ON THE CAPACITY REGION OF WIRELESS AD HOC RELAY NETWORKS
Institute of Scientific and Technical Information of China (English)
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.
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 ...
Capacity of Wireless Ad Hoc Networks with Opportunistic Collaborative Communications
Directory of Open Access Journals (Sweden)
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.
Capacity of Wireless Ad Hoc Networks with Opportunistic Collaborative Communications
Directory of Open Access Journals (Sweden)
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.
Sediment transport capacity of hyperconcentrated flow
Institute of Scientific and Technical Information of China (English)
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.
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
An Effective Capacity Estimation Scheme in IEEE802.11-based Ad Hoc Networks
Directory of Open Access Journals (Sweden)
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.
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...
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...
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.
High capacity carrier ethernet transport networks
DEFF Research Database (Denmark)
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...
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.
Development of high capacity transportable storage cask
International Nuclear Information System (INIS)
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)
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
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.
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 ...
Determinants of Capacity Utilization in Road Freight Transportation
DEFF Research Database (Denmark)
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...
Capacity Utilisation of Vehicles for Road Freight Transport
DEFF Research Database (Denmark)
Kveiborg, Ole; Abate, Megersa Abera
Purpose This chapter discusses a central aspect of freight transport – capacity 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...
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.
Effects of exercise training on coronary transport capacity
International Nuclear Information System (INIS)
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)
Energy Technology Data Exchange (ETDEWEB)
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.
DEFF Research Database (Denmark)
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...
International Nuclear Information System (INIS)
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
DEFF Research Database (Denmark)
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...
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...
International Nuclear Information System (INIS)
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
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
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...
Institute of Scientific and Technical Information of China (English)
无
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.
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
Opportunistic Hybrid Transport Protocol (OHTP for Cognitive Radio Ad Hoc Sensor Networks
Directory of Open Access Journals (Sweden)
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.
International Nuclear Information System (INIS)
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
Measuring the pollutant transport capacity of dissolved organic matter in complex matrixes
DEFF Research Database (Denmark)
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....
Optimum Repartition of Transport Capacities in the Logistic System using Dynamic Programming
Directory of Open Access Journals (Sweden)
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.
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.
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...
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...
The meaning of different limiters relations for definig public transport routes capacity
Directory of Open Access Journals (Sweden)
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.
Optimal spatial transportation networks where link costs are sublinear in link capacity
International Nuclear Information System (INIS)
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
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
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
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...
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...
Auction design for gas pipeline transportation capacity-The case of Nabucco and its open season
International Nuclear Information System (INIS)
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.
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
Competence and Capacity-Building Requirements in Transport and Logistics Market
Directory of Open Access Journals (Sweden)
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.
Directory of Open Access Journals (Sweden)
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
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
The Use of Artificial Neural Networks to Assess the Capacity of Transport Measures
Directory of Open Access Journals (Sweden)
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
SLC2A9 is a high-capacity urate transporter in humans.
Directory of Open Access Journals (Sweden)
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.
Peritoneal transport in CAPD patients with permanent loss of ultrafiltration capacity
International Nuclear Information System (INIS)
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
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).
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
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...
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
International Nuclear Information System (INIS)
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
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.
International Nuclear Information System (INIS)
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
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
DEFF Research Database (Denmark)
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...
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.
MX8: the next generation high capacity system for land transport of Mox fuel
International Nuclear Information System (INIS)
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.)
Determination of serum iron and of the transport capacity of iron by transferrin
International Nuclear Information System (INIS)
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)
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
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
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.
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
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…
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
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...
DEFF Research Database (Denmark)
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...
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...
International Nuclear Information System (INIS)
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
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
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...
International Nuclear Information System (INIS)
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
Energy Technology Data Exchange (ETDEWEB)
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.
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
International Nuclear Information System (INIS)
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
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.
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.
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...
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.
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.
Directory of Open Access Journals (Sweden)
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.
International Nuclear Information System (INIS)
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
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
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.
Directory of Open Access Journals (Sweden)
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.
... 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, ...
International Nuclear Information System (INIS)
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
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.
Directory of Open Access Journals (Sweden)
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.
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
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
Energy Technology Data Exchange (ETDEWEB)
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.
International Nuclear Information System (INIS)
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
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...
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
Directory of Open Access Journals (Sweden)
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.
International Nuclear Information System (INIS)
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)
Energy Technology Data Exchange (ETDEWEB)
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.
International Nuclear Information System (INIS)
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.
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
International Nuclear Information System (INIS)
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
DEFF Research Database (Denmark)
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...
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...
Institute of Scientific and Technical Information of China (English)
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.
Directory of Open Access Journals (Sweden)
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.
Two AdS2 branes in the euclidean AdS3
International Nuclear Information System (INIS)
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)
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.
International Nuclear Information System (INIS)
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
AdS solutions through transgression
International Nuclear Information System (INIS)
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.)
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...
Enhanced Wireless Network Ad Hoc Pattern
Directory of Open Access Journals (Sweden)
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.
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...
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].
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.
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.
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.
ADS National Programmes: Germany
International Nuclear Information System (INIS)
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
ADS National Programmes: Netherlands
International Nuclear Information System (INIS)
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
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.
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…
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.
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.
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 ...
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.
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
Institute of Scientific and Technical Information of China (English)
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。
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...
Refined holographic entanglement entropy for the AdS solitons and AdS black holes
International Nuclear Information System (INIS)
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
DEFF Research Database (Denmark)
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...
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...
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.
International Nuclear Information System (INIS)
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
Institute of Scientific and Technical Information of China (English)
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.
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.
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...
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
Holography of AdS vacuum bubbles
International Nuclear Information System (INIS)
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.
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.
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...
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.
Energy Technology Data Exchange (ETDEWEB)
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)
ADS National Programmes: India
International Nuclear Information System (INIS)
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
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...
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…
International Nuclear Information System (INIS)
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)
International Nuclear Information System (INIS)
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)
Capacity Value of Concentrating Solar Power Plants
Energy Technology Data Exchange (ETDEWEB)
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%.
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.
DEFF Research Database (Denmark)
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...
Directory of Open Access Journals (Sweden)
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.
Vertical barriers with increased sorption capacities
Energy Technology Data Exchange (ETDEWEB)
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.
Vertical barriers with increased sorption capacities
International Nuclear Information System (INIS)
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
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...
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.
International Nuclear Information System (INIS)
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.
AdS backgrounds from black hole horizons
International Nuclear Information System (INIS)
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)
ADS National Programmes: Italy
International Nuclear Information System (INIS)
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
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...
DEFF Research Database (Denmark)
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...
ADS National Programmes: China
International Nuclear Information System (INIS)
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
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
ADS National Programmes: Belgium
International Nuclear Information System (INIS)
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
Directory of Open Access Journals (Sweden)
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.
ADS specific accelerator developments: Status in Japan
International Nuclear Information System (INIS)
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
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...
ADS National Programmes: Japan
International Nuclear Information System (INIS)
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
Nuclear transport - The regulatory dimension
International Nuclear Information System (INIS)
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
High capacity carrier ethernet transport networks
DEFF Research Database (Denmark)
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...
DEFF Research Database (Denmark)
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...
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.
ADS National Programmes: France
International Nuclear Information System (INIS)
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
AdS 3-manifolds and Higgs bundles
DEFF Research Database (Denmark)
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...
Directory of Open Access Journals (Sweden)
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
Evaporation of large black holes in AdS
International Nuclear Information System (INIS)
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.
Institute of Scientific and Technical Information of China (English)
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.
DEFF Research Database (Denmark)
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....
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
Directory of Open Access Journals (Sweden)
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].
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...
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.
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.
International Nuclear Information System (INIS)
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)
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.
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.
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.
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...
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...
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.
Killing spinors and supersymmetry on AdS
International Nuclear Information System (INIS)
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
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.
Conical singularities in AdS space time
International Nuclear Information System (INIS)
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)
Institute of Scientific and Technical Information of China (English)
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。
Managing the market risk in pipeline capacity positions
International Nuclear Information System (INIS)
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
Thermodynamics of large AdS black holes
International Nuclear Information System (INIS)
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
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.
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.
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.
ADS National Programmes: Belarus
International Nuclear Information System (INIS)
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
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...
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...
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.
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...
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.
... 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 ...
PAYMENT CAPACITY SENSITIVITY FACTORS
Directory of Open Access Journals (Sweden)
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.
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.
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.
Logarithmic AdS waves and Zwei-Dreibein gravity
International Nuclear Information System (INIS)
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
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.
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.
International Nuclear Information System (INIS)
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)
New Massive Gravity and AdS4 Counterterms
International Nuclear Information System (INIS)
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.
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.
All AdS7 solutions of type II supergravity
International Nuclear Information System (INIS)
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
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.
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
Towards integrability for AdS3/CFT2
International Nuclear Information System (INIS)
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)
Capacity Statement for Railways
DEFF Research Database (Denmark)
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....
Transport and logistics as network competencies in a localized industrial cluster
DEFF Research Database (Denmark)
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....
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.
Disruption Management in Passenger Transportation - from Air to Tracks
DEFF Research Database (Denmark)
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...
AdS black holes as reflecting cavities
International Nuclear Information System (INIS)
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.
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.
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...
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.
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.
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.
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...
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.
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. ...
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...
AdS (instability: Lessons from the scalar field
Directory of Open Access Journals (Sweden)
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.
Penrose inequality for asymptotically AdS spaces
Energy Technology Data Exchange (ETDEWEB)
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.
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.
Internet Advertising. Google AdWords versus Facebook Ads
Directory of Open Access Journals (Sweden)
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.
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 .
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.
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.
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...
Evaluation of railway capacity
DEFF Research Database (Denmark)
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....
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...
International Nuclear Information System (INIS)
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)
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
The coming capacity shortfall: the constraints on OPEC's investment in spare capacity expansion
International Nuclear Information System (INIS)
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)
A simple dynamic energy capacity model
International Nuclear Information System (INIS)
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.
Robust message routing for mobile (wireless) ad hoc networks.
Energy Technology Data Exchange (ETDEWEB)
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.
DEFF Research Database (Denmark)
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...
Designing added functions in engineered cementitious composites
Yang, En-Hua
In this dissertation, a new and systematic material design approach is developed for ECC with added functions through material microstructures linkage to composite macroscopic behavior. The thesis research embodies theoretical development by building on previous ECC micromechanical models, and experimental investigations into three specific new versions of ECC with added functions aimed at addressing societal demands of our built infrastructure. Specifically, the theoretical study includes three important ECC modeling elements: Steady-state crack propagation analyses and simulation, predictive accuracy of the fiber bridging constitutive model, and development of the rate-dependent strain-hardening criteria. The first element establishes the steady-state cracking criterion as a fundamental requirement for multiple cracking behavior in brittle matrix composites. The second element improves the accuracy of crack-width prediction in ECC. The third element establishes the micromechanics basis for impact-resistant ECC design. Three new ECCs with added functions were developed and experimentally verified in this thesis research through the enhanced theoretical framework. A green ECC incorporating a large volume of industrial waste was demonstrated to possess reduced crack width and drying shrinkage. The self-healing ECC designed with tight crack width was demonstrated to recover transport and mechanical properties after microcrack damage when exposed to wet and dry cycles. The impact-resistant ECC was demonstrated to retain tensile ductility with increased strength under moderately high strain-rate loading. These new versions of ECC with added functions are expected to contribute greatly to enhancing the sustainability, durability, and safety of civil infrastructure built with ECC. This research establishes the effectiveness of micromechanics-based design and material ingredient tailoring for ECC with added new attributes but without losing its basic tensile ductile
Self-dual warped AdS3 black holes
Chen, Bin; Ning, Bo
2010-12-01
We study a new class of solutions of three-dimensional topological massive gravity. These solutions can be taken as nonextremal black holes, with their extremal counterparts being discrete quotients of spacelike warped AdS3 along the U(1)L isometry. We study the thermodynamics of these black holes and show that the first law is satisfied. We also show that for consistent boundary conditions, the asymptotic symmetry generators form only one copy of the Virasoro algebra with central charge cL=(4νℓ)/(G(ν2+3)), with which the Cardy formula reproduces the black hole entropy. We compute the real-time correlators of scalar perturbations and find a perfect match with the dual conformal field theory (CFT) predictions. Our study provides a novel example of warped AdS/CFT correspondence: the self-dual warped AdS3 black hole is dual to a CFT with nonvanishing left central charge. Moreover, our investigation suggests that the quantum topological massive gravity asymptotic to the same spacelike warped AdS3 in different consistent ways may be dual to different two-dimensional CFTs.
Accelerator development in India for ADS programme
Indian Academy of Sciences (India)
P Singh; S V L S Rao; Rajni Pande; T Basak; Shwetha Roy; M Aslam; P Jain; S C L Srivastava; Rajesh Kumar; P K Nema; S Kailas; V C Sahni
2007-02-01
At BARC, development of a Low Energy High Intensity Proton Accelerator (LEHIPA), as front-end injector of the 1 GeV accelerator for the ADS programme, has been initiated. The major components of LEHIPA (20 MeV, 30 mA) are a 50 keV ECR ion source, a 3 MeV Radio Frequency Quadrupole (RFQ) and a 20 MeV drift tube linac (DTL). The Low Energy Beam Transport (LEBT) and Medium Energy Beam Transport (MEBT) lines match the beam from the ion source to RFQ and from RFQ to DTL respectively. Design of these systems has been completed and fabrication of their prototypes has started. Physics studies of the 20{1000 MeV part of the Linac are also in progress. In this paper, the present status of this project is presented.
String theory in AdS3 background
International Nuclear Information System (INIS)
In this thesis we study string theory in AdS3 background in the context of AdS/CFT correspondence. We discuss unitarity, modular invariance and closure of operator product expansion (OPE) in the theory. A construction of spacetime conformal field theory from worldsheet affine symmetry due to Giveon, Kutasov and Seiberg is presented. The spacetime CFT has the meaning boundary CFT in AdS/CFT correspondence. The knowledge of two dimensional N extended superconformal algebras is used to construct superstrings on AdS3 x N with extended spacetime supersymmetry. A classification of vacua of superstrings on AdS3 is proposed from the knowledge of superconformal algebras in two dimensions. We present some exact solutions of Kniznik-Zamolodochikov (KZ) equation for SL(2, R) WZNW model for four point functions, which have logarithmic singularities of conformally invariant cross ratios, from a simple ansatz. Some asymptotic solutions with logarithmic behaviour are also presented. We analyze the logarithmic solutions and show that they can give rise to logarithmic operators in the theory. It has been shown by OPE analysis and otherwise that representation with SL(2, R) quantum number j = -1/2 play a very special role. The possibility of contribution oj logarithmic operators to the OPE is discussed. We find that OPE can not close or unitary representations if we include the logarithmic operators in the theory. We discuss the implications of logarithmic operators about the unitarity of the theory. The role of singleton representation is clarified in the context of logarithmic operators in AdS/CFT correspondence. (author)
Routing in Terrestrial Free Space Optical Ad-Hoc Networks
Dong, Yao; Sadegh Aminian, Mohammad
2014-01-01
Terrestrial free-space optical (FSO) communication uses visible or infrared wavelengths to broadcast high speed data wirelessly through the atmospheric channel. The performance of terrestrial FSO channel mainly depends on the local atmospheric conditions. Ad hoc networks offer cost-effective solutions for communications in areas where infrastructure is unavailable, e.g., intelligent transport system, disaster recovery and battlefield scenarios. Traditional ad hoc networks operate in the radio...
Comaskey, Brian J.; Scheibner, Karl F.; Ault, Earl R.
2007-05-01
The heat capacity laser concept is extended to systems in which the heat capacity lasing media is a liquid. The laser active liquid is circulated from a reservoir (where the bulk of the media and hence waste heat resides) through a channel so configured for both optical pumping of the media for gain and for light amplification from the resulting gain.
DEFF Research Database (Denmark)
Sameni, Melody Khadem; Preston, John M.
2012-01-01
Growth in rail traffic has not been matched by increases in railway infrastructure. Given this capacity challenge and the current restrictions on public spending, the allocation and the utilization of existing railway capacity are more important than ever. Great Britain has had the greatest growt...
Uncertainty in adaptive capacity
International Nuclear Information System (INIS)
The capacity to adapt is a critical element of the process of adaptation: it is the vector of resources that represent the asset base from which adaptation actions can be made. Adaptive capacity can in theory be identified and measured at various scales, from the individual to the nation. The assessment of uncertainty within such measures comes from the contested knowledge domain and theories surrounding the nature of the determinants of adaptive capacity and the human action of adaptation. While generic adaptive capacity at the national level, for example, is often postulated as being dependent on health, governance and political rights, and literacy, and economic well-being, the determinants of these variables at national levels are not widely understood. We outline the nature of this uncertainty for the major elements of adaptive capacity and illustrate these issues with the example of a social vulnerability index for countries in Africa. (authors)
CAPACITY OF ROTARY LOADING MACHINE ON COAL STOCK FACILITY
Directory of Open Access Journals (Sweden)
Stanislav Živković
2002-12-01
Full Text Available In order to reduce the cost of the stock facility, which might contain large coal masses (usually several hundreds of thousands of tons it is important to have the loading capacity adjusted to the transport and boiler capacity. In the case of either too small or too large capacity of loading machinery a technical incompatibility of the loading and transport system can occur, together with some unecessary investments in too large loading machines. This is why it is necessary to have an accurate determination of working conditions, specific for each stocking capacity (the paper is published in Croatian.
Observing quantum gravity in asymptotically AdS space
Emelyanov, Slava
2015-12-01
The question is studied of whether an observer can discover quantum gravity in the semiclassical regime. It is shown that it is indeed possible to probe a certain quantum gravity effect by employing an appropriately designed detector. The effect is related to the possibility of having topologically inequivalent geometries in the path-integral approach at the same time. A conformal field theory (CFT) state which is expected to describe the eternal anti-de Sitter (AdS) black hole in the large-N limit is discussed. It is argued under certain assumptions that the black hole boundary should be merely a patch of the entire AdS boundary. This leads then to a conclusion that that CFT state is the ordinary CFT vacuum restricted to that patch. If existent, the bulk CFT operators can behave as the ordinary semiclassical quantum field theory in the large-N limit in the weak sense.
Smoothed transitions in higher spin AdS gravity
International Nuclear Information System (INIS)
We consider CFTs conjectured to be dual to higher spin theories of gravity in AdS3 and AdS4. Two-dimensional CFTs with WN symmetry are considered in the λ = 0 (k → ∞) 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 1; the usual Hawking–Page phase transition is removed by the highly degenerate light states associated with conical defect states in the bulk. Three-dimensional Chern–Simons matter CFTs with vector-like matter are considered on T3, where the dynamics is described by an effective theory for the eigenvalues of the holonomies. Likewise, we find no evidence for a Hawking–Page phase transition at a large level k. (paper)
AdS nonlinear instability: moving beyond spherical symmetry
Dias, Oscar J C
2016-01-01
Anti-de Sitter (AdS) is conjectured to be nonlinear unstable to a weakly turbulent mechanism that develops a cascade towards high frequencies, leading to black hole formation [1,2]. We give evidence that the gravitational sector of perturbations behaves differently from the scalar one studied in [2]. In contrast with [2], we find that not all gravitational normal modes of AdS can be nonlinearly extended into periodic horizonless smooth solutions of the Einstein equation. In particular, we show that even seeds with a single normal mode can develop secular resonances, unlike the spherically symmetric scalar field collapse studied in [2]. Moreover, if the seed has two normal modes, more than one resonance can be generated at third order, unlike the spherical collapse of [2]. We also show that weak turbulent perturbative theory predicts the existence of direct and inverse cascades, with the former dominating the latter for equal energy two-mode seeds.
Ambitwistors, oscillators and massless fields on $AdS_5$
Uvarov, D V
2016-01-01
Positive energy unitary irreducible representations of $SU(2,2)$ can be constructed with the aid of bosonic oscillators in (anti)fundamental representation of $SU(2)_L\\times SU(2)_R$ that are closely related to Penrose twistors. Starting with the correspondence between the doubleton representations, homogeneous functions on projective twistor space and on-shell $SL(2,\\mathbb C)$ generalized Weyl curvature spinors and their low-spin counterparts, we study in the similar way the correspondence between the massless representations, homogeneous functions on ambitwistor space and, via the Penrose transform, with the gauge fields on Minkowski boundary of $AdS_5$. The possibilities of reconstructing massless fields on $AdS_5$ and some applications are also discussed.
The Mixed Phase of Charged AdS Black Holes
Directory of Open Access Journals (Sweden)
Piyabut Burikham
2016-01-01
Full Text Available We study the mixed phase of charged AdS black hole and radiation when the total energy is fixed below the threshold to produce a stable charged black hole branch. The coexistence conditions for the charged AdS black hole and radiation are derived for the generic case when radiation particles carry charge. The phase diagram of the mixed phase is demonstrated for both fixed potential and charge ensemble. In the dual gauge picture, they correspond to the mixed phase of quark-gluon plasma (QGP and hadron gas in the fixed chemical potential and density ensemble, respectively. In the nuclei and heavy-ion collisions at intermediate energies, the mixed phase of exotic QGP and hadron gas could be produced. The mixed phase will condense and evaporate into the hadron gas as the fireball expands.
Semiclassical Virasoro Blocks from AdS$_3$ Gravity
Hijano, Eliot; Perlmutter, Eric; Snively, River
2015-01-01
We present a unified framework for the holographic computation of Virasoro conformal blocks at large central charge. In particular, we provide bulk constructions that correctly reproduce all semiclassical Virasoro blocks that are known explicitly from conformal field theory computations. The results revolve around the use of geodesic Witten diagrams, recently introduced in arXiv:1508.00501, evaluated in locally AdS$_3$ geometries generated by backreaction of heavy operators. We also provide an alternative computation of the heavy-light semiclassical block -- in which two external operators become parametrically heavy -- as a certain scattering process involving higher spin gauge fields in AdS$_3$; this approach highlights the chiral nature of Virasoro blocks. These techniques may be systematically extended to compute corrections to these blocks and to interpolate amongst the different semiclassical regimes.
Semiclassical Virasoro blocks from AdS3 gravity
Hijano, Eliot; Kraus, Per; Perlmutter, Eric; Snively, River
2015-12-01
We present a unified framework for the holographic computation of Virasoro conformal blocks at large central charge. In particular, we provide bulk constructions that correctly reproduce all semiclassical Virasoro blocks that are known explicitly from conformal field theory computations. The results revolve around the use of geodesic Witten diagrams, recently introduced in [1], evaluated in locally AdS3 geometries generated by backreaction of heavy operators. We also provide an alternative computation of the heavy-light semiclassical block — in which two external operators become parametrically heavy — as a certain scattering process involving higher spin gauge fields in AdS3; this approach highlights the chiral nature of Virasoro blocks. These techniques may be systematically extended to compute corrections to these blocks and to interpolate amongst the different semiclassical regimes.
Perturbative entanglement thermodynamics for AdS spacetime: Renormalization
Mishra, Rohit
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. But the thermodynamic quantities have to be appropriately `renormalized' at the second order due to the corrections. We work in the perturbative regime where $T_{thermal}\\ll T_E$.
Universal isolation in the AdS landscape
Danielsson, U H; Vargas, S C
2016-01-01
We study the universal conditions for quantum non-perturbative stability against bubble nucleation for pertubatively stable AdS vacua based on positive energy theorems. We also compare our analysis with the pre-existing ones in the literature carried out within the thin-wall approximation. The aforementioned criterion is then tested in two explicit examples describing massive type IIA string theory compactified on $S^3$ and $S^3\\,\\times\\,S^3$, respectively. The AdS landscape of both classes of compactifications is known to consist of a set of isolated points. The main result is that all critical points respecting the Breitenlohner-Freedaman (BF) bound also turn out be stable at a non-perturbative level. Finally, we speculate on the possible universal features that may be extracted from the above specific examples.
Supersymmetric AdS6 solutions of type IIB supergravity
International Nuclear Information System (INIS)
We study the general requirement for supersymmetric AdS6 solutions in type IIB supergravity. We employ the Killing spinor technique and study the differential and algebraic relations among various Killing spinor bilinears to find the canonical form of the solutions. Our result agrees precisely with the work of Apruzzi et al. (JHEP 1411:099, 2014), which used the pure spinor technique. Hoping to identify the geometry of the problem, we also computed four-dimensional theory through the dimensional reduction of type IIB supergravity on AdS6. This effective action is essentially a non-linear sigma model with five scalar fields parametrizing SL(3,ℝ)/SO(2,1), modified by a scalar potential and coupled to Einstein gravity in Euclidean signature. We argue that the scalar potential can be explained by a subgroup CSO(1,1,1) ⊂SL(3,ℝ) in a way analogous to gauged supergravity
Supersymmetric AdS6 solutions of type IIB supergravity
International Nuclear Information System (INIS)
We study the general requirement for supersymmetric AdS6 solutions in type IIB supergravity. We employ the Killing spinor technique and study the differential and algebraic relations among various Killing spinor bilinears to find the canonical form of the solutions. Our result agrees precisely with the work of Apruzzi et al. (JHEP 1411:099, 2014), which used the pure spinor technique. Hoping to identify the geometry of the problem, we also computed four-dimensional theory through the dimensional reduction of type IIB supergravity on AdS6. This effective action is essentially a non-linear sigma model with five scalar fields parametrizing SL(3,R)/ SO(2,1), modified by a scalar potential and coupled to Einstein gravity in Euclidean signature. We argue that the scalar potential can be explained by a subgroup CSO(1,1,1) is contained in SL(3,R) in a way analogous to gauged supergravity. (orig.)
One loop gauge couplings in AdS5
Choi, Kiwoon; Kim, Ian-Woo
2002-01-01
We calculate the full 1-loop corrections to the low energy coupling of bulk gauge boson in a slice of AdS5 which are induced by generic 5-dimensional scalar, Dirac fermion, and vector fields with arbitrary Z_2 times Z_2' orbifold boundary conditions. In supersymmetric limit, our results correctly reproduce the results obtained by an independent method based on 4-dimensional effective supergravity. This provides a nontrivial check of our results and assures the regularization scheme-independen...
Extended Superconformal Algebras on AdS_{3}
Ito, Katsushi
1998-01-01
We study a supersymmetric extension of the Virasoro algebra on the boundary of the anti-de Sitter space-time AdS_{3}. Using the free field realization of the currents, we show that the world-sheet affine Lie superalgebras osp(1|2)^{(1)}, sl(1|2)^{(1)} and sl(2|2)^{(1)} provide the boundary N=1,2 and 4 extended superconformal algebras, respectively.
Universal Kounterterms in Lovelock AdS gravity
Kofinas, Georgios; Olea, Rodrigo
2008-01-01
We show the universal form of the boundary term (Kounterterm series) which regularizes the Euclidean action and background-independent definition of conserved quantities for any Lovelock gravity theory with AdS asymptotics (including Einstein-Hilbert and Einstein-Gauss-Bonnet). We discuss on the connection of this procedure to the existence of topological invariants and Chern-Simons forms in the corresponding dimensions.
Mellin amplitudes for $AdS_5\\times S^5$
Rastelli, Leonardo
2016-01-01
We revisit the calculation of holographic correlation functions in IIB supergravity on $AdS_5\\times S^5$. Results for four-point functions simplify drastically when expressed in Mellin space. We conjecture a compact formula for the four-point functions of one-half BPS singe-trace operators of arbitrary weight. Our methods rely on general consistency conditions and eschew detailed knowledge of the supergravity effective action.
Spectrum and Statistical Entropy of AdS Black Holes
Vaz, Cenalo; Wijewardhana, L. C. R.
2009-01-01
Popular approaches to quantum gravity describe black hole microstates differently and apply different statistics to count them. Since the relationship between the approaches is not clear, this obscures the role of statistics in calculating the black hole entropy. We address this issue by discussing the entropy of eternal AdS black holes in dimension four and above within the context of a midisuperspace model. We determine the black hole eigenstates and find that they describe the quantization...
Alday-Maldacena duality and AdS Plateau problem
Morozov, A.
2008-01-01
A short summary of approximate approach to the study of minimal surfaces in AdS, based on solving Nambu-Goto equations iteratively. Today, after partial denunciation of the BDS conjecture, this looks like the only constructive approach to understanding the ways of its possible modification and thus to saving the Alday-Maldacena duality. Numerous open technical problems are explicitly formulated throughout the text.
Smooth Causal Patches for AdS Black Holes
Raju, Suvrat
2016-01-01
We review the paradox of low energy excitations about an AdS black hole. An appropriately chosen unitary operator in the boundary theory can create a locally strong excitation near the black hole horizon, whose global energy is small as a result of the gravitational redshift. The paradox is that this seems to violate a general rule of statistical mechanics, which states that an operator with energy parametrically smaller than $k T$ cannot create a significant excitation in a thermal system. W...
AdS sub 3 gravity and conformal field theories
Behrndt, K; Gaida, I
1999-01-01
We present a detailed analysis of AdS sub 3 gravity, the BTZ black hole and the associated conformal field theories (CFTs). In particular we focus on the non-extreme six-dimensional string solution with background metric AdS sub 3 x S sup 3 near the horizon. In addition we introduce momentum modes along the string, corresponding to a BTZ black hole, and a Taub-NUT soliton in the transverse Euclidean space. We show that the AdS sub 3 space-time of this configuration has the spatial geometry of an annulus with a Liouville model at the outer boundary and a two-dimensional black hole at the inner boundary. These CFTs provide the dynamical degrees of freedom of the three-dimensional effective model and, together with the CFT corresponding to S sup 3 , provide a statistical interpretation of the corresponding Bekenstein-Hawking entropy. We test the proposed exact black hole entropy, which should hold to all orders in alpha', by an independent field theoretical analysis including higher-order curvature corrections. ...
SUSY properties of warped AdS$_3$
Jeong, Jaehoon; Yoshida, Kentaroh
2014-01-01
We examine supersymmetric properties of null-warped AdS$_3$, or alternatively Schrodinger geometries, dual to putative warped CFTs in two dimensions. We classify super Schrodinger subalgebras of the superalgebra psu(1, 1$|$2) $\\oplus$ psu(1, 1$|$2) , corresponding to the superconformal algebra of the AdS$_3 \\times$ S$^3$ geometry. We comment on geometric realisations and provide a string theory description with enhanced supersymmetry in terms of intersecting D3-branes. For type IIB supergravity solutions based on T$^{1,1}$, we consider the relationship between five-dimensional Schrodinger solutions and their three-dimensional null-warped counterparts, corresponding to R symmetry twists. Finally, we study a family of null-warped AdS$_3$ solutions in a setting where there is an ambiguity over the R symmetry and confirm that, for examples admitting a KK reduction to three dimensions, the minimisation of a real superpotential of the three-dimensional gauged supergravity captures the central charge and R symmetry.
AdS Field Theory from Conformal Field Theory
Fitzpatrick, A Liam
2012-01-01
We provide necessary and sufficient conditions for a Conformal Field Theory to have a description in terms of a perturbative Effective Field Theory in AdS. The first two conditions are well-known: the existence of a perturbative `1/N' expansion and an approximate Fock space of states generated by a finite number of low-dimension operators. We add a third condition, that the Mellin amplitudes of the CFT correlators must be well-approximated by functions that are bounded by a polynomial at infinity in Mellin space, or in other words, that the Mellin amplitudes have an effective theory-type expansion. We explain the relationship between our conditions and unitarity, and provide an analogy with scattering amplitudes that becomes exact in the flat space limit of AdS. The analysis also yields a simple connection between conformal blocks and AdS diagrams, providing a new calculational tool very much in the spirit of the S-Matrix program. We also begin to explore the potential pathologies associated with higher spin ...
Topology Control in VANET and Capacity Estimation
Giang, Anh Tuan; BUSSON, Anthony; Lambert, Alain; Gruyer, Dominique
2013-01-01
Some safety applications using VANET exchange a large amount of data, and consequently require an important network capacity. In this paper, we focus on extended perception map applications, that use information from local and distant sensors to offer driving assistance (autonomous driving, collision warning, etc). Extended perception requires a high bandwidth that might not be available in practice in classical IEEE 802.11p ad hoc networks. Therefore, we propose an adaptive power control alg...
OPEC future capacity expansions
International Nuclear Information System (INIS)
This conference presentation examined OPEC future capacity expansions including highlights from 2000-2004 from the supply perspective and actions by OPEC; OPEC spare capacity in 2005/2006; medium-term capacity expansion and investments; long-term scenarios, challenges and opportunities; and upstream policies in member countries. Highlights from the supply perspective included worst than expected non-OPEC supply response; non-OPEC supply affected by a number of accidents and strikes; geopolitical tensions; and higher than expected demand for OPEC crude. OPEC's actions included closer relationship with other producers and consumers; capacity expansions in 2004 and 2005/2006; and OPEC kept the market well supplied with crude in 2004. The presentation also provided data using graphical charts on OPEC net capacity additions until 2005/2006; OPEC production versus spare capacity from 2003 to 2005; OPEC production and capacity to 2010; and change in required OPEC production from 2005-2020. Medium term expansion to 2010 includes over 60 projects. Medium-term risks such as project execution, financing, costs, demand, reserves, depletion, integration of Iraq, and geopolitical tensions were also discussed. The presentation concluded that in the long term, large uncertainties remain; the peak of world supply is not imminent; and continued and enhanced cooperation is essential to market stability. tabs., figs
DEFF Research Database (Denmark)
Nelson, David W; Murali, Sangita G; Liu, Xiaowen;
2008-01-01
for 48 h and then refed for 2 or 4 days by continuous intravenous or intragastric infusion or ad libitum feeding. Fasting induced significant decreases in body weight, plasma concentrations of IGF-I and bioactive GLP-2, jejunal mucosal cellularity (mass, protein, DNA, and villus height), IGF-I m...... growth and prevented the increase in plasma IGF-I to fed levels; however, plasma GLP-2 and jejunal IGF-I mRNA were restored to fed levels. Intragastric refeeding restored intestinal cellularity and functional capacity (sucrase activity and sodium-glucose transporter-1 expression) to fed levels, whereas...
Reactor lattice transport calculations
International Nuclear Information System (INIS)
The present lecture is a continuation of the lecture on Introduction to the Neutron Transport Phenomena. It comprises three aspects of lattice calculations. First the idea of a reactor lattice is introduced. Then the main definitions used in reactor lattice analysis are given, and finally two basic methods applied for solution of the transport equations are defined. Several remarks on secondary results from lattice transport calculations are added. (author)
Goualard, Jacques; Paugam, D.; Borthomieu, Y.
1993-01-01
The results of tests to assess capacity loss in nickel hydrogen cells are presented in outline form. The effects of long storage (greater than 1 month), high hydrogen pressure storage, high cobalt content, and recovery actions are addressed.
Optimization of ATSC Mobile Handheld Service Capacity
Directory of Open Access Journals (Sweden)
Omneya Issa
2013-01-01
Full Text Available Mobile TV has become a reality offered on several mobile delivery systems. Among them is the Advanced Television System Committee (ATSC system for mobile and handheld digital television services, known as ATSC Mobile DTV or ATSC M/H, which has moved from standardization to implementation. As the North American broadcast industry is preparing to provide Mobile DTV service to consumers, this work discusses important technical parameters that affect the TV service quality and capacity. Since additional error correction mechanisms were added to overcome mobile transmission problems, the available payload for M/H services is limited. This creates a need to efficiently use the available M/H bandwidth. The paper aims to optimize the Mobile DTV service capacity while maintaining an acceptable perceived quality. It presents tradeoffs between several factors affecting service capacity and signal robustness, which is prominent for designing Mobile TV broadcasting scenarios.
O'Farrell, Anthony G.
1991-01-01
Ever since the famous thesis of Frostman, capacities have been important in many areas of function theory. In this talk I shall be concerned only with one–variable function theory on arbitrary open subsets of the complex plane, C. It is important to stress that the open sets need not be connected. I will discuss the use of analytic capacities in connection with problems of removable singularities, holomorphic approximation, and boundary smoothness. A brief reference to the applications ...
Ultraviolet asymptotics and singular dynamics of AdS perturbations
Craps, Ben; Vanhoof, Joris
2015-01-01
Important insights into the dynamics of spherically symmetric AdS-scalar field perturbations can be obtained by considering a simplified time-averaged theory accurately describing perturbations of amplitude epsilon on time-scales of order 1/epsilon^2. The coefficients of the time-averaged equations are complicated expressions in terms of the AdS scalar field mode functions, which are in turn related to the Jacobi polynomials. We analyze the behavior of these coefficients for high frequency modes. The resulting asymptotics can be useful for understanding the properties of the finite-time singularity in solutions of the time-averaged theory recently reported in the literature. We highlight, in particular, the gauge dependence of this asymptotics, with respect to the two most commonly used gauges. The harsher growth of the coefficients at large frequencies in higher-dimensional AdS suggests strengthening of turbulent instabilities in higher dimensions. In the course of our derivations, we arrive at recursive rel...
Directory of Open Access Journals (Sweden)
William A. Brock
2008-12-01
Full Text Available Adaptive capacity is the ability of a living system, such as a social–ecological system, to adjust responses to changing internal demands and external drivers. Although adaptive capacity is a frequent topic of study in the resilience literature, there are few formal models. This paper introduces such a model and uses it to explore adaptive capacity by contrast with the opposite condition, or traps. In a social–ecological rigidity trap, strong self-reinforcing controls prevent the flexibility needed for adaptation. In the model, too much control erodes adaptive capacity and thereby increases the risk of catastrophic breakdown. In a social–ecological poverty trap, loose connections prevent the mobilization of ideas and resources to solve problems. In the model, too little control impedes the focus needed for adaptation. Fluctuations of internal demand or external shocks generate pulses of adaptive capacity, which may gain traction and pull the system out of the poverty trap. The model suggests some general properties of traps in social–ecological systems. It is general and flexible, so it can be used as a building block in more specific and detailed models of adaptive capacity for a particular region.
The creation in the French power system of a capacity mechanism and of a capacity market
International Nuclear Information System (INIS)
The key objective of the French capacity remuneration mechanism is to ensure long term security of supply and to promote peak load containment. The mechanism was set up by the NOME law of December 7, 2010 ('new organisation of the electricity market'), which has changed the organisation of the electricity market and explicitly requires a capacity obligation from suppliers, and by a decree published on December 14, 2012 'concerning the contribution of suppliers to the security of electricity supply and establishing a capacity obligation mechanism in the electricity sector'; further regulation will set up the rules for the capacity mechanism, probably during 2014. The mechanism is decentralized: every supplier has to contribute to supply security and to prove its ability to provide its clients with the capacity they need; all capacity owners in metropolitan France must have their production tools certified. Certificates can be sold and suppliers can buy them to adjust their positions. The transport System operator (TSO) calculates suppliers' obligation, checks if capacity owners fulfil their availability commitment and if suppliers have bought enough certificates. The contribution of interconnections to France's SOS is taken into account implicitly. The decree provides an additional safeguard mechanism, which is centralized: in case a critical situation is observed regarding the electricity supply and demand, the government can organize a call for tender to secure the necessary capacities; the conditions to trigger the call for tender are very restrictive, to ensure the capacity market remains the main investment provider. (author)
TOURISME-TRANSPORT : CAPACITE DE COORDINATION
Marques, Bruno
2016-01-01
Two major findings emerge from the theoretical analysis of Transport-Tourism link via a game theory type model of capacity coordination. Firstly the model explains the optimal capacities ratio of Transport and Tourism by the quotient of the ratio of tourism type (ratio of the length of stay in the destination and of transport duration) divided by the installation costs ratio (of transport and tourism).The corollary of this first finding gives the second outcome: The optimal transport and Tour...
TOURISME-TRANSPORT : CAPACITÉ DE COORDINATION
Marques, Bruno
2016-01-01
Two major findings emerge from the theoretical analysis of Transport-Tourism link via a game theory type model of capacity coordination. Firstly the model explains the optimal capacities ratio of Transport and Tourism by the quotient of the ratio of tourism type (ratio of the length of stay in the destination and of transport duration) divided by the installation costs ratio (of transport and tourism).The corollary of this first finding gives the second outcome: The optimal transport and Tour...
Entanglement Entropy and Duality in AdS(4)
Bakas, Ioannis
2015-01-01
Small variations of the entanglement entropy \\delta S and the expectation value of the modular Hamiltonian \\delta E are computed holographically for circular entangling curves in the boundary of AdS(4), using gravitational perturbations with general boundary conditions in spherical coordinates. Agreement with the first law of thermodynamics, \\delta S = \\delta E, requires that the line element of the entangling curve remains constant. In this context, we also find a manifestation of electric-magnetic duality for the entanglement entropy and the corresponding modular Hamiltonian, following from the holographic energy-momentum/Cotton tensor duality.
Internal Structure of Charged AdS Black Holes
Bhattacharjee, Srijit; Virmani, Amitabh
2016-01-01
When an electrically charged black hole is perturbed its inner horizon becomes a singularity, often referred to as the Poisson-Israel mass inflation singularity. Ori constructed a model of this phenomenon for asymptotically flat black holes, in which the metric can be determined explicitly in the mass inflation region. In this paper we implement the Ori model for charged AdS black holes. We find that the mass function inflates faster than the flat space case as the inner horizon is approached. Nevertheless, the mass inflation singularity is still a weak singularity: although spacetime curvature becomes infinite, tidal distortions remain finite on physical objects attempting to cross it.
The AdS3 central charge in string theory
International Nuclear Information System (INIS)
We evaluate the vacuum expectation value of the central charge operator in string theory in an AdS3 vacuum. Our calculation provides a rare non-zero one-point function on a spherical worldsheet. The evaluation involves the regularization both of a worldsheet ultraviolet divergence (associated to the infinite volume of the conformal Killing group), and a space-time infrared divergence (corresponding to the infinite volume of space-time). The two divergences conspire to give a finite result, which is the classical general relativity value for the central charge, corrected in bosonic string theory by an infinite series of tree level higher derivative terms.
Small black holes in global AdS spacetime
Jokela, Niko; Pönni, Arttu; Vuorinen, Aleksi
2016-04-01
We study the properties of two-point functions and quasinormal modes in a strongly coupled field theory holographically dual to a small black hole in global anti-de Sitter spacetime. Our results are seen to smoothly interpolate between known limits corresponding to large black holes and thermal AdS space, demonstrating that the Son-Starinets prescription works even when there is no black hole in the spacetime. Omitting issues related to the internal space, the results can be given a field theory interpretation in terms of the microcanonical ensemble, which provides access to energy densities forbidden in the canonical description.
Self-Dual Warped AdS$_3$ Black Holes
Chen, Bin; Ning, Bo
2010-01-01
We propose a new class of solutions of three-dimensional topological massive gravity. These solutions are non-extremal black holes, with their extremal counterparts being discrete quotients of spacelike warped AdS$_3$ along the $U(1)_L$ isometry. We study the thermodynamics of these black holes and show that the first law is satisfied. We also show that for consistent boundary conditions, the asymptotic symmetry generators form only one copy of the Virasoro algebra with central charge $c_L = \\frac{4\
Thermal Fluctuations in a Charged AdS Black Hole
Pourhassan, B
2015-01-01
In this paper, we will analyze the effects of thermal fluctuations on a charged AdS black hole. This will be done by analyzing the corrections to black hole thermodynamics due to these thermal fluctuations. We will demonstrate that the entropy of this black hole get corrected by logarithmic term. We will also calculate other corrections to other important thermodynamic quantities for this black hole. Finally, we will use the corrected value of the specific heat to analyze the phase transition in this system.
Most general AdS_3 boundary conditions
Grumiller, Daniel
2016-01-01
We consider the most general asymptotically anti-de Sitter boundary conditions in three-dimensional Einstein gravity with negative cosmological constant. The metric contains in total twelve independent functions, six of which are interpreted as chemical potentials (or non-normalizable fluctuations) and the other half as canonical boundary charges (or normalizable fluctuations). Their presence modifies the usual Fefferman-Graham expansion. The asymptotic symmetry algebra consists of two sl(2)_k current algebras, the levels of which are given by k=l/(4G_N), where l is the AdS radius and G_N the three-dimensional Newton constant.
AdS Chern-Simons Gravity induces Conformal Gravity
Aros, Rodrigo
2013-01-01
The leitmotif of this paper is the question of whether four- and higher even-dimensional Conformal Gravities do have a Chern-Simons pedigree. We show that Weyl gravity can be obtained as dimensional reduction of a five-dimensional Chern-Simons action for a suitable (gauged-fixed, tractor-like) five-dimensional AdS connection. The gauge-fixing and dimensional reduction program admits a readily generalization to higher dimensions for the case of certain conformal gravities obtained by contractions of the Weyl tensor.
Belin, Alexandre; Hung, Ling-Yan
2015-01-01
We discuss properties of interpolating geometries in three dimensional gravity in the presence of a chiral anomaly. This anomaly, which introduces an unbalance between left and right central charges, is protected under RG flows. For this simple reason it is impossible to gap a system with such an anomaly. Our goal is to discuss how holography captures this basic and robust feature. We demonstrate the absence of a mass gap by analysing the linearized spectrum and holographic entanglement entropy of these backgrounds in the context of AdS$_3$/CFT$_2$.
Internal Structure of Charged AdS Black Holes
Bhattacharjee, Srijit(Astroparticle Physics & Cosmology Division, Saha Institute of Nuclear Physics, Kolkata, 700064, India); Sarkar, Sudipta; Virmani, Amitabh
2016-01-01
When an electrically charged black hole is perturbed its inner horizon becomes a singularity, often referred to as the Poisson-Israel mass inflation singularity. Ori constructed a model of this phenomenon for asymptotically flat black holes, in which the metric can be determined explicitly in the mass inflation region. In this paper we implement the Ori model for charged AdS black holes. We find that the mass function inflates faster than the flat space case as the inner horizon is approached...
Pure Spinors in AdS and Lie Algebra Cohomology
Mikhailov, Andrei
2014-10-01
We show that the BRST cohomology of the massless sector of the Type IIB superstring on AdS5 × S 5 can be described as the relative cohomology of an infinite-dimensional Lie superalgebra. We explain how the vertex operators of ghost number 1, which correspond to conserved currents, are described in this language. We also give some algebraic description of the ghost number 2 vertices, which appears to be new. We use this algebraic description to clarify the structure of the zero mode sector of the ghost number two states in flat space, and initiate the study of the vertices of the higher ghost number.
COSCO Calls for Boost of China's Oil Fleet Capacity
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
@@ Dalian Ocean Shipping Company (COSCO Dalian)said recently that China should strengthen its maritime oil transport capacity to ensure the security of China's oil supply. Meng Qinglin, Managing Director of COSCO Dalian, said at the 2006 China Oil and Gas Summit that with the rise of China's oil imports, the weak maritime oil transport capacity has become a major threat to China's oil supply security.
ADS National Programmes: Russian Federation
International Nuclear Information System (INIS)
Studies on accelerator driven systems (ADS), which be used as burners of long lived radioactive waste accrued due to operation of thermal reactors, first of all, minor actinides (MA), are carried out in some Russian research institutes (ITEP, SSC RF - IPPE, VNIIEF, JINR, RSC KI, IYaI RAN, OKB ‘GIDROPRESS’, VNIITF etc.). These researches are mainly connected with studying physical processes existing in ADS and their parameters and with design studies and substantiation of experimental ADS facilities. One of the most important directions of researches is the acquirement of quite precise and reliable nuclear data on MA with reference to conditions existing in ADS. Now a coordinated programme of researches on measurement and estimation of nuclear data for 22 isotopes of U, Pu, Np, Am, Cm, Bk and Cf in neutron energy range from 0.05 eV up to 30 MeV has been prepared. Development of different variants of ADS has put a task of comparison of their efficiency as burners of MA
Accomazzi, Alberto; Kurtz, M. J.; Henneken, E. A.; Grant, C. S.; Thompson, D.; Luker, J.; Chyla, R.; Murray, S. S.
2014-01-01
In the spring of 1993, the Smithsonian/NASA Astrophysics Data System (ADS) first launched its bibliographic search system. It was known then as the ADS Abstract Service, a component of the larger Astrophysics Data System effort which had developed an interoperable data system now seen as a precursor of the Virtual Observatory. As a result of the massive technological and sociological changes in the field of scholarly communication, the ADS is now completing the most ambitious technological upgrade in its twenty-year history. Code-named ADS 2.0, the new system features: an IT platform built on web and digital library standards; a new, extensible, industrial strength search engine; a public API with various access control capabilities; a set of applications supporting search, export, visualization, analysis; a collaborative, open source development model; and enhanced indexing of content which includes the full-text of astronomy and physics publications. The changes in the ADS platform affect all aspects of the system and its operations, including: the process through which data and metadata are harvested, curated and indexed; the interface and paradigm used for searching the database; and the follow-up analysis capabilities available to the users. This poster describes the choices behind the technical overhaul of the system, the technology stack used, and the opportunities which the upgrade is providing us with, namely gains in productivity and enhancements in our system capabilities.
On thermodynamics of charged AdS black holes in extended phases space via M2-branes background
Chabab, M.; El Moumni, H.; Masmar, K.
2016-06-01
Motivated by a recent work on asymptotically AdS_4 black holes in M-theory, we investigate both thermodynamics and the thermodynamical geometry of Reissner-Nordstrom-AdS black holes from M2-branes. More precisely, we study AdS black holes in AdS4× S7, with the number of M2-branes interpreted as a thermodynamical variable. In this context, we calculate various thermodynamical quantities including the chemical potential, and examine their phase transitions along with the corresponding stability behaviors. In addition, we also evaluate the thermodynamical curvatures of the Weinhold, Ruppeiner, and Quevedo metrics for M2-branes geometry to study the stability of such a black object. We show that the singularities of these scalar curvature's metrics reproduce similar stability results to those obtained by the phase transition diagram via the heat capacities in different ensembles either when the number of the M2 branes or the charge is held fixed. Also, we note that all results derived in Belhaj et al. (Eur Phys J C 76(2):73, 2016) are recovered in the limit of the vanishing charge.
Thermodynamics of Charged AdS Black Holes in Extended Phases Space via M2-branes Background
Chabab, M; Masmar, K
2015-01-01
Motivated by a recent work on asymptotically Ad$S_4$ black holes in M-theory, we investigate both thermodynamics and thermodynamical geometry of Raissner-Nordstrom-AdS black holes from M2-branes. More precisely, we study AdS black holes in $AdS_{4}\\times S^{7}$, with the number of M2-branes interpreted as a thermodynamical variable. In this context, we calculate various thermodynamical quantities including the chemical potential, and examine their phase transitions along with the corresponding stability behaviors. In addition, we also evaluate the thermodynamical curvatures of the Weinhold, Ruppeiner and Quevedo metrics for M2-branes geometry to study the stability of such black object. We show that the singularities of these scalar curvature's metrics reproduce similar stability results obtained by the phase transition program via the heat capacities in different ensembles either when the number of the M2 branes or the charge are held fixed. Also, we note that all results derived in [1] are recovered in the ...
Light dependence of carboxylation capacity for C3 photosynthesis models
Photosynthesis at high light is often modelled by assuming limitation by the maximum capacity of Rubisco carboxylation at low carbon dioxide concentrations, by electron transport capacity at higher concentrations, and sometimes by triose-phosphate utilization rate at the highest concentrations. Pho...
AdCell: Ad Allocation in Cellular Networks
Alaei, Saeed; Liaghat, Vahid; Pei, Dan; Saha, Barna
2011-01-01
With more than four billion usage of cellular phones worldwide, mobile advertising has become an attractive alternative to online advertisements. In this paper, we propose a new targeted advertising policy for Wireless Service Providers (WSPs) via SMS or MMS- namely {\\em AdCell}. In our model, a WSP charges the advertisers for showing their ads. Each advertiser has a valuation for specific types of customers in various times and locations and has a limit on the maximum available budget. Each query is in the form of time and location and is associated with one individual customer. In order to achieve a non-intrusive delivery, only a limited number of ads can be sent to each customer. Recently, new services have been introduced that offer location-based advertising over cellular network that fit in our model (e.g., ShopAlerts by AT&T) . We consider both online and offline version of the AdCell problem and develop approximation algorithms with constant competitive ratio. For the online version, we assume tha...
No Holography for Eternal AdS Black Holes
Avery, Steven G
2013-01-01
It is generally believed that the eternal AdS black hole is dual to two conformal field theories with compact spatial sections that are together in a thermofield double state. We argue that this proposal is incorrect, and by extension so are the "entanglement=geometry" proposal of Van Raamsdonk and "ER=EPR" proposal of Maldacena and Susskind. We show that in the bulk there is an interaction needed between the two halves of the Hilbert space for connectivity across the horizon; however, there is no such interaction between the CFTs. This rules out the possibility of the dual to the CFTs being the eternal AdS black hole. We argue the correct dual "geometries" resemble the exterior of the black hole outside the stretched horizon but cap off before the global horizon. This disallows the possibility of a shared future (and past) wedge where Alice falling from one side can meet Bob falling from the other. We expect that in the UV complete theory the aforementioned caps will be fuzzballs.
AdS Twistors for Higher Spin Theory
International Nuclear Information System (INIS)
We construct spectra of supersymmetric higher spin theories in D = 4, 5 and 7 from twistors describing massless (super-)particles on AdS spaces. A massless twistor transform is derived in a geometric way from classical kinematics. Relaxing the spin-shell constraints on twistor space gives an infinite tower of massless states of a 'higher spin particle', generalizing previous work of Bandos et al.. This can generically be done in a number of ways, each defining the states of a distinct higher spin theory, and the method provides a systematic way of finding these. We reproduce known results in D = 4, minimal supersymmetric 5- and 7-dimensional models, as well as supersymmetrisations of Vasiliev's Sp-models as special cases. In the latter models a dimensional enhancement takes place, meaning that the theory lives on a space of higher dimension than the original AdS space, and becomes a theory of doubletons. This talk was presented at the XIX-th Max Born Symposium 'Fundamental Interactions and Twistor-Like Methods', September 2004, in Wroclaw, Poland
Bi-Local Fields in AdS${}_5$ Spacetime
Aouda, Kenichi; Toyoda, Haruki
2016-01-01
Recently, the bi-local fields attracts the interest in studying the duality between $O(N)$ vector model and a higher-spin gauge theory in $AdS$ spacetime. In those theories, the bi-local fields are realized as collective one's of the $O(N)$ vector fields, which are the source of higher spin bulk fields. Historically, the bi-local fields are introduced as a candidate of non-local fields by Yukawa. Today, Yukawa's bi-local fields are understood from a viewpoint of relativistic two-particle bound systems, the bi-local systems. We study the relation between the collective bi-local fields out of HS bulk fields and the fields out of bi-local systems embedded in AdS${}_5$ spacetime with warped metric. It is shown that the effective spring tension of the bi-local system depends on the brane, on which the bi-local system is located. In paticular, a tensionless bi-local sytem, being similar to the collective bi-local fields, can be realized on a low-energy visible brane.
Smooth Causal Patches for AdS Black Holes
Raju, Suvrat
2016-01-01
We review the paradox of low energy excitations about an AdS black hole. An appropriately chosen unitary operator in the boundary theory can create a locally strong excitation near the black hole horizon, whose global energy is small as a result of the gravitational redshift. The paradox is that this seems to violate a general rule of statistical mechanics, which states that an operator with energy parametrically smaller than $k T$ cannot create a significant excitation in a thermal system. When we carefully examine the position dependence of the boundary unitary operator that produces the excitation and the bulk observable necessary to detect the anomalously large effect, we find that they do not both fit in a single causal patch. This follows from a remarkable property of position space AdS correlators that we establish explicitly, and resolves the paradox in a generic state of the system, since no combination of observers can both create the excitation and observe its effect. As a special case of our analy...
Conserved charges in timelike warped AdS3 spaces
Donnay, L.; Fernández-Melgarejo, J. J.; Giribet, G.; Goya, A.; Lavia, E.
2015-06-01
We consider the timelike version of warped anti-de Sitter space (WAdS), which corresponds to the three-dimensional section of the Gödel solution of four-dimensional cosmological Einstein equations. This geometry presents closed timelike curves (CTCs), which are inherited from its four-dimensional embedding. In three dimensions, this type of solution can be supported without matter provided the graviton acquires mass. Here, among the different ways to consistently give mass to the graviton in three dimensions, we consider the parity-even model known as new massive gravity (NMG). In the bulk of timelike WAdS3 space, we introduce defects that, from the three-dimensional point of view, represent spinning massive particlelike objects. For this type of source, we investigate the definition of quasilocal gravitational energy as seen from infinity, far beyond the region where the CTCs appear. We also consider the covariant formalism applied to NMG to compute the mass and the angular momentum of spinning particlelike defects and compare the result with the one obtained by means of the quasilocal stress tensor. We apply these methods to special limits in which the WAdS3 solutions coincide with locally AdS3 and locally AdS2×R spaces. Finally, we make some comments about the asymptotic symmetry algebra of asymptotically WAdS3 spaces in NMG.
The CFT dual of AdS gravity with torsion
International Nuclear Information System (INIS)
We consider the Mielke-Baekler model of three-dimensional AdS gravity with torsion, which has gravitational and translational Chern-Simons terms in addition to the usual Einstein-Hilbert action with cosmological constant. It is shown that the topological nature of the model leads to a finite Fefferman-Graham expansion. We derive the holographic stress tensor and the associated Ward identities and show that, due to the asymmetry of the left- and right-moving central charges, a Lorentz anomaly appears in the dual conformal field theory. Both the consistent and the covariant Weyl and Lorentz anomaly are determined, and the Wess-Zumino consistency conditions for the former are verified. Moreover we consider the most general solution with flat boundary geometry, which describes left- and right-moving gravitational waves on AdS3 with torsion, and show that in this case the holographic energy-momentum tensor is given by the wave profiles. The anomalous transformation laws of the wave profiles under diffeomorphisms preserving the asymptotic form of the bulk solution yield the central charges of the dual CFT and confirm the results that appeared earlier on in the literature. Finally we comment on some points concerning the microstate counting for the Riemann-Cartan black hole
Quantum cat map dynamics on AdS$_2$
Axenides, Minos; Nicolis, Stam
2016-01-01
We present a toy model for the chaotic unitary scattering of single particle wave packets on the radial AdS$_2$ geometry of extremal BH horizons. Based on our recent work for the discretization of the AdS$_2$ space-time, which describes a finite and random geometry, by modular arithmetic, we investigate the validity of the eigenstate thermalization hypothesis (ETH), as well as that of the fast scrambling time bound conjecture (STB), for an observer with time evolution operator the quantum Arnol'd cat map (QACM). We find that the QACM, while possessing a linear spectrum, has eigenstates, which can be expressed in closed form, are found to be random and to satisfy the assumptions of the ETH.The implications are that the dynamics is described by a chaotic, unitary, single particle S-matrix, which completely delocalizes and randomizes initial gaussian wave packets . Applying results obtained by Dyson and Falk for the periods of the Arnol'd Cat Map(ACM),which are related to its mixing time, we also find that the t...
Greig, Jenny A; Buckley, Suzanne Mk; Waddington, Simon N; Parker, Alan L; Bhella, David; Pink, Rebecca; Rahim, Ahad A; Morita, Takashi; Nicklin, Stuart A; McVey, John H; Baker, Andrew H
2009-10-01
The binding of coagulation factor X (FX) to the hexon of adenovirus (Ad) 5 is pivotal for hepatocyte transduction. However, vectors based on Ad35, a subspecies B Ad, are in development for cancer gene therapy, as Ad35 utilizes CD46 (which is upregulated in many cancers) for transduction. We investigated whether interaction of Ad35 with FX influenced vector tropism using Ad5, Ad35, and Ad5/Ad35 chimeras: Ad5/fiber(f)35, Ad5/penton(p)35/f35, and Ad35/f5. Surface plasmon resonance (SPR) revealed that Ad35 and Ad35/f5 bound FX with approximately tenfold lower affinities than Ad5 hexon-containing viruses, and electron cryomicroscopy (cryo-EM) demonstrated a direct Ad35 hexon:FX interaction. The presence of physiological levels of FX significantly inhibited transduction of vectors containing Ad35 fibers (Ad5/f35, Ad5/p35/f35, and Ad35) in CD46-positive cells. Vectors were intravenously administered to CD46 transgenic mice in the presence and absence of FX-binding protein (X-bp), resulting in reduced liver accumulation for all vectors. Moreover, Ad5/f35 and Ad5/p35/f35 efficiently accumulated in the lung, whereas Ad5 demonstrated poor lung targeting. Additionally, X-bp significantly reduced lung genome accumulation for Ad5/f35 and Ad5/p35/f35, whereas Ad35 was significantly enhanced. In summary, vectors based on the full Ad35 serotype will be useful vectors for selective gene transfer via CD46 due to a weaker FX interaction compared to Ad5. PMID:19603000
Online Ad Slotting With Cancellations
Constantin, Florin; Muthukrishnan, S; Pal, Martin
2008-01-01
Many advertisers buy advertisements (ads) on the Internet or on traditional media and seek simple, online mechanisms to reserve ad slots in advance. Media publishers represent a vast and varying inventory, and they too seek automatic, online mechanisms for pricing and allocating such reservations. In this paper, we present and study a simple model for auctioning such ad slots in advance. Bidders arrive sequentially and report which slots they are interested in. The seller must decide immediately whether or not to grant a reservation. Our model allows a seller to accept reservations, but possibly cancel the allocations later and pay the bidder a cancellation compensation (bump payment). Our main result is an online mechanism to derive prices and bump payments that is efficient to implement. This mechanism has many desirable properties. It is individually rational; winners have an incentive to be honest and bidding one's true value dominates any lower bid. Our mechanism's efficiency is within a constant fractio...
Performance Analysis of Ad Hoc Dispersed Spectrum Cognitive Radio Networks over Fading Channels
Directory of Open Access Journals (Sweden)
Mohammad Muneer
2011-01-01
Full Text Available Cognitive radio systems can utilize dispersed spectrum, and thus such approach is known as dispersed spectrum cognitive radio systems. In this paper, we first provide the performance analysis of such systems over fading channels. We derive the average symbol error probability of dispersed spectrum cognitive radio systems for two cases, where the channel for each frequency diversity band experiences independent and dependent Nakagami- fading. In addition, the derivation is extended to include the effects of modulation type and order by considering M-ary phase-shift keying ( -PSK and M-ary quadrature amplitude modulation -QAM schemes. We then consider the deployment of such cognitive radio systems in an ad hoc fashion. We consider an ad hoc dispersed spectrum cognitive radio network, where the nodes are assumed to be distributed in three dimension (3D. We derive the effective transport capacity considering a cubic grid distribution. Numerical results are presented to verify the theoretical analysis and show the performance of such networks.
Optimal Routing and Power Control for a Single Cell, Dense, Ad Hoc Wireless Network
Ramaiyan, Venkatesh; Altman, Eitan
2009-01-01
We consider a dense, ad hoc wireless network, confined to a small region. The wireless network is operated as a single cell, i.e., only one successful transmission is supported at a time. Data packets are sent between sourcedestination pairs by multihop relaying. We assume that nodes self-organise into a multihop network such that all hops are of length d meters, where d is a design parameter. There is a contention based multiaccess scheme, and it is assumed that every node always has data to send, either originated from it or a transit packet (saturation assumption). In this scenario, we seek to maximize a measure of the transport capacity of the network (measured in bit-meters per second) over power controls (in a fading environment) and over the hop distance d, subject to an average power constraint. We first argue that for a dense collection of nodes confined to a small region, single cell operation is efficient for single user decoding transceivers. Then, operating the dense ad hoc wireless network (desc...
International Nuclear Information System (INIS)
We present a LEU-ADS design based on an existing Argentine experimental facility, the RA-8 pool type zero power reactor. The versatility of this reactor allows measurement of different core configurations using different fuel enrichment, burnable poison rods, water perturbations and different control rods types in critical or subcritical configurations with an external source. To assess the feasibility of the LEU-ADS, multiplication factors, kinetic parameters, spectra, and time flux evolution were computed. Two external sources were considered: an isotopic 252Cf source, and a D-D pulsed neutron source. Parameters for different core configurations were calculated, and the feasibility of using continuous and pulsed neutron sources was verified.
International Nuclear Information System (INIS)
Conclusions: • The YALINA facility is a unique installation which was designed as a zero power model of real ADS. • It is intended to study neutronics and kinetics of the sub-critical reactors driven by external neutron sources. • The successful operation of this facility is a scientific contribution from the Republic of Belarus, as well as the international team from EC and USA. • The experimental data are used to benchmark and validate methods and computer codes for designing and licensing ADS
Dual capacity reciprocating compressor
Wolfe, Robert W.
1984-01-01
A multi-cylinder compressor 10 particularly useful in connection with northern climate heat pumps and in which different capacities are available in accordance with reversing motor 16 rotation is provided with an eccentric cam 38 on a crank pin 34 under a fraction of the connecting rods, and arranged for rotation upon the crank pin between opposite positions 180.degree. apart so that with cam rotation on the crank pin such that the crank throw is at its normal maximum value all pistons pump at full capacity, and with rotation of the crank shaft in the opposite direction the cam moves to a circumferential position on the crank pin such that the overall crank throw is zero. Pistons 24 whose connecting rods 30 ride on a crank pin 36 without a cam pump their normal rate with either crank rotational direction. Thus a small clearance volume is provided for any piston that moves when in either capacity mode of operation.
Geothermal Plant Capacity Factors
Energy Technology Data Exchange (ETDEWEB)
Greg Mines; Jay Nathwani; Christopher Richard; Hillary Hanson; Rachel Wood
2015-01-01
The capacity factors recently provided by the Energy Information Administration (EIA) indicated this plant performance metric had declined for geothermal power plants since 2008. Though capacity factor is a term commonly used by geothermal stakeholders to express the ability of a plant to produce power, it is a term frequently misunderstood and in some instances incorrectly used. In this paper we discuss how this capacity factor is defined and utilized by the EIA, including discussion on the information that the EIA requests from operations in their 923 and 860 forms that are submitted both monthly and annually by geothermal operators. A discussion is also provided regarding the entities utilizing the information in the EIA reports, and how those entities can misinterpret the data being supplied by the operators. The intent of the paper is to inform the facility operators as the importance of the accuracy of the data that they provide, and the implications of not providing the correct information.
DEFF Research Database (Denmark)
Jensen, Thomas Christian
2014-01-01
The paper presents estimations of the effect of bad weather on the observed speed on a Danish highway section; Køge Bugt Motorvejen. The paper concludes that weather, primarily precipitation and snow, has a clear negative effect on speed when the road is not in hypercongestion mode. Furthermore......, the capacity of the highway seems to be reduced in bad weather and there are indications that travel time variability is also increased, at least in free-flow conditions. Heavy precipitation reduces speed and capacity by around 5-8%, whereas snow primarily reduces capacity. Other weather variables......-parametrically against traffic density and in step 2 the residuals from step 1 are regressed linearly against the weather variables. The choice of a non-parametric method is made to avoid constricting ties from a parametric specification and because the focus here is not on the relationship between traffic flow...
Capacity Maximizing Constellations
Barsoum, Maged; Jones, Christopher
2010-01-01
Some non-traditional signal constellations have been proposed for transmission of data over the Additive White Gaussian Noise (AWGN) channel using such channel-capacity-approaching codes as low-density parity-check (LDPC) or turbo codes. Computational simulations have shown performance gains of more than 1 dB over traditional constellations. These gains could be translated to bandwidth- efficient communications, variously, over longer distances, using less power, or using smaller antennas. The proposed constellations have been used in a bit-interleaved coded modulation system employing state-ofthe-art LDPC codes. In computational simulations, these constellations were shown to afford performance gains over traditional constellations as predicted by the gap between the parallel decoding capacity of the constellations and the Gaussian capacity
Revisiting Absorptive Capacity
DEFF Research Database (Denmark)
de Araújo, Ana Luiza Lara; Ulhøi, John Parm; Lettl, Christopher
Absorptive capacity has mostly been perceived as a 'passive' outcome of R&D investments. Recently, however, a growing interest into its 'proactive' potentials has emerged. This paper taps into this development and proposes a dynamic model for conceptualizing the determinants of the complementary...... learning processes of absorptive capacity, which comprise combinative and adaptive capabilities. Drawing on survey data (n=169), the study concludes that combinative capabilities primarily enhance transformative and exploratory learning processes, while adaptive capabilities strengthen all three learning...... processes, with emphasis on exploitative learning. Before concluding, the paper addresses implications for theory and practice and limitations of this study....
Directory of Open Access Journals (Sweden)
F. Hamzezadeh
2014-01-01
Full Text Available In many systems such as computer network, fuel distribution, and transportation system, it is necessary to change the capacity of some arcs in order to increase maximum flow value from source s to sink t, while the capacity change incurs minimum cost. In real-time networks, some factors cause loss of arc’s flow. For example, in some flow distribution systems, evaporation, erosion or sediment in pipes waste the flow. Here we define a real capacity, or the so-called functional capacity, which is the operational capacity of an arc. In other words, the functional capacity of an arc equals the possible maximum flow that may pass through the arc. Increasing the functional arcs capacities incurs some cost. There is a certain resource available to cover the costs. First, we construct a mathematical model to minimize the total cost of expanding the functional capacities to the required levels. Then, we consider the loss of flow on each arc as a stochastic variable and compute the system reliability.
Problems Of Transport Energetics In Lithuania
International Nuclear Information System (INIS)
Lithuania has more than one million of transport means, the thermal capacity of which is about 50 mill. kW, i.e. 10 times more than the capacity of all thermal power stations. In the 21st century electrical energy will be used for transport means instead of petrol, and new capacities of electric stations in Lithuania will be necessary. All perspective transport means are described and conclusions for Lithuanian energetics are presented. (author)
Holographic properties in three-dimensional AdS soliton using $AdS_3/CFT_2$
Peng, Yan
2016-01-01
We study the holographic description of a superconductor by the $AdS_{3}/CFT_{2}$ correspondence. The system is constructed with a Maxwell field and a charged scalar field coupled in the (2+1)-dimensional AdS soliton background. With analytical methods, we obtain the exact expression for the critical chemical potential as $\\mu_{c} = 1 + \\sqrt{1+m^2}$, which has also been generalized to higher dimensions as $\\mu_c \\thickapprox a + \\sqrt{m^2-m_{BF}^2}$ in this work. Around the phase transition points, we find a correspondence between the value of the scalar field at the tip and the scalar operator at infinity. We also arrive at the classical second order phase transition threshold exponent $\\beta=\\frac{1}{2}$ as the same as the mean field theory near the critical chemical potential. As the condensation becomes heavier, we show surprisingly that superconducting phases exist only in a certain range of the chemical potential, which is very different from higher-dimensional cases. And for the small enough negative ...
D. David (David); L.F. Hoogerheide (Lennart); H.K. van Dijk (Herman)
2008-01-01
textabstractThis short note presents the R package AdMit which provides flexible functions to approximate a certain target distribution and it provides an efficient sample of random draws from it, given only a kernel of the target density function. The estimation procedure is fully automatic and thu
An Overview of Local Capacity in Wireless Networks
Malik, Salman
2012-01-01
This article introduces a metric for performance evaluation of medium access schemes in wireless ad hoc networks known as local capacity. Although deriving the end-to-end capacity of wireless ad hoc networks is a difficult problem, the local capacity framework allows us to quantify the average information rate received by a receiver node randomly located in the network. In this article, the basic network model and analytical tools are first discussed and applied to a simple network to derive the local capacity of various medium access schemes. Our goal is to identify the most optimal scheme and also to see how does it compare with more practical medium access schemes. We analyzed grid pattern schemes where simultaneous transmitters are positioned in a regular grid pattern, ALOHA schemes where simultaneous transmitters are dispatched according to a uniform Poisson distribution and exclusion schemes where simultaneous transmitters are dispatched according to an exclusion rule such as node coloring and carrier s...
Electro-stimulated microbial factory for value added product synthesis.
Roy, Shantonu; Schievano, Andrea; Pant, Deepak
2016-08-01
Interplay of charge between bacteria and electrode has led to emergence of bioelectrochemical systems which leads to applications such as production of electricity, wastewater treatment, bioremediation and production of value added products. Many electroactive bacteria have been identified that have unique external electron transport systems. Coupling of electron transport with carbon metabolism has opened a new approach of carbon dioxide sequestration. The electron transport mechanism involves various cellular and sub cellular molecules. The outer membrane cytochromes, Mtr-complex and Ech-complex are few key molecules involved in electron transport in many electrogenic bacteria. Few cytochrome independent acetogenic electroactive bacteria were also discovered using Rnf complex to transport electrons. For improved productivity, an efficient bioreactor design is mandatory. It should encompass all certain critical issues such as microbial cell retention, charge dissipation, separators and simultaneous product recovery. PMID:27034155
Vedr.: Military capacity building
DEFF Research Database (Denmark)
Larsen, Josefine Kühnel; Struwe, Lars Bangert
2013-01-01
Kühnel Larsen and researcher Lars Bangert Struwe of CMS had organized a seminar in collaboration with Royal Danish Defense Colleg and the East African Security Governance Network. The seminar focused on some of the risks involved in Military capacity building and how these risks are dealt with from...
Discontinuous symplectic capacities
Zehmisch, Kai; Ziltener, Fabian
2012-01-01
Comment: We include generalizations to higher dimensions due to the unknown referee and Janko Latschev. We add examples of open sets with connected boundary on which the shell capacity is not continuous. 3rd and 4th version: minor changes, to appear in J. Fixed Point Theory Appl
DEFF Research Database (Denmark)
Habekost, Thomas; Starrfelt, Randi
2009-01-01
Psychophysical studies have identified two distinct limitations of visual attention capacity: processing speed and apprehension span. Using a simple test, these cognitive factors can be analyzed by Bundesen's Theory of Visual Attention (TVA). The method has strong specificity and sensitivity, and...
Zhou, Xuemei; Huang, Huang; Jia, Xinchang; Jiang, Nan
2014-11-01
Forecasting the demand of an integrated passenger terminal under the capacity constraints of its surrounding roads has always been a challenging problem for urban transportation terminals planning and construction in China. A bi-level model is proposed to forecast the passenger demand of an integrated terminal, whose throughput is restricted by the capacity of its surrounding road network. The upper level model maximizes the passenger flow of a terminal considering the capacity constraints of its surrounding road network. The User Equilibrium (UE) model is adopted as lower level model for traffic assignment. The adaptive genetic algorithm (AGA) is applied to solve this bi-level problem. The West-Lanzhou integrated passenger terminal in the Lanzhou city of China is used to test the feasibility and effectiveness of the proposed model. Test results show that, to reduce traffic congestion at the terminal, priority should be given to transportation mode with higher performance.
An Investigation of AdS2 Backreaction and Holography
Engelsöy, Julius; Verlinde, Herman
2016-01-01
We investigate a dilaton gravity model in AdS2 proposed by Almheiri and Polchinski and develop an 1D effective description in terms of a dynamical boundary time with a Schwarzian derivative action. We show that the effective model is equivalent to a 1D version of Liouville theory, and investigate its dynamics and symmetries via a standard canonical framework. We include the coupling to arbitrary conformal matter and analyze the effective action in the presence of possible sources. We compute commutators of local operators at large time separation, and match the result with the time shift due to a gravitational shockwave interaction. We study a black hole evaporation process and comment on the role of entropy in this model.
On jordanian deformations of AdS_5 and supergravity
Hoare, Ben
2016-01-01
We consider various homogeneous Yang-Baxter deformations of the AdS_5 x S^5 superstring that can be obtained from the eta-deformed superstring and related models by singular boosts. The jordanian deformations we obtain in this way behave similarly to the eta-deformed model with regard to supergravity: T dualizing the classical sigma model it is possible to find corresponding solutions of supergravity, which, however, have dilatons that prevent T dualizing back. Hence the backgrounds of these jordanian deformations are not solutions of supergravity. Still, they do satisfy a set of recently found modified supergravity equations which should imply that the corresponding sigma models are scale invariant. The abelian models that we obtain by singular boosts do directly correspond to solutions of supergravity. In addition to our main results we consider contraction limits of our main example, which also do not correspond to supergravity solutions.
Colliding waves on a string in AdS$_3$
Vegh, David
2015-01-01
This paper is concerned with the classical motion of a string in global AdS$_3$. The initially static string stretches between two antipodal points on the boundary circle. Both endpoints are perturbed which creates cusps at a steady rate. The cusps propagate towards the interior where they collide. The behavior of the string depends on the strength of forcing. Three qualitatively different phases can be distinguished: transparent, gray, and black. The transparent region is analogous to a standing wave. In the black phase, there is a horizon on the worldsheet and cusps never reach the other endpoint. The string keeps folding and its length grows linearly over time. In the gray phase, the string still grows linearly. However, cusps do cross to the other side. The transparent and gray regions are separated by a transition point where a logarithmic accumulation of cusps is numerically observed. A simple model reproduces the qualitative behavior of the string in the three phases.
Thermodynamics of charged Lovelock: AdS black holes
Energy Technology Data Exchange (ETDEWEB)
Prasobh, C.B.; Suresh, Jishnu; Kuriakose, V.C. [Cochin University of Science and Technology, Department of Physics, Cochin (India)
2016-04-15
We investigate the thermodynamic behavior of maximally symmetric charged, asymptotically AdS black hole solutions of Lovelock gravity. We explore the thermodynamic stability of such solutions by the ordinary method of calculating the specific heat of the black holes and investigating its divergences which signal second-order phase transitions between black hole states. We then utilize the methods of thermodynamic geometry of black hole spacetimes in order to explain the origin of these points of divergence. We calculate the curvature scalar corresponding to a Legendre-invariant thermodynamic metric of these spacetimes and find that the divergences in the black hole specific heat correspond to singularities in the thermodynamic phase space. We also calculate the area spectrum for large black holes in the model by applying the Bohr-Sommerfeld quantization to the adiabatic invariant calculated for the spacetime. (orig.)
The Analytic Bootstrap and AdS Superhorizon Locality
Fitzpatrick, A Liam; Poland, David; Simmons-Duffin, David
2012-01-01
We take an analytic approach to the CFT bootstrap, studying the 4-pt correlators of d > 2 dimensional CFTs in an Eikonal-type limit, where the conformal cross ratios satisfy |u| 2\\Delta_\\phi\\ + 2n for each integer n as l -> infinity. We show how the rate of approach is controlled by the twist and OPE coefficient of the leading twist operator in the \\phi\\ x \\phi\\ OPE, and we discuss SCFTs and the 3d Ising Model as examples. Additionally, we show that the OPE coefficients of other large spin operators appearing in the OPE are bounded as l -> infinity. We interpret these results as a statement about superhorizon locality in AdS for general CFTs.
Thermodynamics of charged Lovelock: AdS black holes
International Nuclear Information System (INIS)
We investigate the thermodynamic behavior of maximally symmetric charged, asymptotically AdS black hole solutions of Lovelock gravity. We explore the thermodynamic stability of such solutions by the ordinary method of calculating the specific heat of the black holes and investigating its divergences which signal second-order phase transitions between black hole states. We then utilize the methods of thermodynamic geometry of black hole spacetimes in order to explain the origin of these points of divergence. We calculate the curvature scalar corresponding to a Legendre-invariant thermodynamic metric of these spacetimes and find that the divergences in the black hole specific heat correspond to singularities in the thermodynamic phase space. We also calculate the area spectrum for large black holes in the model by applying the Bohr-Sommerfeld quantization to the adiabatic invariant calculated for the spacetime. (orig.)
An investigation of AdS2 backreaction and holography
Engelsöy, Julius; Mertens, Thomas G.; Verlinde, Herman
2016-07-01
We investigate a dilaton gravity model in AdS2 proposed by Almheiri and Polchinski [1] and develop a 1d effective description in terms of a dynamical boundary time with a Schwarzian derivative action. We show that the effective model is equivalent to a 1d version of Liouville theory, and investigate its dynamics and symmetries via a standard canonical framework. We include the coupling to arbitrary conformal matter and analyze the effective action in the presence of possible sources. We compute commutators of local operators at large time separation, and match the result with the time shift due to a gravitational shockwave interaction. We study a black hole evaporation process and comment on the role of entropy in this model.
On Information Loss in AdS$_3$/CFT$_2$
Fitzpatrick, A Liam; Li, Daliang; Wang, Junpu
2016-01-01
We discuss information loss from black hole physics in AdS$_3$, focusing on two sharp signatures infecting CFT$_2$ correlators at large central charge $c$: 'forbidden singularities' arising from Euclidean-time periodicity due to the effective Hawking temperature, and late-time exponential decay in the Lorentzian region. We study an infinite class of examples where forbidden singularities can be resolved by non-perturbative effects at finite $c$, and we show that the resolution has certain universal features that also apply in the general case. Analytically continuing to the Lorentzian regime, we find that the non-perturbative effects that resolve forbidden singularities qualitatively change the behavior of correlators at times $t \\sim S_{BH}$, the black hole entropy. This may resolve the exponential decay of correlators at late times in black hole backgrounds. By Borel resumming the $1/c$ expansion of exact examples, we explicitly identify 'information-restoring' effects from heavy states that should correspo...
Correlation Functions of Winding Strings in AdS_3
Minces, Pablo
2008-01-01
We review certain results for amplitudes of spectral flowed operators in string theory on AdS_3. We present the modified Knizhnik-Zamolodchikov and null vector equations to be satisfied by correlators including w=1 operators. We then discuss the three point function of two w=1 and one w=0 operators in the x-basis, and perform a consistency check on the definition of the w=1 operator. We finally exhibit the steps in the calculation of the winding conserving four point functions for operators in arbitrary spectral flowed sectors, both in the m- and x-basis, under the only assumption that at least one of the operators is in the spectral flowed image of the highest weight discrete representation.
Energy Technology Data Exchange (ETDEWEB)
Bretzke, Wolf-Ruediger [Barkawi Management Consultants GmbH und Co. KG, Muenchen (Germany)
2010-09-15
The authors examine the question of whether and to what extent globalization changes in the future. For this purpose, an expert survey is carried out. The results of this expert surveys are described in the contribution under consideration: (1) The vast majority of climate scientists says that limiting global warming to two degrees celsius only is possible if the developed industrial countries reduce their emissions by 80 % compared to the year 1990; (2) This inevitably requires interventions of the policy for sustainable management; (3) Despite the economic and financial crisis the policy shall not ease its ambitious targets in the medium term; (4) The threat of global warming is a global problem. The solution of this problem at political level requires a more advanced form of 'global governance'; (5) A significant increase in the petroleum price may affect the globally distributed industrial 'settlement structures' and the configuration of logistics networks. A possible adaptation may consist in multistage distribution systems with regional, customer-oriented stocks; (6) A stronger focus of companies to a low-polluting, sustainable business can be facilitated and supported by financial incentives; (7) It is not expected that professional buyers of companies do not sacrifice price advantages in low-wage countries; (8) Scale effects in the production by special factories result in a continuation of the current 'production footprints' even if this model significantly increases the transport intensity of the economy due to the longer distance between the place of production and the place of consumption; (9) In the logistics presumable there exists any other single measure to eliminate many pollutants such as the replacement of air cargo by sea freight; (10) Economic-historically, globalization has developed very quickly. The experts disagree on whether globalization slows down or whether the globalization changes at a constant speed.
International Programmes on ADS: The Asian ADS Network
International Nuclear Information System (INIS)
As the management of radioactive wastes is a common issue for all the countries utilizing nuclear energy and also for those intending to start it, international multilateral collaboration must be of great importance for effective research and development of transmutation technology for long lived nuclides. Collaboration in Asian region, however, had been less active in comparison to European countries, though nuclear power generation would increase significantly in Asia. Considering this context, the former Japan Atomic Energy Research Institute (JAERI) convened the ‘International Symposium on Accelerator driven Transmutation Systems and Asia ADS Network Initiative’ on March 24 and 25, 2003 at Tokyo, Japan in cooperation with Kyoto University, Osaka University, High Energy Accelerator Research Organization and Tokyo Institute of Technology. Through the discussion in the symposium, common understanding was developed in Japanese, Korean and Chinese scientists concerning the importance of establishing an international network among Asian countries to facilitate information exchange for R&D of ADS. Based on this understanding, five workshops were held so far. The workshop covers the national R&D programmes on ADS including subcritical reactor physics, cross-section measurements, high energy particle physics, accelerator technology, material technology and MA fuel technology. From the fifth workshop, information exchange for R&D on innovative fast reactors for nuclear transmutation was also included
Islands of stability and recurrence times in AdS
Green, Stephen R; Lehner, Luis; Liebling, Steven L
2015-01-01
We study the stability of anti-de Sitter (AdS) spacetime to spherically symmetric perturbations of a real scalar field in general relativity. Further, we work within the context of the "two time framework" (TTF) approximation, which describes the leading nonlinear effects for small amplitude perturbations, and is therefore suitable for studying the weakly turbulent instability of AdS---including both collapsing and non-collapsing solutions. We have previously identified a class of quasi-periodic (QP) solutions to the TTF equations, and in this work we analyze their stability. We show that there exist several families of QP solutions that are stable to linear order, and we argue that these solutions represent islands of stability in TTF. We extract the eigenmodes of small oscillations about QP solutions, and we use them to predict approximate recurrence times for generic non-collapsing initial data in the full (non-TTF) system. Alternatively, when sufficient energy is driven to high-frequency modes, as occurs ...
Islands of stability and recurrence times in AdS
Green, Stephen R.; Maillard, Antoine; Lehner, Luis; Liebling, Steven L.
2015-10-01
We study the stability of anti-de Sitter (AdS) spacetime to spherically symmetric perturbations of a real scalar field in general relativity. Further, we work within the context of the "two time framework" (TTF) approximation, which describes the leading nonlinear effects for small amplitude perturbations, and is therefore suitable for studying the weakly turbulent instability of AdS—including both collapsing and noncollapsing solutions. We have previously identified a class of quasiperiodic (QP) solutions to the TTF equations, and in this paper we analyze their stability. We show that there exist several families of QP solutions that are stable to linear order, and we argue that these solutions represent islands of stability in TTF. We extract the eigenmodes of small oscillations about QP solutions, and we use them to predict approximate recurrence times for generic noncollapsing initial data in the full (non-TTF) system. Alternatively, when sufficient energy is driven to high-frequency modes, as occurs for initial data far from a QP solution, the TTF description breaks down as an approximation to the full system. Depending on the higher order dynamics of the full system, this often signals an imminent collapse to a black hole.
Discrete capacity choice problems in repeated and scaled investment
Luo, Cheng
2016-01-01
Most previous studies on real options are confined to the realm of continuous modelling while more practical discrete models are restricted by the methodology of solutions. This thesis applies the discount factor methodology to solve two scaling capacity choice problems: one is the scaling capacity expansions without switching options raised from Dxit and Pindyck (1994) and the other one is the case adding switching opportunities raised from Pindyck (1988). We respectively establish two discr...
International Nuclear Information System (INIS)
Assuming that very often a long transport route from the factory of the manufacturer to the provided site has to be reckoned with, in general only transport with a ship is possible. As each site is only called by a certain steamship line, at a very early stage of planning the nuclear power plant the possibilities and capacities of the lines and means of transportation under discussion should be investigated. In planning the unloading equipment at the site, due consideration should be given to the fact that at a later time this equipment should also be suitable for the transport of heavy components and spent fuel assemblies. (orig.)
Rethinking Information Theory for Mobile Ad Hoc Networks
Andrews, Jeff; Haenggi, Martin; Berry, Randy; Jafar, Syed; Guo, Dongning; Shakkottai, Sanjay; Heath, Robert; Neely, Michael; Weber, Steven; Yener, Aylin
2007-01-01
The subject of this paper is the long-standing open problem of developing a general capacity theory for wireless networks, particularly a theory capable of describing the fundamental performance limits of mobile ad hoc networks (MANETs). A MANET is a peer-to-peer network with no pre-existing infrastructure. MANETs are the most general wireless networks, with single-hop, relay, interference, mesh, and star networks comprising special cases. The lack of a MANET capacity theory has stunted the development and commercialization of many types of wireless networks, including emergency, military, sensor, and community mesh networks. Information theory, which has been vital for links and centralized networks, has not been successfully applied to decentralized wireless networks. Even if this was accomplished, for such a theory to truly characterize the limits of deployed MANETs it must overcome three key roadblocks. First, most current capacity results rely on the allowance of unbounded delay and reliability. Second, ...
Energy Technology Data Exchange (ETDEWEB)
Fitzpatrick, A.Liam; /Boston U.; Kaplan, Jared; /SLAC
2012-02-14
We show that suitably regulated multi-trace primary states in large N CFTs behave like 'in' and 'out' scattering states in the flat-space limit of AdS. Their transition matrix elements approach the exact scattering amplitudes for the bulk theory, providing a natural CFT definition of the flat space S-Matrix. We study corrections resulting from the AdS curvature and particle propagation far from the center of AdS, and show that AdS simply provides an IR regulator that disappears in the flat space limit.
Facilities Management and Added Value
DEFF Research Database (Denmark)
Jensen, Per Anker
2010-01-01
is based on literature reviews of the most influential journals within the academic fields of FM, Corporate Real Estate Management and Business to Business Marketing and discussions between participants of the research group working on a further exploration and testing of the FM Value Map. Conclusions......Aim: This paper aims to present different models of the concept of the added value of Facilities Management (FM), including the FM Value Map, which forms the basis of research group in EuroFM, and to present some of the results of this research collaboration. Approach and methodology: The paper...... on the aimed output) and the internal resource based view (with a focus on the input from FM and RE). Good relationship management and building on trust shows to be equally important as delivering the agreed services. In order to measure the multi-dimensional components of adding value both qualitative...
MUSICAL ARRANGEMENT OF MEDIA ADS
Chernyshov Alexander V.
2015-01-01
The music-compositional principles of commercial and political advertising and also the self-promotion of electronic media (radio, television, Internet) are considered in this mediatext: from the elementary beeps, symbolic functions, emblems/logos and musical brands to the sound engineering technology to underscore the product's name and the complex synthesis between music and intra movements and color-light design of frames. Simultaneously examines, how the musical arrangement of ethereal ad...
Functional foods for added value
Mark-Herbert, Cecilia
2002-01-01
In this study innovation involves the development of a new product category; i.e. new products, new processes and new business. The development process is conveyed in narratives where a radically new product group, functional foods, is developed. These high-tech food products are associated with added value for the food business as well as for individuals and society at large. In the past decades Swedish food companies have faced an increasing competition. With increased competitive pressures...
Grothmann, T.; Grecksch, K.; Winges, M.; Siebenhüner, B.
2013-03-01
Several case studies show that "soft social factors" (e.g. institutions, perceptions, social capital) strongly affect social capacities to adapt to climate change. Many soft social factors can probably be changed faster than "hard social factors" (e.g. economic and technological development) and are therefore particularly important for building social capacities. However, there are almost no methodologies for the systematic assessment of soft social factors. Gupta et al. (2010) have developed the Adaptive Capacity Wheel (ACW) for assessing the adaptive capacity of institutions. The ACW differentiates 22 criteria to assess six dimensions: variety, learning capacity, room for autonomous change, leadership, availability of resources, fair governance. To include important psychological factors we extended the ACW by two dimensions: "adaptation motivation" refers to actors' motivation to realise, support and/or promote adaptation to climate. "Adaptation belief" refers to actors' perceptions of realisability and effectiveness of adaptation measures. We applied the extended ACW to assess adaptive capacities of four sectors - water management, flood/coastal protection, civil protection and regional planning - in North Western Germany. The assessments of adaptation motivation and belief provided a clear added value. The results also revealed some methodological problems in applying the ACW (e.g. overlap of dimensions), for which we propose methodological solutions.
Grothmann, T.; Grecksch, K.; Winges, M.; Siebenhüner, B.
2013-12-01
Several case studies show that social factors like institutions, perceptions and social capital strongly affect social capacities to adapt to climate change. Together with economic and technological development they are important for building social capacities. However, there are almost no methodologies for the systematic assessment of social factors. After reviewing existing methodologies we identify the Adaptive Capacity Wheel (ACW) by Gupta et al. (2010), developed for assessing the adaptive capacity of institutions, as the most comprehensive and operationalised framework to assess social factors. The ACW differentiates 22 criteria to assess 6 dimensions: variety, learning capacity, room for autonomous change, leadership, availability of resources, fair governance. To include important psychological factors we extended the ACW by two dimensions: "adaptation motivation" refers to actors' motivation to realise, support and/or promote adaptation to climate; "adaptation belief" refers to actors' perceptions of realisability and effectiveness of adaptation measures. We applied the extended ACW to assess adaptive capacities of four sectors - water management, flood/coastal protection, civil protection and regional planning - in northwestern Germany. The assessments of adaptation motivation and belief provided a clear added value. The results also revealed some methodological problems in applying the ACW (e.g. overlap of dimensions), for which we propose methodological solutions.
International Programmes on ADS: ISTC
International Nuclear Information System (INIS)
The International Science and Technology Center (ISTC) is an intergovernmental organization, created to serve the goal of improving global safety and security. The European Union, Japan, the Russian Federation and the United States of America, on the basis of a multinational agreement, established ISTC in 1992. The ISTC focused its efforts on funding research projects related to key safety and security technologies including advanced nuclear technology. Since the first ISTC funded project in 1994, Accelerator Driven Systems, Transmutation research and a holistic approach to the nuclear fuel cycle were the areas where ISTC made a real impact on international development in these fields. Given the international dimension of the problem, the research communities of the ISTC member states quickly realized that ISTC projects offered a very flexible and fruitful cooperation platform to address many difficult issues of the nuclear fuel cycle. Highly competent expert communities of ISTC member states benefited from a well defined and transparent mode of operation of ISTC and objective oriented project funding strategy. The ISTC projects related to transmutation of radioactive waste and ADS can be classified in the following thematic areas: - ADS concepts; - Accelerator development; - Spallation target studies; - Nuclear data and spallation process studies; - Minor actinides studies related to ADS; - Partitioning and extraction
Absorptive Capacity and Diversity
DEFF Research Database (Denmark)
Kristinsson, Kári
One of the most influential contributions to neo-Schumpeterian economics is Cohen and Levinthal‘s papers on absorptive capacity. Since their publication in the late 1980s and early 1990s the concept absorptive capacity has had substantial impact on research in economics and management, including...... international business, organizational economics, strategic management, technology management and last but not least neo-Schumpeterian economics. The goal of this dissertation is to examine what many consider as neglected arguments from the work by Cohen and Levinthal and thereby illuminate an otherwise...... overlooked area of research. Although research based on Cohen and Levinthal‘s work has made considerable impact, there is scarcity of research on certain fundamental points argued by Cohen and Levinthal. Among these is the importance of employee diversity as well as the type and nature of interaction between...
Functional Capacity Evaluation & Disability
Chen, Joseph J.
2007-01-01
Function, Impairment, and Disability are words in which many physicians have little interest. Most physicians are trained to deal with structure and physiology and not function and disability. The purpose of this article is to address some of the common questions that many physicians have with the use of functional capacity evaluation and disability and also to provide a unifying model that can explain the medical and societal variables in predicting disability. We will first define the funct...
Baltazar, João; Lamas, José; Vale, Nuno; Bandeira, Rui; Duarte, Pedro
2008-01-01
Bivalve culture is an important economic activity in several regions and it should be carefully managed towards its sustainability. In this context, carrying capacity (CC) evaluation of coastal ecosystems for bivalve culture became an important topic. Mathematical modelling is a common approach for CC estimation. The objective of this work is to evaluate the importance of spatial resolution of mathematical models for CC evaluation. Obtained results suggest that low resolution mode...
Firefighters' physical work capacity
Lindberg, Ann-Sofie
2014-01-01
The overall aim of this thesis was to identify valid, simple, and inexpensive physical tests that can be used for evaluation of firefighters’ physical work capacity. Paper I included fulltime- and part-time firefighters (n = 193), aged 20-60 years. Perceived physical demands of firefighting work tasks were ranked, and comparisons between subject groups rating were done with the Mann Whitney U-test and Binominal test. Papers II and III included male firefighters and civilian men and women (n =...
Assimilative Capacity Revisited
Cairns, John
2008-01-01
Assimilative capacity is the ability of natural systems to assimilate humankind's wastes. Wastes (output) of some species in natural systems are the resources (input) of other species. Before the Industrial Revolution, this concept of input and output held true for human activity, but industrialization created wastes that were qualitatively and quantitatively different from those of natural systems. The unique nature of some persistent wastes that accumulate in organisms over long periods of ...
Deficiency of employability capacity
Pelse I.; Vilka L.
2012-01-01
Young unemployed people have comprised one of the significantly largest groups of the unemployed people in Latvia in recent years. One of the reasons why young people have difficulty integrating into the labour market is the “expectation gap” that exists in the relations between employers and the new generation of workers. Employers focus on capacity-building for employability such individual factors as strength, patience, self-discipline, self-reliance, self-motivation, etc., which having a ...
Nilsson, C. S.; Andrews, J. C.; Scully-Power, P.; Ball, S.; Speechley, G.; Latham, A. R. (Principal Investigator)
1980-01-01
The Tasman Front was delineated by airborne expendable bathythermograph survey; and an Heat Capacity Mapping Mission (HCMM) IR image on the same day shows the same principal features as determined from ground-truth. It is clear that digital enhancement of HCMM images is necessary to map ocean surface temperatures and when done, the Tasman Front and other oceanographic features can be mapped by this method, even through considerable scattered cloud cover.
International Nuclear Information System (INIS)
Since the start of this year, the Dutch energy company Nuon has been using a computer system to formulate real-time responses to national capacity imbalances in the electricity supply market. The work earns Nuon a fixed fee from TenneT (Dutch Transmission System Operator) and ensures a more stable imbalance price for everyone. The key to success has been the decision to start the project from scratch
International Nuclear Information System (INIS)
We present a comprehensive analysis of the AdS/Ricci-flat correspondence, a map between a class of asymptotically locally AdS spacetimes and a class of Ricci-flat spacetimes. We provide a detailed derivation of the map, discuss a number of extensions and apply it to a number of important examples, such as AdS on a torus, AdS black branes and fluids/gravity metrics. In particular, the correspondence links the hydrodynamic regime of asymptotically flat black p-branes or the Rindler fluid with that of AdS. It implies that this class of Ricci-flat spacetimes inherits from AdS a generalized conformal symmetry and has a holographic structure. We initiate the discussion of holography by analyzing how the map acts on boundary conditions and holographic 2-point functions
Caldarelli, M M; Goutéraux, B; Skenderis, K
2014-01-01
We present a comprehensive analysis of the AdS/Ricci-flat correspondence, a map between a class of asymptotically locally AdS spacetimes and a class of Ricci-flat spacetimes. We provide a detailed derivation of the map, discuss a number of extensions and apply the map to a number of important examples, such as AdS on a torus, AdS black branes and fluids/gravity metrics. In particular, the map links the hydrodynamic regime of asymptotically flat black $p$-branes or the Rindler fluid with that of AdS. The map implies that this class of Ricci-flat spacetimes inherits from AdS a generalized conformal symmetry and has a holographic structure. We initiate the discussion of holography by analyzing how the map acts on boundary conditions and holographic 2-point functions.
Magnetic Mass in 4D AdS Gravity
Araneda, Rene; Miskovic, Olivera; Olea, Rodrigo
2016-01-01
We provide a fully-covariant expression for the diffeomorphic charge in 4D anti-de Sitter gravity, when the Gauss-Bonnet and Pontryagin terms are added to the action. The couplings of these topological invariants are such that the Weyl tensor and its dual appear in the on-shell variation of the action, and such that the action is stationary for asymptotic (anti) self-dual solutions in the Weyl tensor. In analogy with Euclidean electromagnetism, whenever the self-duality condition is global, both the action and the total charge are identically vanishing. Therefore, for such configurations the magnetic mass equals the Ashtekhar-Magnon-Das definition.
Magnetic mass in 4D AdS gravity
Araneda, René; Aros, Rodrigo; Miskovic, Olivera; Olea, Rodrigo
2016-04-01
We provide a fully covariant expression for the diffeomorphic charge in four-dimensional anti-de Sitter gravity, when the Gauss-Bonnet and Pontryagin terms are added to the action. The couplings of these topological invariants are such that the Weyl tensor and its dual appear in the on-shell variation of the action and such that the action is stationary for asymptotic (anti-)self-dual solutions in the Weyl tensor. In analogy with Euclidean electromagnetism, whenever the self-duality condition is global, both the action and the total charge are identically vanishing. Therefore, for such configurations, the magnetic mass equals the Ashtekhar-Magnon-Das definition.
Canonical energy and hairy AdS black holes
Hyun, Seungjoon; Park, Sang-A.; Yi, Sang-Heon
2016-08-01
We propose the modified version of the canonical energy which was introduced originally by Hollands and Wald. Our construction depends only on the Euler-Lagrange expression of the system and thus is independent of the ambiguity in the Lagrangian. After some comments on our construction, we briefly mention on the relevance of our construction to the boundary information metric in the context of the AdS/CFT correspondence. We also study the stability of three-dimensional hairy extremal black holes by using our construction.
Routing Protocol of Sparse Urban Vehicular Ad Hoc Networks
Li, Huxiong
Vehicular ad hoc network (VANET) is an application of mobile ad hoc technology in transportation systems, it has become an important part of ITS. Since multi-hop link is hard to set up in sparse VANET, a traffic-aware routing (TAR) protocol is proposed which estimates vehicle average neighbors (VAN) of roads by exchanging beacon messages between encounter vehicles. Road with high VAN is preferred to be selected as part of forwarding path at intersection. Packets are forwarded to the next intersection in road in a greedy manner. Simulations show that TAR outperforms the compared protocols in terms of both packet delivery ratio and average end-to-end delay.
Capacity Utilization and Market Power
Fagnart, J.F.; Licandro, O.; Sneessens, Henri
1997-01-01
In a monopolistic competition framework, we propose a dynamic model in which capacity underutilization is a macroeconomic equilibrium feature relying on a diversity of microeconomic situations. Capacity underutilization follows from microeconomic uncertainty at the time firms must decide on their productive capacity. We settle a relationship between capacity utilization and markups via the effect of capacity utilization rate changes on firms' market power. We show that such a relationship inf...
Competence building capacity shortage
International Nuclear Information System (INIS)
The objective of the project 'Competence Building Capacity Shortage' has been 'to increase knowledge about central approaches aimed at solving the peaking capacity problem in restructured power systems'. With respect to reserve markets, a model was developed in the project to analyze the relations between reserve requirements and prices in the spot and reserve markets respectively. A mathematical model was also developed and implemented, which also includes the balance market, and has a good ability to predict the relations between these markets under various assumptions. With some further development, this model can be used fore realistic analyses of these markets in a Nordic context. It was also concluded that certain system requirements with respect to frequency and time deviation can be relaxed without adverse effects. However, the requirements to system bias, Frequency Activated Operating Reserves and Frequency Activated Contingency Reserves cannot be relaxed, the latter because they must cover the dimensioning fault in the system. On the other hand, Fast Contingency Reserves can be reduced by removing requirements to national balances. Costs can furthermore be reduced by increasingly adapting a Nordic as opposed to national approach. A model for stepwise power flow was developed in the project, which is especially useful to analyze slow power system dynamics. This is relevant when analysing the effects of reserve requirements. A model for the analysis of the capacity balance in Norway and Sweden was also developed. This model is useful for looking at the future balance under various assumptions regarding e.g. weather conditions, demand growth and the development of the generation system. With respect to the present situation, if there is some price flexibility on the demand side and system operators are able to use reserves from the demand side, the probability for load shedding during the peak load hour is close to zero under the weather conditions after
Durability of organobentonite-amended liner for decelerating chloroform transport.
He, Shichong; Zhu, Lizhong
2016-04-01
Chloroform is added to landfill for suppressing methane generation, which however may transport through landfill liners and lead to contamination of groundwater. To decelerate chloroform transport, the enhanced sorption ability of clay liners following organobentonite addition was tested. In this study, we used batch sorption to evaluate sorption capacity of chloroform to organobentonite, followed by column tests and model simulations for assessing durability of different liners. Results show that adding 10% CTMAB-bentonite (organobentonite synthesized using cetyltrimethylammonium bromide) increased the duration of a bentonite liner by 88.5%. CTMAB-bentonite consistently showed the highest sorption capacity (Qm) among six typical organobentonites under various environmental conditions. The removal rate of chloroform by CTMAB-bentonite was 3.6-23 times higher than that by natural soils. According to the results derived by model simulation, a 70-cm 10% CTMAB-bentonite liner exhibited much better durability than a 100-cm compact clay liner (CCL) and natural bentonite liner evidenced by the delayed and lower peak of eluent concentration. A minimum thickness of 65.8 cm of the 10% CTMAB-bentonite liner could completely sorb the chloroform in a 100-m-high landfill. The 10% CTMAB-bentonite liner exhibiting much better durability has the promise for reducing environmental risk of chloroform in landfill. PMID:26874063
Li, Wei; Pähtz, Thomas; He, Zhiguo; Cao, Zhixian
2016-01-01
Volumetric sediment concentrations computed by phase-resolving swash morphodynamic models are shown to exceed unity minus porosity (i.e. the maximal physically possible concentration value) by up to factor of $10^5$ when using standard expressions to compute the sediment transport rate. An ad hoc limit of sediment concentration is introduced as a means to evaluate consequences of exceeding physically realistic concentration by standard expressions. We find that implementation of this ad hoc limit strongly changes the quantitative and qualitative predictions of phase-resolving swash morphodynamic models, suggesting that existing swash predictions are unreliable. This is because standard expressions inappropriately consider or ignore the fact that the shallow swash water depth limits the storage capacity of transported sediment.
Stability of Charged Global AdS$_4$ Spacetimes
Arias, Raúl; Serantes, Alexandre
2016-01-01
We study linear and nonlinear stability of asymptotically AdS$_4$ solutions in Einstein-Maxwell-scalar theory. After summarizing the set of static solutions we first examine thermodynamical stability in the grand canonical ensemble and the phase transitions that occur among them. In the second part of the paper we focus on nonlinear stability in the microcanonical ensemble by evolving radial perturbations numerically. We find hints of an instability corner for vanishingly small perturbations of the same kind as the ones present in the uncharged case. Collapses are avoided, instead, if the charge and mass of the perturbations come to close the line of solitons. Finally we examine the soliton solutions. The linear spectrum of normal modes is not resonant and instability turns on at extrema of the mass curve. Linear stability extends to nonlinear stability up to some threshold for the amplitude of the perturbation. Beyond that, the soliton is destroyed and collapses to a hairy black hole. The relative width of t...
Spectrum and statistical entropy of AdS black holes
International Nuclear Information System (INIS)
Popular approaches to quantum gravity describe black hole microstates differently and apply different statistics to count them. Since the relationship between the approaches is not clear, this obscures the role of statistics in calculating the black hole entropy. We address this issue by discussing the entropy of eternal AdS black holes in dimension four and above within the context of a midisuperspace model. We determine the black hole eigenstates and find that they describe the quantization in half integer units of a certain function of the Arnowitt-Deser-Misner (ADM) mass and the cosmological constant. In the limit of a vanishing cosmological constant (the Schwarzschild limit) the quantized function becomes the horizon area and in the limit of a large cosmological constant it approaches the ADM mass of the black holes. We show that in the Schwarzschild limit the area quatization leads to the Bekenstein-Hawking entropy if Boltzmann statistics are employed. In the limit of a large cosmological constant the Bekenstein-Hawking entropy can be recovered only via Bose statistics. The two limits are separated by a first order phase transition, which seems to suggest a shift from ''particlelike'' degrees of freedom at large cosmological constant to geometric degrees of freedom as the cosmological constant approaches zero.
Thermal transport in fractal systems
DEFF Research Database (Denmark)
Kjems, Jørgen
1992-01-01
Recent experiments on the thermal transport in systems with partial fractal geometry, silica aerogels, are reviewed. The individual contributions from phonons, fractons and particle modes, respectively, have been identified and can be described by quantitative models consistent with heat capacity...
International Programmes on ADS: IAEA
International Nuclear Information System (INIS)
The IAEA recognizes that there are four major challenges facing the long term development of nuclear energy as a part of the world’s energy mix: improvement of the economic competitiveness, meeting increasingly stringent safety requirements, adhering to the criteria of sustainable development, and public acceptance. Meeting the sustainability criteria is the driving force behind IAEA’s activity in the area of innovative transmutation reactor technology development and, in particular, Accelerator Driven Systems. The framework for all the IAEA activities in the ADS area is the Technical Working Group on Fast Reactors (TWG-FR). In response to strong common R&D needs in the Member States, the TWG-FR acts as a catalyst for international information exchange and collaborative R&D. It provides a forum for exchange of non-commercial scientific and technical information, and a forum for international cooperation on generic research and development programmes on advances in fast reactors and fast spectrum accelerator driven systems. Its present members are the following 15 IAEA Member States: Belarus, Brazil, China, France, Germany, India, Italy, Japan, Kazakhstan, Republic of Korea, Russian Federation, Sweden, Switzerland, United Kingdom, and United States of America, as well as 3 international organizations: ISTC, OECD-NEA, and EU (EC). As observers, the TWG-FR has welcomed Argentina and Belgium. Last but not least, the IAEA is providing the ADS Research and Development Database. It contains information about ADS related R&D programmes, existing and planned experimental facilities as well as programmes, methods and data development efforts, design studies, and so forth
ADS activities in the Netherlands
International Nuclear Information System (INIS)
The problem of long-lived nuclear waste was under consideration in the Netherlands during a number of years. Within this framework different reactor concepts have been considered. One of the most promising concepts appears to be the Accelerator Driven System (ADS) or Fast Energy Amplifier (FEA), as it has been proposed by C. Rubbia of CERN. To unite the effort on accelerator driven reactor concepts in the Netherlands, KEMA, NIKHEF, ECN, KVI, and IRI have joined their forces in a co-operative program since 1996. Cupertino covers the technical fields of nuclear data, reactor physics, and innovative fuels. (author)
Heterogeneous LTE-Advanced Network Expansion for 1000x Capacity
DEFF Research Database (Denmark)
Hu, Liang; Sanchez, Maria Laura Luque; Maternia, Michal;
2013-01-01
this paper studies LTE (Long-Term Evolution)-Advanced heterogeneous network expansion in a dense urban environment for a 1000 times capacity increase and a 10 times increase in minimum user data rate requirements. The radio network capacity enhancement via outdoor and indoor small cell densificat......this paper studies LTE (Long-Term Evolution)-Advanced heterogeneous network expansion in a dense urban environment for a 1000 times capacity increase and a 10 times increase in minimum user data rate requirements. The radio network capacity enhancement via outdoor and indoor small cell....... In terms of spectrum requirements we have increased the total amount of downlink spectrum to a total of 300 MHz by re-farming spectrum and adding new spectrum in 3.5 GHz band. We conclude that new spectrum at 3.5 GHz is essential to reach the set target network capacity....
International Nuclear Information System (INIS)
The readout of a classical memory can be modelled as a problem of quantum channel discrimination, where a decoder retrieves information by distinguishing the different quantum channels encoded in each cell of the memory (Pirandola 2011 Phys. Rev. Lett. 106 090504). In the case of optical memories, such as CDs and DVDs, this discrimination involves lossy bosonic channels and can be remarkably boosted by the use of nonclassical light (quantum reading). Here we generalize these concepts by extending the model of memory from single-cell to multi-cell encoding. In general, information is stored in a block of cells by using a channel-codeword, i.e. a sequence of channels chosen according to a classical code. Correspondingly, the readout of data is realized by a process of ‘parallel’ channel discrimination, where the entire block of cells is probed simultaneously and decoded via an optimal collective measurement. In the limit of a large block we define the quantum reading capacity of the memory, quantifying the maximum number of readable bits per cell. This notion of capacity is nontrivial when we suitably constrain the physical resources of the decoder. For optical memories (encoding bosonic channels), such a constraint is energetic and corresponds to fixing the mean total number of photons per cell. In this case, we are able to prove a separation between the quantum reading capacity and the maximum information rate achievable by classical transmitters, i.e. arbitrary classical mixtures of coherent states. In fact, we can easily construct nonclassical transmitters that are able to outperform any classical transmitter, thus showing that the advantages of quantum reading persist in the optimal multi-cell scenario. (paper)
Surface retention capacity calculation
David, Vaclav; Dostal, Tomas
2010-05-01
Flood wave transformation in the floodplain is the phenomenon which is researched within interdisciplinary project NIVA - Water Retention in Floodplains and Possibilities of Retention Capacity Increase. The project focuses on broad range of floodplain ecosystem services and mitigation of flooding is one of them. Despite main influence on flood wave transformation is due to flow retardation, retention in surface depressions within floodplain has been analyzed to get better overview of whole transformation process. Detail digital relief model (DRM) has been used for given purposes to be able to analyze terrain depressions volumes. The model was developed with use of stereophotogrammetric evaluation of airborne images with high resolution of 10 cm. It was essential for purposes of presented analysis not to apply pit removal routines which are often used for generation of DRM for hydrological modelling purposes. First, the methodology of analysis was prepared and tested on artificial surface. This surface was created using random raster generation, filtration and resampling with final resolution of 1000 x 1000 units and height of maximum 10 units above datum. The methodology itself is based on analysis of areas inundated by water at different elevation levels. Volume is than calculated for each depression using extraction of terrain elevations under corresponding water level. The method was then applied on the area of Lužnice River floodplain section to assess retention capacity of real floodplain. The floodplain had to be cut into sections perpendicular to main river orientation for analyses as the method was tested for square shaped area without any significant inclination. Results obtained by mentioned analysis are presented in this paper. Acknowledgement Presented research was accomplished within national project NIVA - Water Retention in Floodplains and Possibilities of Retention Capacity Increase, nr. QH82078. The project is funded by Ministry of Agriculture of
Capacities of Grassmann channels
Bradler, Kamil; Jauregui, Rocio
2010-01-01
A new class of quantum channels called Grassmann channels is introduced and their classical and quantum capacity is calculated. The channel class appears in a study of the two-mode squeezing operator constructed from operators satisfying the fermionic algebra. We compare Grassmann channels with the channels induced by the bosonic two-mode squeezing operator. Among other results, we challenge the relevance of calculating entanglement measures to assess or compare the ability of bosonic and fermionic states to send quantum information to uniformly accelerated frames.
DEFF Research Database (Denmark)
Landex, Alex
2011-01-01
zone(s) the possible conflicts with other trains (also in the opposite direction) are taken into account leading to more trustworthy results. Although the UIC 406 methodology proposes that the railway network should be divided into line sections when trains turn around and when the train order is...... changed, this paper recommends that the railway lines are not always be divided. In case trains turn around on open (single track) line, the capacity consumption may be too low if a railway line is divided. The same can be the case if only few trains are overtaken at an overtaking station. For dead end...
Savulescu, Julian; Kahane, Guy
2011-01-01
Enhancing Human Capacities is the first to review the very latest scientific developments in human enhancement. It is unique in its examination of the ethical and policy implications of these technologies from a broad range of perspectives. Presents a rich range of perspectives on enhancement from world leading ethicists and scientists from Europe and North America The most comprehensive volume yet on the science and ethics of human enhancement Unique in providing a detailed overview of current and expected scientific advances in this area Discusses both general conceptual and ethical issues
Improved Method for Determining the Heat Capacity of Metals
Barth, Roger; Moran, Michael J.
2014-01-01
An improved procedure for laboratory determination of the heat capacities of metals is described. The temperature of cold water is continuously recorded with a computer-interfaced temperature probe and the room temperature metal is added. The method is more accurate and faster than previous methods. It allows students to get accurate measurements…
Legal capacity of the elderly in Greece.
Giannouli, Vaitsa; Tsolaki, Magda
2014-01-01
Legal capacity of the elderly people in Greece is of great legal, medical and social importance, but has received little attention till now from medical literature. This paper aims to study whether elderly people with dementia are able to participate in legal contracts like sales, purchases, loans, leases, donations and testaments. We tried to introduce a new test for the above legal-financial contracts and show some preliminary findings. The test consists of six examined relevant domains concerning basic monetary skills, cash transactions, bank statement management, financial conceptual knowledge, knowledge of potential heirs (beneficiaries) and assets/estate and finally the decision making process for different dilemmas on sales, purchases, loans, leases, donations and testaments. We studied 203 people. Eighty three people were healthy, 64 with Alzheimer's disease (AD) (10 with severe AD, 22 with moderate, and 32 with mild AD), 10 with Parkinson's disease (PD), and 46 with amnestic Mild Cognitive Impairment (aMCI). Individuals were included in the study only if they were aged 60 and over and only if they had a partner or a guardian who could give information on the individual's daily living. The exclusion criteria were predefined as follows: history of any other mental health disease and/or any other serious somatic health disease except for their official diagnosis of dementia. Results showed statistically significant differences with all three groups of patients characterized as incapable for legal-financial actions. Patients with severe AD (P<0.001), patients with moderate AD (P<0.001), patients with mild AD (P<0.001), patients with PD (P<0.001) and aMCI patients (P<0.001) differed significantly from healthy controls. Further research should include more extensive sampling of elderly patients with varying demographic characteristics in Greece, to confirm and expand our initial findings. In conclusion, our new test which is based on Marson's theoretical model
Entanglement Entropy of AdS Black Holes
Directory of Open Access Journals (Sweden)
Maurizio Melis
2010-11-01
Full Text Available We review recent progress in understanding the entanglement entropy of gravitational configurations for anti-de Sitter gravity in two and three spacetime dimensions using the AdS/CFT correspondence. We derive simple expressions for the entanglement entropy of two- and three-dimensional black holes. In both cases, the leading term of the entanglement entropy in the large black hole mass expansion reproduces exactly the Bekenstein-Hawking entropy, whereas the subleading term behaves logarithmically. In particular, for the BTZ black hole the leading term of the entanglement entropy can be obtained from the large temperature expansion of the partition function of a broad class of 2D CFTs on the torus.
Minimal area submanifolds in AdS x compact
Graham, C Robin
2014-01-01
We describe the asymptotic behavior of minimal area submanifolds in product spacetimes of an asymptotically hyperbolic space times a compact internal manifold. In particular, we find that unlike the case of a minimal area submanifold just in an asymptotically hyperbolic space, the internal part of the boundary submanifold is constrained to be itself a minimal area submanifold. For applications to holography, this tells us what are the allowed "flavor branes" that can be added to a holographic field theory. We also give a compact geometric expression for the spectrum of operator dimensions associated with the slipping modes of the submanifold in the internal space. We illustrate our results with several examples, including some that haven't appeared in the literature before.
A Survey of Multicast Routing Protocols for Vehicular Ad Hoc Networks
Waqar Farooq; Khan, Muazzam A.; Saad Rehman; Nazar Abbas Saqib
2015-01-01
Vehicular Ad Hoc Networks (VANETs) are autonomous and self-configurable wireless ad hoc networks and considered as a subset of Mobile Ad Hoc Networks (MANETs). MANET is composed of self-organizing mobile nodes which communicate through a wireless link without any network infrastructure. A VANET uses vehicles as mobile nodes for creating a network within a range of 100 to 1000 meters. VANET is developed for improving road safety and for providing the latest services of intelligent transport sy...
Airport Capacity Forecast : Short-term forecasting of runway capacity
Hesselink, Henk; Nibourg, Joyce; D'Estampes, Ludovic; Lezaud, Pascal
2014-01-01
International audience Airports expect major benefits from increasing predictability of the operation. This paper will investigate the use of forecast information to determine forecast airport capacity, which will allow airport stakeholders to optimize the use of their resources. The focus will be on forecasting runway capacity, at most airports the major factor for the overall airport capacity. The possibility to model forecast runway capacity, based on probabilistic inputs, will be inves...
Strategic network design of Java Island fuel supply with production-transportation solution
Dianawati, Fauzia; Farizal, -; Surjandari, Isti; Marzuli, Rully
2011-10-01
This study aims to find more efficient supply network, from refineries / imports to fuel terminal, which still uses the Tanker, Tank Trucks or Rail Tank Wagon with an alternative pipeline that are considered more efficient than other transport modes, as well as gaining pipeline transportation network optimization analysis tailored to the capabilities/ capacity of refinery production and capacity of the pipe mode. With the complexity of the number of 3 point sources of supply, 19 destination of terminal, 4 kinds of products and 4 types of transport modes, transport-production model modified by adding multi-modal transport and investment costs of new pipeline. Then coded in Lingo program which adopts Branch & Bound technique and input the processed data in order to obtain an optimal distribution pattern produced the lowest distribution costs. This B&B solution was also compared with SCO solution which is a metaheuristic method. The results of this study lead to the development of new modes of pipeline connections in amount of 4 alternatives, generated from the optimal solution, but still potentially earned savings of about IDR 1 Trillion per year from cost-efficiency of product procurement and transportation costs.
Deficiency of employability capacity
Directory of Open Access Journals (Sweden)
Pelse I.
2012-10-01
Full Text Available Young unemployed people have comprised one of the significantly largest groups of the unemployed people in Latvia in recent years. One of the reasons why young people have difficulty integrating into the labour market is the “expectation gap” that exists in the relations between employers and the new generation of workers. Employers focus on capacity-building for employability such individual factors as strength, patience, self-discipline, self-reliance, self-motivation, etc., which having a nature of habit and are developed in a long-term work socialization process, which begins even before the formal education and will continue throughout the life cycle. However, when the socialization is lost, these habits are depreciated faster than they can be restored. Currently a new generation is entering the labour market, which is missing the succession of work socialization. Factors, such as rising unemployment and poverty in the background over the past twenty years in Latvia have created a very unfavourable employability background of “personal circumstances” and “external factors”, which seriously have impaired formation of the skills and attitudes in a real work environment. The study reveals another paradox – the paradox of poverty. Common sense would want to argue that poverty can be overcome by the job. However, the real state of affairs shows that unfavourable coincidence of the individual, personal circumstances and external factors leads to deficit of employability capacity and possibility of marked social and employment deprivation.
Capacity Building in Land Management
DEFF Research Database (Denmark)
Enemark, Stig; Ahene, Rexford
2003-01-01
There is a significant need for capacity building in the interdisciplinary area of land management especially in developing countries and countries in transition, to deal with the complex issues of building efficient land information systems and sustainable institutional infrastructures. Capacity...
Impacts of technology on the capacity needs of the US national airspace system
Ausrotas, Raymond A.; Simpson, Robert W.
1992-01-01
A review of the U.S. air transportation system is undertaken, focusing on airspace and airport capacity. Causes of delay and congestion are investigated. Aircraft noise is identified as the fundamental hindrance to capacity improvement. Research areas for NASA are suggested to improve capacity through technology.
Evaluation model for safety capacity of chemical industrial park based on acceptable regional risk
Institute of Scientific and Technical Information of China (English)
Guohua Chen; Shukun Wang; Xiaoqun Tan
2015-01-01
The paper defines the Safety Capacity of Chemical Industrial Park (SCCIP) from the perspective of acceptable regional risk. For the purpose of exploring the evaluation model for the SCCIP, a method based on quantitative risk assessment was adopted for evaluating transport risk and to confirm reasonable safety transport capacity of chemical industrial park, and then by combining with the safety storage capacity, a SCCIP evaluation model was put forward. The SCCIP was decided by the smaller one between the largest safety storage capacity and the maximum safety transport capacity, or else, the regional risk of the park will exceed the acceptable level. The developed method was applied to a chemical industrial park in Guangdong province to obtain the maximum safety transport capacity and the SCCIP. The results can be realized in the regional risk control of the park effectively.
Capacity Building in Land Administration
DEFF Research Database (Denmark)
Enemark, Stig; Williamson, I
2004-01-01
Capacity building increasingly seen as a key component of land administration projects in developing and countries in transition undertaken by the international development banks and individual country development assistance agencies. However, the capacity building concept is often used within a...... should be dealt with as capacity building projects in themselves. The article introduces a conceptual analytical framework that provides some guidance when dealing with capacity building for land administration in support of a broader land policy agenda....
Capacities on a finite lattice
Machida, Motoya
2011-01-01
In his influential work Choquet systematically studied capacities on Boolean algebras in a topological space, and gave a probabilistic interpretation for completely monotone (and completely alternating) capacities. Beyond complete monotonicity we can view a capacity as a marginal condition for probability distribution over the distributive lattice of dual order ideals. In this paper we discuss a combinatorial approach when capacities are defined over a finite lattice, and investigate Fr\\'{e}c...
International Nuclear Information System (INIS)
We use the AdS/CFT correspondence to compute the conductivity of massive N = 2 hypermultiplet fields at finite baryon number density in an N = 4 SU(Nc) super-Yang-Mills theory plasma in the large Nc, large 't Hooft coupling limit. The finite baryon density provides charge carriers analogous to electrons in a metal. An external electric field then induces a finite current which we determine directly. Our result for the conductivity is good for all values of the mass, external field and density, modulo statements about the yet-incomplete phase diagram. In the appropriate limits it agrees with known results obtained from analyzing small fluctuations around equilibrium. For large mass, where we expect a good quasi-particle description, we compute the drag force on the charge carriers and find that the answer is unchanged from the zero density case. Our method easily generalizes to a wide class of systems of probe branes in various backgrounds
DEFF Research Database (Denmark)
Schröder, Philipp J.H.; Sørensen, Allan
2010-01-01
Real-world industries are composed from heterogeneous firms and substantial intra-industry reallocations take place, i.e. high productivity firms squeeze out low productivity firms. Previous tax-tool comparisons have not included these central forces of industry structure. This paper examines a...... general equilibrium monopolistic competition model with heterogeneous firms and intra-industry reallocations. We show that the welfare superiority of ad valorem over unit taxes under imperfect competition is not only preserved but amplified. The additional difference between the tools arises because unit...... taxes distort relative prices, which in turn reduces average industry productivity through reallocations (the survival and increased market share of lower productivity firms). Importantly, numerical solutions of the model reveal that the relative welfare loss from using the unit tax increases...
MUSICAL ARRANGEMENT OF MEDIA ADS
Directory of Open Access Journals (Sweden)
Chernyshov Alexander V.
2015-01-01
Full Text Available The music-compositional principles of commercial and political advertising and also the self-promotion of electronic media (radio, television, Internet are considered in this mediatext: from the elementary beeps, symbolic functions, emblems/logos and musical brands to the sound engineering technology to underscore the product's name and the complex synthesis between music and intra movements and color-light design of frames. Simultaneously examines, how the musical arrangement of ethereal advertising is involved in creation the emotional drama or bravado which reach the level of explicit or associative counterpoint 'music with the advertised object or subject' and which extend to expression of cultural image of all the broadcast channel. The article explores the works of the next genres like infomercial, teleshopping, film-ad, and autonomous commercials that have been produced in European countries or USA.
Landfill Construction and Capacity Expansion
Andre, F.J.; Cerda, E.
2003-01-01
We study the optimal capacity and lifetime of landfills taking into account their sequential nature.Such an optimal capacity is characterized by the so-called Optimal Capacity Condition.Particular versions of this condition are obtained for two alternative settings: first, if all the landfills are t
Competitive Capacity Investment under Uncertainty
X. Li (Xishu); R.A. Zuidwijk (Rob); M.B.M. de Koster (René); R. Dekker (Rommert)
2016-01-01
textabstractWe consider a long-term capacity investment problem in a competitive market under demand uncertainty. Two firms move sequentially in the competition and a firm’s capacity decision interacts with the other firm’s current and future capacity. Throughout the investment race, a firm can eith
Thermodynamic and classical instability of AdS black holes in fourth-order gravity
International Nuclear Information System (INIS)
We study thermodynamic and classical instability of AdS black holes in fourth-order gravity. These include the BTZ black hole in new massive gravity, Schwarzschild-AdS black hole, and higher-dimensional AdS black holes in fourth-order gravity. All thermodynamic quantities which are computed using the Abbot-Deser-Tekin method are used to study thermodynamic instability of AdS black holes. On the other hand, we investigate the s-mode Gregory-Laflamme instability of the massive graviton propagating around the AdS black holes. We establish the connection between the thermodynamic instability and the GL instability of AdS black holes in fourth-order gravity. This shows that the Gubser-Mitra conjecture holds for AdS black holes found from fourth-order gravity
Conde Sala, Josep Lluís; Reñé Ramírez, Ramon; Turró Garriga, Oriol; Gascón-Bayarri, J.; Juncadella i Puig, Montserrat; Moreno-Cordón, L.; Viñas Diez, V.; Vilalta Franch, Joan; Garre Olmo, Josep
2013-01-01
Abstract Background: Several studies have identified certain caregiver factors that can produce variability in their assessments of the capacities of patients with Alzheimer"s disease (AD). Objectives: To identify the caregiver variables associated with variability in their ratings of patients" capacities. Methods: Consecutive sample of 221 out-patients with AD and their family caregivers. The capacities evaluated by caregivers were: the degree of functional disability, using the Disability A...
Which AdS3 configurations contribute to the SCFT2 elliptic genus?
Murthy, S.V.; Nawata, S.
2011-01-01
According to the AdS=CFT duality, the superconformal index of a superconformal eld theory should have an AdS interpretation as a Euclidean functional integral with periodic boundary conditions on the fermions. Unlike the thermal case, the Euclidean continuation of the supersymmetric AdS black hole d
Hybrid algorithm for project scheduling with capacity constraint
Institute of Scientific and Technical Information of China (English)
Cheng Xu; Wu Cheng
2008-01-01
Motivated by the projects constrained by space capacity and resource transporting time,a project scheduling problem with capacity constraint was modeled.A hybrid algorithm is proposed,which uses the ideas of bi-level scheduling and project decomposition technology,and the genetic algorithm and tabu search is combined.Topological reordering technology is used to improve the efficiency of evaluation.Simulation results show the proposed algorithm can obtain satisfied scheduling results in acceptable time.
Vehicular Ad Hoc Network Mobility Model
Directory of Open Access Journals (Sweden)
Budi Rahmadya
2014-01-01
Full Text Available Indonesia is one of developing countries with high land traffic density. This traffic density could cause traffic jam, traffic accidents and other disturbances. This research had developed a simulator that could calculate the traffic density of roads in urban areas. With the use of this simulator, the researcher could calculate the time needed if the source node transports the message to the destination node by using the ad hoc network communication facility. In this research, every vehicle utilizes multi-hop communication in a communication network. The vehicle sends the message through flooding message and passes on the received message to other vehicles. Based on the simulation done on map size 10 km x 10 km with a total of 20 vehicles on the road, it was calculated that the simulator could transmit the message to its destination on the 106th second from node 3 and with the total of 200 vehicles on the road, the simulator could transmit the message to its destination on the 22nd second from node 5.
Capacity Credit and Security of Supply
DEFF Research Database (Denmark)
Chozas, Julia Fernandez; Mathiesen, Brian Vad
2015-01-01
on hourly 2013 data from offshore wind, onshore wind, wave and solar PV power production. The analysis is done over a year based on hourly values and based on a historical year. Provided that the capacity credit is the amount of power variable renewables can reliably be expected to produce at the times when...... demand for electricity is highest, the study focuses on the capacity credit of future Danish scenarios including high penetrations of offshore wind, onshore wind, wave and solar PV. The results of this project can ultimately lead towards the improvement of existing rules and methods in system planning...... and the development of integrated energy systems where the electricity, heating and transport sectors are merged....
Privatization of contact-handled transuranic waste transportation services
International Nuclear Information System (INIS)
The U.S. Department of Energy (DOE) currently stores and generates contact-handled (CH) transuranic (TRU) waste at 10 major and 13 smaller sites across the United States. The opening of the Waste Isolation Pilot Plant (WIPP) in May 1998 will begin the use of a radioactive waste transportation system to transport TRU waste from these sites to the WIPP for disposal. The DOE will transport CH-TRU waste in a U.S. Nuclear Regulatory Commission (NRC)-certified type B package called the TRUPACT-II. The Carlsbad Area Office (CAO) has determined that the CH-TRU waste transportation system is sufficiently well defined to allow privatization, resulting in significant cost savings. The CAO manages the National Transuranic Program and has developed the National Transuranic (TRU) Waste Management Plan for integrating TRU waste management activities throughout the DOE complex. The management plan outlines an aggressive schedule for transporting and disposing of TRU waste at the WIPP. The WIPP is scheduled to begin receiving CH-TRU waste in May 1998, at which time five truck sets (a truck set consists of tractor, trailer, and three TRUPACT-IIs) will be in service. Starting in 1998, truck sets will be added until the fleet size reaches 20 in 2000. The WIPP CH-TRU waste-handling capacity will start at a rate of 250 shipments per year in 1998 and will increase to 850 shipments per year by the year 2000
What factors influence mitigative capacity?
International Nuclear Information System (INIS)
This article builds on Yohe's seminal piece on mitigative capacity, which elaborates 'determinants' of mitigative capacity, also reflected in the IPCC's third assessment report. We propose a revised definition, where mitigative capacity is a country's ability to reduce anthropogenic greenhouse gas emissions or enhance natural sinks. By 'ability' we mean skills, competencies, fitness, and proficiencies that a country has attained which can contribute to GHG emissions mitigation. A conceptual framework is proposed, linking mitigative capacity to a country's sustainable development path, and grouping the factors influencing mitigative capacity into three main sets: economic factors, institutional ones, and technology. Both quantitative and qualitative analysis of factors is presented, showing how these factors vary across countries. We suggest that it is the interplay between the three economic factors-income, abatement cost and opportunity cost-that shape mitigative capacity. We find that income is an important economic factor influencing mitigative capacity, while abatement cost is important in turning mitigative capacity into actual mitigation. Technology is a critical mitigative capacity, including the ability to absorb existing climate-friendly technologies or to develop innovative ones. Institutional factors that promote mitigative capacity include the effectiveness of government regulation, clear market rules, a skilled work force and public awareness. We briefly investigate such as high abatement cost or lack of political willingness that prevent mitigative capacity from being translated into mitigation
Penedones, Joao
2016-01-01
We introduce the AdS/CFT correspondence as a natural extension of QFT in a fixed AdS background. We start by reviewing some general concepts of CFT, including the embedding space formalism. We then consider QFT in a fixed AdS background and show that one can define boundary operators that enjoy very similar properties as in a CFT, except for the lack of a stress tensor. Including a dynamical metric in AdS generates a boundary stress tensor and completes the CFT axioms. We also discuss some applications of the bulk geometric intuition to strongly coupled QFT. Finally, we end with a review of the main properties of Mellin amplitudes for CFT correlation functions and their uses in the context of AdS/CFT.
Recurring Anomaly Detection System (ReADS)
National Aeronautics and Space Administration — Overview: ReADS can analyze text reports, such as aviation reports and problem or maintenance records. ReADS uses text clustering algorithms to group loosely...
Capacity Utilization in European Railways
DEFF Research Database (Denmark)
Khadem Sameni, Melody; Landex, Alex
2013-01-01
At the strategic level, railways currently use different indices to estimate how ‘value’ is generated by using railway capacity. However, railway capacity is a multidisciplinary area, and attempts to develop various indices cannot provide a holistic measure of operational efficiency. European...... railways are facing a capacity challenge which is caused by passenger and freight demand exceeding the track capacity supply. In the absence of a comprehensive railway capacity manual, methodologies are needed to assess how well railways use their track capacity. This paper presents a novel and...... unprecedented approach for this aim. Relative operational efficiency of 24 European railways in capacity utilization is studied for the first time by data envelopment analysis (DEA). It deviates from previous applications of DEA in the railway industry that are conducted to analyze cost efficiency of railways...
Implementing Smart Antenna System in Mobile Ad Hoc Networks
Directory of Open Access Journals (Sweden)
Supriya Kulkarni P
2014-06-01
Full Text Available As the necessity of exchanging and sharing data increases, users demand easy connectivity, and fast networks whether they are at work, at home, or on the move. Nowadays, users are interested in interconnecting all their personal electronic devices (PEDs in an ad hoc fashion on the move. This type of network is referred to as Mobile Ad hoc NETwork (MANET. When in such network a smart antenna System (SAS is implemented then we can achieve maximum capacity and improve the quality and coverage. So we are intended to implement such a SAS in the MANET. In this paper we have shown significance of Throughput and Bit Error Rate by implementing SAS in MANET using MATLABR2010a.
Canadian hydrocarbon transportation system : transportation assessment
International Nuclear Information System (INIS)
This document provided an assessment of the Canadian hydrocarbon transportation system. In addition to regulating the construction and operation of Canada's 45,000 km of pipeline that cross international and provincial borders, Canada's National Energy Board (NEB) regulates the trade of natural gas, oil and natural gas liquids. The ability of pipelines to delivery this energy is critical to the country's economic prosperity. The pipeline system includes large-diameter, cross-country, high-pressure natural gas pipelines, low-pressure crude oil and oil products pipelines and small-diameter pipelines. In order to assess the hydrocarbon transportation system, staff at the NEB collected data from pipeline companies and a range of publicly available sources. The Board also held discussions with members of the investment community regarding capital markets and emerging issues. The assessment focused largely on evaluating whether Canadians benefit from an efficient energy infrastructure and markets. The safety and environmental integrity of the pipeline system was also evaluated. The current adequacy of pipeline capacity was assessed based on price differentials compared with firm service tolls for major transportation paths; capacity utilization on pipelines; and, the degree of apportionment on major oil pipelines. The NEB concluded that the Canadian hydrocarbon transportation system is working effectively, with an adequate capacity in place on existing natural gas pipelines, but with a tight capacity on oil pipelines. It was noted that shippers continue to indicate that they are reasonably satisfied with the services provided by pipeline companies and that the NEB-regulated pipeline companies are financially stable. 14 refs, 11 tabs., 28 figs., 4 appendices
Accounting Relations in Bilateral Value Added Trade
Robert Stehrer
2013-01-01
Abstract The increasing international fragmentation of production has triggered the development of a number of widely used indicators accounting for value added ﬂows in the world economy. This paper generalises these measures by simultaneously considering the import side and focusing on bilateral gross and value added trade ﬂows. It discusses how these indicators relate to each other, the role of double counting in bilateral value added trade, and aggregation issues in global value added ﬂows...
Drug transporters in breast cancer
DEFF Research Database (Denmark)
Kümler, Iben; Stenvang, Jan; Moreira, José;
2015-01-01
basis. Although effective, their usefulness is limited by the inevitable development of resistance, a lack of response to drug-induced cancer cell death. A large body of research has resulted in the characterization of a plethora of mechanisms involved in resistance; ATP-binding cassette transporter...... proteins, through their function in xenobiotic clearance, play an important role in resistance. We review here the current evidence for drug transporters as biomarkers and the benefit of adding drug transporter modulators to conventional chemotherapy....
Amendments to the Law on Value Added Tax in Kosovo
Directory of Open Access Journals (Sweden)
Simeana Beshi
2016-03-01
Full Text Available Main purpose of this paper is to explore and analyze the objectives and effects of amendments in the Law on Value Added Tax (VAT as part of the new fiscal package in Kosovo. This paper is based on a quantitative analysis. Some of the methods used in this paperwork are: historical- , descriptive-, and comparative method. It relies on facts and researches conducted by international organizations, based on productive forces and on the development of economic capacities in general, also a comparative overview of the fiscal policies applied in different states. This paper presents also the challenges of Kosovo, towards EU, by harmonizing tax legislation, fiscal policy and combating tax evasion.
Directory of Open Access Journals (Sweden)
Manasvi Kalra,
2016-02-01
Full Text Available The apps consist of advertisements to promote their products. Not all of them are appropriate to resume. Therefore various algorithms have been used in order to block those apps from existence but none of them is completely successful. In our app we are using an antivirus which can by default block those spy apps and remove them from the web page. The algorithm which has been used makes use of various ant viruses in the background which detect irrelevant and intimate apps and then our algorithm will demolish them. Certain apps are non-trustworthy where one click can spy all the mobile data. They block those apps and works on security. We are working on secure ads for mobile apps. It can also work as a basic antivirus where it detects the viruses like malwares in any of your installed apps or downloads. It will create a popup of discarding or keeping it. Mobile applications can be downloaded from anywhere like amazon, googleplay, apps store etc. There is no rigorous verification of an application when it is uploaded to the market. One can easily develop a malicious application and upload it to the app market. The user itself is responsible for accepting the risk of an app available from secondary markets. Therefore, we have decided to develop this app to make the market more secure and bounded. In future, It will take the mobile market while consuming minimal additional resources and preserving user privacy.
Symmetry Breaking, Central Charges and the AdS_2/CFT_1 Correspondence
Cadoni, Mariano; Mignemi, Salvatore
2000-01-01
When two-dimensional Anti-de Sitter space (AdS_2) is endowed with a non-constant dilaton the origin of the central charge in the Virasoro algebra generating the asymptotic symmetries of AdS_2 can be traced back to the breaking of the SL(2,R) isometry group of AdS_2. We use this fact to clarify some controversial results appeared in the literature about the value of the central charge in these models.
Bidirectional ROF Links with Dynamic Capacity Allocation
Directory of Open Access Journals (Sweden)
Rakesh Kumar Chandan , Dharmendra Singh
2013-10-01
Full Text Available : Radio over fiber (ROF technology is an integration of wireless and fiber optic network. It plays vital role for broad band wireless communication. The well known advantages of optical as a transmission medium such as low loss, light weight, large bandwidth characteristics, small size and low cable cost make it the ideal and most flexible solution for efficiently transporting radio signals to remotely located antenna site in a wireless network. The joint venture of radio signal and optical fiber technology provides dynamic capacity allocation in radio over fiber links.
High capacity optical links for datacentre connectivity
DEFF Research Database (Denmark)
Tafur Monroy, Idelfonso; Usuga, Mario; Vegas Olmos, Juan José
There is a timely and growing demand for high capacity optical data transport solutions to provide connectivity inside data centres and between data centres located at different geographical locations. The requirements for reach are in the order of 2 km for intra-datacentre and up to 100 km for...... inter-datacentre connectivity. Moreover, the requirements for such connectivity solutions include also low cost, high data rate and desirable features such as energy efficiency and reduced interfacing cost. In this paper we review several approaches for intra and inter datacentre that use advanced...
Environmental Baseline File National Transportation
International Nuclear Information System (INIS)
This Environmental Baseline File summarizes and consolidates information related to the national-level transportation of commercial spent nuclear fuel. Topics addressed include: shipments of commercial spent nuclear fuel based on mostly truck and mostly rail shipping scenarios; transportation routing for commercial spent nuclear fuel sites and DOE sites; radionuclide inventories for various shipping container capacities; transportation routing; populations along transportation routes; urbanized area population densities; the impacts of historical, reasonably foreseeable, and general transportation; state-level food transfer factors; Federal Guidance Report No. 11 and 12 radionuclide dose conversion factors; and national average atmospheric conditions
Potentially beneficial spill-related effects of chemicals routinely added to crude oils
International Nuclear Information System (INIS)
Amoco Trinidad Oil Company produces 60,000 bbl/d of oil from the Trinidadian offshore. The oil is pipelined ashore where it is processed and returned offshore to a buoy mooring for transport up Trinidad's east coast. Amoco Trinidad has developed comprehensive oil spill contingency plans, starting from computer models of spill scenarios. The models used initially assumed that the oils would emulsify quickly and the spills would become highly viscous and persistent, reaching the shoreline in 15-24 h. Such behavior would render ineffective the use of dispersants as a spill countermeasure. Studies showed a poor potential capability of physical recovery systems for spills off the Trinidad east coast due to high sea states, strong winds, and other factors. These results led to questioning of the spill model's assumptions, and laboratory tests were conducted to study the actual behavior of the crude oils. It was found that the oil was difficult to emulsify and highly prone to breakup and dispersion. These surprising results were explained by the presence of surfactants added during processing. A revised modelling exercise showed that if the surfactants stay with the oil, spills up to 100,000 bbl will dissipate in 15 h or less at average wind conditions. To guard against the possibility that the surfactants may not stay with the spilled oil, and to help accelerate dispersion of oil spills, Amoco Trinidad has developed a dispersant-use capacity for its spill contingency plan. It is suggested that additives normally added to crude oils during production and processing in other areas may also be providing spill cleanup benefits similar to those found in the Trinidad case. 9 refs., 1 fig., 4 tabs
Bed capacity and surgical waiting lists: a simulation analysis
Directory of Open Access Journals (Sweden)
Manel Antelo
2015-12-01
Full Text Available Waiting time for elective surgery is a key problem in the current medical world. This paper aims to reproduce, by a Monte Carlo simulation model, the relationship between hospital capacity, inpatient activity, and surgery waiting list size in teaching hospitals. Inpatient activity is simulated by fitting a Normal distribution to real inpatient activity data, and the effect of the number of beds on inpatient activity is modelled with a linear regression model. Analysis is performed with data of the University Multi-Hospital Complex of Santiago de Compostela (Santiago de Compostela, Spain, by considering two scenarios regarding the elastiticity of demand with bed increase. If demand does not grow with an increase on bed capacity, small changes lead to drastic reductions in the waiting lists. However, if demand grows as bed capacity does, adding additional capacity merely makes waiting lists worse.
Reactivity monitoring in ADS systems
International Nuclear Information System (INIS)
Monitoring reactivity in an ADS should be performed on-line with a simple, accurate and robust technique. Within the range of experimental reactor techniques, no single technique can be selected which meet these requirements. Therefore a combination of different techniques has to be chosen in a way that various off-line techniques serve as a calibration for the on-line measurement technique. As an on-line measurement technique, the current/flux reactivity indicator is the most simple and robust solution. It is based on the fact that in a subcritical multiplying medium with a driving source the flux level is proportional to the driving source intensity, hence the beam current, and the reactivity level. However, since the proportionality constant depends on a number of core dependent parameters and detector characteristics, this current-to-flux indicator has to be calibrated on a regular basis. For this calibration, one could benefit from the occurrence of accelerator beam trips to determine the reactivity level in dollars by means of a prompt jump analysis of the flux level change. Hence, the prompt jump reactivity indicator could act as a first calibration tool of the current-to-flux indicator. Since the prompt jump indicator still relies on the value for the effective delayed neutron fraction to determine reactivity level, complementary techniques have to be used to obtain a more accurate determination of the reactivity. Techniques based on reactor noise methods such as RAPJA technique which is combination of the Rossi-alpha method and Prompt jump analysis can be used in this respect. In the future the bi-spectral ratio from the Cf - source driven noise analysis could be used for this purpose. (author)
Historical Literature in the ADS
Eichhorn, G.; Kurtz, M. J.; Accomazzi, A.; Grant, C. S.
1997-12-01
The Astrophysics Data System at http://adswww.harvard.edu is in the process of scanning the historical astronomical literature and making it available through the World Wide Web. We have scanned several volumes from the early 1800's of the "Astronomische Nachrichten", and the "Monthly Notices of the Royal Astronomical Society", the two oldest astronomical journals. We also have several of the early volumes of the "Astrophysical Journal" and the "Astronomical Journal" available. For all the journals that we cover, we have scanned volume 1. These early volumes can be accessed on a page-by-page basis. We plan to continue to scan this historical literature and complete these journals within the next year. We are also collaborating with a preservation project at Harvard University. This project will microfilm selected parts of astronomical Observatory reports. We plan to scan these microfilms to produce electronic images of these reports and put them on-line in the ADS. We hope to eventually cover most of the astronomical literature. In order to organize the scanned pages into articles, we need tables of contents (ToC). The early issues of the journals did not have printed ToC pages, so this needs to be done by hand. We do not have the financial resources to build these ToCs. We are looking for collaborators who would be willing to work with us in building these ToCs for the older journals and observatory reports. If you are interested in such a project, please contact the first author at gei@cfa.harvard.edu.
Directory of Open Access Journals (Sweden)
Dušanić Slobodan S.
2004-01-01
Full Text Available Both Roman generals and modern historians have tended to find Julian's moves in the civil war of AD 361 hazardous as well as difficult to understand. This is especially true of his long, ultra-rapid and semi-clandestine journey down the Danube, which was carried out by a dangerously small corps (under the command of the Usurper himself ! and ended with a very brief visit to Sirmium. A competent and, otherwise, cautious general, Julian must have had strong reasons for the risky haste that led him to Sirmium. These reasons were not primarily of a military nature, though enlistment of fresh troops and formation of vexillationes was among the measures he undertook/ initiated in the Pannonian metropolis. A (neglected passage (13. 287 a of his Letter to the Athenians (? mainly written during the river journey but sent from Sirmium itself implies that his visit to Sirmium was chiefly caused by his urgent need to secure the rich mines of precious metals managed by that city (mines situated in the Drinus valley and the Mt. Cer area, as well as silver and gold objects (coins, ingots, plates etc. stored in Sirmium, which had a mint and the metal officinae of its own. All this would help him i.a. distribute the donativa, already promised to his soldiers and officers. Analogous strategies, inspired by the old experience that the pecunia and/or metalla is/are nervus belli civilis, left traces in the sources describing the wars between Constantine I and Licinius, Vitellius and Vespasian, Otho and Vitellius — to cite the most illustrative examples only.
Light-cone AdS/CFT-adapted approach to AdS fields/currents, shadows, and conformal fields
Metsaev, R R
2015-01-01
Light-cone gauge formulation of fields in AdS space and conformal field theory in flat space adapted for the study of AdS/CFT correspondence is developed. Arbitrary spin mixed-symmetry fields in AdS space and arbitrary spin mixed-symmetry currents, shadows, and conformal fields in flat space are considered on an equal footing. For the massless and massive fields in AdS and the conformal fields in flat space, simple light-cone gauge actions leading to decoupled equations of motion are found. For the currents and shadows, simple expressions for all 2-point functions are also found. We demonstrate that representation of conformal algebra generators on space of currents, shadows, and conformal fields can be built in terms of spin operators entering the light-cone gauge formulation of AdS fields. This considerably simplifies the study of AdS/CFT correspondence. Light-cone gauge actions for totally symmetric arbitrary spin long conformal fields in flat space are presented. We apply our approach to the study of tota...
Available transmission capacity assessment
Directory of Open Access Journals (Sweden)
Škokljev Ivan
2012-01-01
Full Text Available Effective power system operation requires the analysis of vast amounts of information. Power market activities expose power transmission networks to high-level power transactions that threaten normal, secure operation of the power system. When there are service requests for a specific sink/source pair in a transmission system, the transmission system operator (TSO must allocate the available transfer capacity (ATC. It is common that ATC has a single numerical value. Additionally, the ATC must be calculated for the base case configuration of the system, while generation dispatch and topology remain unchanged during the calculation. Posting ATC on the internet should benefit prospective users by aiding them in formulating their requests. However, a single numerical value of ATC offers little for prospect for analysis, planning, what-if combinations, etc. A symbolic approach to the power flow problem (DC power flow and ATC offers a numerical computation at the very end, whilst the calculation beforehand is performed by using symbols for the general topology of the electrical network. Qualitative analysis of the ATC using only qualitative values, such as increase, decrease or no change, offers some new insights into ATC evaluation, multiple transactions evaluation, value of counter-flows and their impact etc. Symbolic analysis in this paper is performed after the execution of the linear, symbolic DC power flow. As control variables, the mathematical model comprises linear security constraints, ATC, PTDFs and transactions. The aim is to perform an ATC sensitivity study on a five nodes/seven lines transmission network, used for zonal market activities tests. A relatively complicated environment with twenty possible bilateral transactions is observed.
Institute of Scientific and Technical Information of China (English)
王玲玲; 姚文艺; 王文龙; 杨二; 陈丽; 张攀
2015-01-01
Soil erosion and sediment transport in Losses Plateau region are crucial for sustainable development of the local region and downstream of Yellow river due to the harmful sedimentation in the plain area. This study was to investigate the sediment transport capacity and flow-sediment relationship in different topographical units of different scales in loess region to explore the countermeasures for solving the sediment-related environmental issues. The Peijiamao watershed in losses region was selected as prototype for observation, including the embedded whole slope runoff plot (0.25 hm2) and 3 hydrological stations that were first branch of Qiaogou (subwatershed of Qiaogou watershed), Qiaogou watershed (subwatershed of Peijiamao watershed), and Peijiamao watershed (3930 hm2) with increasing scales, acting as 4 different topographical units. The rainfall, runoff and sediment contents data at these sites were recorded and collected from 1986 to 2008. Results showed that during the observation period the runoff depth and the sediment transport modulus at the annual timescales of the slope scale were more than that of the watershed scale, probably due to the well-known gravitational erosion occurring on the steeper slopes at slope scale in this region. When the spatial scale was up to the watershed scale, at the annual timescale the runoff depth increased with the spatial scale, but the sediment transport modulus decreased with spatial scale. However, at the inter-event timescale the maximum value of the runoff depth and the sediment transport modulus may occur at the different topographical units influenced by the rainfall process, rainfall duration, rainfall spatial distribution, the antecedent soil moisture content and other factors. Totally, 67.74% of the runoff peaks occurred at whole slope runoff plot and 29.03% at entire Peijiamao watershed. However, 38.71% of sediment transport modulus occurred at whole slope runoff plot and 48.39% occurred at entire Peijiamao
Institutional capacity and climate actions
International Nuclear Information System (INIS)
This paper explores the concept and substance of country-level institutional capacity in the context of future climate-related actions. The main thrust of the paper is that an institutional approach, based on capacity assessments, could provide useful insights, both at national and international levels, on the appropriate next steps for climate actions. Thus, the paper proposes a generic assessment of institutional capacity, with the aim to help develop a common understanding across countries of what institutional capacity actually is and what institutional capacity would be required for various forms of future actions. However, the paper fully acknowledges that country-level institutional capacity assessments are essentially country-specific and need to be undertaken in a national context. Some national case studies have been prepared together with this paper to emphasise the country-specific aspect of this debate. To be sure, current capacities are not the only factor in deciding on future policy options. First, governments need not have all the capacity in place before taking steps to combat climate change. It may well be that, within the next decades, countries will be able to increase their capacity, either through their own means or with assistance from the international community. Second, to some degree, and in some instances, the adoption of a commitment - either domestic or international - may act as a driver for capacity building. This was the case for some industrialized and transitioning countries, whose commitments in Kyoto have provided an impetus for the development of the capacity needed to implement and adhere to them. Finally, institutional capacity needs are only one key consideration when assessing future climate policy options. Other considerations when evaluating different forms of future actions include environmental effectiveness, cost-effectiveness, the need to deal with economic and scientific uncertainties, and other domestic policy
A rigorous proof of MIMO channel capacity's increase with antenna number
Institute of Scientific and Technical Information of China (English)
GONG Jian-min; M.R. Soleymani; J.F.Hayes
2008-01-01
It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity, in the multiple-input multiple-output(MIMO) communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.
Competitive Capacity Investment under Uncertainty
Li, Xishu; Zuidwijk, Rob; Koster, René; Dekker, Rommert
2016-01-01
textabstractWe consider a long-term capacity investment problem in a competitive market under demand uncertainty. Two firms move sequentially in the competition and a firm’s capacity decision interacts with the other firm’s current and future capacity. Throughout the investment race, a firm can either choose to plan its investments proactively, taking into account possible responses from the other firm, or decide to respond reactively to the competition. In both cases, the optimal decision at...
Protein domain organisation: adding order
Directory of Open Access Journals (Sweden)
Kummerfeld Sarah K
2009-01-01
Full Text Available Abstract Background Domains are the building blocks of proteins. During evolution, they have been duplicated, fused and recombined, to produce proteins with novel structures and functions. Structural and genome-scale studies have shown that pairs or groups of domains observed together in a protein are almost always found in only one N to C terminal order and are the result of a single recombination event that has been propagated by duplication of the multi-domain unit. Previous studies of domain organisation have used graph theory to represent the co-occurrence of domains within proteins. We build on this approach by adding directionality to the graphs and connecting nodes based on their relative order in the protein. Most of the time, the linear order of domains is conserved. However, using the directed graph representation we have identified non-linear features of domain organization that are over-represented in genomes. Recognising these patterns and unravelling how they have arisen may allow us to understand the functional relationships between domains and understand how the protein repertoire has evolved. Results We identify groups of domains that are not linearly conserved, but instead have been shuffled during evolution so that they occur in multiple different orders. We consider 192 genomes across all three kingdoms of life and use domain and protein annotation to understand their functional significance. To identify these features and assess their statistical significance, we represent the linear order of domains in proteins as a directed graph and apply graph theoretical methods. We describe two higher-order patterns of domain organisation: clusters and bi-directionally associated domain pairs and explore their functional importance and phylogenetic conservation. Conclusion Taking into account the order of domains, we have derived a novel picture of global protein organization. We found that all genomes have a higher than expected
The progress of researches on ADS in China
International Nuclear Information System (INIS)
The conceptual study of Accelerator Driven System (ADS) had lasted for about five years and ended in 1999 in China. As one project of 'the major state basic research program (973)' in energy domain, which is sponsored by the China Ministry of Science and Technology (MOST), a five years program of basic research for ADS physics and related technology has been launched since 2000. CIAE (China Institute of Atomic Energy), IHEP (Institute of High Energy Physics), PKU-IHIP (Institute of Heavy Ion Physics in Peking University) and other institutions are jointly carrying on the research. The research activities are focused on HPPA physics and technology, reactor physics of external source driven sub-critical assembly, nuclear data base and material study. For HPPA, a high current injector consisting of an ECR ion source, LEBT and a RFQ accelerating structure of 3MeV will be built. In reactor physics study, a series of neutron multiplication experimental study has been carried out and is being carrying on. The VENUS facility will be constructed as the basic experimental platform for the neutronic study in ADS blanket. It's a zero power sub-critical neutron multiplying assembly driven by external 14MeV neutron produced by a pulsed neutron genreator. The theoretical, experimental and simulation study on nuclear data, material properties and nuclear fuel circulation related to ADS is carrying on to provide the database for ADS system analysis. the experimental high current beam injector consisted of ECR ion source, low energy beam transport system and RFQ type acceleration structure. The injector is one of the most important part of the medium energy high power proton accelerator and of worldwide interest in this community. The main results on ADS related researches and primary physical consideration of this verification system--the Venus program will be reported. (authors)
Phillips, Steven; Wilson, William H
2012-01-01
Human cognitive capacity includes recursively definable concepts, which are prevalent in domains involving lists, numbers, and languages. Cognitive science currently lacks a satisfactory explanation for the systematic nature of such capacities (i.e., why the capacity for some recursive cognitive abilities-e.g., finding the smallest number in a list-implies the capacity for certain others-finding the largest number, given knowledge of number order). The category-theoretic constructs of initial F-algebra, catamorphism, and their duals, final coalgebra and anamorphism provide a formal, systematic treatment of recursion in computer science. Here, we use this formalism to explain the systematicity of recursive cognitive capacities without ad hoc assumptions (i.e., to the same explanatory standard used in our account of systematicity for non-recursive capacities). The presence of an initial algebra/final coalgebra explains systematicity because all recursive cognitive capacities, in the domain of interest, factor through (are composed of) the same component process. Moreover, this factorization is unique, hence no further (ad hoc) assumptions are required to establish the intrinsic connection between members of a group of systematically-related capacities. This formulation also provides a new perspective on the relationship between recursive cognitive capacities. In particular, the link between number and language does not depend on recursion, as such, but on the underlying functor on which the group of recursive capacities is based. Thus, many species (and infants) can employ recursive processes without having a full-blown capacity for number and language. PMID:22514704
Effects of ad placement and type on consumer responses to podcast ads.
Ritter, Eric A; Cho, Chang-Hoan
2009-10-01
The purpose of this study was to understand the effects of podcast ad placement and podcast ad type on consumers' perceived intrusiveness, perceived irritation, attitude toward the ad, and ad avoidance. Our 2 x 2 (traditional ad vs. sponsorship by beginning vs. middle) experimental study found that sponsorships generated better consumer responses than did traditional ads and that podcast ads placed at the beginning of audio podcasts yielded better consumer responses than those placed in the middle. Implications for marketers and advertisers are discussed. PMID:19817565
From the generalized uncertainty relations on fuzzy AdS2 to the Poincare geometry
International Nuclear Information System (INIS)
The positive and discrete unitary irreps of SU(1,1) are used to construct fuzzy (Euclidean) AdS2. Two different types of uncertainty relation involving the Weyl-Heisenberg and a weaker type are studied. It is shown that there are no generalized coherent states which simultaneously minimize the Weyl-Heisenberg uncertainty relations among three non-commuting embedding coordinates of the fuzzy AdS2. However, generalized squeezed states that simultaneously satisfy the three weaker uncertainty relations do exist, and reproduce some properties of the classical AdS2. Up to a common scaling factor in terms of the irrep label, the expectation values of the non-commuting coordinates over such states are described in the same manner as the classical AdS2, in terms of the Poincare coordinates. The expectation values on the fuzzy AdS2 tend to their corresponding values in the commutative limit. (orig.)
Small plant capacity size is beautiful
Energy Technology Data Exchange (ETDEWEB)
Kharbanda, O.P.
1979-09-01
The main reason for building plants at sub-optimal sizes (with respect to production capacity) is that the market demand might be lower than forecasted, and it is more economical to run a small plant at full capacity than to run a large plant at partial capacity. Since plots of capital and operating costs per unit of production vs. plant size show rather flat minima, this can be accomplished with minimal increase in costs. The approximate optimum size of ammonia plants (tons/day) is 1000 in a developed country and 250 in a developing country; ethylene, 1200 and 500 for the same two categories, respectively; and styrene, 1000 and 400. The optimum plant size in developing countries is 0.25-0.5 times that in developed countries because costs other than capital-related, including transportation/distribution costs and other infrastructure costs, are proportionately more important in developing countries. Procedures for the economic analysis of plant size-related costs are discussed, with a tabulation of urea cost factors used as an example.
A mosaic adenovirus possessing serotype Ad5 and serotype Ad3 knobs exhibits expanded tropism
International Nuclear Information System (INIS)
The efficiency of cancer gene therapy with recombinant adenoviruses based on serotype 5 (Ad5) has been limited partly because of variable, and often low, expression by human primary cancer cells of the primary cellular-receptor which recognizes the knob domain of the fiber protein, the coxsackie and adenovirus receptor (CAR). As a means of circumventing CAR deficiency, Ad vectors have been retargeted by utilizing chimeric fibers possessing knob domains of alternate Ad serotypes. We have reported that ovarian cancer cells possess a primary receptor for Ad3 to which the Ad3 knob binds independently of the CAR-Ad5 knob interaction. Furthermore, an Ad5-based chimeric vector, designated Ad5/3, containing a chimeric fiber proteins possessing the Ad3 knob, demonstrates CAR-independent tropism by virtue of targeting the Ad3 receptor. Based on these findings, we hypothesized that a mosaic virus possessing both the Ad5 knob and the Ad3 knob on the same virion could utilize either primary receptor, resulting in expanded tropism. In this study, we generated a dual-knob mosaic virus by coinfection of 293 cells with Ad5-based and Ad5/3-based vectors. Characterization of the resultant virions confirmed the incorporation of both Ad5 and Ad3 knobs in the same particle. Furthermore, this mosaic virus was able to utilize either receptor, CAR and the Ad3 receptor, for virus attachment to cells. Enhanced Ad infectivity with the mosaic virus was shown in a panel of cell lines, with receptor profiles ranging from CAR-dominant to Ad3 receptor-dominant. Thus, this mosaic virus strategy may offer the potential to improve Ad-based gene therapy approaches by infectivity enhancement and tropism expansion
Enrollment Capacity and Technology Study
Washington Higher Education Coordinating Board, 2008
2008-01-01
The 2007-09 Appropriations Act provided funding to the Higher Education Coordinating Board (HECB) to study the state's capital facility and technology capacity. Specifically, "...state appropriation is provided solely to implement a capital facility and technology capacity study which will compare the 10-year enrollment projections with the…
Information capacity of quantum observable
Holevo, A S
2011-01-01
In this paper we consider the classical capacities of quantum-classical channels corresponding to measurement of observables. Special attention is paid to the case of continuous observables. We give the formulas for unassisted and entanglement-assisted classical capacities $C,C_{ea}$ and consider some explicitly solvable cases which give new examples of entanglement-breaking channels with $C_{ea}>C.$
Information capacity of quantum observable
Holevo, A. S.
2011-01-01
In this paper we consider the classical capacities of quantum-classical channels corresponding to measurement of observables. Special attention is paid to the case of continuous observables. We give the formulas for unassisted and entanglement-assisted classical capacities $C,C_{ea}$ and consider some explicitly solvable cases which give simple examples of entanglement-breaking channels with $C
Specific Heat Capacity of Wood
Directory of Open Access Journals (Sweden)
Kristijan Radmanović
2014-06-01
Full Text Available Specifi c heat capacity is defi ned as the amount of heat that a kilogram of a given substance is required to absorb in order to increase its temperature by one degree. The temperature of a given substance can change either at constant pressure or at constant volume, so we differentiate between specifi c heat capacity at constant pressure (cp and specifi c heat capacity at constant volume (cv. When doing research into the heat propertiesof wood, the quantity that most frequently remains constant is pressure, thus restricting our study on specifi c heat capacity to cp. This paper provides an overview of the research that has so far been carried out into the specifi c heat capacity of wood depending on the temperature and moisture content. An analytical and graphical comparison has been performed of the results published in the Wood Industry Manual (1967 (DIP, Wood Handbook (1999 (WH and work published by Deliiski (2012 (DEL.
Bandwidth Estimation For Mobile Ad hoc Network (MANET
Directory of Open Access Journals (Sweden)
Rabia Ali
2011-09-01
Full Text Available In this paper we presents bandwidth estimation scheme for MANET, which uses some components of the two methods for the bandwidth estimation: 'Hello Bandwidth Estimation 'Listen Bandwidth Estimation. This paper also gives the advantages of the proposed method. The proposed method is based on the comparison of these two methods. Bandwidth estimation is an important issue in the Mobile Ad-hoc Network (MANET because bandwidth estimation in MANET is difficult, because each host has imprecise knowledge of the network status and links change dynamically. Therefore, an effective bandwidth estimation scheme for MANET is highly desirable. Ad hoc networks present unique advanced challenges, including the design of protocols for mobility management, effective routing, data transport, security, power management, and quality-of-service (QoS provisioning. Once these problems are solved, the practical use of MANETs will be realizable.
Performance modeling of data dissemination in vehicular ad hoc networks
DEFF Research Database (Denmark)
Chaqfeh, Moumena; Lakas, Abderrahmane; Lazarova-Molnar, Sanja
2013-01-01
Vehicular Ad hoc Networks (VANETs) have become a cornerstone component of Intelligent Transportation Systems (ITS). VANET applications present a huge potential for improving road safety and travel comfort, hence the growing interest of both academia and industry. The main advantage of VANETs is its...... ad hoc nature which does not require fixed infrastructure or centralized administration. However, designing scalable information dissemination techniques for VANET applications remains a challenging task due to the inherent nature of such highly dynamic environments. Existing dissemination techniques...... often resort to simulation for performance evaluation and there are only few studies that offer mathematical modeling. In this paper we provide a comparative study of existing performance modeling approaches for data dissemination techniques designed for different VANET applications. © 2013 IEEE....
AGRICULTURAL VALUE ADDED: PROSPECTS FOR NORTH DAKOTA
Lambert, David K.; Lim, Siew Hoon; Tweeten, Kathleen M.; Leistritz, F. Larry; Wilson, William W.; McKee, Gregory J.; Nganje, William E.; DeVuyst, Cheryl Sinn; Saxowsky, David M.
2006-01-01
Introduction: This report provides an overview of the important factors affecting investments in agricultural value-added ventures. The introductory section outlines current research on factors important in the location of economic activity. Research applied to specific agricultural value-added ventures, such as food manufacturing and livestock feeding and finishing operations, are discussed. A listing of resources available to entrepreneurs considering value-added investments concludes the i...
Zhang, Jia-Lin; Cai, Rong-Gen; Yu, Hongwei
2014-01-01
We study the thermodynamics and thermodynamic geometry of a five-dimensional Schwarzschild AdS black hole in AdS 5 × S 5 spacetime by treating the cosmological constant as the number of colors in the boundary gauge theory and its conjugate quantity as the associated chemical potential. It is found that the chemical potential is always negative in the stable branch of black hole thermodynamics and it has a chance to be positive, but appears in the unstable branch. We calculate the scalar curva...
Ad-Coop Positioning System (ACPS)
DEFF Research Database (Denmark)
Frattasi, Simone; Monti, Marco
2008-01-01
In this paper, we propose an innovative solution for positioning determination in 4G wireless networks by introducing the Ad-Coop Positioning System (ACPS). The ACPS is supported by a hybrid cellular ad-hoc architecture, where the cellular network has a centralized control over the ad......-hoc connections among pairs of mobiles. Specifically, peer-to-peer (P2P) communications are exploited in a mesh fashion within cellular-established clusters for cooperation-aided localization purposes (from that, the word ad-coop is derived). The major contribution of this work is the design of the data fusion...... conventional hybrid positioning techniques in cellular networks....
Transport and metabolism of glycolic acid by Chlamydomonas reinhardtii
International Nuclear Information System (INIS)
In order to understand the excretion of glycolate from Chlamydomonas reinhardtii, the conditions affecting glycolate synthesis and metabolism were investigated. Although glycolate is synthesized only in the light, the metabolism occurs in the light and dark with greater metabolism in the light due to refixation of photorespiratory CO2. The amount of internal glycolate will affect the metabolism of externally added glycolate. When glycolate synthesis exceeds the metabolic capacity, glycolate is excreted from the cell. The transport of glycolate into the cells occurs very rapidly. Equilibrium is achieved at 40C within the time cells are pelleted by the silicone oil centrifugation technique through a layer of [14C] glycolate. Glycolate uptake does not show the same time, temperature and pH dependencies as diffusion of benzoate. Uptake can be inhibited by treatment of cells with N-ethylmaleimide and stimulated in the presence of valino-mycin/KCl. Acetate and lactate are taken up as quickly as glycolate. The hypothesis was made that glycolate is transported by a protein carrier that transports monocarboxylic acids. The equilibrium concentration of glycolate is dependent on the cell density, implying that there may be a large number of transporter sites and that uptake is limited by substrate availability
Anaerobic digester systems (ADS) for multiple dairy farms: A GIS analysis for optimal site selection
International Nuclear Information System (INIS)
While anaerobic digester systems (ADS) have been increasingly adopted by large dairy farms to generate marketable energy products, like electricity, from animal manure, there is a growing need for assessing the feasibility of regional ADS for multiple farms that are not large enough to capitalize their own ADS. Using geographical information system (GIS) software, this study first identifies potential sites in a dairy region in Vermont, based on geographical conditions, current land use types, and energy distribution infrastructure criteria, and then selects the optimal sites for a given number of ADS, based on the number of dairy farms to be served, the primary energy input to output (PEIO) ratio of ADS, and the existing transportation network. This study suggests that GIS software is a valid technical tool for identifying the potential and optimal sites for ADS. The empirical findings provide useful information for assessing the returns of alternative numbers of ADS in this region, and the research procedures can be modified easily to incorporate any changes in the criteria for this region and can be applied in other regions with different conditions and criteria. - Highlights: • This study examines the feasibility of regional ADS for multiple dairy farms. • GIS is used to identify candidate sites and optimal locations for ADS in a dairy region. • Model includes environmental, social, infrastructure, and energy return criteria. • Empirical analysis provides scenario results on 1–15 ADS in the study region. • Method could be applied to other regions with different conditions and criteria
Energy Transformed - Building Capacity in the Engineering Profession
Desha, Cheryl; Hargroves, Karlson 'Charlie'
2010-01-01
This chapter has discussed the need for urgent capacity building in the engineering profession in the area of energy efficiency, focusing on higher education institutions. We have considered the complexity of the issue within the higher education sector, where the problem is two-fold: energy efficiency knowledge and skills are not yet being taught; and the process for curriculum renewal is generally slow and ad hoc. Moreover, there are a number of organisational and curriculum influences that...
On shape dependence of holographic entanglement entropy in AdS4/CFT3
Fonda, Piermarco; Tonni, Erik
2015-01-01
We study the finite term of the holographic entanglement entropy of finite domains with smooth shapes and for four dimensional gravitational backgrounds. Analytic expressions depending on the unit vectors normal to the minimal area surface are obtained for both stationary and time dependent spacetimes. The special cases of AdS4, asymptotically AdS4 black holes, domain wall geometries and Vaidya-AdS backgrounds have been analysed explicitly. When the bulk spacetime is AdS4, the finite term is the Willmore energy of the minimal area surface viewed as a submanifold of the three dimensional flat Euclidean space. For the static spacetimes, some numerical checks involving spatial regions delimited by ellipses and non convex domains have been performed. In the case of AdS4, the infinite wedge has been also considered, recovering the known analytic formula for the coefficient of the logarithmic divergence.
1980-01-01
Transport is a fundamental component of all modern economies. Transport Policy presents a wide ranging collection of previously published articles which aim to provide the reader with an understanding of the main elements of transport policy.
Half BPS states in AdS5 x Yp,q
International Nuclear Information System (INIS)
We study a class of solutions of IIB supergravity which are asymptotically AdS5 x Yp,q. They have an R x SO(4) x SU(2) x U(1) isometry and preserve half of the 8 supercharges of the background geometry. They are described by a set of second order differential equations that we have found and analysed in a previous paper, where we studied 1/8 BPS states in the maximally supersymmetric AdS5 x S5 background. These geometries correspond to certain chiral primary operators of the N = 1 superconformal quiver theories, dual to IIB theory on AdS5 x Yp,q. We also show how to recover the AdS5 x Yp,q backgrounds by suitably doubling the number of preserved supersymmetries. We then solve the differential equations perturbatively in a large AdS5 radius expansion, imposing asymptotic AdS5 x Yp,q boundary conditions. We compute the global baryonic and mesonic charges, including the R-charge. As for the computation of the mass, i.e. the conformal dimension Δ of the dual field theory operators, which is notoriously subtle in asymptotically AdS backgrounds, we adopt the general formalism due to Wald and collaborators, which gives a finite result, and verify the relation Δ = 3R/2, demanded by the N = 1 superconformal algebra
Research on security and privacy in vehicular ad hoc networks
Zhang, Lei
2010-01-01
Los sistemas de redes ad hoc vehiculares (VANET) tienen como objetivo proporcionar una plataforma para diversas aplicaciones que pueden mejorar la seguridad vial, la eficiencia del tráfico, la asistencia a la conducción, la regulación del transporte, etc. o que pueden proveer de una mejor información y entretenimiento a los usuarios de los vehículos. Actualmente se está llevando a cabo un gran esfuerzo industrial y de investigación para desarrollar un mercado que se estima alcance en un futur...
Studies on urban vehicular ad-hoc networks
Zhu, Hongzi
2013-01-01
With the advancement of wireless technology, vehicular ad hoc networks (VANETs) are emerging as a promising approach to realizing 'smart cities' and addressing many important transportation problems such as road safety, efficiency, and convenience.This brief provides an introduction to the large trace data set collected from thousands of taxis and buses in Shanghai, the largest metropolis in China. It also presents the challenges, design issues, performance modeling and evaluation of a wide spectrum of VANET research topics, ranging from realistic vehicular mobility models and opportunistic ro
Ad Hoc Selection of Voice over Internet Streams
Macha, Mitchell G. (Inventor); Bullock, John T. (Inventor)
2014-01-01
A method and apparatus for a communication system technique involving ad hoc selection of at least two audio streams is provided. Each of the at least two audio streams is a packetized version of an audio source. A data connection exists between a server and a client where a transport protocol actively propagates the at least two audio streams from the server to the client. Furthermore, software instructions executable on the client indicate a presence of the at least two audio streams, allow selection of at least one of the at least two audio streams, and direct the selected at least one of the at least two audio streams for audio playback.
Energy Technology Data Exchange (ETDEWEB)
Urbatsch, Todd James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2015-06-15
We present an overview of radiation transport, covering terminology, blackbody raditation, opacities, Boltzmann transport theory, approximations to the transport equation. Next we introduce several transport methods. We present a section on Caseology, observing transport boundary layers. We briefly broach topics of software development, including verification and validation, and we close with a section on high energy-density experiments that highlight and support radiation transport.
Improved Energy Efficiency for Optical Transport Networks by Elastic Forward Error Correction
DEFF Research Database (Denmark)
Rasmussen, Anders; Yankov, Metodi Plamenov; Berger, Michael Stübert; Larsen, Knud J.; Ruepp, Sarah Renée
2014-01-01
In this paper we propose a scheme for reducing the energy consumption of optical links by means of adaptive forward error correction (FEC). The scheme works by performing on the fly adjustments to the code rate of the FEC, adding extra parity bits to the data stream whenever extra capacity is...... the balance between effective data rate and FEC coding gain without any disruption to the live traffic. As a consequence, these automatic adjustments can be performed very often based on the current traffic demand and bit error rate performance of the links through the network. The FEC scheme itself...... is designed to work as a transparent add-on to transceivers running the optical transport network (OTN) protocol, adding an extra layer of elastic soft-decision FEC to the built-in hard-decision FEC implemented in OTN, while retaining interoperability with existing OTN equipment. In order to...
Mazhari, N S; Bahamonde, Sebastian; Faizal, Mir; Myrzakulov, Ratbay
2016-01-01
The holographic complexity and fidelity susceptibility have been defined as new quantities dual to different volumes in AdS. In this paper, we will use these new proposals to calculate both of these quantities for a variety of interesting deformations of AdS. We obtain the holographic complexity and fidelity susceptibility for an AdS black hole, Janus solution and a solution with cylindrically symmetry, an inhomogeneous background and a hyperscaling violating background. It is observed that the holographic complexity depends on the size of the subsystem for all these solutions and the fidelity susceptibility does not any such dependence.
Entropy of Warped Taub-NUT AdS Black String via the Brick Wall Method
Lee, Chong Oh
2014-01-01
When we consider five-dimensional warped Taub-NUT AdS black string with minimally coupled massive scalar field, we calculate an entropy by using the brick wall method. In extremely light effective mass, we find the entropy is proportional to an extra dimension wave number as well as quadratically divergent in a cutoff parameter. After taking zero NUT charge, we find the entropy of warped (AdS) Schwartzshield black hole string has a similar properties in as warped Taub-NUT AdS black string.
Geometric finiteness, holography and quasinormal modes for the warped AdS3 black hole
International Nuclear Information System (INIS)
We show that there exists a precise kinematical notion of holography for the Euclidean warped AdS3 black hole. This follows from the fact that the Euclidean warped AdS3 black hole spacetime is a geometrically finite hyperbolic manifold. For such manifolds a theorem of Sullivan provides a one-to-one correspondence between the hyperbolic structure in the bulk and the conformal structure of its boundary. Using this theorem we obtain the holographic quasinormal modes for the warped AdS3 black hole.
Discrete D-branes in AdS3 and in the 2d black hole
International Nuclear Information System (INIS)
I show how the AdS2 D-branes in the Euclidean AdS3 string theory are related to the continuous D-branes in Liouville theory. I then propose new discrete D-branes in the Euclidean AdS3 which correspond to the discrete D-branes in Liouville theory. These new D-branes satisfy the appropriate shift equations. They give rise to two families of discrete D-branes in the 2d black hole, which preserve di (registered) erent symmetries
Discrete D-branes in AdS3 and in the 2d black hole
Ribault, S
2006-01-01
I show how the AdS2 D-branes in the Euclidean AdS3 string theory are related to the continuous D-branes in Liouville theory. I then propose new discrete D-branes in the Euclidean AdS3 which correspond to the discrete D-branes in Liouville theory. These new D-branes satisfy the appropriate shift equations. They give rise to two families of discrete D-branes in the 2d black hole, which preserve different symmetries.
Discrete D-branes in AdS3 and in the 2d black hole
International Nuclear Information System (INIS)
I show how the AdS2 D-branes in the Euclidean AdS3 string theory are related to the continuous D-branes in Liouville theory. I then propose new discrete D-branes in the Euclidean AdS3 which correspond to the discrete D-branes in Liouville theory. These new D-branes satisfy the appropriate shift equations. They give rise to two families of discrete D-branes in the 2d black hole, which preserve different symmetries. (orig.)
Google Advertising Tools Cashing in with AdSense and AdWords
Davis, Harold
2010-01-01
With this book, you'll learn how to take full advantage of Google AdWords and AdSense, the sophisticated online advertising tools used by thousands of large and small businesses. This new edition provides a substantially updated guide to advertising on the Web, including how it works in general, and how Google's advertising programs in particular help you make money. You'll find everything you need to work with AdWords, which lets you generate text ads to accompany specific search term results, and AdSense, which automatically delivers precisely targeted text and image ads to your website.
On circular strings in $(AdS_3 \\times S^3)_{\\varkappa}$
Banerjee, Aritra
2016-01-01
The so called one-parameter (often called $\\varkappa$) deformed $AdS$ string sigma models have attracted a lot of attention lately in the study of integrability in string theory. We construct various circular string solutions in the $(AdS_3 \\times S^3)_{\\varkappa}$ background and describe the characteristics of such solutions qualitatively. We study the Bohr-Sommerfeld like quantization for these string states to characterise the motion. Further we find a `long' string limit of such circular strings in the $\\varkappa$-deformed $AdS_3$ and find a novel dependence of the oscillation number on the energy in the next to leading order expansion.
$ \\mathcal{N} $ = 4 supersymmetric Yang-Mills theories in AdS 3
Kuzenko, Sergei M.; Gabriele Tartaglino-Mazzucchelli(School of Physics M013, The University of Western Australia, 35 Stirling Highway, Crawley W.A. 6009, Australia)
2014-01-01
For all types of $ \\mathcal{N} $ = 4 anti-de Sitter (AdS) supersymmetry in three dimensions, we construct manifestly supersymmetric actions for Abelian vector multiplets and explain how to extend the construction to the non-Abelian case. Manifestly $ \\mathcal{N} $ = 4 supersymmetric Yang-Mills (SYM) actions are explicitly given in the cases of (2,2) and critical (4,0) AdS supersymmetries. The $ \\mathcal{N} $ = 4 vector multiplets and the corresponding actions are then reduced to (2,0) AdS sup...
Using Wikipedia categories for ad hoc search
R. Kaptein; M. Koolen; J. Kamps
2009-01-01
In this paper we explore the use of category information for ad hoc retrieval in Wikipedia. We show that techniques for entity ranking exploiting this category information can also be applied to ad hoc topics and lead to significant improvements. Automatically assigned target categories are good sur
Reductio ad Contradictionem: An Algebraic Perspective
Czech Academy of Sciences Publication Activity Database
Přenosil, Adam
2016-01-01
Roč. 104, č. 3 (2016), s. 389-415. ISSN 0039-3215 R&D Projects: GA ČR GAP202/10/1826 Institutional support: RVO:67985807 Keywords : de Morgan algebras * contradiction * reductio ad contradictionem * reductio ad absurdum * four-valued logic * paraconsistent logic * inconsistency * completeness Subject RIV: BA - General Mathematics Impact factor: 0.598, year: 2014
Value added meat marketing around the globe
DEFF Research Database (Denmark)
Grebitus, Carola; Mueller Loose, Simone
In highly competitive meat markets it is important to offer value added products to consumers. Thus, we need to understand which attributes are especially valued by consumers. This track session will contribute to a better understanding of consumer preferences for value added meats across different...
Effects of Ce on damping capacity of AZ91D magnesium alloy
Institute of Scientific and Technical Information of China (English)
黄正华; 郭学锋; 张忠明
2004-01-01
The microstructures and damping capacity of AZ91D cast alloys containing various Ce contents were investigated. Damping capacity (Q-1) of the alloys was measured by cantilever beam technique, and the relationship between damping capacity and strain amplitude was investigated. The results show that Al4 Ce phase is formed in AZ91D alloy after adding a certain quantity of Ce contents, then as-cast microstructures of the alloys are refined.Meanwhile the damping capacity of the alloys is also improved. When the mass fraction of Ce is 0.7 %, the most obvious refinement effect and the maximum damping capacity can be obtained. When the damping capacity (Q-1) is 2. 728 × 10-3 , 61% increment can be obtained compared with unmodified AZ91D alloy. The damping capacity of the alloys is relative to strain amplitude, and the damping behavior can be explained by the theory of Granato and Lucke.
The concept of added value of FM
DEFF Research Database (Denmark)
Jensen, Per Anker; van der Voordt, Theo; Coenen, Christian;
2012-01-01
. The included journals were analysed over a time period of ten years, with a focus on interesting topics and less on a thematic cross-paper analysis in-depth. Originality/value: Usually the concept of added value is discussed from a mono-disciplinary point of view. The different backgrounds of the authors add......Purpose: This chapter presents research perspectives and theoretical reflections on the concept of added value of FM from a variety of academic fields. Methodology: A literature review of the most influential journals within the academic fields of Facilities Management (FM), Corporate Real Estate...... conceptualization of the concept of added value of FM is of utmost importance for further research into the added value of FM and well-considered, evidence- based Value Adding Management in practice. Research limitations: Due to limited time not all FM-related journals could be included in the literature review...
Estimating the Capacity of the Location-Based Advertising Channel
DEFF Research Database (Denmark)
Gidofalvi, Gyozo; Larsen, Hans Ravnkjær; Pedersen, Torben Bach
2008-01-01
Delivering "relevant" advertisements to consumers carrying mobile devices is regarded by many as one of the most promising mobile business opportunities. The relevance of a mobile ad depends on at least two factors: (1) the proximity of the mobile consumer to the product or service being advertised......, and (2) the match between the product or service and the interest of the mobile consumer. The interest of the mobile consumer can be either explicit (expressed by the mobile consumer) or implicit (inferred from user characteristics). This paper tries to empirically estimate the capacity of the mobile...... advertising channel, i.e., the number of relevant ads that can be delivered to mobile consumers. The estimations are based on a simulated mobile consumer population and simulated mobile ads. Both of the simulated data sets are realistic and derived based on real world data sources about population geo...
Energy Technology Data Exchange (ETDEWEB)
Freivogel, Ben; /Stanford U., Phys. Dept. /LBL, Berkeley; Hubeny, Veronika E.; /LBL, Berkeley /Durham U., Dept. of Math.; Maloney, Alexander; /Stanford U., Phys. Dept.; Myers, Rob; /Perimeter Inst. Theor. Phys. /Waterloo U.; Rangamani, Mukund; /LBL, Berkeley /Durham U., Dept. of Math.; Shenker, Stephen; /Stanford U., Phys. Dept.
2005-10-07
We study the realization of inflation within the AdS/CFT correspondence. We assume the existence of a string landscape containing at least one stable AdS vacuum and a (nearby) metastable de Sitter state. Standard arguments imply that the bulk physics in the vicinity of the AdS minimum is described by a boundary CFT. We argue that large enough bubbles of the dS phase, including those able to inflate, are described by mixed states in the CFT. Inflating degrees of freedom are traced over and do not appear explicitly in the boundary description. They nevertheless leave a distinct imprint on the mixed state. Analytic continuation allows us, in principle, to recover a large amount of nonperturbatively defined information about the inflating regime. Our work also shows that no scattering process can create an inflating region, even by quantum tunneling, since a pure state can never evolve into a mixed state under unitary evolution.We study the realization of inflation within the AdS/CFT correspondence. We assume the existence of a string landscape containing at least one stable AdS vacuum and a (nearby) metastable de Sitter state. Standard arguments imply that the bulk physics in the vicinity of the AdS minimum is described by a boundary CFT. We argue that large enough bubbles of the dS phase, including those able to inflate, are described by mixed states in the CFT. Inflating degrees of freedom are traced over and do not appear explicitly in the boundary description. They nevertheless leave a distinct imprint on the mixed state. Analytic continuation allows us, in principle, to recover a large amount of nonperturbatively defined information about the inflating regime. Our work also shows that no scattering process can create an inflating region, even by quantum tunneling, since a pure state can never evolve into a mixed state under unitary evolution.
Using Road IDs to Enhance Clustering in Vehicular Ad hoc Networks
Hadded, Mohamed; Muhlethaler, Paul; Zagrouba, Rachid; Laouiti, Anis; Saidane, Leila Azouz
2015-01-01
—Vehicular ad hoc networks (VANETs) where vehicles act as mobile nodes is an instance of Mobile Ad hoc NETworks (MANETs), which are essentially developed for intelligent transportation systems. A challenging problem when designing communication protocols in VANETs is coping with high vehicle mobility, which causes frequent changes in the network topology and leads to frequent breaks in communication. The clustering technique is being developed to reduce the impact of mobility between neighbor...
Energy Technology Data Exchange (ETDEWEB)
OLSON,CRAIG L.
2000-05-17
Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system.
Opportunities for increasing domestic added value ofcocoa through trade regulation
Directory of Open Access Journals (Sweden)
Bambang Drajat
2011-08-01
Full Text Available The operation of multinational companies on cocoa bean trade in Indonesia related to the liberalization policy on trade and investment in Indonesia permits for multinational companies to operate in Indonesia and liable to buy cocoa bean directly from farmers. The problem encountered is the domestic market liberalization gives rise to changes in market power and results ini the dominant position of multinational companies. This research aimed to (i analyze the impact of the exercise of market power by cocoa multinational company, (ii to analyze the possibility of deregulation of cocoa bean domestic trade, and (iii to estimate the potential increase in added value of cocoa down-stream industry as a result of deregulation. Some steps of research conducted includes (i desk research, (ii field survey by interviewing samples of farmers, traders, exporters, processors, as well as other business participants, (iii special interviews with key persons related to regulation as well as deregulation of domestic trade and down-stream industry development, and (iv focussed group discussion involving related stakeholders of cocoa. The results showed that the impact of the exercise of market power by multinational companies refers to the decreasing market shares of national companies from 2007 to 2009. Based on the market power domination of multinational companies in one side and the lack of down-stream industry development in the other side, there is a possibility to deregulate the above policy by continuing the new regulation (export tax of cocoa beans, directing multinational exporters toward downstream industry by partnership with domestic-idle capacity processing industry and import tariff escalation for processed cocoa. By the new regulation, the opportunity to increase domestic added value becomes greater. This cocoa down-stream industry development will increase the potential domestic added value at least 10%. Key words : Liberalization, deregulation
Neuropsychological assessment of mental capacity.
Sullivan, Karen
2004-09-01
The assessment of mental capacity to assist legal determinations of competency is potentially a growth area for neuropsychology, although to date neuropsychologists have published relatively little in this area. In this paper a systematic review of methods used to assess capacity is presented, including coverage of specialized tests and interviews used for this purpose. A neuropsychological model for conducting capacity assessments is proposed. This model involves comprehensive assessment of a wide range of cognitive abilities as well as assessment of specific skills and knowledge related to the type of capacity being assessed. The purpose of proposing this model is to stimulate further discussion and debate about the contribution neuropsychologists might make in this area. PMID:15673234
SEDIMENT-REMOVING CAPACITY AND RIVER MOTION DYNAMICS
Institute of Scientific and Technical Information of China (English)
Zhao-Yin WANG; Yongsheng WU
2001-01-01
Unsteady flow in fluvial rivers scours or deposits sediment, and exhibits sediment-removing capaciiy,which is defined as the capacity of the flow to remove sediment from per unit length of a river channel to other places per time. Differing from the well-defined sediment-carrying capacity, which is the feature of the mean flow and explains how much sediment load the flow can transport through the channel, the sediment-removing capacity is the feature of unsteady, non-equilibrium flow and represents the capability of the flow to change the channel shape and location. Measurement of the sediment-removing capacity was performed at 12 cross sections of the wandering lower Yellow River. Analysis demonstrates that the removing capacity depends mainly on the fluctuation intensity of the flow discharge. The power spectrum of discharge is presented with Fourier transformation and it revealed the mechanism of high measurement frequency-high sediment removing capacity. The movement of a river channel within the fluvial plain is defined as the river motion. The patterns of river motion are aggradation, degradation, widening,translation, rotation, wandering, bifurcation, and migration from one channel to another channel. The speed of the river motion is given as a function of the sediment-removing capacity.
Fluctuation-driven capacity distribution in complex networks
International Nuclear Information System (INIS)
Maximizing robustness and minimizing cost are common objectives in the design of infrastructure networks. However, most infrastructure networks evolve and operate in a highly decentralized fashion, which may significantly impact the allocation of resources across the system. Here, we investigate this question by focusing on the relation between capacity and load in different types of real-world communication and transportation networks. We find strong empirical evidence that the actual capacity of the network elements tends to be similar to the maximum available capacity, if the cost is not strongly constraining. As more weight is given to the cost, however, the capacity approaches the load nonlinearly. In particular, all systems analyzed show larger unoccupied portions of the capacities on network elements subjected to smaller loads, which is in sharp contrast with the assumptions involved in (linear) models proposed in previous theoretical studies. We describe the observed behavior of the capacity-load relation as a function of the relative importance of the cost by using a model that optimizes capacities to cope with network traffic fluctuations. These results suggest that infrastructure systems have evolved under pressure to minimize local failures, but not necessarily global failures that can be caused by the spread of local damage through cascading processes
Heat capacities and thermodynamic properties of annite (aluminous iron biotite)
Hemingway, B.S.; Robie, R.A.
1990-01-01
The heat capacities have been measured between 7 and 650 K by quasi-adiabatic calorimetry and differential scanning calorimetry. At 298.15 K and 1 bar, the calorimetric entropy for our sample is 354.9??0.7 J/(mol.K). A minimum configurational entropy of 18.7 J/(mol.K) for full disorder of Al/Si in the tetrahedral sites should be added to the calorimetric entropy for third-law calculations. The heat capacity equation [Cp in units of J/mol.K)] Cp0 = 583.586 + 0.075246T - 3420.60T-0.5 - (4.4551 ?? 106)T-2 fits the experimental and estimated heat capacities for our sample (valid range 250 to 1000 K) with an average deviation of 0.37%. -from Authors
Affine transformations and analytic capacities
Dowling, Thomas; O'Farrell, Anthony G.
1995-01-01
Analytic capacities are set functions defined on the plane which may be used in the study of removable singularities, boundary smoothness and approximation of analytic functions belonging to some function space. The symmetric concrete Banach spaces form a class of function spaces that include most spaces usually studied. The Beurling transform is a certain singular integral operator that has proved useful in analytic function theory. It is shown that the analytic capacity associated to ...
Maximizing the optical network capacity.
Bayvel, Polina; Maher, Robert; Xu, Tianhua; Liga, Gabriele; Shevchenko, Nikita A; Lavery, Domaniç; Alvarado, Alex; Killey, Robert I
2016-03-01
Most of the digital data transmitted are carried by optical fibres, forming the great part of the national and international communication infrastructure. The information-carrying capacity of these networks has increased vastly over the past decades through the introduction of wavelength division multiplexing, advanced modulation formats, digital signal processing and improved optical fibre and amplifier technology. These developments sparked the communication revolution and the growth of the Internet, and have created an illusion of infinite capacity being available. But as the volume of data continues to increase, is there a limit to the capacity of an optical fibre communication channel? The optical fibre channel is nonlinear, and the intensity-dependent Kerr nonlinearity limit has been suggested as a fundamental limit to optical fibre capacity. Current research is focused on whether this is the case, and on linear and nonlinear techniques, both optical and electronic, to understand, unlock and maximize the capacity of optical communications in the nonlinear regime. This paper describes some of them and discusses future prospects for success in the quest for capacity. PMID:26809572
Energy Technology Data Exchange (ETDEWEB)
Keane, Andrew; Milligan, Michael; Dent, Chris; Hasche, Bernhard; DAnnunzio, Claudine; Dragoon, Ken; Holttinen, Hannele; Samaan, Nader A.; Soder, Lennart; O' Malley, Mark J.
2011-05-04
Power systems are planned such that they have adequate generation capacity to meet the load, according to a defined reliability target. The increase in the penetration of wind generation in recent years has led to a number of challenges for the planning and operation of power systems. A key metric for system adequacy is the capacity value of generation. The capacity value of a generator is the contribution that a given generator makes to overall system adequacy. The variable and stochastic nature of wind sets it apart from conventional energy sources. As a result, the modeling of wind generation in the same manner as conventional generation for capacity value calculations is inappropriate. In this paper a preferred method for calculation of the capacity value of wind is described and a discussion of the pertinent issues surrounding it is given. Approximate methods for the calculation are also described with their limitations highlighted. The outcome of recent wind capacity value analyses in Europe and North America are highlighted with a description of open research questions also given.
Comments Concerning the CFT Description of Small Objects in AdS
Hubeny, V.; Susskind, L.; Toumbas, N.
2000-01-01
In this paper we resolve a contradiction posed in a recent paper by Horowitz and Hubeny. The contradiction concerns the way small objects in AdS space are described in the holographic dual CFT description.
A Grassmann Path From AdS$_3$ to Flat Space
Krishnan, Chethan; Roy, Shubho
2013-01-01
We show that interpreting the inverse AdS$_3$ radius $1/l$ as a Grassmann variable results in a formal map from gravity in AdS$_3$ to gravity in flat space. The underlying reason for this is the fact that $ISO(2,1)$ is the Inonu-Wigner contraction of $SO(2,2)$. We show how this works for the Chern-Simons actions, demonstrate how the general (Banados) solution in AdS$_3$ maps to the general flat space solution, and how the Killing vectors, charges and the Virasoro algebra in the Brown-Henneaux case map to the corresponding quantities in the BMS$_3$ case. Our results straightforwardly generalize to the higher spin case: the recently constructed flat space higher spin theories emerge automatically in this approach from their AdS counterparts. We conclude with a discussion of singularity resolution in the BMS gauge as an application.
Two gravitational shock waves on the AdS3 brane
International Nuclear Information System (INIS)
A gravitational shock wave is a solution to Einstein equations describing the gravitational field of a massless particle. We obtain such a geometry for a particle moving on a AdS3 brane embedded in a AdS4 bulk (the lower dimensional version of the ''locally localized gravity'' model of Karch and Randall). In order to do this, we use two different techniques. First, we solve directly Einstein equations sourced by a massless particle. Then we boost to the speed of light the AdS3 brane black hole solution of Emparan et al. while sending its mass parameter to zero. Surprisingly, we obtain two different results. We discuss the origin of these two different solutions both in the bulk and in the CFT picture. As a by-product, we derive the expression for the shock wave associated to a transversally accelerating particle in AdS4
Boundary three-point function on AdS2 D-branes
International Nuclear Information System (INIS)
Using the H3+-Liouville relation, I explicitly compute the boundary three-point function on AdS2 D-branes in H3+, and check that it exhibits the expected symmetry properties and has the correct geometrical limit. I then find a simple relation between this boundary three-point function and certain fusing matrix elements, which suggests a formal correspondence between the AdS2 D-branes and discrete representations of the symmetry group. Concluding speculations deal with the fuzzy geometry of AdS2 D-branes, strings in the Minkowskian AdS3, and the hypothetical existence of new D-branes in H3+
Boundary three-point function on AdS2 D-branes
Ribault, Sylvain
2008-01-01
Using the H3+-Liouville relation, I explicitly compute the boundary three-point function on AdS2 D-branes in H3+, and check that it exhibits the expected symmetry properties and has the correct geometrical limit. I then find a simple relation between this boundary three-point function and certain fusing matrix elements, which suggests a formal correspondence between the AdS2 D-branes and discrete representations of the symmetry group. Concluding speculations deal with the fuzzy geometry of AdS2 D-branes, strings in the Minkowskian AdS3, and the hypothetical existence of new D-branes in H3+.
Impaired cognition in depression and Alzheimer (AD: a gradient from depression to depression in AD
Directory of Open Access Journals (Sweden)
Narahyana Bom de Araujo
2014-09-01
Full Text Available Objective To assess cognition in major depressed (MD, Alzheimer's disease (AD, and depression in AD elderly. Method Subjects were evaluated by Mini Mental, Rey Auditory Verbal Learning Test, Rey Complex Figure, Digit Span, Similarities, Trail Making A/B, Verbal Fluency and Stroop. One-way ANOVA and multivariate models were used to compare the performance of each group on neuropsychological tests. Results We evaluated 212 subjects. Compared to MD, attention, working memory, processing speed and recall showed significantly better in controls. Controls showed significantly higher performance in all cognitive measures, except in attention compared to AD. Verbal fluency, memory, processing speed and abstract reasoning in MD was significantly higher compared to AD. AD was significantly better in general cognitive state than depression in AD. All other cognitive domains were similar. Conclusion A decreasing gradient in cognition appeared from the control to depression in AD, with MD and AD in an intermediate position.
On Critical Massive (Super)Gravity in adS3
Bergshoeff, Eric A; Rosseel, Jan; Sezgin, Ergin; Townsend, Paul K
2010-01-01
We review the status of three-dimensional "general massive gravity" (GMG) in its linearization about an anti-de Sitter (adS) vacuum, focusing on critical points in parameter space that yield generalizations of "chiral gravity". We then show how these results extend to N=1 super-GMG, expanded about a supersymmetric adS vacuum, and also to the most general `curvature-squared' N=1 supergravity model.