration profiles of the solvent species and lithium ions at the electrode/film interphase as a function of diffusion and migration parameters. Model predictions are found to fit experimental data very well.

  6. Improving the design of higher-capacity railway tank cars for hazardous materials transport: optimizing the trade-off between weight and safety.

    Barkan, Christopher P L

    2008-12-15

    As with many aspects of modern industrial society, decision-makers face trade-offs in considering hazardous materials transportation equipment and practices. Tank cars used for transport of hazardous materials can be made more resistant to damage in accidents through use of a thicker steel tank and other protective features. However, the additional weight of these features reduces the car's capacity and thus its efficiency as a transportation vehicle. In this paper the problem of tank car safety versus weight is developed as a multi-attribute decision problem. North American railroads recently developed specifications for higher capacity tank cars for transportation of hazardous materials including enhanced safety design features. A group of tank car safety design features or "risk reduction options" (RROs) were analyzed with regard to their effect on the conditional probability of release in an accident, and their incremental effect on tank car weight. All possible combinations of these RROs were then analyzed in terms of the reduced release probability per unit of weight increase and the Pareto optimal set of options identified. This set included the combinations of RROs that provided the greatest improvement in safety with the least amount of additional weight for any desired level of tank car weight increase. The analysis was conducted for both non-insulated and insulated tank cars and used two objective functions, minimization of conditional probability of release, and minimization of expected quantity lost, given that a car was derailed in an accident. Sensitivity analyses of the effect of tank car size and use of different objective functions were conducted and the optimality results were found to be robust. The results of this analysis were used by the Association of American Railroads Tank Car Committee to develop new specifications for higher capacity non-insulated and insulated, non-pressure tank cars resulting in an estimated 32% and 24% respective

  7. Improving the design of higher-capacity railway tank cars for hazardous materials transport: Optimizing the trade-off between weight and safety

    As with many aspects of modern industrial society, decision-makers face trade-offs in considering hazardous materials transportation equipment and practices. Tank cars used for transport of hazardous materials can be made more resistant to damage in accidents through use of a thicker steel tank and other protective features. However, the additional weight of these features reduces the car's capacity and thus its efficiency as a transportation vehicle. In this paper the problem of tank car safety versus weight is developed as a multi-attribute decision problem. North American railroads recently developed specifications for higher capacity tank cars for transportation of hazardous materials including enhanced safety design features. A group of tank car safety design features or 'risk reduction options' (RROs) were analyzed with regard to their effect on the conditional probability of release in an accident, and their incremental effect on tank car weight. All possible combinations of these RROs were then analyzed in terms of the reduced release probability per unit of weight increase and the Pareto optimal set of options identified. This set included the combinations of RROs that provided the greatest improvement in safety with the least amount of additional weight for any desired level of tank car weight increase. The analysis was conducted for both non-insulated and insulated tank cars and used two objective functions, minimization of conditional probability of release, and minimization of expected quantity lost, given that a car was derailed in an accident. Sensitivity analyses of the effect of tank car size and use of different objective functions were conducted and the optimality results were found to be robust. The results of this analysis were used by the Association of American Railroads Tank Car Committee to develop new specifications for higher capacity non-insulated and insulated, non-pressure tank cars resulting in an estimated 32% and 24% respective

  8. Added Sugars

    ... Restaurant Deciphering the Menu Ordering Your Meal Eating Fast Food Dining Out Tips by Cuisine Physical Activity Fitness ... Learn more about reading food labels . Limit your consumption of foods with high amounts of added sugars, ...

  9. Optimizing Airspace System Capacity Through a Small Aircraft Transportation System: An Analysis of Economic and Operational Considerations

    Tarry, Scott E.; Bowen, Brent D.

    2001-01-01

    America's air transport system is currently faced with two equally important dilemmas. First, congestion and delays associated with the overburdened hub and spoke system will continue to worsen unless dramatic changes are made in the way air transportation services are provided. Second, many communities and various regions of the country have not benefited from the air transport system, which tends to focus its attention on major population centers. An emerging solution to both problems is a Small Aircraft Transportation System (SATS), which will utilize a new generation of advanced small aircraft to provide air transport services to those citizens who are poorly served by the hub and spoke system and those citizens who are not served at all. Using new innovations in navigation, communication, and propulsion technologies, these aircraft will enable users to safely and reliably access the over 5,000 general aviation landing facilities around the United States. A small aircraft transportation system holds the potential to revolutionize the way Americans travel and to greatly enhance the use of air transport as an economic development tool in rural and isolated communities across the nation.

  10. Rotina computacional e equação simplificada para modelar o transporte de sedimentos num Latossolo Vermelho Distrófico Computational routine and simplified equation for modeling sediment transport capacity in a Dystrophic Hapludox

    Gilmar E. Cerquetani

    2006-08-01

    Full Text Available Os objetivos do presente trabalho foram desenvolver rotina computacional para a solução da equação de Yalin e do diagrama de Shields e avaliar uma equação simplificada para modelar a capacidade de transporte de sedimento num Latossolo Vermelho Distrófico que possa ser utilizada no Water Erosion Prediction Project - WEPP, assim como em outros modelos de predição da erosão do solo. A capacidade de transporte de sedimento para o fluxo superficial foi representada como função-potência da tensão cisalhante, a qual revelou ser aproximação da equação de Yalin. Essa equação simplificada pôde ser aplicada em resultados experimentais oriundos de topografia complexa. A equação simplificada demonstrou acuracidade em relação à equação de Yalin, quando calibrada utilizando-se da tensão média cisalhante. Testes de validação com dados independentes demonstraram que a equação simplificada foi eficiente para estimar a capacidade de transporte de sedimento.The objectives of the present work were to develop a computational routine to solve Yalin equation and Shield diagram and to evaluate a simplified equation for modeling sediment transport capacity in a Dystrophic Hapludox that could be used in the Water Erosion Prediction Project - WEPP, as well as other soil erosion models. Sediment transport capacity for shallow overland flow was represented as a power function of the hydraulic shear stress and which showed to be an approximation to the Yalin equation for sediment transport capacity. The simplified equation for sediment transport could be applied to experimental data from a complex topography. The simplified equation accurately approximated the Yalin equation when calibrated using the mean hydraulic shear stress. Validation tests using independent data showed that the simplified equation had a good performance in predicting sediment transport capacity.

  11. High capacity cask (TN28V) and International Transport System for the return shipment of vitrified high activity wastes

    The reprocessing of spent fuel generates different kinds of wastes. Among them fission products and non fissile actinides represent 98% of the radioactivity; these wastes are separated, concentrated, mixed with molten glass and poured into stainless steel containers. For political reasons, it is necessary to return these vitrified high activity wastes to the foreign countries which have decided to have their spent fuel reprocessed in France. So the transport of vitrified waste is vital for both the reprocessor and the utilities that have trusted the reprocessor and this operation has to be securely performed to give satisfaction to all concerned particles. For that reason Cogema will control the whole transport activity from La Hague plants to the receiving facilities of the customers. Therefore cogema will be responsible of the transport whatever the cask type (transport or storage) and will subcontract the transport operation to experienced companies such as Transnucleaire, PNTL or NTL, who will act on behalf of Cogema. Cogema will be the owner of the transport casks while the storage casks will normally be owned by the customers. Both cask types will of course have to comply with the requirements of La Hague, as published by Cogema

  12. Wormholes in AdS

    Maldacena, Juan; Maoz, Liat

    2004-01-01

    We construct a few Euclidean supergravity solutions with multiple boundaries. We consider examples where the corresponding boundary field theory is well defined on each boundary. We point out that these configurations are puzzling from the AdS/CFT point of view. A proper understanding of the AdS/CFT dictionary for these cases might yield some information about the physics of closed universes.

  13. Road transport emissions and capacity of forests in the region of Athens for sequestring these emissions: carbon flow before and after forest fires

    Petros Chatzimpiros

    2016-06-01

    Full Text Available One important component of the urban contribution to carbon dioxide atmospheric emissions is road transport. Carbon dioxide (CO2 emissions from urban road transport in the centre of Athens recorded over a period of five years (2000–2005 are compared with the carbon sequestration capacity of regional forests, prior to and after the devastating forest fires in Attica in 2007 and 2009, which is the administrative region of Athens. The comparison of carbon flow reveals two complementary aspects of the same socio-environmental issue: persistent sources versus weakening sinks for CO2 within a mixed (urban and rural setting. Road transport emissions are calculated bottom-up using traffic data from in-situ measurements along segments of main roads. The sequestration capacity of forests is estimated by combining satellite images of changes in land cover with literature values of biomass growth rates. Over the study period, the per capita CO2 emissions averaged 0.72 t CO2/cap/year, which is four times higher than the sequestration capacity of forests before and six times higher after the fires. This imbalance highlights the inadequacy of the local carbon sink. Although there is no biogeochemical need to neutralise carbon budgets locally, defining the CO2 flows from urban activities and local ecosystems is likely to raise awareness and promote global environmental sustainability. The results are compared with top-down estimates of CO2 emissions at a regional scale, where suburban areas are dominant, and the differences are discussed in the light of local socioeconomic factors.

  14. Adding Ajax

    Powers, Shelley

    2007-01-01

    Ajax can bring many advantages to an existing web application without forcing you to redo the whole thing. This book explains how you can add Ajax to enhance, rather than replace, the way your application works. For instance, if you have a traditional web application based on submitting a form to update a table, you can enhance it by adding the capability to update the table with changes to the form fields, without actually having to submit the form. That's just one example.Adding Ajax is for those of you more interested in extending existing applications than in creating Rich Internet Applica

  15. Transportation Energy Futures Series: Alternative Fuel Infrastructure Expansion: Costs, Resources, Production Capacity, and Retail Availability for Low-Carbon Scenarios

    Melaina, M. W.; Heath, G.; Sandor, D.; Steward, D.; Vimmerstedt, L.; Warner, E.; Webster, K. W.

    2013-04-01

    Achieving the Department of Energy target of an 80% reduction in greenhouse gas emissions by 2050 depends on transportation-related strategies combining technology innovation, market adoption, and changes in consumer behavior. This study examines expanding low-carbon transportation fuel infrastructure to achieve deep GHG emissions reductions, with an emphasis on fuel production facilities and retail components serving light-duty vehicles. Three distinct low-carbon fuel supply scenarios are examined: Portfolio: Successful deployment of a range of advanced vehicle and fuel technologies; Combustion: Market dominance by hybridized internal combustion engine vehicles fueled by advanced biofuels and natural gas; Electrification: Market dominance by electric drive vehicles in the LDV sector, including battery electric, plug-in hybrid, and fuel cell vehicles, that are fueled by low-carbon electricity and hydrogen. A range of possible low-carbon fuel demand outcomes are explored in terms of the scale and scope of infrastructure expansion requirements and evaluated based on fuel costs, energy resource utilization, fuel production infrastructure expansion, and retail infrastructure expansion for LDVs. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored transportation-related strategies for abating GHGs and reducing petroleum dependence.

  16. Co-current air-water flow in downward sloping pipes: Transport of capacity reducing gas pockets in wastewater mains

    Pothof, I.W.M.

    2011-01-01

    Air-water flow is an undesired condition in many systems for the transportation of water or wastewater. Air in storm water tunnels may get trapped and negatively affect the system. Air pockets in hydropower tunnels or sewers may cause blow-back events and inadmissible pressure spikes. Water pipes an

  17. Species transport mechanisms governing capacity loss in vanadium flow batteries: Comparing Nafion® and sulfonated Radel membranes

    Highlights: • Species transport mechanisms are investigated in Nafion® and s-Radel for VRFBs. • Unlike diffusion in Nafion®, crossover in s-Radel is dominated by convection. • In particular, electro-osmotic convection is the dominant mode in s-Radel. • Change in direction of convection causes a lower crossover in s-Radel. • Hydraulic and electrokinetic permeability are as important as vanadium permeability. -- Abstract: In this study, a 2-D, transient vanadium redox flow battery (VRFB) model was used to investigate and compare the ion transport mechanisms responsible for vanadium crossover in Nafion® 117 and sulfonated Radel (s-Radel) membranes. Specifically, the model was used to distinguish the relative contribution of diffusion, migration, osmotic and electro-osmotic convection to the net vanadium crossover in Nafion® and s-Radel. Model simulations indicate that diffusion is the dominant mode of vanadium transport in Nafion®, whereas convection dominates the vanadium transport through s-Radel due to the lower vanadium permeability, and thus diffusivity of s-Radel. Among the convective transport modes, electro-osmotic convection (i.e., electro-osmotic drag) is found to govern the species crossover in s-Radel due to its higher fixed acid concentration and corresponding free ions in the membrane. Simulations also show that vanadium crossover in s-Radel changes direction during charge and discharge due to the change in the direction of electro-osmotic convection. This reversal in the direction of crossover during charge and discharge is found to result in significantly lower “net” crossover for s-Radel when compared to Nafion®. Comparison of these two membranes also provides guidance for minimizing crossover in VRFB systems and underscores the importance of measuring the hydraulic and the electro-kinetic permeability of a membrane in addition to vanadium diffusion characteristics, when evaluating new membranes for VRFB applications

  18. Co-current air-water flow in downward sloping pipes: Transport of capacity reducing gas pockets in wastewater mains

    Pothof, I.W.M.

    2011-01-01

    Air-water flow is an undesired condition in many systems for the transportation of water or wastewater. Air in storm water tunnels may get trapped and negatively affect the system. Air pockets in hydropower tunnels or sewers may cause blow-back events and inadmissible pressure spikes. Water pipes and wastewater pressure mains in particular are subject to air pocket formation in downward-sloping reaches, such as inverted siphons or terrain slopes. Air pocket accumulation causes energy losses a...

  19. Coordination between water transport capacity, biomass growth, metabolic scaling and species stature in co-occurring shrub and tree species.

    Smith, Duncan D; Sperry, John S

    2014-12-01

    The significance of xylem function and metabolic scaling theory begins from the idea that water transport is strongly coupled to growth rate. At the same time, coordination of water transport and growth seemingly should differ between plant functional types. We evaluated the relationships between water transport, growth and species stature in six species of co-occurring trees and shrubs. Within species, a strong proportionality between plant hydraulic conductance (K), sap flow (Q) and shoot biomass growth (G) was generally supported. Across species, however, trees grew more for a given K or Q than shrubs, indicating greater growth-based water-use efficiency (WUE) in trees. Trees also showed slower decline in relative growth rate (RGR) than shrubs, equivalent to a steeper G by mass (M) scaling exponent in trees (0.77-0.98). The K and Q by M scaling exponents were common across all species (0.80, 0.82), suggesting that the steeper G scaling in trees reflects a size-dependent increase in their growth-based WUE. The common K and Q by M exponents were statistically consistent with the 0.75 of ideal scaling theory. A model based upon xylem anatomy and branching architecture consistently predicted the observed K by M scaling exponents but only when deviations from ideal symmetric branching were incorporated. PMID:25041417

  20. The capacity of Listeria monocytogenes mutants with in-frame deletions in putative ATP-binding cassette transporters to form biofilms and comparison with the wild type

    Marina Ceruso

    2014-02-01

    Full Text Available Listeria monocytogenes (Lm is a food-borne pathogen responsible for human listeriosis, an invasive infection with high mortality rates. Lm has developed efficient strategies for survival under stress conditions such as starvation and wide variations in temperature, pH, and osmolarity. Therefore, Lm can survive in food under multiple stress conditions. Detailed studies to determine the mode of action of this pathogen for survival under stress conditions are important to control Lm in food. It has been shown that genes encoding for ATP-binding cassette (ABC transporters are induced in Lm in food, in particular under stress conditions. Previous studies showed that these genes are involved in sensitivity to nisin, acids, and salt. The aim of this study was to determine the involvement of some ABC transporters in biofilm formation. Therefore, deletion mutants of ABC transporter genes (LMOf2365_1875 and LMOf2365_1877 were created in Lm F2365, and then were compared to the wild type for their capacity to form biofilms. Lm strain F2365 was chosen as reference since the genome is fully sequenced and furthermore this strain is particularly involved in food-borne outbreaks of listeriosis. Our results showed that DLMOf2365_1875 had an increased capacity to form biofilms compared to the wild type, indicating that LMOf2365_1875 negatively regulates biofilm formation. A deeper knowledge on the ability to form biofilms in these mutants may help in the development of intervention strategies to control Lm in food and in the environment.

  1. Transport

    Transport is one of the major causes of environmental damage in Austria. Energy consumption, pollutants emissions, noise emissions, use of surfaces, sealing of surfaces, dissection of ecosystems and impact on landscape are the most significant environmental impacts caused by it. An overview of the transport development of passengers and freight in Austria is presented. Especially the energy consumption growth, carbon dioxide and nitrogen oxide emissions by type of transport, and the emissions development (HC, particle and carbon monoxide) of goods and passengers transport are analyzed covering the years 1980 - 1999. The health cost resulting from transport-related air pollution in Austria is given and measures to be taken for an effective control of the transport sector are mentioned. Figs. 8, Table 1. (nevyjel)

  2. Silicon-enhanced resistance to cadmium toxicity in Brassica chinensis L. is attributed to Si-suppressed cadmium uptake and transport and Si-enhanced antioxidant defense capacity

    A series of hydroponics experiments were performed to investigate roles of silicon (Si) in enhancing cadmium (Cd) tolerance in two pakchoi (Brassica chinensis L.) cultivars: i.e. cv. Shanghaiqing, a Cd-sensitive cultivar, and cv. Hangyoudong, a Cd-tolerant cultivar. Plants were grown under 0.5 and 5 mg Cd L-1 Cd stress without or with 1.5 mM Si. Plant growth of the Cd-tolerant cultivar was stimulated at the lower Cd level, but was decreased at the higher Cd level when plants were treated with Cd for one week. However, Plant growth was severely inhibited at both Cd levels as stress duration lasted for up to three weeks. Plant growth of the Cd-sensitive cultivar was severely inhibited at both Cd levels irrespective of Cd stress duration. Addition of Si increased shoot and root biomass of both cultivars at both Cd levels and decreased Cd uptake and root-to-shoot transport. Superoxide dismutase, catalase and ascorbate peroxidase activities decreased, but malondialdehyde and H2O2 concentrations increased at the higher Cd level, which were counteracted by Si added. Ascorbic acid, glutathione and non-protein thiols concentrations increased at the higher Cd level, which were further intensified by addition of Si. The effects of Si and Cd on the antioxidant enzyme activity were further verified by isoenzyme analysis. Silicon was more effective in enhancing Cd tolerance in the Cd-tolerant cultivar than in the Cd-sensitive cultivar. It can be concluded that Si-enhanced Cd tolerance in B. chinensis is attributed mainly to Si-suppressed Cd uptake and root-to-shoot Cd transport and Si-enhanced antioxidant defense activity.

  3. Silicon-enhanced resistance to cadmium toxicity in Brassica chinensis L. is attributed to Si-suppressed cadmium uptake and transport and Si-enhanced antioxidant defense capacity

    Song Alin [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Li Zhaojun [Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081 (China); Zhang Jie [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Xue Gaofeng; Fan Fenliang [Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081 (China); Liang Yongchao, E-mail: ycliang@caas.ac.cn [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081 (China); Key Laboratory of Oasis Eco-Agriculture, College of Agriculture, Shihezi University, Shihezi 832003 (China)

    2009-12-15

    A series of hydroponics experiments were performed to investigate roles of silicon (Si) in enhancing cadmium (Cd) tolerance in two pakchoi (Brassica chinensis L.) cultivars: i.e. cv. Shanghaiqing, a Cd-sensitive cultivar, and cv. Hangyoudong, a Cd-tolerant cultivar. Plants were grown under 0.5 and 5 mg Cd L{sup -1} Cd stress without or with 1.5 mM Si. Plant growth of the Cd-tolerant cultivar was stimulated at the lower Cd level, but was decreased at the higher Cd level when plants were treated with Cd for one week. However, Plant growth was severely inhibited at both Cd levels as stress duration lasted for up to three weeks. Plant growth of the Cd-sensitive cultivar was severely inhibited at both Cd levels irrespective of Cd stress duration. Addition of Si increased shoot and root biomass of both cultivars at both Cd levels and decreased Cd uptake and root-to-shoot transport. Superoxide dismutase, catalase and ascorbate peroxidase activities decreased, but malondialdehyde and H{sub 2}O{sub 2} concentrations increased at the higher Cd level, which were counteracted by Si added. Ascorbic acid, glutathione and non-protein thiols concentrations increased at the higher Cd level, which were further intensified by addition of Si. The effects of Si and Cd on the antioxidant enzyme activity were further verified by isoenzyme analysis. Silicon was more effective in enhancing Cd tolerance in the Cd-tolerant cultivar than in the Cd-sensitive cultivar. It can be concluded that Si-enhanced Cd tolerance in B. chinensis is attributed mainly to Si-suppressed Cd uptake and root-to-shoot Cd transport and Si-enhanced antioxidant defense activity.

  4. [Distribution and Transportation Characteristics of Heavy Metals in Nanshan Laolongdong Subterranean River System and Its Capacity of Self-Purification in Chongqing].

    Ren, Kun; Liang, Zuo-bing; Yu, Zheng-liang; Zhang, Yu; Wang, Rong; Yuan, Dao-xian

    2015-11-01

    For figuring out the distribution and transportation characteristics of heavy metals Mn, Pb, Cu and As among overlying water-pore water-surface sediments so as to offer a scientific basis for the development of urban construction and protection of karst groundwater, overlying water, pore water and surface sediment samples were collected in December 2013 ( winter) and June 2014 (summer) respectively. Results show that the detection rates of Mn, Pb, Cu and As are 100% both in overlying water and pore water with the concentration Mn > Pb > Cu > As, summer > winter, pore water > overlying water, respectively, and the groundwater could not be a source of drinking water because of the excessive content of Mn and Pb. In addition, the concentration of heavy metals Mn, Pb, Cu and As in pore water are higher than that in overlying water, indicating that heavy metals could diffuse into overlying water from pore water because of concentration gradient, especially in summertime. Moreover, study also finds that heavy metals are accumulated in surface sediments, the total content of four heavy metals has a decreasing trend between UGR6( sampling site 7) and UGR5 (sampling site 6), but has an increasing trend from UGR5 (sampling site 6) to URG0 (sampling site 1). Mn, in surface sediments, has strong instability and mobility, which can not only cause the pollution of overlying water but also enlarge contaminated area. In a word, Laolongdong subterranean river has strong capacity of self-purification, especially the surface sediments. PMID:26910995

  5. Multi-dimensional boron transport modeling in subchannel approach: Part II. Validation of CTF boron tracking model and adding boron precipitation model

    Highlights: • Validation of implemented multi-dimensional subchannel boron transport model. • Extension of boron transport model to entrained droplets. • Implementation of boron precipitation model. • Testing of the boron precipitation model under transient condition. - Abstract: The risk of small-break loss of coolant accident (SB-LOCA) and other reactivity initiated transients caused by boron dilution in the light water reactors (LWRs), and the complications of tracking the soluble boron concentration experimentally inside the primary coolant have stimulated the interest in computational studies for accurate boron tracking simulations in nuclear reactors. In Part I of this study, the development and implementation of a multi-dimensional boron transport model with modified Godunov scheme based on a subchannel approach within the COBRA-TF (CTF) thermal-hydraulic code was presented. The modified Godunov scheme approach with a physical diffusion term was determined to provide the most accurate and precise solution. Current paper extends these conclusions and presents the model validation studies against experimental data from the Rossendorf coolant mixing model (ROCOM) test facility. In addition, the importance of the two-phase flow characteristics in modeling boron transient are emphasized, especially during long-term cooling period after the loss of coolant accident (LOCA) condition in pressurized water reactors (PWRs). The CTF capabilities of boron transport modeling are further improved based on the three-field representation of the two-phase flow utilized in the code. The boron transport within entrained droplets is modeled, and a model for predicting the boron precipitation under transient conditions is developed and tested. It is aimed to extend the applicability of CTF to reactor transient simulations, and particularly to a large-break loss of coolant accident (LB-LOCA) analysis

  6. Online Ad Assignment with an Ad Exchange

    Dvořák, Wolfgang; Henzinger, Monika

    2016-01-01

    Ad exchanges are becoming an increasingly popular way to sell advertisement slots on the internet. An ad exchange is basically a spot market for ad impressions. A publisher who has already signed contracts reserving advertisement impressions on his pages can choose between assigning a new ad impression for a new page view to a contracted advertiser or to sell it at an ad exchange. This leads to an online revenue maximization problem for the publisher. Given a new impression to sell decide whe...

  7. Research on Impact of Changing Business Tax to Value-added Tax on Transportation Industry and Countermeasures%“营改增”对交通运输业的影响及对策研究

    侯寓栋

    2015-01-01

    我国交通运输业现有的营业税政策存在较多弊端,根据本次营业税改征增值税中交通运输业的改革方案及实施情况,提出了此次改革可能存在的问题。%There are many problems in present business tax policies in transportation industry. This paper aims to put forward some solutions to the problems in reform from imposing business tax to value-added tax.

  8. Carrying Capacity

    Schroll, Henning; Andersen, Jan; Kjærgård, Bente

    2012-01-01

    carrying capacity (SCC) and assimilative carrying capacity (ACC). The act mandates that the latter two aspects must be taken into consideration in the local spatial plans. The present study aimed at developing a background for a national guideline for carrying capacity in Indonesian provinces and districts...... carrying capacity (ACC). The act mandates that the latter two aspects must be taken into consideration in the local spatial plans. The present study aimed at developing a background for a national guideline for carrying capacity in Indonesian provinces and districts/cities. Four different sectors (water...

  9. Wireless Ad Hoc Networks

    Hong-Chuan Yang

    2007-01-01

    Full Text Available We study the energy-efficient configuration of multihop paths with automatic repeat request (ARQ mechanism in wireless ad hoc networks. We adopt a cross-layer design approach and take both the quality of each radio hop and the battery capacity of each transmitting node into consideration. Under certain constraints on the maximum tolerable transmission delay and the required packet delivery ratio, we solve optimization problems to jointly schedule the transmitting power of each transmitting node and the retransmission limit over each hop. Numerical results demonstrate that the path configuration methods can either significantly reduce the average energy consumption per packet delivery or considerably extend the average lifetime of the multihop route.

  10. Two AdS2 branes in the euclidean AdS3

    We compute the density of open strings stretching between AdS2 branes in the euclidean AdS3. This is done by solving the factorization constraint of a degenerate boundary field, and the result is checked by a Cardy-type computation. We mention applications to branes in the minkowskian AdS3 and its cigar coset. (author)

  11. Two AdS2 branes in the Euclidean AdS3

    Ribault, S

    2003-01-01

    We compute the density of open strings stretching between AdS2 branes in the Euclidean AdS3. This is done by solving the factorization constraint of a degenerate boundary field, and the result is checked by a Cardy-type computation. We mention applications to branes in the Minkowskian AdS3 and its cigar coset.

  12. AdS solutions through transgression

    We present new classes of explicit supersymmetric AdS3 solutions of type IIB supergravity with non-vanishing five-form flux and AdS2 solutions of D=11 supergravity with electric four-form flux. The former are dual to two-dimensional SCFTs with (0,2) supersymmetry and the latter to supersymmetric quantum mechanics with two supercharges. We also investigate more general classes of AdS3 solutions of type IIB supergravity and AdS2 solutions of D=11 supergravity which in addition have non-vanishing three-form flux and magnetic four-form flux, respectively. The construction of these more general solutions makes essential use of the Chern-Simons or ''transgression'' terms in the Bianchi identity or the equation of motion of the field strengths in the supergravity theories. We construct infinite new classes of explicit examples and for some of the type IIB solutions determine the central charge of the dual SCFTs. The type IIB solutions with non-vanishing three-form flux that we construct include a two-torus, and after two T-dualities and an S-duality, we obtain new AdS3 solutions with only the NS fields being non-trivial. (orig.)

  13. Polarised Black Holes in AdS

    Costa, Miguel S; Oliveira, Miguel; Penedones, João; Santos, Jorge E

    2015-01-01

    We consider solutions in Einstein-Maxwell theory with a negative cosmological constant that asymptote to global $AdS_{4}$ with conformal boundary $S^{2}\\times\\mathbb{R}_{t}$. At the sphere at infinity we turn on a space-dependent electrostatic potential, which does not destroy the asymptotic $AdS$ behaviour. For simplicity we focus on the case of a dipolar electrostatic potential. We find two new geometries: (i) an $AdS$ soliton that includes the full backreaction of the electric field on the $AdS$ geometry; (ii) a polarised neutral black hole that is deformed by the electric field, accumulating opposite charges in each hemisphere. For both geometries we study boundary data such as the charge density and the stress tensor. For the black hole we also study the horizon charge density and area, and further verify a Smarr formula. Then we consider this system at finite temperature and compute the Gibbs free energy for both $AdS$ soliton and black hole phases. The corresponding phase diagram generalizes the Hawkin...

  14. Heat Capacity Analysis Report

    The purpose of this report is to provide heat capacity values for the host and surrounding rock layers for the waste repository at Yucca Mountain. The heat capacity representations provided by this analysis are used in unsaturated zone (UZ) flow, transport, and coupled processes numerical modeling activities, and in thermal analyses as part of the design of the repository to support the license application. Among the reports that use the heat capacity values estimated in this report are the ''Multiscale Thermohydrologic Model'' report, the ''Drift Degradation Analysis'' report, the ''Ventilation Model and Analysis Report, the Igneous Intrusion Impacts on Waste Packages and Waste Forms'' report, the ''Dike/Drift Interactions report, the Drift-Scale Coupled Processes (DST and TH Seepage) Models'' report, and the ''In-Drift Natural Convection and Condensation'' report. The specific objective of this study is to determine the rock-grain and rock-mass heat capacities for the geologic stratigraphy identified in the ''Mineralogic Model (MM3.0) Report'' (BSC 2004 [DIRS 170031], Table 1-1). This report provides estimates of the heat capacity for all stratigraphic layers except the Paleozoic, for which the mineralogic abundance data required to estimate the heat capacity are not available. The temperature range of interest in this analysis is 25 C to 325 C. This interval is broken into three separate temperature sub-intervals: 25 C to 95 C, 95 C to 114 C, and 114 C to 325 C, which correspond to the preboiling, trans-boiling, and postboiling regimes. Heat capacity is defined as the amount of energy required to raise the temperature of a unit mass of material by one degree (Nimick and Connolly 1991 [DIRS 100690], p. 5). The rock-grain heat capacity is defined as the heat capacity of the rock solids (minerals), and does not include the effect of water that exists in the rock pores. By comparison, the rock-mass heat capacity considers the heat capacity of both solids and pore

  15. Enhanced Wireless Network Ad Hoc Pattern

    M. Kamalakannan

    2012-06-01

    Full Text Available Early simulation experience with wireless ad hoc networks suggests that their capacity can be surprisingly low, due to the requirement that nodes forward each others’ packets. The achievable capacity depends on network size, traffic patterns and detailed local radio interactions. This study examines these factors alone and in combination, using simulation and analysis from first principles. Our results include both specific constants and general relationship Scaling helpful in understanding the limitations of wireless ad hoc networks. We examine interactions of the 802.11 MAC and ad hoc forwarding and the effect on capacity for several simple configurations and traffic patterns. While 802.11 discovers reasonably good schedules, we nonetheless observe capacities markedly less than optimal for very simple chain and lattice networks with very regular traffic patterns. We validate some simulation results with experiments. We also show that the traffic pattern determines whether an ad hoc network’s per node capacity will scale to large networks. In particular, we show that for total capacity to scale up with network size the average distance between source and destination nodes must remain small as the network grows. Nonlocal traffic patterns in which this average distance grows with the network size result in a rapid decrease of per node capacity.

  16. Baby Skyrmions in AdS

    Elliot-Ripley, Matthew; Winyard, Thomas

    2015-01-01

    We study the baby Skyrme model in a pure AdS background without a mass term. The tail decays and scalings of massless radial solutions are demonstrated to take a similar form to those of the massive flat space model, with the AdS curvature playing a similar role to the flat space pion mass. We also numerically find minimal energy solutions for a range of higher topological charges and find that they form concentric ring-like solutions. Popcorn transitions (named in analogy with studies of toy...

  17. Eternal Black Holes in AdS

    Maldacena, Juan M.

    2001-01-01

    We propose a dual non-perturbative description for maximally extended Schwarzschild Anti-de-Sitter spacetimes. The description involves two copies of the conformal field theory associated to the AdS spacetime and an initial entangled state. In this context we also discuss a version of the information loss paradox and its resolution.

  18. AdS braneworld with Backreaction

    Bilić Neven; Tupper Gary

    2013-01-01

    We review the tachyon model derived from the dynamics of a 3-brane moving in the AdS5 bulk. The bulk geometry is based on the Randall-Sundrum II model extended to include the radion. The effective tachyon Lagrangian is modified due to the back-reaction of the brane on the bulk geometry.

  19. Current status of AdS instability

    CERN. Geneva

    2016-01-01

    arXiv:1403.6471 and thoroughly developed in arXiv:1407.6273. On the other hand the negative cosmological constant allows for the existence of stable, time-periodic, asymptotically AdS solutions of Einstein equations [arXiv:1303.3186].

  20. AdS braneworld with Backreaction

    Bilic, Neven

    2014-01-01

    We review the tachyon model derived from the dynamics of a 3-brane moving in the AdS5 bulk. The bulk geometry is based on the Randall-Sundrum II model extended to include the radion. The effective tachyon Lagrangian is modified due to the back-reaction of the brane on the bulk geometry.

  1. ADS National Programmes: Germany

    The German R&D programme for ADS development is related to the partitioning and transmutation of spent fuel. This programme is implemented mainly by the three national research centres belonging to the Helmholtz Association, i.e. Karlsruhe Institute of Technology (KIT), Forschungszentrum Jülich (FZJ) in cooperation with the Technical University of Aachen (RWTH Aachen) and the Helmholtz Zentrum Dresden Rossendorf (HZDR). The main purpose of this R&D programme is the prospect to manage the high level radioactive waste such as to reduce the burden on a final repository. P&T does not eliminate the need for a final repository whatever the strategy, but it allows the reduction of the radio-toxicity associated with radioactive waste, the increase of the repository capacity as a consequence of the reduction of masses to be stored and their associated residual heat load. Different fuel cycle scenarios to implement P&T can be envisaged. These scenarios have been evaluated to identify the impact of P&T on the characteristics, number and deployment pace of the installations of the fuel cycle (reprocessing, fuel fabrication, storage etc). Almost all activities conducted in the R&D programme are embedded in European and international projects and initiatives. In the following more details on the relevant components of the R&D programme are summarized

  2. ADS National Programmes: Netherlands

    The ADS related activities within the Netherlands are concentrated at NRG. From 2000 to 2006, NRG supported SCK•CEN in their development of MYRRHA. The support was mainly devoted to Computational Fluid Dynamics (CFD) simulations for the windowless target option. This collaboration was prolonged within the framework of the EU FP6 EUROTRANS project. Eventually this lead to a solution strategy for the hydraulic (without heat transfer) evaluation of a windowless target with one free surface using an Eulerian-Eulerian modeling approach. As a second free surface was added to the target design later, this approach would need to be revisited. The developed approach was applied to an assess the feasibility of a three feeder windowless target design. This preliminary assessment confirmed that there were no serious show stoppers for a three feeder design. Another study undertaken using related to the windowless target was a preliminary assessment of the risk of lead-bismuth splashing in case of a sudden heat deposition by the beam, e.g. at beam startup or beam interuptions. Within the framework of the EU FP7 CDT project, a window target is currently being assessed thermalhydraulicly in collaboration with SCK•CEN. Within the EU FP5 ASCHLIM project, the state of the art with regard to turbulence modelling for CFD approaches was determined. It was concluded that accurate simulation of heat transport in HLM was not feasible, especially in natural or mixed convection regimes. Within the EU FP7 THINS project this issue is currently being treated. NRG assists the commercial CFD code vendor CD adapco in implementing and testing a promising, academically tested, algebraic heat flux model

  3. Superradiant instability in AdS

    Ganchev, Bogdan

    2016-01-01

    The phenomenon of superradiance in the context of asymptotically global AdS spacetimes is investigated with particular accent on its effect on the stability of the systems under consideration. To this end, the concept of an asymptotically AdS spacetime is explained, together with its implications on the boundary conditions at $\\mathcal{I}$, as well as the Newman-Penrose-Teukolsky formalism, whereby the Teukolsky master equation in a most general form for Kerr-AdS is given. Furthermore, work done in the cases of RN-AdS and Kerr-AdS is laid out in a concise manner, putting emphasis on the important steps taken in determining the endpoint of the superradiant instability in the two configurations. For the former this turns out to be a black hole with reduced charge and a static charged scalar condensate around it, whereas for the latter two of the more probable outcomes are presented, both of which imply a violation of one of the cosmic censorships.

  4. The Influence of Organisational Defensive Patterns on Innovation Capacity and Learning of Information and Communication Technology: An Empirical Study in Hong Kong Transport Sector

    Yau, Hon Keung; Cheng, Alison Lai Fong

    2010-01-01

    Organisational defensive patterns, including skilled incompetence, organisational defensive routines and fancy footwork, are considered to be a hindrance to effective learning and innovation capacity building in all organisations. The purpose of this research is to investigate: 1) the perceptions of the influence of organisational defensive…

  5. Instability corners in AdS space

    Dimitrakopoulos, Fotios V; Lippert, Matthew; Yang, I-Sheng

    2014-01-01

    We investigate whether arbitrarily small perturbations in global AdS space are generically unstable and collapse into black holes on the time scale set by gravitational interactions. We argue that current evidence, combined with our analysis, strongly suggests that a set of nonzero measure in the space of initial conditions does not collapse on this time scale. On the other hand, existing results do not provide an equally strong indication whether the unstable solutions also form a set of nonzero measure. We perform an analysis in position space to address this puzzle, and our formalism allows us to directly address the vanishing-amplitude limit. We show that gravitational self-interaction leads to tidal deformations which are equally likely to focus or defocus energy, and we sketch the phase diagram accordingly. We also clarify the connection between gravitational evolution in global AdS and holographic thermalization.

  6. Baby Skyrmions in AdS

    Elliot-Ripley, Matthew

    2015-01-01

    We study the baby Skyrme model in a pure AdS background without a mass term. The tail decays and scalings of massless radial solutions are demonstrated to take a similar form to those of the massive flat space model, with the AdS curvature playing a similar role to the flat space pion mass. We also numerically find minimal energy solutions for a range of higher topological charges and find that they form concentric ring-like solutions. Popcorn transitions (named in analogy with studies of toy models of holographic QCD) from an n layer to an n+1-layer configuration are observed at topological charges 9 and 27 and further popcorn transitions for higher charges are predicted. Finally, a point-particle approximation for the model is derived and used to successfully predict the ring structures and popcorn transitions for higher charge solitons.

  7. Boson Stars in AdS

    Buchel, Alex; Lehner, Luis

    2013-01-01

    We construct boson stars in global Anti de Sitter (AdS) space and study their stability. Linear perturbation results suggest that the ground state along with the first three excited state boson stars are stable. We evolve some of these solutions and study their nonlinear stability in light of recent work \\cite{Bizon:2011gg} arguing that a weakly turbulent instability drives scalar perturbations of AdS to black hole formation. However evolutions suggest that boson stars are nonlinearly stable and immune to the instability for sufficiently small perturbation. Furthermore, these studies find other families of initial data which similarly avoid the instability for sufficiently weak parameters. Heuristically, we argue that initial data families with widely distributed mass-energy distort the spacetime sufficiently to oppose the coherent amplification favored by the instability. From the dual CFT perspective our findings suggest that there exist families of rather generic initial conditions in strongly coupled CFT ...

  8. Conformal Mass in AdS gravity

    Jatkar, Dileep P; Miskovic, Olivera; Olea, Rodrigo

    2014-01-01

    We show that the Ashtekar-Magnon-Das (AMD) mass and other conserved quantities are equivalent to the Kounterterm charges in the asymptotically AdS spacetimes that satisfy the Einstein equations, if we assume the same asymptotic fall-off behavior of the Weyl tensor as considered by AMD. This therefore implies that, in all dimensions, the conformal mass can be directly derived from the bulk action and the boundary terms, which are written in terms of the extrinsic curvature.

  9. 增值税改革对上海交通运输行业税负的影响%The influence on the transportation industry of the value added tax reform

    陈晓光; 雷良海

    2012-01-01

    The scope of taxation for value added tax and sales tax does not cross,Sales tax put focus on the third industry,based on turnover of service industry,sales tax has been paid,in the next level,the taxpayer also need to pay the sales tax,double taxation phenomenon has been exist.the enterprise has heavy tax burden.During 2011-2015 years,the value added tax reform begin in the transportation industry,in this paper I use the relevant data of input-output tables,the estimate of industry tax burden,analyse the change of tax burden.%增值税和营业税的征税范围没有交叉,营业税主要是以第三产业中的服务业的营业额为征税对象,每个环节都是以营业额为税基,不能抵扣已经缴纳的税收,存在重复征税的现象,增大企业的税收负担。"十二五"期间在上海交通运输行业试点进行营业税改征增值税的改革,利用投入产出表中相关数据,通过对行业税负的测算,分析改革前后交通运输行业的税收负担变化情况。

  10. Probing Capacity

    Asnani, Himanshu; Weissman, Tsachy

    2010-01-01

    We consider the problem of optimal probing of states of a channel by transmitter and receiver for maximizing rate of reliable communication. The channel is discrete memoryless (DMC) with i.i.d. states. The encoder takes probing actions dependent on the message. It then uses the state information obtained from probing causally or non-causally to generate channel input symbols. The decoder may also take channel probing actions as a function of the observed channel output and use the channel state information thus acquired, along with the channel output, to estimate the message. We refer to the maximum achievable rate for reliable communication for such systems as the 'Probing Capacity'. We characterize this capacity when the encoder and decoder actions are cost constrained. To motivate the problem, we begin by characterizing the trade-off between the capacity and fraction of channel states the encoder is allowed to observe, while the decoder is aware of channel states. In this setting of 'to observe or not to o...

  11. Refined holographic entanglement entropy for the AdS solitons and AdS black holes

    We consider the refinement of the holographic entanglement entropy for the holographic dual theories to the AdS solitons and AdS black holes, including the corrected ones by the Gauss–Bonnet term. The refinement is obtained by extracting the UV-independent piece of the holographic entanglement entropy, the so-called renormalized entanglement entropy which is independent of the choices of UV cutoff. Our main results are: (i) the renormalized entanglement entropies of the AdSd+1 soliton for d=4,5 are neither monotonically decreasing along the RG flow nor positive-definite, especially around the deconfinement/confinement phase transition; (ii) there is no topological entanglement entropy for AdS5 soliton even with Gauss–Bonnet correction; (iii) for the AdS black holes, the renormalized entanglement entropy obeys an expected volume law at IR regime, and the transition between UV and IR regimes is a smooth crossover even with Gauss–Bonnet correction; (iv) based on AdS/MERA conjecture, we postulate that the IR fixed-point state for the non-extremal AdS soliton is a trivial product state

  12. Predicting AD conversion

    Liu, Yawu; Mattila, Jussi; Ruiz, Miguel �ngel Mu�oz;

    2013-01-01

    To compare the accuracies of predicting AD conversion by using a decision support system (PredictAD tool) and current research criteria of prodromal AD as identified by combinations of episodic memory impairment of hippocampal type and visual assessment of medial temporal lobe atrophy (MTA) on MRI...

  13. Enhanced Wireless Network Ad Hoc Pattern

    M. Kamalakannan; V. Khanaa

    2012-01-01

    Early simulation experience with wireless ad hoc networks suggests that their capacity can be surprisingly low, due to the requirement that nodes forward each others’ packets. The achievable capacity depends on network size, traffic patterns and detailed local radio interactions. This study examines these factors alone and in combination, using simulation and analysis from first principles. Our results include both specific constants and general relationship Scaling helpful in understanding t...

  14. Winding Strings in AdS_3

    Minces, P; Minces, Pablo; Nunez, Carmen

    2006-01-01

    Correlation functions of one-unit spectral flowed states in string theory on AdS_3 are considered. We present a formalism which allows to explicitly find the modified Knizhnik-Zamolodchikov and null vector equations to be satisfied by amplitudes of states in w=1 sectors. We give a precise prescription to solve this system of linear differential equations in cases that are relevant to obtain three and four point functions involving spectral flowed string states. We specifically compute three point functions with two and three one-unit spectral flowed operators and also discuss four point functions.

  15. Capacity Building

    Outcomes & Recommendations: • Significant increase needed in the nuclear workforce both to replace soon-to-retire current generation and to staff large numbers of new units planned • Key message, was the importance of an integrated approach to workforce development. • IAEA and other International Organisations were asked to continue to work on Knowledge Management, Networks and E&T activities • IAEA requested to conduct Global Survey of HR needs – survey initiated but only 50% of operating countries (30% of capacity) took part, so results inconclusive

  16. Study on the Adaptability and Solution of the Channel Capacity of Railway Transportation of Coal%广西煤炭铁路运输通道能力适应性分析及对策研究

    陆达飞

    2011-01-01

    在分析预测广西煤炭需求及各铁路煤炭运量基础上,针对区域既有煤炭运输通道运煤能力与预测煤炭运量之间不足的情况,提出了需重点建设的煤炭铁路运输通道项目:近期南昆线增建二线、黔桂线麻尾~金城江段新建双线、金城江~柳州段增建二线、焦柳线电气化改造、湘桂线电气化改造,远期焦柳线增建二线;最后对各主要煤炭运输通道能力适应性进行分析后认为,重点煤炭铁路运输通项目实施后,区域能源安全和经济结构调整将得到充分保障。%Based on the analysis and prediction of the coal demand and railway transportation volume of coal,to solve the differences between the existing coal transportation capacity and the expected transportation volume,railway project of coal transportation is proposed:construction of second line Nankun railway second line,second line for Guiqian railway,Mawei-Jincheng section,Jinchengjiang-Lvzhou section.At last,after an analysis of the adaptability of railway transportation,it proves that the regional energy safty and the adjustment of economic structure can be ensured by the construction of key coal transportation railway.

  17. Probing crunching AdS cosmologies

    Kumar, S. Prem; Vaganov, Vladislav

    2016-02-01

    Holographic gravity duals of deformations of CFTs formulated on de Sitter spacetime contain FRW geometries behind a horizon, with cosmological big crunch singularities. Using a specific analytically tractable solution within a particular single scalar truncation of {N}=8 supergravity on AdS4, we first probe such crunching cosmologies with spacelike radial geodesics that compute spatially antipodal correlators of large dimension boundary operators. At late times, the geodesics lie on the FRW slice of maximal expansion behind the horizon. The late time two-point functions factorise, and when transformed to the Einstein static universe, they exhibit a temporal non-analyticity determined by the maximal value of the scale factor ã max. Radial geodesics connecting antipodal points necessarily have de Sitter energy Ɛ ≲ ã max, while geodesics with Ɛ > ã max terminate at the crunch, the two categories of geodesics being separated by the maximal expansion slice. The spacelike crunch singularity is curved "outward" in the Penrose diagram for the deformed AdS backgrounds, and thus geodesic limits of the antipodal correlators do not directly probe the crunch. Beyond the geodesic limit, we point out that the scalar wave equation, analytically continued into the FRW patch, has a potential which is singular at the crunch along with complex WKB turning points in the vicinity of the FRW crunch. We then argue that the frequency space Green's function has a branch point determined by ã max which corresponds to the lowest quasinormal frequency.

  18. Adding Flavor to AdS4/CFT3

    Ammon, Martin; Meyer, Rene; O'Bannon, Andy; Wrase, Timm

    2009-01-01

    Aharony, Bergman, Jafferis, and Maldacena have proposed that the low-energy description of multiple M2-branes at a C4/Zk singularity is a (2+1)-dimensional N=6 supersymmetric U(Nc) x U(Nc) Chern-Simons matter theory, the ABJM theory. In the large-Nc limit, its holographic dual is supergravity in AdS4 x S7/Zk. We study various ways to add fields that transform in the fundamental representation of the gauge groups, i.e. flavor fields, to the ABJM theory. We work in a probe limit and perform analyses in both the supergravity and field theory descriptions. In the supergravity description we find a large class of supersymmetric embeddings of probe flavor branes. In the field theory description, we present a general method to determine the couplings of the flavor fields to the fields of the ABJM theory. We then study four examples in detail: codimension-zero N=3 supersymmetric flavor, described in supergravity by Kaluza-Klein monopoles or D6-branes; codimension-one N=(0,6) supersymmetric chiral flavor, described by...

  19. Twistor methods for AdS$_5$

    Adamo, Tim; Williams, Jack

    2016-01-01

    We consider the application of twistor theory to five-dimensional anti-de Sitter space. The twistor space of AdS$_5$ is the same as the ambitwistor space of the four-dimensional conformal boundary; the geometry of this correspondence is reviewed for both the bulk and boundary. A Penrose transform allows us to describe free bulk fields, with or without mass, in terms of data on twistor space. Explicit representatives for the bulk-to-boundary propagators of scalars and spinors are constructed, along with twistor action functionals for the free theories. Evaluating these twistor actions on bulk-to-boundary propagators is shown to produce the correct two-point functions.

  20. Probing crunching AdS cosmologies

    Kumar, S Prem

    2015-01-01

    Holographic gravity duals of deformations of CFTs formulated on de Sitter spacetime contain FRW geometries behind a horizon, with cosmological big crunch singularities. Using a specific analytically tractable solution within a particular single scalar truncation of N=8 supergravity on AdS_4, we first probe such crunching cosmologies with spacelike radial geodesics that compute spatially antipodal correlators of large dimension boundary operators. At late times, the geodesics lie on the FRW slice of maximal expansion behind the horizon. The late time two-point functions factorise, and when transformed to the Einstein static universe, they exhibit a temporal non-analyticity determined by the maximal value of the scale factor a_{max} . Radial geodesics connecting antipodal points necessarily have de Sitter energy E \\leq a_{max}, while geodesics with E > a_{max} terminate at the crunch, the two categories of geodesics being separated by the maximal expansion slice. The spacelike crunch singularity is curved "outw...

  1. Holography of AdS vacuum bubbles

    We consider the fate of AdS vacua connected by tunneling events. A precise holographic dual of thin-walled Coleman-de Luccia bounces is proposed in terms of Fubini instantons in an unstable CFT. This proposal is backed by several qualitative and quantitative checks, including the precise calculation of the instanton action appearing in evaluating the decay rate. Big crunches manifest themselves as time dependent processes which reach the boundary of field space in a finite time. The infinite energy difference involved is identified on the boundary and highlights the ill-defined nature of the bulk setup. We propose a qualitative scenario in which the crunch is resolved by stabilizing the CFT, so that all attempts at crunching always end up shielded from the boundary by the formation of black hole horizons. In all these well defined bulk processes the configurations have the same asymptotics and are finite energy excitations.

  2. AdS3: the NHEK generation

    Bena, Iosif; Heurtier, Lucien; Puhm, Andrea

    2016-05-01

    It was argued in [1] that the five-dimensional near-horizon extremal Kerr (NHEK) geometry can be embedded in String Theory as the infrared region of an infinite family of non-supersymmetric geometries that have D1, D5, momentum and KK monopole charges. We show that there exists a method to embed these geometries into asymptotically- {AdS}_3× {S}^3/{{Z}}_N solutions, and hence to obtain infinite families of flows whose infrared is NHEK. This indicates that the CFT dual to the NHEK geometry is the IR fixed point of a Renormalization Group flow from a known local UV CFT and opens the door to its explicit construction.

  3. An in situ experimental study of Zr4+ transport capacity of water-rich fluids in the temperature and pressure range of the deep crust and upper mantle

    Mysen, Bjorn

    2015-12-01

    Throughout the Earth's history, mass transport involved fluids. In order to address the circumstances under which Zr4+ may have been transported in this manner, its solubility behavior in aqueous fluid with and without NaOH and SiO2 in equilibrium with crystalline ZrO2 was determined from 550 to 950 °C and 60 to 1200 MPa. The measurements were carried out in situ while the samples were at the temperatures and pressures of interest. In ZrO2-H2O and ZrO2-SiO2-H2O fluids, the Zr4+ concentration ranges from ≤10 to ~70 ppm with increasing temperature and pressure. Addition of SiO2 to the ZrO2-H2O system does not affect these values appreciably. In these two environments, Zr4+ forms simple oxide complexes in the H2O fluid with ∆H ~ 40 kJ/mol for the solution equilibrium, ZrO2(solid) = ZrO2(fluid). The Zr4+ concentration in aqueous fluid increases about an order of magnitude upon addition of 1 M NaOH, which reflects the formation of zirconate complexes. The principal solution mechanism is ZrO2 + 4NaOH = Na4ZrO4 + 2H2O with ∆H ~ 200 kJ/mol. Addition of both SiO2 and NaOH to ZrO2-H2O enhances the Zr4+ by an additional factor of about 5 with the formation of partially protonated alkali zircon silicate complexes in the fluid. The principal solution mechanism is 2ZrO2 + 2NaOH + 2SiO2 = Na2Zr2Si2O9 + H2O with ∆H ~ 40 kJ/mol. These results, in combination with other published experimental data, imply that fluid released during high-temperature/high-pressure dehydration of hydrous mineral assemblages in the Earth's interior under some circumstances may carry significant concentrations of Zr and probably other high field strength elements (HFSEs). This suggestion is consistent with the occurrence of Zr-rich veins in high-grade metamorphic eclogite and granulite terranes. Moreover, aqueous fluids transported from dehydrating oceanic crust into overlying mantle source rocks of partial melting also may carry high-abundance HFSE of fluids released from dehydrating slabs and

  4. Increasing the reliability and capacity of Ukrainian gas transit system; Augmentation de la capacite et de la fiabilite du systeme Ukrainien de transport du gaz

    Rozgonyk, V.; Osinchuk, Z. [Naftogaz of Ukraine (Ukraine)

    2000-07-01

    Ukrainian gas transmission system plays a key role in the transit deliveries of Russian natural gas to European countries. Therefore special attention is paid to reliability and efficiency of the existing gas pipelines. The in-line inspections of pipelines as well as update methods of corrosion pipeline protection control and developed vibration diagnostic system for gas compressor units are used on a large scale. The program for gas transmission pipeline reconstruction and upgrading of 50 compressor stations of main lines is being under realization. Modernization of compressor stations will allow to increase turbine drivers' efficiency up to 34-36 per cent to save about 1-10{sup 9} cubic meters of fuel gas annually. The reliability of gas transit deliveries is supported by powerful underground gas storage facilities, situated mostly in the Western Ukraine. The expansion of gas pipe lines system is carried out that will increase transit capacity of Ukrainian gas trunk lines up to 160 -10{sup 9} cubic meters a year. (authors)

  5. ADS National Programmes: India

    Initial preliminary studies in India on ADS concepts were aimed toward applications such as, one way coupled booster reactor concept, thorium burner concept, enhancement of breeding rate of thorium– fueled fast reactors, and to incinerate Pu and minor actinides discharged from heavy water and fast reactors. These studies led to a roadmap on development of ADS subsystems in India, which was chalked out initially in June 2001. It was realized in these studies that the most challenging subsystem in terms of technology development and capital investment for ADS in India would be the high intensity proton accelerator, and that it must be accomplished in phased manner. Of the two alternative accelerator types, viz. the cyclotron and linear accelerator (linac), it is concluded that only linac would provide the necessary intense beam current for ADS applications. The energy amplifier (EA) scheme, with lead (45.5%) bismuth (55.5%) eutectic (LBE) as target & coolant, which was proposed in the early nineties would be one of the desired configurations of ADS for Indian applications. Additionally, subcritical reactor core of Indian Advanced Heavy Water Reactor (AHWR), with advantages of its low fission power density, and neutron economy is also a candidate among various ADS reactor configurations. These options of ADS configurations for thorium utilization are based on the neutronic properties of 233U isotope as fissile fuel, which are more or less similar in thermal and in moderately fast neutron spectra

  6. Ehrenfest's scheme and thermodynamic geometry in Born-Infeld AdS black holes

    Lala, Arindam; Roychowdhury, Dibakar

    2011-01-01

    In this paper we analyze the phase transition phenomena in Born-Infeld AdS black holes using Ehrenfest's scheme of standard thermodynamics. The critical points are marked by the divergences in the heat capacity. In order to investigate the nature of the phase transition, we analytically check both the Ehrenfest's equations near the critical points. Our analysis reveals that this is indeed a second order phase transition. Finally, we analyze the nature of the phase transition using state space...

  7. Optimizing Railroad Tank Car Safety Design to Reduce Hazardous Materials Transportation Risk

    Saat, Mohd Rapik

    2009-01-01

    The design of railroad tank cars is subject to structural and performance requirements and constrained by weight. They can be made safer by increasing tank thickness and adding various protective features, but these increase the weight and cost of the car and reduce its capacity and consequent transportation efficiency. Aircraft, automobiles and…

  8. Heat removal capacity of steam generators under unsteady reflux condensation cooling mode in a pressurized water reactor primary heat transport system

    In a figure-of-eight configuration of the primary heat transport loop of a nuclear power plant, such as in the CANDU design, experimental observations have shown that reflux condensation in the steam generator tubes may become the major natural circulation mode for removing long-term decay heat under reduced water inventories following a LOCA. The resulting two-phase flow in the reactor core may exhibit oscillatory modes in which the steam flow to each steam generator is oscillatory in nature. The present study was aimed at investigating the transient characteristics of the reflux condensation phenomenon under conditions in which the steam flow was oscillatory, especially with respect to its heat removal capability under such conditions. Various frequencies of oscillations in the inlet steam flow were investigated over a range of average mass flow rates. Experimental results showed that oscillations in the steam flow destabilized the water column formation associated with flooding in the tube and further suggest that the total heat removal capability of reflux condensation would be much higher than the values obtained from steady steam flow experiments. (author)

  9. Increment of capacity of casks for PWR spent fuel transport. (1) Analysis taking into account pin-wised distribution of nuclides for introduction of burn-up credit

    Subcriticality of a fuel assembly immersed in light water is studied to take burn-up credit for spent fuel transport. For the purpose, pin-wised nuclide density distribution in a typical PWR spent fuel assembly is evaluated with a code used for designing of fuel loading patterns in commercial PWRs. Taking the heterogeneous distribution into account, multiplication and radiation of neutrons inside / outside the assembly is analyzed with MCNP-5 and SOURCES-4C. As the results, neutron leakage ratio to water surrounding the assembly is found to vary little with burn-up of the assembly so that total neutron yield can be estimated by measuring neutron absorption in the water. Provided 252Cf of known intensity is inserted to the assembly, the subcritical multiplication factor ksub is evaluated by the number of neutron absorption. If not 252Cf but Sb-Be is only available, it is recommended to measure spatial decay constant in middle height of the assembly with it by the exponential method. The axial buckling which is the square of the constant is found to be a good indicator for burn-up of the assembly. (author)

  10. Capacity Value of Concentrating Solar Power Plants

    Madaeni, S. H.; Sioshansi, R.; Denholm, P.

    2011-06-01

    This study estimates the capacity value of a concentrating solar power (CSP) plant at a variety of locations within the western United States. This is done by optimizing the operation of the CSP plant and by using the effective load carrying capability (ELCC) metric, which is a standard reliability-based capacity value estimation technique. Although the ELCC metric is the most accurate estimation technique, we show that a simpler capacity-factor-based approximation method can closely estimate the ELCC value. Without storage, the capacity value of CSP plants varies widely depending on the year and solar multiple. The average capacity value of plants evaluated ranged from 45%?90% with a solar multiple range of 1.0-1.5. When introducing thermal energy storage (TES), the capacity value of the CSP plant is more difficult to estimate since one must account for energy in storage. We apply a capacity-factor-based technique under two different market settings: an energy-only market and an energy and capacity market. Our results show that adding TES to a CSP plant can increase its capacity value significantly at all of the locations. Adding a single hour of TES significantly increases the capacity value above the no-TES case, and with four hours of storage or more, the average capacity value at all locations exceeds 90%.

  11. Antiproton-Decelerator (AD)

    Laurent Guiraud

    1998-01-01

    When the Low-Energy Antiproton Ring (LEAR) was stopped in 1996, because of its costly operation, a cheaper way of continuing low-energy antiproton physics was sought. The Antiproton-Collector (AC), added in 1987 to the Antiproton Accumulator (AA) to provide a tenfold intensity increase, was converted into the Antiproton-Decelerator (AD). Antiprotons from the target at 3.5 GeV/c are decelerated to 100 MeV/c, and fast-ejected to the experiments. Major changes were necessary. Above all, the conversion from a constant-field machine to one with a magnetic cycle, modulating the field by an impressive factor 35. New systems for stochastic and electron cooling had to be added. Beam diagnostics at an intensity of only 2E7 antiprotons was a challenge. In 2000, the AD began delivery of antiprotons to the experiments.

  12. Value Adding Management

    Jensen, Per Anker; Katchamart, Akarapong

    2011-01-01

    Purpose: To investigate how Facilities Management (FM) can add value and develop a management concept that can assist facilities managers in implementing value adding strategies and practices. Theory: The study is based on the management model for FM included in the European FM standards, recent...... theories on added value of FM and real estate and the related concept of Value Management from building projects. The study is related to the EuroFM research group on The Added Value of FM. Design/methodology/approach: The study outlines a preliminary theoretical based management concept, which...... is investigated, tested and discussed based on a case study of an international corporation. Findings: The study shows that the management model for FM creates a relevant starting point but also that stakeholder and relationship management is an essential aspect of Value Adding Management. The case study confirms...

  13. Coopetitive Ad Auctions

    Hoy, Darrell; Jain, Kamal; Wilkens, Christopher A.

    2012-01-01

    A single advertisement often benefits many parties, for example, an ad for a Samsung laptop benefits Microsoft. We study this phenomenon in search advertising auctions and show that standard solutions, including the status quo ignorance of mutual benefit and a benefit-aware Vickrey-Clarke-Groves mechanism, perform poorly. In contrast, we show that an appropriate first-price auction has nice equilibria in a single-slot ad auction --- all equilibria that satisfy a natural cooperative envy-freen...

  14. Vertical barriers with increased sorption capacities

    Bradl, H.B. [Bilfinger + Berger Bauaktiengesellschaft, Mannheim (Germany)

    1997-12-31

    Vertical barriers are commonly used for the containment of contaminated areas. Due to the very small permeability of the barrier material which is usually in the order of magnitude of 10-10 m/s or less the advective contaminant transport can be more or less neglected. Nevertheless, there will always be a diffusive contaminant transport through the barrier which is caused by the concentration gradient. Investigations have been made to increase the sorption capacity of the barrier material by adding substances such as organoclays, zeolites, inorganic oxides and fly ashes. The contaminants taken into account where heavy metals (Pb) and for organic contaminants Toluole and Phenantrene. The paper presents results of model calculations and experiments. As a result, barrier materials can be designed {open_quotes}tailor-made{close_quotes} depending on the individual contaminant range of each site (e.g. landfills, gasworks etc.). The parameters relevant for construction such as rheological properties, compressive strength and permeability are not affected by the addition of the sorbents.

  15. Vertical barriers with increased sorption capacities

    Vertical barriers are commonly used for the containment of contaminated areas. Due to the very small permeability of the barrier material which is usually in the order of magnitude of 10-10 m/s or less the advective contaminant transport can be more or less neglected. Nevertheless, there will always be a diffusive contaminant transport through the barrier which is caused by the concentration gradient. Investigations have been made to increase the sorption capacity of the barrier material by adding substances such as organoclays, zeolites, inorganic oxides and fly ashes. The contaminants taken into account where heavy metals (Pb) and for organic contaminants Toluole and Phenantrene. The paper presents results of model calculations and experiments. As a result, barrier materials can be designed 'tailor-made' depending on the individual contaminant range of each site (e.g. landfills, gasworks etc.). The parameters relevant for construction such as rheological properties, compressive strength and permeability are not affected by the addition of the sorbents

  16. Creatine transporter (SLC6A8 knock out mice display an increased capacity for in vitro creatine biosynthesis in skeletal muscle

    AaronPaulRussell

    2014-08-01

    Full Text Available The present study aimed to investigate whether skeletal muscle from whole body creatine transporter (CrT; SLC6A8 knockout mice (CrT-/y actually contained creatine (Cr and if so, whether this Cr could result from an up regulation of muscle Cr biosynthesis. Gastrocnemius muscle from CrT-/y and wild type (CrT+/y mice were analysed for ATP, Cr, Cr phosphate (CrP and total Cr (TCr content. Muscle protein and gene expression of the enzymes responsible for Cr biosynthesis L-arginine:glycine amidotransferase (AGAT and guanidinoacetate methyltransferase (GAMT were also determined as were the rates of in vitro Cr biosynthesis. CrT-/y mice muscle contained measurable (22.3 ± 4.3 mmol.kg-1 dry mass, but markedly reduced (P<0.05 TCr levels compared with CrT+/y mice (125.0 ± 3.3 mmol.kg-1 dry mass. AGAT gene and protein expression were higher (~3 fold; P<0.05 in CrT-/y mice muscle, however GAMT gene and protein expression remained unchanged. The in vitro rate of Cr biosynthesis was elevated 1.5 fold (P<0.05 in CrT-/y mice muscle. These data clearly demonstrate that in the absence of CrT protein, skeletal muscle has reduced, but not absent, levels of Cr. This presence of Cr was most likely due to an up regulation of muscle Cr biosynthesis as evidenced by an increased AGAT protein expression and in vitro Cr biosynthesis rates in CrT-/y mice. Of note, the up regulation of Cr biosynthesis in CrT-/y mice muscle was unable to fully restore Cr levels to that found in wild type muscle.

  17. AdS_3: the NHEK generation

    Bena, Iosif; Puhm, Andrea

    2015-01-01

    It was argued in arXiv:1203.4227 that the five-dimensional near-horizon extremal Kerr (NHEK) geometry can be embedded in String Theory as the infrared region of an infinite family of non-supersymmetric geometries that have D1, D5, momentum and KK monopole charges. We show that there exists a method to embed these geometries into asymptotically-AdS_3 x S^3/Z_N solutions, and hence to obtain infinite families of flows whose infrared is NHEK. This indicates that the CFT dual to the NHEK geometry is the IR fixed point of a Renormalization Group flow from a known local UV CFT and opens the door to its explicit construction.

  18. Hadronization at the AdS wall

    We describe hadronization events, using the AdS/CFT Correspondence, which display many of the qualitative features expected in QCD. In particular we study the motion of strings with separating end points in a back-reacted hard wall geometry. The solutions show the development of a linear QCD-like string. The end points oscillate in the absence of string breaking. We introduce string breaking by hand and evolve the new state forward in time to observe the separation of two string segments. A kink associated with this breaking evolves to the end points of the string inducing rho meson production. We explicitly compute the rho meson production at the end point.

  19. AdS backgrounds from black hole horizons

    We utilize the classification of IIB horizons with 5-form flux to present a unified description for the geometry of AdSn, n = 3, 5, 7 solutions. In particular, we show that all such backgrounds can be constructed from eight-dimensional 2-strong Calabi–Yau geometries with torsion which admit some additional isometries. We explore the geometry of AdS3 and AdS5 solutions but we do not find AdS7 solutions. (paper)

  20. ADS National Programmes: Italy

    Following a preliminary design developed in 1998, based on the Energy Amplifier concept proposed by CERN, a first configuration of a lead-bismuth Eutectic cooled Experimental ADS (LBE-XADS) was worked out in the period 1999–2001, under the aegis of MURST, by a group of Italian organizations led by Ansado Nucleare, with the aim of assessing the feasibility of a small sized (80 MWth) ADS. At the end of 1997 a joint effort of ENEA (National Agency for New Technology, Energy and the Environment) and INFN (National Institute for Nuclear Physics) led to the approval of a national programme by MURST (Minister for University and Scientific and Technological Research) named TRASCO (TRAsmutazione SCOrie) aiming at the study of physics and technologies needed to design an ADS for radioactive waste transmutation. The programme consisted of research subprogrammes on accelerator, neutronics, thermalhydraulics analysis, beam window technology, and material technology and compatibility with Pb and Pb-Bi. At now, most of the activities in support to the ADS development carried out at national level are part of EU-funded Projects. These activities are complemented by the programme agreement (AdP -Accordo di programma), signed between ENEA and the Ministry of Economic Development, which provides in general a range of activities aimed at the development of sustainable nuclear fission systems. Several universities and the national industry are involved, besides ENEA, in the activities

  1. 03. Disruption Management in PassengerTransportation - from Air to Tracks

    Clausen, Jens

    2007-01-01

    Over the last 10 years there has been a tremendous growth in air transportation of passengers. Both airports and airspace are close to saturation with respect to capacity, leading to delays caused by disruptions. At the same time the amount of vehicular traffic around and in all larger cities of the world has show a dramatic increase as well. Public transportation by e.g. rail has come into focus, and hence also the service level provided by suppliers ad public transportatio...

  2. Value Adding Management

    Jensen, Per Anker; Katchamart, Akarapong

    2011-01-01

    Purpose: To investigate how Facilities Management (FM) can add value and develop a management concept that can assist facilities managers in implementing value adding strategies and practices. Theory: The study is based on the management model for FM included in the European FM standards, recent...... impacts and strategic importance of FM for organisations and can be a practical tool for facilities managers in implementing value adding strategies and practices....... investigated, tested and discussed based on a case study of an international corporation. Findings: The study shows that the management model for FM creates a relevant starting point but also that stakeholder and relationship management is an essential aspect of Value Adding Management. The case study confirms...

  3. ADS National Programmes: China

    In China the conceptual study of an ADS concept which lasted for about five years ended in 1999. As one project of the National Basic Research Programme of China (973 Programme) in energy domain, which is sponsored by the China Ministry of Science and Technology (MOST), a five year programme of fundamental research of ADS physics and related technology was launched in 2000 and passed national review at the end of 2005. From 2007, another five year 973 Programme Key Technology Research of Accelerator Driven Subcritical System for Nuclear waste Transmutation started. The research activities were focused on HPPA physics and technology, reactor physics of external source driven subcritical assembly, nuclear data base and material study. For HPPA, a high current injector consisting of an ECR ion source, LEBT and an RFQ accelerating structure of 3.5 MeV has been built and were being improved. In reactor physics study, a series of neutron multiplication experimental study has been carrying out. The VENUS I facility has been constructed as the basic experimental platform for neutronics study in ADS blanket. VENUS I a zero power subcritical neutron multiplying assembly driven by external neutron produced by a pulsed neutron generator or 252Cf neutron source. The theoretical, experimental and simulation studies on nuclear data, material properties and nuclear fuel circulation related to ADS are carried out in order to provide the database for ADS system analysis. China Institute of Atomic Energy (CIAE), Institute of High Energy Physics (IHEP) and other Chinese institutes carried out the MOST project together. Besides CIAE, China Academy of Science (CAS) pays more and more attention to Advanced Nuclear Fuel Cycles (ANFC). A large programme of ANFC, including ADS and Th based nuclear fuel cycle, has been launched by CAS

  4. Dynamic ad hoc networks

    Rashvand, Habib

    2013-01-01

    Motivated by the exciting new application paradigm of using amalgamated technologies of the Internet and wireless, the next generation communication networks (also called 'ubiquitous', 'complex' and 'unstructured' networking) are changing the way we develop and apply our future systems and services at home and on local, national and global scales. Whatever the interconnection - a WiMAX enabled networked mobile vehicle, MEMS or nanotechnology enabled distributed sensor systems, Vehicular Ad hoc Networking (VANET) or Mobile Ad hoc Networking (MANET) - all can be classified under new networking s

  5. ADS National Programmes: Belgium

    The Belgian activities in the field of Accelerator Driven Systems (ADS) are mainly related to the MYRRHA project development. MYRRHA is an accelerator driven, multi purpose fast neutron spectrum facility for R&D, cooled by a lead-bismuth eutectic. SCK•CEN has started the MYRRHA project as a national programme with several national & international bilateral collaboration agreements; the project has now evolved as an European integrated project in the frame of the IPEUROTRANS (European Commission, Sixth Framework Programme). The MYRRHA ‘Draft-2’ predesign file (completed in the early 2005) has been proposed to the partners as a basis for the XT-ADS machine. After a detailed investigation of potential alternatives, the MYRRHA concept (for the subcritical core, the primary coolant system, the accommodation of experimental rigs, the reactor vessel and the spallation target) has been kept with some modifications to achieve the XT-ADS objectives. The most recent version of the XT-ADS design was presented in the 2007 TWG meeting

  6. Capacity Analysis on Multi-Lane Roundabouts: An Evaluation With Highway Capacity Manual 2010 Capacity Model

    Melike Ersoy

    2014-06-01

    Full Text Available In this study, capacity estimations with the incorporation of Highway Capacity Manual (HCM 2010 method are evaluated. Parameter based sensitivity analysis on calculations with the new HCM formula and a comparative evaluation of the new methodology with two most common capacity analysis methods, i.e., the method of critical gap acceptance and the method of regression analysis, are performed. Maximum and minimum headway intervals of follow up time and critical gap parameters are alternated within the sensitivity analysis. The Transport Research Laboratory formula for regression and Australian formula for gap acceptance method are considered in comparison. Relative comparisons of predictions on capacity by HCM2010 method, regression analysis and gap acceptance method are presented considering field data obtained by observations at two roundabouts in Izmir, Turkey. The results of the study show that the HCM2010 formula led to lower capacity estimates than regression analysis and higher estimates than the gap acceptance method. Regarding the real capacity observations under high circulating flow-rates the HCM2010 method yielded to more appropriate results than the regression method. In addition to comparisons, studies on the sensitivity analysis show that entry capacity estimates possess sharper changes as smaller follow up headways are accepted.

  7. ADS specific accelerator developments: Status in Japan

    In Japan, JAEA proposes an ADS which consists of a high power proton LINAC, a spallation target of lead-bismuth eutectic (LBE) and a subcritical core. In this proposal, the energy and beam power of the high power proton LINAC are 1.5 GeV and 20–30 MW, respectively. Other specifications of the high power proton linac are described in [4.28]. An important technical aspect that is considered in the JAEA work is the negative impact of very frequent beam trips as experienced in existing intense accelerator facilities. Frequent beam trips cause thermal fatigue problems for ADS components materials, leading to degradation of their structural integrity and reduction of their lifetime. They can also badly erode the availability or the capacity of ADS, resulting in poor economics. In the development of accelerators for ADS, it is vitally important to establish the technologies to achieve a very high degree of reliability. On the other hand, JAEA considers that it is also important in the development of ADS to design structural components to withstand possible thermal fatigues and a power conversion system less sensitive to beam trips. The purpose of the JAEA study is the comparison of beam trip frequencies between requirement from ADS transient analyses and estimation from current experimental data of accelerators

  8. 49 CFR 1572.109 - Mental capacity.

    2010-10-01

    ... intelligence, mental illness, incompetence, condition, or disease, is a danger to himself or herself or to... 49 Transportation 9 2010-10-01 2010-10-01 false Mental capacity. 1572.109 Section 1572.109... ASSESSMENTS Standards for Security Threat Assessments § 1572.109 Mental capacity. (a) An applicant has...

  9. ADS National Programmes: Japan

    In Japan, the research and development (R&D) activities on partitioning and transmutation (P&T) technology had been promoted under the OMEGA programme since 1988. The main institutes involved in these activities were the Japan Atomic Energy Research Institute (JAERI), the Japan Nuclear Cycle Development Institute (JNC), and the Central Research Institute of Electric Power Industry (CRIEPI). Among these institutes, JAERI had mainly conducted the R&D on ADS. In 1999 and 2000, the Atomic Energy Commission (AEC) of Japan implemented the check and review (C&R) on the P&T technology, and the ADS was considered as one of candidates for transmutation systems together with fast reactors. In 2005, JAERI and JNC were merged and the Japan Atomic Energy Agency (JAEA) was established. In JAEA, the R&D activities on both ADS and fast reactors have been continued. In August, 2008, the AEC of Japan launched the Technical Subcommittee on P&T Technology under the Advisory Committee on R&D, and conducted the discussion about the current state of the art concerning P&T technology in Japan and the future R&D programme. The Subcommittee issued the final report in April, 2009. The final report covered the impact of the P&T technology, the state of the art of the technology, evaluation on the progress of the R&D, and the recommendations of the future R&D. As the basic policy on the P&T technology, the report stated that the R&D should not aim at only the improvement of the P&T performance, but at the achievement of the requirements for whole performance of nuclear power generation. This means that the performance of the Double strata fuel cycle concept should be evaluated from viewpoints of safety, economy, environmental friendliness, saving resource, and non-proliferation of the first stratum as well as those of the second stratum. The Double strata concept, therefore, should be studied as a part of the whole nuclear system both in the transient phase of LWR to FBR and the equilibrium

  10. Nuclear transport - The regulatory dimension

    The benefits that the peaceful applications of nuclear energy have brought to society are due in no small part to industry's capacity to transport radioactive materials safely, efficiently and reliably. The nuclear transport industry has a vital role in realising a fundamental objective of the International Atomic Energy Agency (IAEA) as stated in its statute to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world. The context in which transports currently take place is complex, and rapidly changing. In many respects transport is being viewed as an integral market issue and not a subsidiary concern. The availability of carriers drives routing decisions and changes in material flows necessitate new approaches to packaging and transport scenarios. Pressures on the transport sector are not without serious consequences; they can cause delays and in some cases cancellation of planned movements. Complex routings and the necessary use of chartered carriers can push up costs and work against cost efficiency. Since the events of 11 September 2001 the security of nuclear transports has contributed an added dimension to how transports take place. Transports of radioactive material have an outstanding safety record, indeed the transport of such materials could be regarded as a model for the transport of other classes of dangerous goods. This safety record is achieved by two inter-related factors. It is due primarily to well founded regulations developed by such key intergovernmental organisations as the IAEA, with the essential contributions of the member states who participate in the implementation of regulations and the review process. It is due also to the professionalism of those in the industry. There is a necessary synergy between the two - between the regulators whose task it is to make and to enforce the rules for safe, efficient and reliable transport and those whose job it is to transport within the rules. It

  11. High capacity carrier ethernet transport networks

    Rasmussen, Anders; Zhang, Jiang; Yu, Hao; Fu, Rong; Ruepp, Sarah Renée; Wessing, Henrik; Berger, Michael Stübert

    2009-01-01

    technology, making the use of Ethernet as a convergence layer for Next Generation Networks a distinct possibility. Triple Play services, in particular IPTV, are expected to be a main drivers for carrier Ethernet, however, a number of challenges must be addressed including QoS enabled control plane, enhanced...... OAM functions, survivability and the increased bandwidth requirements of carrier class systems. This article provides an overview of PBB-TE and T-MPLS and demonstrates how IPTV services can be realized in the framework of Carrier Ethernet. In addition we provide a case study on performing bit error...

  12. Management job ads

    Holmgreen, Lise-Lotte

    2014-01-01

    jobs by discursively constructing job ads that appeal to both sexes. This argument is part of the broader field of corporate social responsibility, corporate citizenship, and stakeholder management, which involves discussions of the obligations of corporations to acknowledge and mitigate the......The article asks whether it is not the responsibility of corporations to address the issue of women being underrepresented in Danish management jobs. In other words, it is argued that corporations should be encouraged to engage more actively in the recruitment of both men and women for management...... increasingly widespread impact that their activities have on communities and social structures. The article emphasises the need for more active engagement on the part of corporations by analysing the discursive construction of preferred candidates in a small sample of Danish management job ads. By means of...

  13. Adding linear orders

    Shelah, Saharon

    2011-01-01

    We address the following question: Can we expand an NIP theory by adding a linear order such that the expansion is still NIP? Easily, if acl(A)=A for all A, then this is true. Otherwise, we give counterexamples. More precisely, there is a totally categorical theory for which every expansion by a linear order has IP. There is also an \\omega-stable NDOP theory for which every expansion by a linear order interprets bounded arithmetic.

  14. ADS National Programmes: France

    Studies related to nuclear reactors and radioactive waste started at the French National Centre for Scientific research, CNRS, as a result of the French law on radioactive waste that was published in 1991. They were initially organized around the programme PACE (Physique pour l’Aval du Cycle Electronucléaire = physics of the back end of the nuclear fuel cycle), which became PACEN (Physique pour l’Aval du Cycle et production d’Energie Nucléaire = Physics of the back end of the nuclear fuel cycle and production of nuclear energy) in 2006. Research on accelerator driven systems was from the beginning part of this programme. This research is mainly funded by the National Institute for Nuclear end Particle Physics (IN2P3) of CNRS and within the EURATOM European programmes (FP5, 6 and 7). The programme took place in several stages, and covered various scientific fields, benefitting from expertise of CNRS in the field. More specifically, it aimed and still aims to: – Test and verify the feasibility and design of the ADS concept, in terms of neutronics, physics of materials, design of the accelerator and tests of its prototypical components that have been built (or are at present under construction); – Measure and-or improve nuclear data related to radioactive waste transmutation. Today, most of the activities in support to ADS development carried out by CNRS focus on accelerator developments, GUINEVERE (Generator of Uninterrupted Intense NEutron at the lead VEnus REactor) experiment, ADS core studies, deployment scenarios and nuclear data measurements. The CEA R&D programmes on ADS are mainly focused on the European project EUROTRANS of the 6th Framework programme (2005–2010) and continued in the FREYA project of the 7th Framework Programme

  15. AdS 3-manifolds and Higgs bundles

    Alessandrini, Daniele; Li, Qiongling

    2015-01-01

    In this paper we investigate the relationships between closed AdS 3-manifolds and Higgs bundles. We have a new way to construct AdS structures that allows us to see many of their properties explicitly, for example we can recover the very recent formula by Tholozan for the volumes. We also find...

  16. Temporal analysis of the connectivity and potential transport capacity of sediments in semiarid meso-basin, CE, Brazil. = Análise temporal da conectividade e da capacidade de transporte potencial de sedimentos em meso-bacia semiárida, CE, Brasil.

    José Wellington Batista Lopes

    2013-08-01

    Full Text Available The transfer of energy and matter between two topographic units comprise the connectivity process. The identification of the connectivity patterns in the catchments allow to represent the linking degree between sediment producing areas and network drainage. The aim of this study was to evaluate spatial and temporal connectivity and estimate the potential capacity of sediment transport on a meso-semiarid Basin. The study area comprises the Representative Madalena Basin (RMB with area 124 km², located at federal state from Ceara, Brazil. The assessing the connectivity was done by using the quantitative index. The determination of peak discharge was by the method NRCS (Natural Resouces Conservation Service and the transport capacity (CT, t ha-1 yr-1 was calculated by the method of Morgan (2001. The results showed that: the connectivity potential index was not linearity, but a possible spatial distribution pattern of alternating between producing and receiving areas. The use and occupation of land is determinant in the spatial variation of peak flows; transportation capacity concerns associated with potential connectivity provides best estimates of erosion in the basin; in both models used, the use and occupation of soil was crucial in the results. = A transferência de energia e matéria entre duas unidades topográficas compreende o processo deconectividade. A identificação dos padrões de conectividade em uma bacia hidrográfica permite representar o grau de ligação entre áreas produtoras de sedimentos e a rede de drenagem. Objetivou-se com esta pesquisa analisar a conectividade espaço-temporal e estimar a capacidade potencial de transporte de sedimentos em uma meso-baciasemiárida. A área foco do estudo compreende a Bacia Representativa de Madalena (BRM com área de 124 km², localizada no Estado do Ceará, Brasil. Foram avaliadas as seguintes variáveis: conectividade, o pico de descarga e a capacidade de transporte de escoamento da

  17. Evaporation of large black holes in AdS

    The AdS/CFT correspondence offers a new perspective on the long-standing black hole information paradox. However, to be able to use the available gauge/gravity machinery one is forced to consider so-called 'large' black holes in AdS, and these objects are thermodynamically stable - they do not evaporate. We describe a simple toy model that allows large AdS black holes to decay, by coupling the emitted radiation to an external scalar field propagating in an auxiliary space. This effectively changes the properties of the boundary of AdS, making it partly absorbing. We demonstrate that the evaporation process never ceases by explicitly presenting (a) the transmission coefficient for a wave scattering from the bulk into auxiliary space and (b) the greybody factor for a black 3-brane in an AdS background. Therefore, the model provides an interesting framework to address the information paradox using AdS/CFT techniques.

  18. The effect of Ad

    李小艳

    2010-01-01

    There is the trend that now people appreciate those who are slim and regard slim even thin people beautiful. The thinner a person is, the more beautiful. Women, born to pursuit beauty, try various means to follow the trend. We all watch TV, and find a lot of advertisements on diet. The effect of them is tremendous. We all know the fact that it is not at all the better mouse trap will catch mouse. The sales methods are more important. If an advertisement is very interesting and seemingly effective, people will be lured by the ad and then try some of the products.

  19. Eating ad Libitum

    Hillersdal, Line

    in the context of the 'ad libitum meal'. The analytical interest is thus what kind of eaters and bodies are enacted in the meal test and what ideas of prevention and treatment are embedded in their standards. Drawing from ongoing empirical work among Danish obesity researchers performing scientific...... producing an eater who: ”shouldn't restrain herself”. Practices of food and eating in the test meal I suggest, will allow us to tackle reductionism by showing the complex cultural context shaping clinical intervention....

  20. Ad hoc mobile wireless networks principles, protocols, and applications

    Sarkar, Subir Kumar

    2013-01-01

    The military, the research community, emergency services, and industrial environments all rely on ad hoc mobile wireless networks because of their simple infrastructure and minimal central administration. Now in its second edition, Ad Hoc Mobile Wireless Networks: Principles, Protocols, and Applications explains the concepts, mechanism, design, and performance of these highly valued systems. Following an overview of wireless network fundamentals, the book explores MAC layer, routing, multicast, and transport layer protocols for ad hoc mobile wireless networks. Next, it examines quality of serv

  1. Vaccination with Ad5 vectors expands Ad5-specific CD8 T cells without altering memory phenotype or functionality.

    Natalie A Hutnick

    Full Text Available BACKGROUND: Adenoviral (Ad vaccine vectors represent both a vehicle to present a novel antigen to the immune system as well as restimulation of immune responses against the Ad vector itself. To what degree Ad-specific CD8(+ T cells are restimulated by Ad vector vaccination is unclear, although such knowledge would be important as vector-specific CD8(+ T cell expansion could potentially further limit Ad vaccine efficacy beyond Ad-specific neutralizing antibody alone. METHODOLOGY/PRINCIPAL FINDINGS: Here we addressed this issue by measuring human Adenovirus serotype 5 (Ad5-specific CD8(+ T cells in recipients of the Merck Ad5 HIV-1 vaccine vector before, during, and after vaccination by multicolor flow cytometry. Ad5-specific CD8(+ T-cells were detectable in 95% of subjects prior to vaccination, and displayed primarily an effector-type functional profile and phenotype. Peripheral blood Ad5-specific CD8(+ T-cell numbers expanded after Ad5-HIV vaccination in all subjects, but differential expansion kinetics were noted in some baseline Ad5-neutralizing antibody (Ad5 nAb seronegative subjects compared to baseline Ad5 nAb seropositive subjects. However, in neither group did vaccination alter polyfunctionality, mucosal targeting marker expression, or memory phenotype of Ad5-specific CD8(+ T-cells. CONCLUSIONS: These data indicate that repeat Ad5-vector administration in humans expands Ad5-specific CD8(+ T-cells without overtly affecting their functional capacity or phenotypic properties. This is a secondary analysis of samples collected during the 016 trial. Results of the Merck 016 trial safety and immunogenicity have been previously published in the journal of clinical infectious diseases [1]. TRIAL REGISTRATION: ClinicalTrials.gov NCT00849680[http://www.clinicaltrials.gov/show/NCT00849680].

  2. Ehrenfest's scheme and thermodynamic geometry in Born-Infeld AdS black holes

    Lala, Arindam; Roychowdhury, Dibakar

    2012-10-01

    In this paper, we analyze the phase transition phenomena in Born-Infeld anti-de Sitter (BI AdS) black holes using Ehrenfest’s scheme of standard thermodynamics. The critical points are marked by the divergences in the heat capacity. In order to investigate the nature of the phase transition, we analytically check both Ehrenfest equations near the critical points. Our analysis reveals that this is indeed a second order phase transition. Finally, we analyze the nature of the phase transition using the state space geometry approach. This is found to be compatible with Ehrenfest’s scheme.

  3. Ehrenfest's scheme and thermodynamic geometry in Born-Infeld AdS black holes

    Lala, Arindam

    2011-01-01

    In this paper we analyze the phase transition phenomena in Born-Infeld AdS black holes using Ehrenfest's scheme of standard thermodynamics. The critical points are marked by the divergences in the heat capacity. In order to investigate the nature of the phase transition, we analytically check both the Ehrenfest's equations near the critical points. Our analysis reveals that this is indeed a second order phase transition. Finally, we analyze the nature of the phase transition using state space geometry approach. This is found to be compatible with the Ehrenfest's scheme.

  4. Capacity Expansion for Random Exponential Demand Growth with Lead Times

    Ryan, Sarah M.

    2004-01-01

    The combination of demand uncertainty and a lead time for adding capacity creates the risk of capacity shortage during the lead time. We formulate a model of capacity expansion for uncertain exponential demand growth and deterministic expansion lead times when there is an obligation to provide a specified level of service. The service level, defined in terms of the ratio of expected lead-time shortage to installed capacity, is guaranteed by timing each expansion to begin when demand reaches a...

  5. Killing spinors and supersymmetry on AdS

    In this paper we construct several supersymmetric theories on AdS5 background. We discuss the proper definition of the Killing equation for the symplectic Majorana spinors required in AdS5 supersymmetric theories. We find that the symplectic Killing spinor equation involves a matrix M in the USp(2N) indices whose role was not recognized previously. Using the correct Killing spinors we explicitly confirm that the particle masses in the constructed theories agree with the predictions of the AdS/CFT correspondence. Finally, we establish correct O(d - 1,2) isometry transformations required to keep the Lagrangian invariant on AdSd

  6. Dirac operator on fuzzy AdS2

    In this article we construct the chirality and Dirac operators on fuzzy AdS2. We also derive the discrete spectrum of the Dirac operator which is important in the study of the spectral triple associated to AdS2. It is shown that the degeneracy of the spectrum present in the commutative AdS2 is lifted in the noncommutative case. The way we construct the chirality operator is suggestive of how to introduce the projector operators of the corresponding projective modules on this space. (author)

  7. Dirac Operator on Noncommutative AdS_2

    Fakhri, H

    2003-01-01

    In this article we construct the chirality and Dirac operators on noncommutative AdS_2. We also derive the discrete spectrum of the Dirac operator which is important in the study of the spectral triple associated with AdS_2. It is shown that the degeneracy of the spectrum present in the commutative AdS_2 is lifted in the noncommutative case. The way we construct the chirality operator is suggestive of how to introduce the projector operators of the corresponding projective modules on this space.

  8. Dirac operator on fuzzy AdS2

    Fakhri, Hossein; Imaanpur, Ali

    2003-03-01

    In this article we construct the chirality and Dirac operators on noncommutative AdS2. We also derive the discrete spectrum of the Dirac operator which is important in the study of the spectral triple associated to AdS2. It is shown that the degeneracy of the spectrum present in the commutative AdS2 is lifted in the noncommutative case. The way we construct the chirality operator is suggestive of how to introduce the projector operators of the corresponding projective modules on this space.

  9. Dirac Operator on Fuzzy AdS_2

    H. Fakhri; Imaanpur, A.

    2003-01-01

    In this article we construct the chirality and Dirac operators on noncommutative AdS_2. We also derive the discrete spectrum of the Dirac operator which is important in the study of the spectral triple associated with AdS_2. It is shown that the degeneracy of the spectrum present in the commutative AdS_2 is lifted in the noncommutative case. The way we construct the chirality operator is suggestive of how to introduce the projector operators of the corresponding projective modules on this space.

  10. Radius-dependent gauge unification in AdS5

    Choi, Kiwoon; Kim, Hyung Do; Kim, Ian-Woo

    2002-01-01

    We examine the relation of the 4-dimensional low energy coupling of bulk gauge boson in a slice of AdS5 to the 5-dimensional fundamental couplings as a function of the orbifold radius R. This allows us to address the gauge coupling unification in AdS5 by means of the radius running as well as the conventional momentum running. We then compute the radius dependence of 1-loop low energy couplings in generic AdS5 theory with 4-dimensional supersymmetry, and discuss the low energy predictions whe...

  11. Open Strings on AdS_2 Branes

    Lee, Peter; Ooguri, Hirosi; Park, Jongwon; Tannenhauser, Jonathan

    2001-01-01

    We study the spectrum of open strings on AdS_2 branes in AdS_3 in an NS-NS background, using the SL(2,R) WZW model. When the brane carries no fundamental string charge, the open string spectrum is the holomorphic square root of the spectrum of closed strings in AdS_3. It contains short and long strings, and is invariant under spectral flow. When the brane carries fundamental string charge, the open string spectrum again contains short and long strings in all winding sectors. However, branes w...

  12. Thermodynamics of Asymptotically Locally AdS Spacetimes

    Papadimitriou, I; Papadimitriou, Ioannis; Skenderis, Kostas

    2005-01-01

    We formulate the variational problem for AdS gravity with Dirichlet boundary conditions and demonstrate that the covariant counterterms are necessary to make the variational problem well-posed. The holographic charges associated with asymptotic symmetries are then rederived via Noether's theorem and `covariant phase space' techniques. This allows us to prove the first law of black hole mechanics for general asymptotically locally AdS black hole spacetimes. We illustrate our discussion by computing the conserved charges and verifying the first law for the four dimensional Kerr-Newman-AdS and the five dimensional Kerr-AdS black holes.

  13. Symmetric, coherent, Choquet capacities

    Kadane, Joseph B.; Wasserman, Larry

    1996-01-01

    Choquet capacities are a generalization of probability measures that arise in robustness, decision theory and game theory. Many capacities that arise in robustness are symmetric or can be transformed into symmetric capacities. We characterize the extreme points of the set of upper distribution functions corresponding to coherent, symmetric Choquet capacities on [0, 1]. We also show that the set of 2-alternating capacities is a simplex and we give a Choquet representation of this set.

  14. Conical singularities in AdS space time

    Full text: In recent years, the study of conformal gauge theories from 10-D has been motivated by the AdSd+1/CFTd correspondence, first conjectured by J. Maldacena. The aim of this work is to consider the d = 4 case by analysing the configuration of the N coincident D3 branes. In this context, the work shows that there is a duality between type IIB string theory in AdS5 x S5 and N = 4 SU(N) Super Yang-Mills Theory in the IR. The AdS5/CFT4 correspondence brought also new approaches to the strong coupling problem in QCD. Nowadays, there is a whole line of works that focus on the low dimensional correspondence AdS4/CFT3, like the application to graphene and topological insulators, and the AdS3/CFT2 correspondence, related with the entanglement entropy. In this work, we consider the vortex configuration solution to the AdS4 and AdS3 space-time. The most important motivation is to discuss the boundary theory resulting from these solutions. We have examined a straightforward approach to a holographic computation of the graphene and entanglement entropy in the presence of the conical singularity. After this analysis, we consider the scalar field in the bulk in the presence of this metrics and work out the compactification modes. Taking the holographic point of view, we study and discuss the resulting Green function. (author)

  15. 营改增对物流运输业影响及对策研究%Influence and Countermeasures“Replace the Business Tax with a Value-Added Tax” on the Logistics Transportation

    游道柱; 葛拥军; 翁志梅

    2014-01-01

    Analysis changes of enterprise tax burden after value added tax through sampling surveys ,on the basis of above , put forward the Countermeasures of logistics enterprises and policy suggestions.%文中通过抽样调研分析“营改增”后物流运输企业税负变化情况,提出物流企业应对“营改增”的对策,并在此基础上提出政策建议。

  16. Thermodynamics of large AdS black holes

    We consider leading order quantum corrections to the geometry of large AdS black holes in a spherical reduction of four-dimensional Einstein gravity with negative cosmological constant. The Hawking temperature grows without bound with increasing black hole mass, yet the semiclassical back-reaction on the geometry is relatively mild, indicating that observers in free fall outside a large AdS black hole never see thermal radiation at the Hawking temperature. The positive specific heat of large AdS black holes is a statement about the dual gauge theory rather than an observable property on the gravity side. Implications for string thermodynamics with an AdS infrared regulator are briefly discussed

  17. Supersymmetric Kaluza-Klein reductions of AdS backgrounds

    Figueroa-O'Farrill, J M; Farrill, Jos\\'e Figueroa-O'; Sim\\'on, Joan

    2004-01-01

    This paper contains a classification of smooth Kaluza--Klein reductions (by one-parameter subgroups) of the maximally supersymmetric anti de Sitter backgrounds of supergravity theories. We present a classification of one-parameter subgroups of isometries of anti de Sitter spaces, discuss the causal properties of their orbits on these manifolds, and discuss their action on the space of Killing spinors. We analyse the problem of which quotients admit a spin structure. We then apply these results to write down the list of smooth everywhere spacelike supersymmetric quotients of AdS_3 x S^3 (x R^4), AdS_4 x S^7, AdS_5 x S^5 and AdS_7 x S^4, and the fraction of supersymmetry preserved by each quotient. The results are summarised in tables which should be useful on their own. The paper also includes a discussion of supersymmetry of singular quotients.

  18. Managing the market risk in pipeline capacity positions

    Managing the risk involved in adding new pipeline capacity was explored in this presentation. Topics discussed included: (1) pipeline capacity positions as basis swaps, (2) physical capacity versus basis transactions, (3) managing the market price risk in a capacity position, and (4) sharing of pipeline market risk. Pipeline owners were advised to recognize that pipeline capacity carries significant market price risk, that basis markets can sometimes be more volatile than outright markets, and to treat physical capacity market risk the same way as one would treat a financial basis position. 2 figs

  19. Chaos and hydrodynamics near AdS$_2$

    Jensen, Kristan

    2016-01-01

    We revisit AdS$_2$ holography with the Sachdev-Ye-Kitaev models in mind. Our main result is to rewrite a generic theory of gravity near an AdS$_2$ throat as a novel hydrodynamics coupled to the correlation functions of a conformal quantum mechanics. This gives a prescription for the computation of $n$-point functions in the dual quantum mechanics. We thereby find that the dual is maximally chaotic.

  20. Minisuperspace limit of the AdS3 WZNW model

    Ribault, Sylvain

    2009-01-01

    We derive the three-point function of the AdS3 WZNW model in the minisuperspace limit by Wick rotation from the H3+ model. The result is expressed in terms of Clebsch-Gordan coefficients of the Lie algebra sl(2,R). We also introduce a covariant basis of functions on AdS3, which can be interpreted as bulk-boundary propagators.

  1. ADS National Programmes: Belarus

    The Belarus activities in the field of Accelerator Driven Systems (ADS) are mainly related to the investigations performed at the subcritical facility YALINA. Yalina is a zero power subcritical facility to study neutronics of ADS and the transmutation reaction rates. The first assembly YALINA-T was put into operation in 2000. YALINA-T is a multiplying system (kmax<0.98), located inside a graphite reflector of parallelepiped configuration that is arranged of high purity reactor graphite blocks. The core of the assembly is of parallelepiped configuration too and consists of bare polyethylene subassemblies where fuel rods of EK-10 type (UO2 of 10% enrichment by U235) are located. At the core center a neutron producing Pb target is located that reminds fuel subassembly by shape and size. Graphite reflector is covered from outside by Cd. At the distances R=50 mm, 100 mm, 150 mm from the core center three experimental channels (D=25 mm) are situated for location of samples of radioactive targets and various detectors for measurement of neutron flux density functionals. For the same purpose two axial channels (D=25 mm) are located in graphite reflector at the distances 250 mm and 358 mm; by Z=H/2 one more radial channel (D=25 mm) is located. YALINA-B core is arranged of rectangular parallelepipeds too. The fast (booster) zone consists of lead subassemblies, the thermal one of polyethylene subassemblies. Central part of the booster zone, containing highly enriched (90%) metallic uranium fuel and Pb target is encased into a separate stainless steel frame. The absorber zone is located at the outer boundary of the booster zone. It consists of inner layer of rods with metallic natural uranium fixed in lead blocks, as in the previous cases, and of an outer layer of rods filled by boron carbide powder, B4C. Boron carbide rods are located in the same lattice as the uranium fuel pins in the booster zone with pin pitch 16.00 mm. This absorber zone enables fast neutrons to

  2. Discrimination in Online Ad Delivery

    Sweeney, Latanya

    2013-01-01

    A Google search for a person's name, such as "Trevon Jones", may yield a personalized ad for public records about Trevon that may be neutral, such as "Looking for Trevon Jones?", or may be suggestive of an arrest record, such as "Trevon Jones, Arrested?". This writing investigates the delivery of these kinds of ads by Google AdSense using a sample of racially associated names and finds statistically significant discrimination in ad delivery based on searches of 2184 racially associated person...

  3. Multicast Routing Protocols in Mobile Ad Hoc Networks: A Comparative Survey and Taxonomy

    Badarneh OsamahS; Kadoch Michel

    2009-01-01

    Abstract Multicasting plays a crucial role in many applications of mobile ad hoc networks (MANETs). It can significantly improve the performance of these networks, the channel capacity (in mobile ad hoc networks, especially single-channel ones, capacity is a more appropriate term than bandwidth, capacity is measured in bits/s and bandwidth in Hz) and battery power of which are limited. In the past couple of years, a number of multicast routing protocols have been proposed. In spite of being d...

  4. Complexity Growth for AdS Black Holes

    Cai, Rong-Gen; Wang, Shao-Jiang; Yang, Run-Qiu; Peng, Rong-Hui

    2016-01-01

    We further investigate the Complexity-Action (CA) duality conjecture for stationary anti de-Sitter (AdS) black holes and derive some exact results for the growth rate of action within Wheeler-DeWitt (WDW) patch at late time approximation, which is dual to the growth rate of quantum complexity of holographic state. Based on the results from the general $D$-dimensional Reissner-Nordstr\\"{o}m (RN)-AdS black hole, rotating/charged Ba\\~{n}ados-Teitelboim-Zanelli (BTZ) black hole, Kerr-AdS black hole and charged Gauss-Bonnet-AdS black hole, we present a new complexity bound but leave unchanged the conjecture that the stationary AdS black hole in Einstein gravity is the fastest computer in nature.

  5. Constructing the AdS dual of a Fermi liquid: AdS Black holes with Dirac hair

    \\vCubrović, Mihailo; Schalm, Koenraad

    2010-01-01

    We provide new evidence that the holographic dual to a strongly coupled charged Fermi Liquid has a non-zero fermion density in the bulk. We show that the pole-strength of the stable quasiparticle characterizing the Fermi surface is encoded in the spatially averaged AdS probability density of a single normalizable fermion wavefunction in AdS. Recalling Migdal's theorem which relates the pole strength to the Fermi-Dirac characteristic discontinuity in the number density at $\\ome_F$, we conclude that the AdS dual of a Fermi liquid is described by occupied on-shell fermionic modes in AdS. Encoding the occupied levels in the total probability density of the fermion field directly, we show that an AdS Reissner-Nordstr\\"{o}m black hole in a theory with charged fermions has a critical temperature, at which the system undergoes a first-order transition to a black hole with a non-vanishing profile for the bulk fermion field. Thermodynamics and spectral analysis confirm that the solution with non-zero AdS fermion-profil...

  6. Discontinuous symplectic capacities

    Zehmisch, K.; Ziltener, F.J.

    2014-01-01

    We show that the spherical capacity is discontinuous on a smooth family of ellipsoidal shells. Moreover, we prove that the shell capacity is discontinuous on a family of open sets with smooth connected boundaries.

  7. Total iron binding capacity

    ... page: //medlineplus.gov/ency/article/003489.htm Total iron binding capacity To use the sharing features on this page, please enable JavaScript. Total iron binding capacity (TIBC) is a blood test to ...

  8. AdS-Carroll Branes

    Clark, T E

    2016-01-01

    Coset methods are used to determine the action of a co-dimension one brane (domain wall) embedded in (d+1)-dimensional AdS space in the Carroll limit in which the speed of light goes to zero. The action is invariant under the non-linearly realized symmetries of the AdS-Carroll spacetime. The Nambu-Goldstone field exhibits a static spatial distribution for the brane with a time varying momentum density related to the brane's spatial shape as well as the AdS-C geometry. The AdS-C vector field dual theory is obtained.

  9. PAYMENT CAPACITY SENSITIVITY FACTORS

    Daniel BRÎNDESCU – OLARIU

    2014-11-01

    The results of the study facilitate the determination and classification of the main sensitivity factors for the payment capacity at sample level, the establishment of general benchmarks for the payment capacity (as no such benchmarks currently exist in the Romanian literature and the identification of the mechanisms through which the variation of different factors impacts the payment capacity.

  10. CDMA systems capacity engineering

    Kim, Kiseon

    2004-01-01

    This new hands-on resource tackles capacity planning and engineering issues that are crucial to optimizing wireless communication systems performance. Going beyond the system physical level and investigating CDMA system capacity at the service level, this volume is the single-source for engineering and analyzing systems capacity and resources.

  11. Detailed ultraviolet asymptotics for AdS scalar field perturbations

    Evnin, Oleg

    2016-01-01

    We present a range of methods suitable for accurate evaluation of the leading asymptotics for integrals of products of Jacobi polynomials in limits when the degrees of some or all polynomials inside the integral become large. The structures in question have recently emerged in the context of effective descriptions of small amplitude perturbations in anti-de Sitter (AdS) spacetime. The limit of high degree polynomials corresponds in this situation to effective interactions involving extreme short-wavelength modes, whose dynamics is crucial for the turbulent instabilities that determine the ultimate fate of small AdS perturbations. We explicitly apply the relevant asymptotic techniques to the case of a self-interacting probe scalar field in AdS and extract a detailed form of the leading large degree behavior, including closed form analytic expressions for the numerical coefficients appearing in the asymptotics.

  12. Logarithmic AdS waves and Zwei-Dreibein gravity

    We show that the parameter space of Zwei-Dreibein Gravity (ZDG) in AdS3 exhibits critical points, where massive graviton modes coincide with pure gauge modes and new ‘logarithmic’ modes appear, similar to what happens in New Massive Gravity. The existence of critical points is shown both at the linearized level, as well as by finding AdS wave solutions of the full non-linear theory, that behave as logarithmic modes towards the AdS boundary. In order to find these solutions explicitly, we give a reformulation of ZDG in terms of a single Dreibein, that involves an infinite number of derivatives. At the critical points, ZDG can be conjectured to be dual to a logarithmic conformal field theory with zero central charges, characterized by new anomalies whose conjectured values are calculated

  13. Asymptotically AdS spacetimes with a timelike Kasner singularity

    Ren, Jie

    2016-07-01

    Exact solutions to Einstein's equations for holographic models are presented and studied. The IR geometry has a timelike cousin of the Kasner singularity, which is the less generic case of the BKL (Belinski-Khalatnikov-Lifshitz) singularity, and the UV is asymptotically AdS. This solution describes a holographic RG flow between them. The solution's appearance is an interpolation between the planar AdS black hole and the AdS soliton. The causality constraint is always satisfied. The entanglement entropy and Wilson loops are discussed. The boundary condition for the current-current correlation function and the Laplacian in the IR is examined. There is no infalling wave in the IR, but instead, there is a normalizable solution in the IR. In a special case, a hyperscaling-violating geometry is obtained after a dimensional reduction.

  14. Null warped AdS in higher spin gravity

    Breunhoelder, Veronika; Grumiller, Daniel; Prohazka, Stefan

    2015-01-01

    We equip three-dimensional spin-3 gravity in the principal embedding with a new set of boundary conditions that we call "asymptotically null warped AdS". We find a chiral copy of the Polyakov-Bershadsky algebra as asymptotic symmetry algebra, reminiscent of the situation in topologically massive gravity with strict null warped AdS boundary conditions. We prove the invertibility of the map between zuvielbein and metric variables and construct a global gauge transformation to half of AdS spin-3 gravity in the diagonal embedding. This explains why the theory is chiral and why the Polyakov-Bershadsky algebra arises. We then introduce chemical potentials, derive the entropy, free energy, and the holographic response functions, and conclude with a discussion.

  15. Branes in the euclidean AdS3

    In this work we propose an exact microscopic description of maximally symmetric branes in a euclidean AdS3 background. As shown by Bachas and Petropoulos, the most important such branes are localized along a euclidean AdS2 is contained in AdS3. We provide explicit formulas for the coupling of closed strings to such branes (boundary states) and for the spectral density of open strings. The latter is computed in two different ways first in terms of the open string reflection amplitude and then also from the boundary states by world-sheet duality. This gives rise to an important Cardy type consistency check. All the results are compared in detail with the geometrical picture. We also discuss a second class of branes with spherical symmetry and finally comment on some implications for D-branes in a 2D back hole geometry. (author)

  16. New Massive Gravity and AdS4 Counterterms

    We show that the recently proposed Dirac-Born-Infeld extension of new massive gravity emerges naturally as a counterterm in four-dimensional anti-de Sitter space (AdS4). The resulting on-shell Euclidean action is independent of the cutoff at zero temperature. We also find that the same choice of counterterm gives the usual area law for the AdS4 Schwarzschild black hole entropy in a cutoff-independent manner. The parameter values of the resulting counterterm action correspond to a c=0 theory in the context of the duality between AdS3 gravity and two-dimensional conformal field theory. We rewrite this theory in terms of the gauge field that is used to recast 3D gravity as a Chern-Simons theory.

  17. All AdS7 solutions of type II supergravity

    In M-theory, the only AdS7 supersymmetric solutions are AdS7×S4 and its orbifolds. In this paper, we find and classify new supersymmetric solutions of the type AdS7×M3 in type II supergravity. While in IIB none exist, in IIA with Romans mass (which does not lift to M-theory) there are many new ones. We use a pure spinor approach reminiscent of generalized complex geometry. Without the need for any Ansatz, the system determines uniquely the form of the metric and fluxes, up to solving a system of ODEs. Namely, the metric on M3 is that of an S2 fibered over an interval; this is consistent with the Sp(1) R-symmetry of the holographically dual (1,0) theory. By including D8 brane sources, one can numerically obtain regular solutions, where topologically M3≅S3

  18. Entanglement entropy for free scalar fields in AdS

    Sugishita, Sotaro

    2016-01-01

    We compute entanglement entropy for free massive scalar fields in anti-de Sitter (AdS) space. The entangling surface is a minimal surface whose boundary is a sphere at the boundary of AdS. The entropy can be evaluated from the thermal free energy of the fields on a topological black hole by using the replica method. In odd-dimensional AdS, exact expressions of the Renyi entropy S_n are obtained for arbitrary n. We also evaluate 1-loop corrections coming from the scalar fields to holographic entanglement entropy. Applying the results, we compute the leading difference of entanglement entropy between two holographic CFTs related by a renormalization group flow triggered by a double trace deformation. The difference is proportional to the shift of a central charge under the flow.

  19. New massive gravity and AdS(4) counterterms.

    Jatkar, Dileep P; Sinha, Aninda

    2011-04-29

    We show that the recently proposed Dirac-Born-Infeld extension of new massive gravity emerges naturally as a counterterm in four-dimensional anti-de Sitter space (AdS(4)). The resulting on-shell Euclidean action is independent of the cutoff at zero temperature. We also find that the same choice of counterterm gives the usual area law for the AdS(4) Schwarzschild black hole entropy in a cutoff-independent manner. The parameter values of the resulting counterterm action correspond to a c=0 theory in the context of the duality between AdS(3) gravity and two-dimensional conformal field theory. We rewrite this theory in terms of the gauge field that is used to recast 3D gravity as a Chern-Simons theory. PMID:21635026

  20. Towards integrability for AdS3/CFT2

    We review the recent progress towards applying worldsheet integrability techniques to the AdS3/CFT2 correspondence to find its all-loop S matrix and Bethe–Yang equations. We study in full detail the massive sector of AdS3×S3×T4 superstrings supported by pure Ramond–Ramond (RR) fluxes. The extension of this machinery to accommodate massless modes, to the AdS3×S3×S3×S1 pure-RR background and to backgrounds supported by mixed background fluxes is also reviewed. While the results discussed here were found elsewhere, our presentation sometimes deviates from the one found in the original literature in an effort to be pedagogical and self-contained. (topical review)

  1. Transport and logistics as network competencies in a localized industrial cluster

    Hansen, Leif Gjesing

    2004-01-01

    This chapter argues that transport is more than infrastructure and transport capacity for the processes governing industrial organisation.......This chapter argues that transport is more than infrastructure and transport capacity for the processes governing industrial organisation....

  2. Logarithmic conformal field theories and AdS correspondence

    Khorrami, A. M. Ghezelbash. M.; Aghamohammadi, A

    1998-01-01

    We generalize the Maldacena correspondence to the logarithmic conformal field theories. We study the correspondence between field theories in (d+1)-dimensional AdS space and the d-dimensional logarithmic conformal field theories in the boundary of $AdS_{d+1}$. Using this correspondence, we get the n-point functions of the corresponding logarithmic conformal field theory in d-dimensions.

  3. Disruption Management in Passenger Transportation - from Air to Tracks

    Clausen, Jens

    2007-01-01

    world has show a dramatic increase as well. Public transportation by e.g. rail has come into focus, and hence also the service level provided by suppliers ad public transportation. These transportation systems are likewise very vulnerable to disruptions. In the airline industry there is a long tradition...... disrupted operations are becoming available. The use of advanced planning and recovery methods in the railway industry currently gains momentum. The current paper gives a short overview over the methods used for planning and disruption management in the airline industry. The situation regarding railway......Over the last 10 years there has been a tremendous growth in air transportation of passengers. Both airports and airspace are close to saturation with respect to capacity, leading to delays caused by disruptions. At the same time the amount of vehicular trac around and in all larger cities of the...

  4. Capacity Statement for Railways

    Landex, Alex

    2007-01-01

    The subject “Railway capacity” is a combination of the capacity consumption and how the capacity is utilized. The capacity utilization of railways can be divided into 4 core elements: The number of trains; the average speed; the heterogeneity of the operation; and the stability. This article...... describes how the capacity consumption for railways can be worked out and analytical measurements of how the capacity is utilized. Furthermore, the article describes how it is possible to state and visualize railway capacity. Having unused railway capacity is not always equal to be able to operate more...... trains. This is due to network effects in the railway system and due to the fact that more trains results in lower punctuality....

  5. Perturbative entanglement thermodynamics for AdS spacetime: renormalization

    Mishra, Rohit; Singh, Harvendra

    2015-01-01

    We study the effect of charged excitations in the AdS spacetime on the first law of entanglement thermodynamics. It is found that `boosted' AdS black holes give rise to a more general form of first law which includes chemical potential and charge density. To obtain this result we have to resort to a second order perturbative calculation of entanglement entropy for small size subsystems. At first order the form of entanglement law remains unchanged even in the presence of charged excitations. ...

  6. Smoothed Transitions in Higher Spin AdS Gravity

    Banerjee, Shamik; Castro, Alejandra; Hellerman, Simeon; Hijano, Eliot; Lepage-Jutier, Arnaud; Maloney, Alexander; Shenker, Stephen

    2012-01-01

    We consider CFTs conjectured to be dual to higher spin theories of gravity in AdS_3 and AdS_4. Two dimensional CFTs with W_N symmetry are considered in the lambda=0 (k --> infinity) limit, where they are conjectured to be described by continuous orbifolds. The torus partition function is computed, using reasonable assumptions, and equals that of a free field theory. We find no phase transition at temperatures of order one; the usual Hawking-Page phase transition is removed by the highly degen...

  7. Small black holes in global AdS spacetime

    Jokela, Niko; Vuorinen, Aleksi

    2015-01-01

    We study finite temperature correlation functions and quasinormal modes in a strongly coupled conformal field theory holographically dual to a small black hole in global Anti-de Sitter spacetime. Upon variation of the black hole radius, our results smoothly interpolate between known limits corresponding to large black holes and thermal AdS space, implying that a non-Hermitian eigenvalue problem gets continuously transitioned into a Hermitian one. This provides justification for the use of small black holes as regulators in studies of black hole formation in global AdS spacetime.

  8. Phases of Global AdS Black Holes

    Basu, Pallab; Subramanian, P N Bala

    2016-01-01

    We study the phases of gravity coupled to a charged scalar and gauge field in an asymptotically Anti-de Sitter spacetime ($AdS_4$) in the grand canonical ensemble. For the conformally coupled scalar, an intricate phase diagram is charted out between the four relevant solutions: global AdS, boson star, Reissner-Nordstrom black hole and the hairy black hole. The nature of the phase diagram undergoes qualitative changes as the charge of the scalar is changed, which we discuss. We also discuss the new features that arise in the extremal limit.

  9. Phases of global AdS black holes

    Basu, Pallab; Krishnan, Chethan; Subramanian, P. N. Bala

    2016-06-01

    We study the phases of gravity coupled to a charged scalar and gauge field in an asymptotically Anti-de Sitter spacetime ( AdS 4) in the grand canonical ensemble. For the conformally coupled scalar, an intricate phase diagram is charted out between the four relevant solutions: global AdS, boson star, Reissner-Nordstrom black hole and the hairy black hole. The nature of the phase diagram undergoes qualitative changes as the charge of the scalar is changed, which we discuss. We also discuss the new features that arise in the extremal limit.

  10. AdS black holes as reflecting cavities

    We use the identification between null singularities of correlators in the bulk with time singularities in the boundary correlators to study the analytic structure of time-dependent thermal Green functions using the eikonal approximation for classical solutions in the AdS black hole background. We show that the location of singularities in complex time can be understood in terms of null rays bouncing on the boundaries and singularities of the eternal black hole, giving the picture of a 'reflecting cavity'. We can then extract the general analytic expression for the asymptotic values of the frequencies of quasinormal modes in large AdS black holes.

  11. AdS black holes as reflecting cavities

    Amado, Irene

    2008-01-01

    We use the identification between null singularities of correlators in the bulk with time singularities in the boundary correlators to study the analytic structure of time-dependent thermal Green functions using the eikonal approximation for classical solutions in the AdS black hole background. We show that the location of singularities in complex time can be understood in terms of null rays bouncing on the boundaries and singularities of the eternal black hole, giving the picture of a `reflecting cavity'. We can then extract the general analytic expression for the asymptotic values of the frequencies of quasinormal modes in large AdS black holes.

  12. Branes in AdS and pp-wave spacetimes

    Skenderis, K; Skenderis, Kostas; Taylor, Marika

    2002-01-01

    We find half supersymmetric AdS-embeddings in AdS_5 x S^5 corresponding to all quarter BPS orthogonal intersections of D3-branes with Dp-branes. A particular case is the Karch-Randall embedding AdS_4 x S^2. We explicitly prove that these embeddings are supersymmetric by showing that the kappa symmetry projections are compatible with half of the target space Killing spinors and argue that all these cases lead to AdS/dCFT dualities involving a CFT with a defect. We also find an asymptotically AdS_4 x S^2 embedding that corresponds to a holographic RG-flow on the defect. We then consider the pp-wave limit of the supersymmetric AdS-embeddings and show how it leads to half supersymmetric D-brane embeddings in the pp-wave background. We systematically analyze D-brane embeddings in the pp-wave background along with their supersymmetry. We construct all supersymmetric D-branes wrapped along the light-cone using operators in the dual gauge theory: the open string states are constructed using defect fields. We also fin...

  13. Positivity of energy for asymptotically locally AdS spacetimes

    Cheng, M C N; Cheng, Miranda C.N.; Skenderis, Kostas

    2005-01-01

    We derive necessary conditions for the spinorial Witten-Nester energy to be well-defined for asymptotically locally AdS spacetimes. We find that the conformal boundary should admit a spinor satisfying certain differential conditions and in odd dimensions the boundary metric should be conformally Einstein. We show that these conditions are satisfied by asymptotically AdS spacetimes. The gravitational energy (obtained using the holographic stress energy tensor) and the spinorial energy are equal in even dimensions and differ by a bounded quantity related to the conformal anomaly in odd dimensions.

  14. Mixed-symmetry fields in AdS(5), conformal fields, and AdS/CFT

    Metsaev, R R

    2014-01-01

    Mixed-symmetry arbitrary spin massive, massless, and self-dual massive fields in AdS(5) are studied. Light-cone gauge actions for such fields leading to decoupled equations of motion are constructed. Light-cone gauge formulation of mixed-symmetry anomalous conformal currents and shadows in 4d flat space is also developed. AdS/CFT correspondence for normalizable and non-normalizable modes of mixed-symmetry AdS fields and the respective boundary mixed-symmetry anomalous conformal currents and shadows is studied. We demonstrate that the light-cone gauge action for massive mixed-symmetry AdS field evaluated on solution of the Dirichlet problem amounts to the light-cone gauge 2-point vertex of mixed-symmetry anomalous shadow. Also we show that UV divergence of the action for mixed-symmetry massive AdS field with some particular value of mass parameter evaluated on the Dirichlet problem amounts to the action of long mixed-symmetry conformal field, while UV divergence of the action for mixed-symmetry massless AdS fi...

  15. AdS (instability: Lessons from the scalar field

    Pallab Basu

    2015-06-01

    Full Text Available We argued in arXiv:1408.0624 that the quartic scalar field in AdS has features that could be instructive for answering the gravitational stability question of AdS. Indeed, the conserved charges identified there have recently been observed in the full gravity theory as well. In this paper, we continue our investigation of the scalar field in AdS and provide evidence that in the Two-Time Formalism (TTF, even for initial conditions that are far from quasi-periodicity, the energy in the higher modes at late times is exponentially suppressed in the mode number. Based on this and some related observations, we argue that there is no thermalization in the scalar TTF model within time-scales that go as ∼1/ϵ2, where ϵ measures the initial amplitude (with only low-lying modes excited. It is tempting to speculate that the result holds also for AdS collapse.

  16. Penrose inequality for asymptotically AdS spaces

    Itkin, Igor [Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel); Oz, Yaron, E-mail: yaronoz@post.tau.ac.il [Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel)

    2012-02-28

    In general relativity, the Penrose inequality relates the mass and the entropy associated with a gravitational background. If the inequality is violated by an initial Cauchy data, it suggests a creation of a naked singularity, thus providing means to consider the cosmic censorship hypothesis. We propose a general form of Penrose inequality for asymptotically locally AdS spaces.

  17. BRST Quantization of String Theory in AdS(3)

    Pakman, A

    2003-01-01

    We study the BRST quantization of bosonic and NSR strings propagating in AdS(3) x N backgrounds. The no-ghost theorem is proved using the Frenkel-Garland-Zuckerman method. Regular and spectrally-flowed representations of affine SL(2,R) appear on an equal footing. Possible generalizations to related curved backgrounds are discussed.

  18. Internet Advertising. Google AdWords versus Facebook Ads

    Paul PAŞCU

    2014-05-01

    Full Text Available This article describes how to use the applications for Internet advertising, Google AdWords and Facebook Ads. Our attempt is to present the advantages and disadvantages of each of them, the costs and benefits, a useful aspect for companies that plan to start advertising campaigns on the Internet.

  19. Entanglement temperature and perturbed AdS3 geometry

    Levine, G. C.; Caravan, B.

    2016-06-01

    Generalizing the first law of thermodynamics, the increase in entropy density δ S (x ) of a conformal field theory (CFT) is proportional to the increase in energy density, δ E (x ) , of a subsystem divided by a spatially dependent entanglement temperature, TE(x ) , a fixed parameter determined by the geometry of the subsystem, crossing over to thermodynamic temperature at high temperatures. In this paper we derive a generalization of the thermodynamic Clausius relation, showing that deformations of the CFT by marginal operators are associated with spatial temperature variations, δ TE(x ) , and spatial energy correlations play the role of specific heat. Using AdS/CFT duality we develop a relationship between a perturbation in the local entanglement temperature of the CFT and the perturbation of the bulk AdS metric. In two dimensions, we demonstrate a method through which direct diagonalizations of the boundary quantum theory may be used to construct geometric perturbations of AdS3 .

  20. AdS5 backgrounds with 24 supersymmetries

    Beck, S.; Gutowski, J.; Papadopoulos, G.

    2016-06-01

    We prove a non-existence theorem for smooth AdS 5 solutions with connected, compact without boundary internal space that preserve strictly 24 supersymmetries. In particular, we show that D = 11 supergravity does not admit such solutions, and that all such solutions of IIB supergravity are locally isometric to the AdS 5 × S 5 maximally supersymmetric background. Furthermore, we prove that (massive) IIA supergravity also does not admit such solutions, provided that the homogeneity conjecture for massive IIA supergravity is valid. In the context of AdS/CFT these results imply that if gravitational duals for strictly mathcal{N}=3 superconformal theories in 4-dimensions exist, they are either singular or their internal spaces are not compact.

  1. AdS5 Backgrounds with 24 Supersymmetries

    Beck, S W; Papadopoulos, G

    2016-01-01

    We prove a non-existence theorem for smooth AdS5 solutions with connected, compact without boundary internal space that preserve strictly 24 supersymmetries. In particular, we show that D=11 supergravity does not admit such solutions, and that all such solutions of IIB supergravity are locally isometric to the AdS_5 * S^5 maximally supersymmetric background. Furthermore, we prove that (massive) IIA supergravity also does not admit such solutions, provided that the homogeneity conjecture for massive IIA supergravity is valid. In the context of AdS/CFT these results imply that if strictly N=3 superconformal theories in 4-dimensions exist, their gravitational dual backgrounds are either singular or their internal spaces are not compact.

  2. Monitoring Infrastructure Capacity

    David Levinson

    2000-01-01

    This paper examines the issues around monitoring of the capacity of public sector infrastructure to absorb land development.This paper first introduces Montgomery County¹s growth management system. It then offers two theories to justify monitoring infrastructure utilization for the purposes of establishing development capacity. The first, drawn from ecology is based on the notion of environmental carrying capacity. The second, from economics, employs the notion of externalities. However, neit...

  3. Evaluation of railway capacity

    Landex, Alex; Kaas, Anders H.; Schittenhelm, Bernd;

    2006-01-01

    This paper describes the relatively new UIC 406 method for calculating capacity consumption on railway lines. The UIC 406 method is an easy and effective way of calculating the capacity consumption, but it is possible to expound the UIC 406 method in different ways which can lead to different...... of a railway network. Some of the aspects which have to be paid attention to making annual capacity statements are presented too....

  4. Nuclear Capacity Auctions

    Fridolfsson, Sven-Olof; Tangerås, Thomas

    2011-01-01

    We propose nuclear capacity auctions as a means to improve the incentives for investing in nuclear power. A properly designed auction would (i) allocate the license to the most efficient bidder; (ii) sell the license if and only if new nuclear power was socially optimal. In particular, capacity auctions open the market for large-scale entry by outside firms. Requiring licensees to sell a share of capacity as virtual power plant contracts increases auction efficiency by softening incumbent pro...

  5. Economic performance of irrigation capacity development to adapt to climate in the American Southwest

    Ward, Frank A.; Crawford, Terry L.

    2016-09-01

    Growing demands for food security to feed increasing populations worldwide have intensified the search for improved performance of irrigation, the world's largest water user. These challenges are raised in the face of climate variability and from growing environmental demands. Adaptation measures in irrigated agriculture include fallowing land, shifting cropping patterns, increased groundwater pumping, reservoir storage capacity expansion, and increased production of risk-averse crops. Water users in the Gila Basin headwaters of the U.S. Lower Colorado Basin have faced a long history of high water supply fluctuations producing low-valued defensive cropping patterns. To date, little research grade analysis has investigated economically viable measures for irrigation development to adjust to variable climate. This gap has made it hard to inform water resource policy decisions on workable measures to adapt to climate in the world's dry rural areas. This paper's contribution is to illustrate, formulate, develop, and apply a new methodology to examine the economic performance from irrigation capacity improvements in the Gila Basin of the American Southwest. An integrated empirical optimization model using mathematical programming is developed to forecast cropping patterns and farm income under two scenarios (1) status quo without added storage capacity and (2) with added storage capacity in which existing barriers to development of higher valued crops are dissolved. We find that storage capacity development can lead to a higher valued portfolio of irrigation production systems as well as more sustained and higher valued farm livelihoods. Results show that compared to scenario (1), scenario (2) increases regional farm income by 30%, in which some sub regions secure income gains exceeding 900% compared to base levels. Additional storage is most economically productive when institutional and technical constraints facing irrigated agriculture are dissolved. Along with

  6. The French capacity mechanism

    The French capacity mechanism has been design to ensure security of supply in the context of the energy transition. This energy transition challenges the electricity market design with several features: peak load growth, the development of renewables, demand response,... To ensure security of supply in this context, a capacity mechanism is being implemented in France. It is a market wide capacity obligation on electricity suppliers, based on market principles. Suppliers are responsible for forecasting their obligation, which corresponds to their contribution to winter peak load, and must procure enough capacity certificates to meet their obligations. Capacity certificates are granted to capacities through a certification process, which assesses their contribution to security of supply on the basis of availability commitments. This certification process is technology neutral and performance based, associated with controls and penalties in case of non compliance. Demand Side is fully integrated in the market, either through the reduction of suppliers' capacity obligation or direct participation after certification. In addition to the expected benefits in terms of security of supply, the French capacity market will foster the development of demand response. The participation of foreign capacities will require adaptations which are scheduled in a road-map, and could pave the way for further European integration of energy policies. (authors)

  7. The coming capacity shortfall: the constraints on OPEC's investment in spare capacity expansion

    The principal oil producing countries have recognized that they have insufficient production capacity to support strong, future demand growth. Since 1990 they have announced ambitious production capacity expansion programmes. The total of these announced programmes will exceed $170 billion by the end of 1995, not including the huge capital needs of the former USSR. These programmes will run into difficulties that will result in much less capacity being added than is now targeted. The problems will vary according to the different character of capacity expansion that each country faces. Each programme will have different costs and different technological challenges. In addition, each of the principal producing states confronts different degrees of financial, policy and structural as well as technological constraints on their efforts to expand capacity. It therefore appears that the announced expansion plans will fall short of targets. This will increase the pressure on oil price as demand grows through the mid-1990s. (author)

  8. Robust message routing for mobile (wireless) ad hoc networks.

    Goldsby, Michael E.; Johnson, Michael M.; Kilman, Dominique Marie (Sandia National Laboratories, Albuquerque, NM); Bierbaum, Neal Robert; Chen, Helen Y.; Ammerlahn, Heidi R.; Tsang, Rose P.; Nicol, David M. (University of Illinois, Urbana, IL)

    2004-01-01

    This report describes the results of research targeting improvements in the robustness of message transport in wireless ad hoc networks. The first section of the report provides an analysis of throughput and latency in the wireless medium access control (MAC) layer and relates the analysis to the commonly used 802.11 protocol. The second section describes enhancements made to several existing models of wireless MAC and ad hoc routing protocols; the models were used in support of the work described in the following section. The third section of the report presents a lightweight transport layer protocol that is superior to TCP for use in wireless networks. In addition, it introduces techniques that improve the performance of any ad hoc source routing protocol. The fourth section presents a novel, highly scalable ad hoc routing protocol that is based on geographic principles but requires no localization hardware.

  9. A simple dynamic energy capacity model

    I develop a simple dynamic model showing how total energy capacity is allocated to two different uses and how these uses and their corresponding energy flows are related and behave through time. The control variable of the model determines the allocation. All the variables of the model are in terms of a composite energy equivalent measured in BTU's. A key focus is on the shadow price of energy capacity and its behavior through time. Another key focus is on the behavior of the control variable that determines the allocation of overall energy capacity. The matching or linking of the model's variables to real world U.S. energy data is undertaken. In spite of some limitations of the data, the model and its behavior fit the data fairly well. Some energy policy implications are discussed. - Highlights: ► The model shows how energy capacity is allocated to current output production versus added energy capacity production. ► Two variables in the allocation are the shadow price of capacity and the control variable that determines the allocation. ► The model was linked to U.S. historical energy data and fit the data quite well. ► In particular, the policy control variable was cyclical and consistent with the model. ► Policy implications relevant to the allocation of energy capacity are discussed briefly.

  10. The PredictAD project

    Antila, Kari; Lötjönen, Jyrki; Thurfjell, Lennart;

    2013-01-01

    objective of the PredictAD project was to find and integrate efficient biomarkers from heterogeneous patient data to make early diagnosis and to monitor the progress of AD in a more efficient, reliable and objective manner. The project focused on discovering biomarkers from biomolecular data...