WorldWideScience

Sample records for bottlenecks

  1. Logistics bottlenecks

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-09-15

    Many of the vulnerabilities to Energy Access, Energy Security, and Environmental Sustainability result from impediments to reaching a global demand-supply balance, as well as local balances, for various energy sources and carriers. Vulnerabilities result from multiple reasons: regional imbalances of energy production and consumption, the bulky character of the majority of energy fuels, the virtual necessity of electricity consumption following its production, among others. To detect and prioritize respective 'bottlenecks' across energy carriers, they have to be measured. In this report, production, consumption, exports, and imports were measured across all major energy carriers for seven key regions of the world for three time frames-2008, 2020, and 2050. Imbalances between production and consumption form bottlenecks in each region.

  2. When is a bottleneck a bottleneck?

    CERN Document Server

    Schadschneider, Andreas; Popkov, Vladislav

    2015-01-01

    Bottlenecks, i.e. local reductions of capacity, are one of the most relevant scenarios of traffic systems. The asymmetric simple exclusion process (ASEP) with a defect is a minimal model for such a bottleneck scenario. One crucial question is "What is the critical strength of the defect that is required to create global effects, i.e. traffic jams localized at the defect position". Intuitively one would expect that already an arbitrarily small bottleneck strength leads to global effects in the system, e.g. a reduction of the maximal current. Therefore it came as a surprise when, based on computer simulations, it was claimed that the reaction of the system depends in non-continuous way on the defect strength and weak defects do not have a global influence on the system. Here we reconcile intuition and simulations by showing that indeed the critical defect strength is zero. We discuss the implications for the analysis of empirical and numerical data.

  3. Economic analysis of production bottlenecks

    Directory of Open Access Journals (Sweden)

    Lawrence Stephen R.

    1995-01-01

    Full Text Available The management of bottlenecks has become a central topic in the planning and control of production systems. In this paper, we critically analyze bottlenecks from an economic perspective. Using a queueing network model, we demonstrate that bottlenecks are inevitable when there are differences in job arrival rates, processing rates, or costs of productive resources. These differences naturally lead to the creation of bottlenecks both for facilities design and demand planning problems. To evaluate bottlenecks from an economic perspective, we develop the notion of an “economic bottleneck,” which defines resources as bottlenecks based on economic, rather than physical, characteristics.

  4. Uncorking the bottleneck

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-10-01

    CoeClerici Logistics' floating terminals have helped clients all over the world overcome a variety of infrastructure bottlenecks including limited draft or insufficient storage capacity. The vessel 'Bulk Irony' is a self-propelled 13,000 dwt transhipper built for Lucchini Steel's mill at Piombino, Italy for import of coal, coke and ores and export of steel products. The large 'Bulk Wayuu' coal terminal in the Lake of Maracaibo, Venezuela serves Carbones del Guasare, Venezuela's largest coal producer.

  5. The Constrained Bottleneck Transportation Problem

    OpenAIRE

    Peerayuth Charnsethikul; Saeree Svetasreni

    2007-01-01

    Two classes of the bottleneck transportation problem with an additional budget constraint are introduced. An exact approach was proposed to solve both problem classes with proofs of correctness and complexity. Moreover, the approach was extended to solve a class of multi-commodity transportation network with a special case of the multi-period constrained bottleneck assignment problem.

  6. Effects of Bottlenecks in Vehicle Traffic

    CERN Document Server

    Yamamoto, S; Tadaki, S; Yamamoto, Syohei; Hieida, Yasuhiro; Tadaki, Shin-ichi

    2006-01-01

    Traffic congestion is usually observed at the upper streams of bottlenecks like tunnels. Congestion appears as stop-and-go waves and high density uniform flow. We perform simulations of traffic flow with a bottleneck using the coupled map optimal velocity model. The bottleneck is expressed as a road segment with speed reduction. The emergence of stop-and-go waves depends on the speed reduction in the bottleneck. A phenomenological theory of bottleneck effects is constructed.

  7. Effects of Bottlenecks on Vehicle Traffic

    OpenAIRE

    Yamamoto, Syohei; Hieida, Yasuhiro; Tadaki, Shin-ichi

    2006-01-01

    Traffic congestion is usually observed at the upper streams of bottlenecks such as tunnels. Congestion appears as stop-and-go waves and high density uniform flow. We perform simulations of traffic flow with a bottleneck using the coupled map optimal velocity model. The bottleneck is expressed as a road segment with speed reduction. The speed reduction in the bottleneck controls the emergence of stop-and-go waves. A phenomenological theory of bottleneck effects is constructed.

  8. MODIFIED BOTTLENECK-BASED PROCEDURE FOR LARGE-SCALE FLOW-SHOP SCHEDULING PROBLEMS WITH BOTTLENECK

    Institute of Scientific and Technical Information of China (English)

    ZUO Yan; GU Hanyu; XI Yugeng

    2006-01-01

    A new bottleneck-based heuristic for large-scale flow-shop scheduling problems with a bottleneck is proposed, which is simpler but more tailored than the shifting bottleneck (SB)procedure. In this algorithm, a schedule for the bottleneck machine is first constructed optimally and then the non-bottleneck machines are scheduled around the bottleneck schedule by some effective dispatching rules. Computational results show that the modified bottleneck-based procedure can achieve a tradeoff between solution quality and computational time comparing with SB procedure for medium-size problems. Furthermore it can obtain a good solution in quite short time for large-scale scheduling problems.

  9. Dynamic Prediction Method of Production Logistics Bottleneck Based on Bottleneck Index

    Institute of Scientific and Technical Information of China (English)

    LIU Mingzhou; TANG Juan; GE Maogen; JIANG Zengqiang; HU Jing; LING Lin

    2009-01-01

    In modern manufacturing pattern, there are many uncertain factors in the modern manufacturing process, such as changes of product attribute, changes of manufacturing resources' state, and so on, which cause production logistics bottleneck frequently shift, and make decisions of production planning and control based on formed bottleneck deviated from practical production process. Considering these factors, present researches mainly apply afterwards control to optimize production process to passively adapt to bottleneck changes. If the direction of bottleneck shifting can be accurately forecasted, the transition from afterwards control of chasing bottleneck to beforehand control can be realized. Therefore, aiming at the phenomenon of production logistics bottleneck shifting under uncertain manufacturing circumstances, this paper starts off with dynamic property of capability and requirement and then builds the concepts of bottleneck degree and bottleneck index to describe dynamic bottleneck characteristic of production unit;taken production capability, production load and quality assurance capability into consideration, mathematical model of bottleneck index is established to measure bottleneck degree accurately, consequently, quantitative research on mechanism of production logistics shifting is achieved. Based on bottleneck index, the prediction model of production logistics bottleneck is founded to predict dynamic change of bottleneck accurately. Finally, an example of forecasting and monitoring the production logistics bottleneck in one manufacturing shop is given to testify the validation and practicability of the prediction method.

  10. BOTTLENECKS IN PRODUCTION NETWORKS: AN OVERVIEW

    Institute of Scientific and Technical Information of China (English)

    Yongcai WANG; Qianchuan ZHAO; Dazhong ZHENG

    2005-01-01

    Bottlenecks, the key ingredients for improving the performances of the production networks,have been profoundly studied during the last decade. Yet, because of the complexity of the research results, there is still a significant gap between theory and practice. In this paper, we review various bottleneck definitions, detection methods and the asymptotic results and provide a practical guidance for recognizing and utilizing the bottlenecks in production networks. Queueing theory works as the mathematical foundation in our study. Various definitions of the bottlenecks are classified as either Performance in Processing (PIP) based or sensitivity based definitions, which reflect the preferences of the managers. Detection methods are surveyed closely based on the definitions. These methods are used to recognize the bottlenecks and to provide diagnosis results to managers. Comparisons show that different detection methods may lead to vastly different conclusions. The recognition of the bottlenecks has another advantage: the ultimate phenomena of the bottlenecks can greatly reduce the computation complexity in calculating the system performances. Bottlenecks based approximation and asymptotic results are studied to exhibit the contribution of bottlenecks in performance estimation and theoretical analysis.

  11. Analytical approach to continuous and intermittent bottleneck flows

    DEFF Research Database (Denmark)

    Helbing, D.; Johansson, A.; Mathiesen, Joachim Kaj; Jensen, M.H.; Hansen, A.

    2006-01-01

    Many-particle-inspired theory, Continuous and Intermittent Bottleneck Flows Udgivelsesdato: Oct. 20......Many-particle-inspired theory, Continuous and Intermittent Bottleneck Flows Udgivelsesdato: Oct. 20...

  12. Cloud Technology May Widen Genomic Bottleneck - TCGA

    Science.gov (United States)

    Computational biologist Dr. Ilya Shmulevich suggests that renting cloud computing power might widen the bottleneck for analyzing genomic data. Learn more about his experience with the Cloud in this TCGA in Action Case Study.

  13. The bottleneck of second language acquisition

    OpenAIRE

    Slabakova, Roumyana

    2014-01-01

    Explaining why some linguistic features and constructions are easy or difficult to acquire in a second language has become a prominent current concern in generative second language acquisition (SLA) research. Based on a comparison of findings on the L2 acquisition of functional morphology, syntax, semantics and pragmatics, the Bottleneck Hypothesis argues that functional morphemes and their features are the bottleneck of L2 acquisition; acquisition of universal syntax, semantics and pragmatic...

  14. Tracing Road Network Bottleneck by Data Driven Approach

    Science.gov (United States)

    Qi, Hongsheng; Liu, Meiqi; Zhang, Lihui; Wang, Dianhai

    2016-01-01

    Urban road congestions change both temporally and spatially. They are essentially caused by network bottlenecks. Therefore, understanding bottleneck dynamics is critical in the goal of reasonably allocating transportation resources. In general, a typical bottleneck experiences the stages of formation, propagation and dispersion. In order to understand the three stages of a bottle neck and how the bottleneck moves on a road network, traffic flow data can be used to reconstruct these dynamics. However, raw traffic flow data is usually flawed in many ways. For instance some portion of data may be missing due to the failure of data collection devices, or some random factors in the data make it hard to identify real bottlenecks. In this paper a “user voting method” is proposed to deal with such raw-data-related issues. In this method, road links are ranked according to the weighed sum of certain performance measures and the links that are ranked relatively high are regarded as recurrent bottlenecks in a network, and several bottlenecks form a bottleneck area. A series of bottleneck parameters can be defined based on the identified bottleneck areas, such as bottleneck coverage, bottleneck link length, etc. Identifying bottleneck areas and calculating the bottleneck parameters for each time interval can reflect the evolution of the bottlenecks and also help trace how the bottlenecks move. PMID:27228150

  15. Tracing Road Network Bottleneck by Data Driven Approach.

    Science.gov (United States)

    Qi, Hongsheng; Liu, Meiqi; Zhang, Lihui; Wang, Dianhai

    2016-01-01

    Urban road congestions change both temporally and spatially. They are essentially caused by network bottlenecks. Therefore, understanding bottleneck dynamics is critical in the goal of reasonably allocating transportation resources. In general, a typical bottleneck experiences the stages of formation, propagation and dispersion. In order to understand the three stages of a bottle neck and how the bottleneck moves on a road network, traffic flow data can be used to reconstruct these dynamics. However, raw traffic flow data is usually flawed in many ways. For instance some portion of data may be missing due to the failure of data collection devices, or some random factors in the data make it hard to identify real bottlenecks. In this paper a "user voting method" is proposed to deal with such raw-data-related issues. In this method, road links are ranked according to the weighed sum of certain performance measures and the links that are ranked relatively high are regarded as recurrent bottlenecks in a network, and several bottlenecks form a bottleneck area. A series of bottleneck parameters can be defined based on the identified bottleneck areas, such as bottleneck coverage, bottleneck link length, etc. Identifying bottleneck areas and calculating the bottleneck parameters for each time interval can reflect the evolution of the bottlenecks and also help trace how the bottlenecks move. PMID:27228150

  16. Tracing Road Network Bottleneck by Data Driven Approach.

    Directory of Open Access Journals (Sweden)

    Hongsheng Qi

    Full Text Available Urban road congestions change both temporally and spatially. They are essentially caused by network bottlenecks. Therefore, understanding bottleneck dynamics is critical in the goal of reasonably allocating transportation resources. In general, a typical bottleneck experiences the stages of formation, propagation and dispersion. In order to understand the three stages of a bottle neck and how the bottleneck moves on a road network, traffic flow data can be used to reconstruct these dynamics. However, raw traffic flow data is usually flawed in many ways. For instance some portion of data may be missing due to the failure of data collection devices, or some random factors in the data make it hard to identify real bottlenecks. In this paper a "user voting method" is proposed to deal with such raw-data-related issues. In this method, road links are ranked according to the weighed sum of certain performance measures and the links that are ranked relatively high are regarded as recurrent bottlenecks in a network, and several bottlenecks form a bottleneck area. A series of bottleneck parameters can be defined based on the identified bottleneck areas, such as bottleneck coverage, bottleneck link length, etc. Identifying bottleneck areas and calculating the bottleneck parameters for each time interval can reflect the evolution of the bottlenecks and also help trace how the bottlenecks move.

  17. Identification and optimization of traffic bottleneck with signal timing

    OpenAIRE

    Shaoxin Yuan; Xiangmo Zhao; Yisheng An

    2014-01-01

    In urban transportation network, traffic congestion is likely to occur at traffic bottlenecks. The signal timing at intersections together with static properties of left-turn and straight-through lanes of roads are two significant factors causing traffic bottlenecks. A discrete-time model of traffic bottleneck is hence developed to analyze these two factors, and a bottleneck indicator is introduced to estimate the comprehensive bottleneck degree of individual road in regional transportation n...

  18. Potential performance bottleneck in Linux TCP

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Wenji; Crawford, Matt; /Fermilab

    2006-12-01

    TCP is the most widely used transport protocol on the Internet today. Over the years, especially recently, due to requirements of high bandwidth transmission, various approaches have been proposed to improve TCP performance. The Linux 2.6 kernel is now preemptible. It can be interrupted mid-task, making the system more responsive and interactive. However, we have noticed that Linux kernel preemption can interact badly with the performance of the networking subsystem. In this paper we investigate the performance bottleneck in Linux TCP. We systematically describe the trip of a TCP packet from its ingress into a Linux network end system to its final delivery to the application; we study the performance bottleneck in Linux TCP through mathematical modeling and practical experiments; finally we propose and test one possible solution to resolve this performance bottleneck in Linux TCP.

  19. New insights into pedestrian flow through bottlenecks

    CERN Document Server

    Seyfried, A; Klingsch, W; Passon, O; Rupprecht, T; Steffen, B; Boltes, Maik; Klingsch, Wolfram; Passon, Oliver; Rupprecht, Tobias; Seyfried, Armin; Steffen, Bernhard

    2007-01-01

    Capacity estimation is an important tool for the design and dimensioning of pedestrian facilities. The literature contains different procedures and specifications which show considerable differences with respect to the estimated flow values. Moreover do new experimental data indicate a stepwise growing of the capacity with the width and thus challenge the validity of the specific flow concept. To resolve these differences we have studied experimentally the unidirectional pedestrian flow through bottlenecks under laboratory conditions. The time development of quantities like individual velocities, density and individual time gaps in bottlenecks of different width is presented. The data show a linear growth of the flow with the width. The comparison of the results with experimental data of other authors indicates that the basic assumption of the capacity estimation for bottlenecks has to be revised. In contradiction with most planning guidelines our main result is, that a jam occurs even if the incoming flow do...

  20. Shear bands as bottlenecks in force transmission

    Science.gov (United States)

    Tordesillas, Antoinette; Pucilowski, Sebastian; Tobin, Steven; Kuhn, Matthew R.; Andò, Edward; Viggiani, Gioacchino; Druckrey, Andrew; Alshibli, Khalid

    2015-06-01

    The formation of shear bands is a key attribute of degradation and failure in soil, rocks, and many other forms of amorphous and crystalline materials. Previous studies of dense sand under triaxial compression and two-dimensional analogues from simulations have shown that the ultimate shear band pattern may be detected in the nascent stages of loading, well before the band's known nucleation point (i.e., around peak stress ratio), as reported in the published literature. Here we construct a network flow model of force transmission to identify the bottlenecks in the contact networks of dense granular media: triaxial compression of Caicos ooid and Ottawa sand and a discrete element simulation of simple shear. The bottlenecks localise in the nascent stages of loading —in the location where the persistent shear band ultimately forms. This corroborates recent findings on vortices that suggest localised failure is a progressive process of degradation, initiating early in the loading history at sites spanning the full extent, yet confined to a subregion, of the sample. Bottlenecks are governed by the local and global properties of the sample fabric and the grain kinematics. Grains with large rotations and/or contacts having minimal load-bearing capacities per se do not identify the bottlenecks early in the loading history.

  1. Performance Bottlenecks in Digital Movie Systems

    OpenAIRE

    Keller, Ralf; Effelsberg, Wolfgang; Lamparter, Bernd

    1993-01-01

    Digital movie systems offer great perspectives for multimedia applications. But the large amounts of data involved and the demand for isochronous transmission and playback are also great challenges for the designers of a new generation of file systems, database systems, operating systems, window systems, video encoder/decoder and networks. Today's research prototypes of digital movie systems suffer from severe performance bottlenecks, resulting in small movie windows, low frame rates or bad i...

  2. Teleworking and Congestion: A Dynamic Bottleneck Analysis

    OpenAIRE

    Gubins, Sergejs; Verhoef, Erik T.

    2011-01-01

    We analyze the welfare effects of part-day teleworking on road traffic congestion in the context of Vickrey's dynamic bottleneck model. Endogenous decisions to become equipped with a teleworking-enabling technology change the scheduling of arrival times at work for equipped drivers and, due to congestion externalities, affects travel costs of all drivers. We show that even costless teleworking might be marginally welfare reducing, after reaching the optimal penetration level, as an equipped d...

  3. Individual Microscopic Results Of Bottleneck Experiments

    CERN Document Server

    Bukáček, Marek; Krbálek, Milan

    2016-01-01

    This contribution provides microscopic experimental study of pedestrian motion in front of the bottleneck, explains the high variance of individual travel time by the statistical analysis of trajectories. The analysis shows that this heterogeneity increases with increasing occupancy. Some participants were able to reach lower travel time due more efficient path selection and more aggressive behavior within the crowd. Based on this observations, linear model predicting travel time with respect to the aggressiveness of pedestrian is proposed.

  4. DYNAMIC BOTTLENECKS IN HANDLING AND STORAGE SYSTEMS

    OpenAIRE

    PANOVA YULIA; HILMOLA OLLI-PEKKA

    2015-01-01

    The development of industrial engineering and production systems is manifested under the demand of Russian customers in the current economic and political situation, e.g. deprivation from several import markets. In these circumstances, issues related to the formation of process systems are gaining their importance. The article considers the objective of reaching the smooth and continuous material flow in the handling and storage system of the plant, as well as the problems of bottlenecks opti...

  5. Deep Bottleneck Feature for Image Classification

    OpenAIRE

    Song, Yan; McLoughlin, Ian Vince; Dai, Lirong

    2015-01-01

    Effective image representation plays an important role for image classification and retrieval. Bag-of-Features (BoF) is well known as an effective and robust visual representation. However, on large datasets, convolutional neural networks (CNN) tend to perform much better, aided by the availability of large amounts of training data. In this paper, we propose a bag of Deep Bottleneck Features (DBF) for image classification, effectively combining the strengths of a CNN within a BoF framework. T...

  6. Bottlenecks to coral recovery in the Seychelles

    Science.gov (United States)

    Chong-Seng, K. M.; Graham, N. A. J.; Pratchett, M. S.

    2014-06-01

    Processes that affect recovery of coral assemblages require investigation because coral reefs are experiencing a diverse array of more frequent disturbances. Potential bottlenecks to coral recovery include limited larval supply, low rates of settlement, and high mortality of new recruits or juvenile corals. We investigated spatial variation in local abundance of scleractinian corals in the Seychelles at three distinct life history stages (recruits, juveniles, and adults) on reefs with differing benthic conditions. Following widespread coral loss due to the 1998 bleaching event, some reefs are recovering (i.e., relatively high scleractinian coral cover: `coral-dominated'), some reefs have low cover of living macrobenthos and unconsolidated rubble substrates (`rubble-dominated'), and some reefs have high cover of macroalgae (`macroalgal-dominated'). Rates of coral recruitment to artificial settlement tiles were similar across all reef conditions, suggesting that larval supply does not explain differential coral recovery across the three reef types. However, acroporid recruits were absent on macroalgal-dominated reefs (0.0 ± 0.0 recruits tile-1) in comparison to coral-dominated reefs (5.2 ± 1.6 recruits tile-1). Juvenile coral colony density was significantly lower on macroalgal-dominated reefs (2.4 ± 1.1 colonies m-2), compared to coral-dominated reefs (16.8 ± 2.4 m-2) and rubble-dominated reefs (33.1 ± 7.3 m-2), suggesting that macroalgal-dominated reefs have either a bottleneck to successful settlement on the natural substrates or a high post-settlement mortality bottleneck. Rubble-dominated reefs had very low cover of adult corals (10.0 ± 1.7 %) compared to coral-dominated reefs (33.4 ± 3.6 %) despite no statistical difference in their juvenile coral densities. A bottleneck caused by low juvenile colony survivorship on unconsolidated rubble-dominated reefs is possible, or alternatively, recruitment to rubble-dominated reefs has only recently begun. This

  7. A theory of traffic congestion at moving bottlenecks

    Science.gov (United States)

    Kerner, Boris S.; Klenov, Sergey L.

    2010-10-01

    The physics of traffic congestion occurring at a moving bottleneck on a multi-lane road is revealed based on the numerical analyses of vehicular traffic with a discrete stochastic traffic flow model in the framework of three-phase traffic theory. We find that there is a critical speed of a moving bottleneck at which traffic breakdown, i.e. a first-order phase transition from free flow to synchronized flow, occurs spontaneously at the moving bottleneck, if the flow rate upstream of the bottleneck is great enough. The greater the flow rate, the higher the critical speed of the moving bottleneck. A diagram of congested traffic patterns at the moving bottleneck is found, which shows regions in the flow-rate-moving-bottleneck-speed plane in which congested patterns emerge spontaneously or can be induced through large enough disturbances in an initial free flow. A comparison of features of traffic breakdown and resulting congested patterns at the moving bottleneck with known ones at an on-ramp (and other motionless) bottleneck is made. Nonlinear features of complex interactions and transformations of congested traffic patterns occurring at on- and off-ramp bottlenecks due to the existence of the moving bottleneck are found. The physics of the phenomenon of traffic congestion due to 'elephant racing' on a multi-lane road is revealed.

  8. A theory of traffic congestion at moving bottlenecks

    International Nuclear Information System (INIS)

    The physics of traffic congestion occurring at a moving bottleneck on a multi-lane road is revealed based on the numerical analyses of vehicular traffic with a discrete stochastic traffic flow model in the framework of three-phase traffic theory. We find that there is a critical speed of a moving bottleneck at which traffic breakdown, i.e. a first-order phase transition from free flow to synchronized flow, occurs spontaneously at the moving bottleneck, if the flow rate upstream of the bottleneck is great enough. The greater the flow rate, the higher the critical speed of the moving bottleneck. A diagram of congested traffic patterns at the moving bottleneck is found, which shows regions in the flow-rate-moving-bottleneck-speed plane in which congested patterns emerge spontaneously or can be induced through large enough disturbances in an initial free flow. A comparison of features of traffic breakdown and resulting congested patterns at the moving bottleneck with known ones at an on-ramp (and other motionless) bottleneck is made. Nonlinear features of complex interactions and transformations of congested traffic patterns occurring at on- and off-ramp bottlenecks due to the existence of the moving bottleneck are found. The physics of the phenomenon of traffic congestion due to 'elephant racing' on a multi-lane road is revealed.

  9. Analysis of bottleneck motion using Voronoi diagrams

    CERN Document Server

    Liddle, Jack; Steffen, Bernhard

    2010-01-01

    Standard definitions of the density exhibit large fluctuations when the size of the measurement area is comparable with the size of a pedestrian. An alternative measurement method exists where a personal space, calculated through the Voronoi diagram, is assigned to each pedestrian. In this contribution this method is applied to an experiment studying motion through a bottleneck and the reduced fluctuations demonstrated. The integrated density also permits examination on much smaller spatial scales than the standard definition, the insights into the pedestrian motion this provides are discussed.

  10. Where do they come from? Flow connectivity detects landscape bottlenecks

    OpenAIRE

    Alessandro Ferrarini

    2015-01-01

    In this paper, bottleneck flow connectivity is first introduced. A landscape bottleneck is defined here as the portion of an arbitrary study area which inevitably tunnels a specimen towards the point where it has been detected in situ. In other words, a bottleneck delimits the portion of the study area which forces the specimen to pass through the detected point of presence with, at most, a tolerance distance equal to an a priori defined uncertainty. There is one precise reason for the introd...

  11. Modified bottleneck-based heuristic for large-scale job-shop scheduling problems with a single bottleneck

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A modified bottleneck-based (MB) heuristic for large-scale job-shop scheduling problems with a welldefined bottleneck is suggested,which is simpler but more tailored than the shifting bottleneck (SB) procedure.In this algorithm,the bottleneck is first scheduled optimally while the non-bottleneck machines are subordinated around the solutions of the bottleneck schedule by some effective dispatching rules.Computational results indicate that the MB heuristic can achieve a better tradeoff between solution quality and computational time compared to SB procedure for medium-size problems.Furthermore,it can obtain a good solution in a short time for large-scale job-shop scheduling problems.

  12. Bimodal mesoporous silica with bottleneck pores.

    Science.gov (United States)

    Reber, M J; Brühwiler, D

    2015-11-01

    Bimodal mesoporous silica consisting of two sets of well-defined mesopores is synthesized by a partial pseudomorphic transformation of an ordered mesoporous starting material (SBA-15 type). The introduction of a second set of smaller mesopores (MCM-41 type) establishes a pore system with bottlenecks that restricts the access to the core of the bimodal mesoporous silica particles. The particle size and shape of the starting material are retained, but micropores present in the starting material disappear during the transformation, leading to a true bimodal mesoporous product. A varying degree of transformation allows the adjustment of the pore volume contribution of the two mesopore domains. Information on the accessibility of the mesopores is obtained by the adsorption of fluorescence-labeled poly(amidoamine) dendrimers and imaging by confocal laser scanning microscopy. This information is correlated with nitrogen sorption data to provide insights regarding the spatial distribution of the two mesopore domains. The bimodal mesoporous materials are excellent model systems for the investigation of cavitation effects in nitrogen desorption isotherms. PMID:26399172

  13. Bottleneck Management in Discrete Batch Production

    Directory of Open Access Journals (Sweden)

    Ferenčíková Denisa

    2012-06-01

    Full Text Available Today, production planning and scheduling becomes very important part of production management because companies have to react to dynamic market conditions and rising customers´ requirements for shorter delivery times, lower prices and better quality and services. They can use a lot of sophisticated methods and approaches to make their planning processes more efficient and thus meet growing customers´ requirements. However, using these new approaches is not so easy in all types of production systems. This paper deals with production planning and scheduling in discrete batch production that is just an example of very complicated production system. This type of production process is susceptible to demand fluctuation and facility exceptions and this implies bottleneck shifting. Therefore it is quite difficult to implement methods such as Theory of Constraints (TOC for production planning improvement in the standard way. One part of this paper is a case study wherecurrent production planning and scheduling in real factory is improved just through the use TOC principles.

  14. A theory of traffic congestion at heavy bottlenecks

    International Nuclear Information System (INIS)

    Spatiotemporal features and physics of vehicular traffic congestion occurring due to heavy highway bottlenecks caused for example by bad weather conditions or accidents are found based on simulations in the framework of three-phase traffic theory. A model of a heavy bottleneck is presented. Under a continuous non-limited increase in bottleneck strength, i.e., when the average flow rate within a congested pattern allowed by the heavy bottleneck decreases continuously up to zero, the evolution of the traffic phases in congested traffic, synchronized flow and wide moving jams, is studied. It is found that at a small enough flow rate within the congested pattern, the pattern exhibits a non-regular structure: a pinch region of synchronized flow within the pattern disappears and appears randomly over time; wide moving jams upstream of the pinch region exhibit a complex non-regular dynamics in which the jams appear and disappear randomly. At greater bottleneck strengths, wide moving jams merge onto a mega-wide moving jam (mega-jam) within which low-speed patterns with a complex non-regular spatiotemporal dynamics occur. We show that when the bottleneck strength is great enough, only the mega-jam survives and synchronized flow remains only within its downstream front separating free flow and congested traffic. Theoretical results presented can explain why no sequence of wide moving jams can often be distinguished in non-homogeneous traffic congestion measured at very heavy bottlenecks caused by bad weather conditions or accidents

  15. Deep bottleneck features for spoken language identification.

    Directory of Open Access Journals (Sweden)

    Bing Jiang

    Full Text Available A key problem in spoken language identification (LID is to design effective representations which are specific to language information. For example, in recent years, representations based on both phonotactic and acoustic features have proven their effectiveness for LID. Although advances in machine learning have led to significant improvements, LID performance is still lacking, especially for short duration speech utterances. With the hypothesis that language information is weak and represented only latently in speech, and is largely dependent on the statistical properties of the speech content, existing representations may be insufficient. Furthermore they may be susceptible to the variations caused by different speakers, specific content of the speech segments, and background noise. To address this, we propose using Deep Bottleneck Features (DBF for spoken LID, motivated by the success of Deep Neural Networks (DNN in speech recognition. We show that DBFs can form a low-dimensional compact representation of the original inputs with a powerful descriptive and discriminative capability. To evaluate the effectiveness of this, we design two acoustic models, termed DBF-TV and parallel DBF-TV (PDBF-TV, using a DBF based i-vector representation for each speech utterance. Results on NIST language recognition evaluation 2009 (LRE09 show significant improvements over state-of-the-art systems. By fusing the output of phonotactic and acoustic approaches, we achieve an EER of 1.08%, 1.89% and 7.01% for 30 s, 10 s and 3 s test utterances respectively. Furthermore, various DBF configurations have been extensively evaluated, and an optimal system proposed.

  16. Impacts of genetic bottlenecks on soybean genome diversity

    OpenAIRE

    Hyten, David L; Song, Qijian; Zhu, Youlin; Choi, Ik-Young; Nelson, Randall L.; Costa, Jose M.; Specht, James E; Shoemaker, Randy C.; Cregan, Perry B

    2006-01-01

    Soybean has undergone several genetic bottlenecks. These include domestication in Asia to produce numerous Asian landraces, introduction of relatively few landraces to North America, and then selective breeding over the past 75 years. It is presumed that these three human-mediated events have reduced genetic diversity. We sequenced 111 fragments from 102 genes in four soybean populations representing the populations before and after genetic bottlenecks. We show that soybean has lost many rare...

  17. Bottleneck management in the German and European electricity supply

    International Nuclear Information System (INIS)

    This publication describes how bottlenecks in the German and European electricity supply pose a danger to the realization of the European internal market in electricity, the transition to electricity production from renewable resources and to the safeguarding of grid availability and security of supply. Bottlenecks at cross-border interconnectors between member states of the European Union are hampering cross-border trade in electricity, posing an impediment to EU-wide competition among electricity production and electricity trading companies. Grid bottlenecks at cross-border interconnectors isolate national markets from one another, with the result that it is not always possible in the European Union to have the most competitive power plant produce electricity. This amounts to a loss of welfare compared with what it would be in the case of an electricity supply without bottlenecks. Furthermore, bottlenecks make it impossible for green electricity that would be eligible for promotion for reasons of climate and environmental protection to be transmitted unimpeded from the most suitable site to the consumer regions. Thus the transmission of electricity produced from wind power in Northern Germany to the industrial centres in Southern Germany is impeded by bottlenecks along the north-south lines of the national transmission network. Today some of the German electricity supply networks already have to be operated near the limits of their capacity, especially during high wind episodes. This poses a growing danger to network availability and security of supply. Since the installation, expansion and conversion of electricity supply networks in Germany and other member states of the European Union is no longer progressing at the required speed, growing importance attaches to the management of bottlenecks. The goal of bottleneck management is to resolve conflicts over network use such as can occur in overload situations with as little discrimination and as little

  18. Where do they come from? Flow connectivity detects landscape bottlenecks

    Directory of Open Access Journals (Sweden)

    Alessandro Ferrarini

    2015-03-01

    Full Text Available In this paper, bottleneck flow connectivity is first introduced. A landscape bottleneck is defined here as the portion of an arbitrary study area which inevitably tunnels a specimen towards the point where it has been detected in situ. In other words, a bottleneck delimits the portion of the study area which forces the specimen to pass through the detected point of presence with, at most, a tolerance distance equal to an a priori defined uncertainty. There is one precise reason for the introduction of bottleneck flow connectivity: when a specimen is detected through in situ observations or GPS devices, it should be possible to derive the portion of the landscape where it can come from. In fact, the detected specimen is usually just one individual of an entire population that is moving somewhere in the landscape. Hence, such specimen can work as a tracker of the whole population if we have the proper methodological tools to turn its detected position into a map where the landscape bottleneck of the detected location is delineated. In case of a species of conservation interest, the application of bottleneck flow connectivity is useful for the individuation and then the conservation of such population. In case of an exotic undesired species, bottleneck flow connectivity can help individuate the location of the population that should be eradicated, starting from few field observations. An applicative example for wolf in the Ceno Valley (Italy is provided. Bottleneck flow connectivity has thus interesting implications both for the conservation of species of interest, but also for the management of undesired exotic species.

  19. Optimizing Database Architecture for the New Bottleneck: Memory Access

    OpenAIRE

    Manegold, Stefan; Boncz, Peter; Kersten, Martin

    2000-01-01

    In the past decade, advances in speed of commodity CPUs have far out-paced advances in memory latency. Main-memory access is therefore increasingly a performance bottleneck for many computer applications, including database systems. In this article, we use a simple scan test to show the severe impact of this bottleneck. The insights gained are translated into guidelines for database architecture; in terms of both data structures and algorithms. We discuss how vertically fragmented data struct...

  20. Database architecture optimized for the new bottleneck: Memory access

    OpenAIRE

    Boncz, Peter; Manegold, Stefan; Kersten, Martin

    1999-01-01

    In the past decade, advances in speed of commodity CPUs have far out-paced advances in memory latency. Main-memory access is therefore increasingly a performance bottleneck for many computer applications, including database systems. In this article, we use a simple scan test to show the severe impact of this bottleneck. The insights gained are translated into guidelines for database architecture; in terms of both data structures and algorithms. We discuss how vertically fragmented data struct...

  1. Steady State of Pedestrian Flow in Bottleneck Experiments

    CERN Document Server

    Liao, Weichen; Seyfried, Armin; Chraibi, Mohcine; Drzycimski, Kevin; Zheng, Xiaoping; Zhao, Ying

    2015-01-01

    Experiments with pedestrians could depend strongly on initial conditions. Comparisons of the results of such experiments require to distinguish carefully between transient state and steady state. In this work, a feasible algorithm - Cumulative Sum Control Chart - is proposed and improved to automatically detect steady states from density and speed time series of bottleneck experiments. The threshold of the detection parameter in the algorithm is calibrated using an autoregressive model. Comparing the detected steady states with previous manually selected ones, the modified algorithm gives more reproducible results. For the applications, three groups of bottleneck experiments are analysed and the steady states are detected. The study about pedestrian flow shows that the difference between the flows in all states and in steady state mainly depends on the ratio of pedestrian number to bottleneck width. When the ratio is higher than a critical value (approximately 115 persons/m), the flow in all states is almost ...

  2. Research of Cruise Industry Development Bottlenecks In China

    Directory of Open Access Journals (Sweden)

    Ping Zhou

    2014-08-01

    Full Text Available Cruise industry is a comprehensive new industry, which has a strong impetus to the development of other industries. In recent years, as the explosive growth in cruise market, China has become a global rapidly-growing emerging cruise market. The cruise industry has begun transiting from infancy to the development phase, in all likelihood facing a number of bottlenecks problem. In this paper, the development trend of the cruise industry is first analyzed, then the bottlenecks of cruise industry are studied and finally some reasonable countermeasures and suggestions are put forward. By perfecting policy and legal, expanding industrial chain, diversifying investment mode, cultivating the market of consumer subjects, and establishing a scientific talents training mode of enterprise, the bottlenecks of cruise industry can be solved. This will consequently promote healthy and rapid development in cruise tourism industry, and give full play to the role of joint economy.

  3. Bottleneck Paths and Trees and Deterministic Graphical Games

    OpenAIRE

    Chechik, Shiri; Kaplan, Haim; Thorup, Mikkel; Zamir, Or; Zwick, Uri

    2016-01-01

    Gabow and Tarjan showed that the Bottleneck Path (BP) problem, i.e., finding a path between a given source and a given target in a weighted directed graph whose largest edge weight is minimized, as well as the Bottleneck spanning tree (BST) problem, i.e., finding a directed spanning tree rooted at a given vertex whose largest edge weight is minimized, can both be solved deterministically in O(m * log^*(n)) time, where m is the number of edges and n is the number of vertices in the graph. We p...

  4. The "Bottleneck" Behaviours in Linear FNNCs and Their Breakthrough

    Institute of Scientific and Technical Information of China (English)

    HUANG Deshuang

    1999-01-01

    The classification mechanisms of linear feed forward neural network classifiers (FNNC), whose hidden layer performs the Fisher lineartrans formation of the input patterns, under the supervision of outer-supervised signals are investigated. The "bottleneck" behavioursin linear FNNCs are observed and analyzed. In addition, the structure stabilities of the linear FNNCs are also discussed. It is pointed out that the key point to break through the "bottleneck" behaviours forlinear FNNCs is to change linear hidden neurons into nonlinear hiddenones. Finally, the experimental results, taking the parity 3 problem asexample, are given.

  5. Fast Approximation Algorithm for Restricted Euclidean Bottleneck Steiner Tree Problem

    Directory of Open Access Journals (Sweden)

    Zimao Li

    2014-04-01

    Full Text Available Bottleneck Steiner tree problem asks to find a Steiner tree for n terminals with at most k Steiner points such that the length of the longest edge in the tree is minimized. The problem has applications in the design of wireless communication networks. In this paper we study a restricted version of the bottleneck Steiner tree problem in the Euclidean plane which requires that only degree-2 Steiner points are possibly adjacent in the optimal solution. We first show that the problem is NP-hard and cannot be approximated within unless P=NP, and provide a fast polynomial time deterministic approximation algorithm with performance ratio .

  6. The Case for a Gaian Bottleneck: The Biology of Habitability.

    Science.gov (United States)

    Chopra, Aditya; Lineweaver, Charles H

    2016-01-01

    The prerequisites and ingredients for life seem to be abundantly available in the Universe. However, the Universe does not seem to be teeming with life. The most common explanation for this is a low probability for the emergence of life (an emergence bottleneck), notionally due to the intricacies of the molecular recipe. Here, we present an alternative Gaian bottleneck explanation: If life emerges on a planet, it only rarely evolves quickly enough to regulate greenhouse gases and albedo, thereby maintaining surface temperatures compatible with liquid water and habitability. Such a Gaian bottleneck suggests that (i) extinction is the cosmic default for most life that has ever emerged on the surfaces of wet rocky planets in the Universe and (ii) rocky planets need to be inhabited to remain habitable. In the Gaian bottleneck model, the maintenance of planetary habitability is a property more associated with an unusually rapid evolution of biological regulation of surface volatiles than with the luminosity and distance to the host star. PMID:26789354

  7. The bottleneck may be the solution, not the problem.

    Science.gov (United States)

    Lotem, Arnon; Kolodny, Oren; Halpern, Joseph Y; Onnis, Luca; Edelman, Shimon

    2016-01-01

    As a highly consequential biological trait, a memory "bottleneck" cannot escape selection pressures. It must therefore co-evolve with other cognitive mechanisms rather than act as an independent constraint. Recent theory and an implemented model of language acquisition suggest that a limit on working memory may evolve to help learning. Furthermore, it need not hamper the use of language for communication. PMID:27562516

  8. Towards a microscopic understanding of the phonon bottleneck

    Science.gov (United States)

    Garanin, D. A.

    2007-03-01

    The problem of the phonon bottleneck in the relaxation of two-level systems (spins) to a narrow group of resonant phonons via emission-absorption processes is investigated from first principles. It is shown that the kinetic approach based on the Pauli master equation is invalid because of the narrow distribution of the phonons exchanging their energy with the spins. This results in a long-memory effect that can be best taken into account by introducing an additional dynamical variable corresponding to the nondiagonal matrix elements responsible for spin-phonon correlation. The resulting system of dynamical equations describes the phonon-bottleneck plateau in the spin excitation, as well as a gap in the spin-phonon spectrum, for any finite concentration of spins. On the other hand, it does not accurately render the line shape of emitted phonons and still needs improving.

  9. Nearly Optimal Solution for Restricted Euclidean Bottleneck Steiner Tree Problem

    Directory of Open Access Journals (Sweden)

    Zimao Li

    2014-04-01

    Full Text Available A variation of the traditional Steiner tree problem, the bottleneck Steiner tree problem is considered in this paper, which asks to find a Steiner tree for n terminals with at most k Steiner points such that the length of the longest edge in the tree is minimized. The problem has applications in the design of WDM optical networks, design of wireless communication networks and reconstruction of phylogenetic tree in biology. We study a restricted version of the bottleneck Steiner tree problem in the Euclidean plane which requires that only degree-2 Steiner points are possibly adjacent in the optimal solution. The problem is known to be MAX-SNP hard and cannot be approximated within unless P=NP, we propose a nearly optimal randomized polynomial time approximation algorithm with performance ratio +e, where e is a positive number.

  10. Bottleneck Non-Crossing Matching in the Plane

    CERN Document Server

    Abu-Affash, A Karim; Katz, Matthew J; Trabelsi, Yohai

    2012-01-01

    Let $P$ be a set of $2n$ points in the plane, and let $M_{\\rm C}$ (resp., $M_{\\rm NC}$) denote a bottleneck matching (resp., a bottleneck non-crossing matching) of $P$. We study the problem of computing $M_{\\rm NC}$. We first prove that the problem is NP-hard and does not admit a PTAS. Then, we present an $O(n^{1.5}\\log^{0.5} n)$-time algorithm that computes a non-crossing matching $M$ of $P$, such that $bn(M) \\le 2\\sqrt{10} \\cdot bn(M_{\\rm NC})$, where $bn(M)$ is the length of a longest edge in $M$. An interesting implication of our construction is that $bn(M_{\\rm NC})/bn(M_{\\rm C}) \\le 2\\sqrt{10}$.

  11. Energetic bottlenecks and other design constraints in avian annual cycles

    OpenAIRE

    Piersma, T

    2002-01-01

    The flexible phenotypes of birds and mammals often appear to represent adjustments to alleviate some energetic bottleneck or another. By increasing the size of the organs involved in digestion and assimilation of nutrients (gut and liver), an individual bird can increase its ability to process nutrients, for example to quickly store fuel for onward flight. Similarly, an increase in the exercise organs (pectoral muscles and heart) enables a bird to increase its metabolic power for sustained fl...

  12. Health Care Reform and the Primary Care Workforce Bottleneck

    OpenAIRE

    Schwartz, Mark D

    2011-01-01

    To establish and sustain the high-performing health care system envisioned in the Affordable Care Act (ACA), current provisions in the law to strengthen the primary care workforce must be funded, implemented, and tested. However, the United States is heading towards a severe primary care workforce bottleneck due to ballooning demand and vanishing supply. Demand will be fueled by the “silver tsunami” of 80 million Americans retiring over the next 20 years and the expanded insurance coverage fo...

  13. Metaheuristic procedures for the lexicographic bottleneck assembly line balancing problem

    OpenAIRE

    Pastor Moreno, Rafael; García Villoria, Alberto; Laguna, Manuel; Martí Cunquero, Rafael

    2015-01-01

    The goal of this work is to develop an improved procedure for the solution of the lexicographic bottleneck variant of the assembly line balancing problem (LB-ALBP). The objective of the LB-ALBP is to minimize the workload of the most heavily loaded workstation, followed by the workload of the second most heavily loaded workstation and so on. This problem-recently introduced to the literature (Pastor, 2011)-has practical relevance to manufacturing facilities. We design, implement and fine-tune...

  14. Congestion costs in bottleneck equilibrium with stochastic capacity and demand

    OpenAIRE

    Fosgerau, Mogens

    2008-01-01

    I analyse congestion costs in the Vickrey bottleneck model of a congestible facility with a peak load in demand. The shape of the peak is endogenous, being the sum of individual scheduling decisions. Capacity and demand are random, which introduces uncertainty into the individual scheduling choices. These are essential features of actual peak loads. Based on work by Arnott, de Palma and Lindsey, I derive the expected marginal and total congestion costs and compare to the case with fixed capac...

  15. Linguistics, cognitive psychology, and the Now-or-Never bottleneck.

    Science.gov (United States)

    Endress, Ansgar D; Katzir, Roni

    2016-01-01

    Christiansen & Chater (C&C)'s key premise is that "if linguistic information is not processed rapidly, that information is lost for good" (sect. 1, para. 1). From this "Now-or-Never bottleneck" (NNB), C&C derive "wide-reaching and fundamental implications for language processing, acquisition and change as well as for the structure of language itself" (sect. 2, para. 10). We question both the premise and the consequentiality of its purported implications. PMID:27561603

  16. Bottleneck on Supply Chain of Organic Agricultural Products and Countermeasures

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin-min

    2012-01-01

    Organic agriculture is one of successful models of low-carbon agriculture, and plays an important role in alleviating and adapting to climate change. However, the development of supply chain of organic agricultural products lags behind, which seriously restricts development of organic agricultural product market. In this paper, major models and bottleneck of supply chain of organic agricultural products are analyzed, and finally countermeasures are put forward.

  17. Time minimizing transportation problem with fractional bottleneck objective function

    OpenAIRE

    Jain Madhuri; Saksena P.K.

    2012-01-01

    This paper is aimed at studying the Time Minimizing Transportation Problem with Fractional Bottleneck Objective Function (TMTP-FBOF). TMTP-FBOF is related to a Lexicographic Fractional Time Minimizing Transportation Problem (LFTMTP), which will be solved by a lexicographic primal code. An algorithm is also developed to determine an initial efficient basic solution to this TMTP-FBOF. The developed TMTP-FBOF Algorithm is supported by a real life example of Military Transportation Problem ...

  18. Restricted Dynamic Programming Heuristic for Precedence Constrained Bottleneck Generalized TSP

    OpenAIRE

    Salii, Y.

    2015-01-01

    We develop a restricted dynamical programming heuristic for a complicated traveling salesman problem: a) cities are grouped into clusters, resp. Generalized TSP; b) precedence constraints are imposed on the order of visiting the clusters, resp. Precedence Constrained TSP; c) the costs of moving to the next cluster and doing the required job inside one are aggregated in a minimax manner, resp. Bottleneck TSP; d) all the costs may depend on the sequence of previously visited clusters, resp. Seq...

  19. Clogging transition of many-particle systems flowing through bottlenecks

    OpenAIRE

    Iker Zuriguel; Daniel Ricardo Parisi; Raúl Cruz Hidalgo; Celia Lozano; Alvaro Janda; Paula Alejandra Gago; Juan Pablo Peralta; Luis Miguel Ferrer; Luis Ariel Pugnaloni; Eric Clément; Diego Maza; Ignacio Pagonabarraga; Angel Garcimartín

    2014-01-01

    When a large set of discrete bodies passes through a bottleneck, the flow may become intermittent due to the development of clogs that obstruct the constriction. Clogging is observed, for instance, in colloidal suspensions, granular materials and crowd swarming, where consequences may be dramatic. Despite its ubiquity, a general framework embracing research in such a wide variety of scenarios is still lacking. We show that in systems of very different nature and scale -including sheep herds, ...

  20. The bottleneck effect in three-dimensional turbulence simulations

    CERN Document Server

    Dobler, W; Yousef, T A; Brandenburg, A; Dobler, Wolfgang; Haugen, Nils Erland L.; Yousef, Tarek A.; Brandenburg, Axel

    2003-01-01

    At numerical resolutions around $512^3$ and above, three-dimensional energy spectra from turbulence simulations begin to show noticeably shallower spectra than $k^{-5/3}$ near the Kolmogorov dissipation wavenumber (`bottleneck effect'). This effect is shown to be significantly weaker in one-dimensional spectra like those obtained in wind tunnel turbulence. The difference can be understood in terms of the transformation between one-dimensional and three-dimensional energy spectra under the assumption that the turbulent velocity field is isotropic. Transversal and longitudinal energy spectra are similar and can both accurately be computed from the full three-dimensional spectra.

  1. A lexisearch Algorithm for the Bottleneck Traveling Salesman Problem

    Directory of Open Access Journals (Sweden)

    Zakir H. Ahmed

    2010-02-01

    Full Text Available The Bottleneck Traveling Salesman Problem (BTSP is a variation of the well-known Traveling Salesman Problem in which the objective is to minimize the maximum lap (arc length in the tour of the salesman. In this paper, a lexisearch algorithm using adjacency representation for a tour has been developed for obtaining exact optimal solution to the problem. Then a comparative study has been carried out to show the efficiency of the algorithm as against existing exact algorithm for some randomly generated and TSPLIB instances of different sizes.

  2. Give or take? Rewards vs. Charges for a Congested Bottleneck

    OpenAIRE

    Rouwendal, Jan; Erik T. Verhoef; Knockaert, Jasper

    2010-01-01

    This discussion paper resulted in a publication in 'Regional Science and Urban Economics', 42(1-2), 166-76.This paper analyzes the possibilities to relieve congestion using rewards instead of taxes, as well as combinations of rewards and taxes. The model considers a Vickrey-ADL model of bottleneck congestion with endogenous scheduling. With inelastic demand, a fine (time-varying) reward is equivalent to a fine toll, and to a continuum of combinations of time-varying tolls and rewards (includi...

  3. Bottlenecks in molecular testing for rare genetic diseases.

    Science.gov (United States)

    Willems, Patrick J

    2008-06-01

    Despite the impressive progress in our understanding of the genetic causes of genetic diseases over the past decade, molecular diagnosis for rare genetic disorders is still in its infancy, being slow, expensive, unreliable, insufficient, and ill-organized in many countries. This leaves the gap between the hype of the current genomic research and the hope for a simple genetic diagnosis too large for patients and families affected with genetic disease. The bottlenecks in the molecular testing for rare genetic disorders are discussed below. PMID:18412107

  4. Orphan drug development across Europe: bottlenecks and opportunities.

    Science.gov (United States)

    Heemstra, Harald E; de Vrueh, Remco L A; van Weely, Sonja; Büller, Hans A; Leufkens, Hubert G M

    2008-08-01

    With the assignment of the 500th European Union orphan drug designation in 2007, the Regulation on Orphan Medicinal Products truly begins to show its potential for delivering new medicines to patients with rare diseases. Here, we analysed European orphan drug development at a national level and unveil a strong relationship between orphan drug development and pharmaceutical innovation performance in Europe. Moreover, we identify gaps in transition from science into orphan drug development as important bottlenecks that exist in several European countries. Our findings underline the importance of innovation-based policies to enhance the development of orphan drugs in Europe. PMID:18583178

  5. Asymmetric exclusion processes on a closed network with bottlenecks

    International Nuclear Information System (INIS)

    We study the generic nonequilibrium steady states in asymmetric exclusion processes on a closed network with bottlenecks. To this end we propose and study closed simple networks with multiple-connected non-identical junctions. Depending upon the parameters that define the network junctions and the particle number density, the models display phase transitions with both static and moving density inhomogeneities. The currents in the models can be tuned by the junction parameters. Our models highlight how extended and point defects may affect the density profiles in a closed directed network. Phenomenological implications of our results are discussed. (paper)

  6. A bottleneck model of set-specific capture.

    Directory of Open Access Journals (Sweden)

    Katherine Sledge Moore

    Full Text Available Set-specific contingent attentional capture is a particularly strong form of capture that occurs when multiple attentional sets guide visual search (e.g., "search for green letters" and "search for orange letters". In this type of capture, a potential target that matches one attentional set (e.g. a green stimulus impairs the ability to identify a temporally proximal target that matches another attentional set (e.g. an orange stimulus. In the present study, we investigated whether set-specific capture stems from a bottleneck in working memory or from a depletion of limited resources that are distributed across multiple attentional sets. In each trial, participants searched a rapid serial visual presentation (RSVP stream for up to three target letters (T1-T3 that could appear in any of three target colors (orange, green, or lavender. The most revealing findings came from trials in which T1 and T2 matched different attentional sets and were both identified. In these trials, T3 accuracy was lower when it did not match T1's set than when it did match, but only when participants failed to identify T2. These findings support a bottleneck model of set-specific capture in which a limited-capacity mechanism in working memory enhances only one attentional set at a time, rather than a resource model in which processing capacity is simultaneously distributed across multiple attentional sets.

  7. A methodology for determining and controlling the buffers before floating bottlenecks in heavy machinery production

    Directory of Open Access Journals (Sweden)

    R. Lenort

    2013-07-01

    Full Text Available Heavy machinery industry is characterized by a number of specific features that cause significant variations in the processing time of products in the individual workplaces and frequent occurrence of floating bottlenecks, which change their positions. Depending on the product range being processed, a given workplace is the bottleneck only for some period of time. When the bottleneck moves to another workplace, it leads to unnecessary loss of capacity of the floating bottleneck. To maximize the utilization, it is necessary to protect those bottlenecks by creating special buffers. The objective of this article is to design a methodology used for the determination and control of buffers that are going to protect the floating bottlenecks from operating capacity losses caused by transfer of the constrain to another workplace. These buffers are referred to as „power buffers“. The designed methodology has been verified in the process of forged pieces machining.

  8. Size of genetic bottlenecks leading to virus fitness loss is determined by mean initial population fitness.

    OpenAIRE

    Novella, I S; Elena, S F; Moya, A.; Domingo, E; Holland, J J

    1995-01-01

    Genetic bottlenecks are important events in the genetic diversification of organisms and colonization of new ecological niches. Repeated bottlenecking of RNA viruses often leads to fitness losses due to the operation of Muller's ratchet. Herein we use vesicular stomatitis virus to determine the transmission population size which leads to fitness decreases of virus populations. Remarkably, the effective size of a genetic bottleneck associated with fitness loss is greater when the fitness of th...

  9. Client-server computer architecture saves costs and eliminates bottlenecks

    International Nuclear Information System (INIS)

    This paper reports that workstation, client-server architecture saved costs and eliminated bottlenecks that BP Exploration (Alaska) Inc. experienced with mainframe computer systems. In 1991, BP embarked on an ambitious project to change technical computing for its Prudhoe Bay, Endicott, and Kuparuk operations on Alaska's North Slope. This project promised substantial rewards, but also involved considerable risk. The project plan called for reservoir simulations (which historically had run on a Cray Research Inc. X-MP supercomputer in the company's Houston data center) to be run on small computer workstations. Additionally, large Prudhoe Bay, Endicott, and Kuparuk production and reservoir engineering data bases and related applications also would be moved to workstations, replacing a Digital Equipment Corp. VAX cluster in Anchorage

  10. Queuing model of a traffic bottleneck with bimodal arrival rate

    Science.gov (United States)

    Woelki, Marko

    2016-06-01

    This paper revisits the problem of tuning the density in a traffic bottleneck by reduction of the arrival rate when the queue length exceeds a certain threshold, studied recently for variants of totally asymmetric simple exclusion process (TASEP) and Burgers equation. In the present approach, a simple finite queuing system is considered and its contrasting “phase diagram” is derived. One can observe one jammed region, one low-density region and one region where the queue length is equilibrated around the threshold. Despite the simplicity of the model the physics is in accordance with the previous approach: The density is tuned at the threshold if the exit rate lies in between the two arrival rates.

  11. Traffic Flow States in a Freeway with Bottleneck

    Institute of Scientific and Technical Information of China (English)

    PENG Zi-Hui; SUN Gang; ZHU Jing-Yi

    2009-01-01

    The system of mixture of single lane and double lane is studied by a cellular automata model, which is developed by us based on the Nagel and Schreckenberg's models. We justify that the model can reach a stable states quickly. The density distributions of the stable state is presented for several cases, which illustrate the manner of the congestion. The relationship between the outflow rate and the total number of vehicles and that between the outflow rate and the density just before the bottleneck are both given. Comparing with the relationship that occurring in the granular flow, we conclude that the transition from the free traffic flow to the congested traffic flow can also be attributed to the abrupt variation through unstable flow state, which can naturally explain the discontinuities and the complex time variation behavior observed in the traffic flow experiments.

  12. Breaking the biomass bottleneck of the fossil free society

    DEFF Research Database (Denmark)

    Wenzel, Henrik

    for heat and power services as well as for transportation fuels and as feedstock for chemicals and materials – i.e. in practice all sectors today being dependant on fossil fuels. At the same time, unfortunately, the food sector is also in growing demand for agricultural crops. World population is still...... demand on food prices, namely the food crisis in 2007 – 2008. During this period, market prices on food and feed crops increased by almost a factor of 2, and the part of the world population suffering from hunger and starvation increased from 800 million to 900 million people. The amount of biomass...... resources, the food sector and the poorest part of the world population. We can, however, break this bottleneck. First of all, we must seek further energy savings. Secondly, we need to look for ways to de-carbonize society. There is a growing consensus among energy scientists and energy planners...

  13. Genetic diversity and bottleneck studies in the Marwari horse breed

    Indian Academy of Sciences (India)

    A. K. Gupta; M. Chauhan; S. N. Tandon; Sonia

    2005-12-01

    Genetic diversity within the Marwari breed of horses was evaluated using 26 different microsatellite pairs with 48 DNA samples from unrelated horses. This molecular characterisation was undertaken to evaluate the problem of genetic bottlenecks also, if any, in this breed. The estimated mean (± s.e.) allelic diversity was 5.9 (± 2.24), with a total of 133 alleles. A high level of genetic variability within this breed was observed in terms of high values of mean (± s.e.) effective number of alleles (3.3 ± 1.27), observed heterozygosity (0.5306 ± 0.22), expected Levene’s heterozygosity (0.6612 ± 0.15), expected Nei’s heterozygosity (0.6535 ± 0.14), and polymorphism information content (0.6120 ± 0.03). Low values of Wright’s fixation index, $F_{\\text{IS}}$ (0.2433 ± 0.05) indicated low levels of inbreeding. This basic study indicated the existence of substantial genetic diversity in the Marwari horse population. No significant genotypic linkage disequilibrium was detected across the population, suggesting no evidence of linkage between loci. A normal ‘L’ shaped distribution of mode–shift test, non-significant heterozygote excess on the basis of different models, as revealed from Sign, Standardized differences and Wilcoxon sign rank tests as well as non-significant ratio value suggested that there was no recent bottleneck in the existing Marwari breed population, which is important information for equine breeders. This study also revealed that the Marwari breed can be differentiated from some other exotic breeds of horses on the basis of three microsatellite primers.

  14. Divergent evolution peaks under intermediate population bottlenecks during bacterial experimental evolution.

    Science.gov (United States)

    Vogwill, Tom; Phillips, Robyn L; Gifford, Danna R; MacLean, R Craig

    2016-07-27

    There is growing evidence that parallel molecular evolution is common, but its causes remain poorly understood. Demographic parameters such as population bottlenecks are predicted to be major determinants of parallelism. Here, we test the hypothesis that bottleneck intensity shapes parallel evolution by elucidating the genomic basis of adaptation to antibiotic-supplemented media in hundreds of populations of the bacterium Pseudomonas fluorescens Pf0-1. As expected, bottlenecking decreased the rate of phenotypic and molecular adaptation. Surprisingly, bottlenecking had no impact on the likelihood of parallel adaptive molecular evolution at a genome-wide scale. However, bottlenecking had a profound impact on the genes involved in antibiotic resistance. Specifically, under either intense or weak bottlenecking, resistance predominantly evolved by strongly beneficial mutations which provide high levels of antibiotic resistance. In contrast with intermediate bottlenecking regimes, resistance evolved by a greater diversity of genetic mechanisms, significantly reducing the observed levels of parallel genetic evolution. Our results demonstrate that population bottlenecking can be a major predictor of parallel evolution, but precisely how may be more complex than many simple theoretical predictions. PMID:27466449

  15. Bottlenecks of motion processing during a visual glance: the leaky flask model.

    Directory of Open Access Journals (Sweden)

    Haluk Öğmen

    Full Text Available Where do the bottlenecks for information and attention lie when our visual system processes incoming stimuli? The human visual system encodes the incoming stimulus and transfers its contents into three major memory systems with increasing time scales, viz., sensory (or iconic memory, visual short-term memory (VSTM, and long-term memory (LTM. It is commonly believed that the major bottleneck of information processing resides in VSTM. In contrast to this view, we show major bottlenecks for motion processing prior to VSTM. In the first experiment, we examined bottlenecks at the stimulus encoding stage through a partial-report technique by delivering the cue immediately at the end of the stimulus presentation. In the second experiment, we varied the cue delay to investigate sensory memory and VSTM. Performance decayed exponentially as a function of cue delay and we used the time-constant of the exponential-decay to demarcate sensory memory from VSTM. We then decomposed performance in terms of quality and quantity measures to analyze bottlenecks along these dimensions. In terms of the quality of information, two thirds to three quarters of the motion-processing bottleneck occurs in stimulus encoding rather than memory stages. In terms of the quantity of information, the motion-processing bottleneck is distributed, with the stimulus-encoding stage accounting for one third of the bottleneck. The bottleneck for the stimulus-encoding stage is dominated by the selection compared to the filtering function of attention. We also found that the filtering function of attention is operating mainly at the sensory memory stage in a specific manner, i.e., influencing only quantity and sparing quality. These results provide a novel and more complete understanding of information processing and storage bottlenecks for motion processing.

  16. Analysis of registered CDM projects: potential removal of evidenced bottlenecks

    Energy Technology Data Exchange (ETDEWEB)

    Agosto, D.; Bombard, P.; Gostinelli, F.

    2007-07-01

    The Clean Development Mechanism (CDM) has developed during its first period of implementation, a distinctive set of patterns. The authors thought of concentrating on the CDM analysis in order to highlight potential remedies or reasons for given bottlenecks. In order to establish a sort of extensive SWOT analysis for CDMs, all the 356 projects actually (November 2006) registered at UNFCCC were examined, together with all the about 1000 PDDs presented to the UNFCCC but not registered yet. The CDM projects have been studied trying to cluster projects according to relevant characteristics, both from a technical and an economic point of view. Chosen indicators are meant to identify: more convenient/more diffused energy system for a CDM; reasons for a geographical distribution of different types of projects; potentials for a future exploitation of lower used technologies in CDM. Conclusions are drawn and appropriate tables and graphs presented. (1) the Baseline Emission Factor, combined to economic patterns, is the pivotal factor that characterizes both choices of host country and technology; (2) some technologies can exploit appropriately CDM scheme, whilst other technologies, are constrained by it. (3) there are still some important weak points: grouping of non Annex I countries; crediting period; criteria for the evaluation of sustainable development. (auth)

  17. Narrower bottlenecks could be more efficient for concentrating choanoflagellates

    Science.gov (United States)

    Sparacino, J.; Miño, G.; Koehl, M. A. R.; King, N.; Stocker, R.; Banchio, A. J.; Marconi, V. I.

    2015-11-01

    In evolutionary biology choanoflagellates are broadly investigated as the closest living relatives of the animal ancestors. Under diverse environmental cues, choanoflagellate Salpingoeca rosetta can differentiate in two types of solitary swimming cells: slow and fast microswimmers. Here we present a first phenomenological 2D-model for the choanoflagellates dynamics confined into a flat device divided by a wall of asymmetric microconstrictions. The model allow us to optimize the geometry of the microchannels for directing and concentrating cell populations under strict control. We solve our set of dynamical equations using Langevin dynamics. Experimental parameters for the motility of the slow and fast cells were measured and used for our numerical estimations of the directed transport efficiency, otherwise we have no adjustable parameters. We find remarkable differences in the rectification results for slow and fast choanoflagellates, which give us a strategy to develop a suitable microfluidic sorting device. For a given population velocity, narrower bottlenecks, of similar size to the cell dimension, show to be more efficient as concentrator of populations. Experiments and simulations are in good agreement.

  18. Photonic ADC: overcoming the bottleneck of electronic jitter.

    Science.gov (United States)

    Khilo, Anatol; Spector, Steven J; Grein, Matthew E; Nejadmalayeri, Amir H; Holzwarth, Charles W; Sander, Michelle Y; Dahlem, Marcus S; Peng, Michael Y; Geis, Michael W; DiLello, Nicole A; Yoon, Jung U; Motamedi, Ali; Orcutt, Jason S; Wang, Jade P; Sorace-Agaskar, Cheryl M; Popović, Miloš A; Sun, Jie; Zhou, Gui-Rong; Byun, Hyunil; Chen, Jian; Hoyt, Judy L; Smith, Henry I; Ram, Rajeev J; Perrott, Michael; Lyszczarz, Theodore M; Ippen, Erich P; Kärtner, Franz X

    2012-02-13

    Accurate conversion of wideband multi-GHz analog signals into the digital domain has long been a target of analog-to-digital converter (ADC) developers, driven by applications in radar systems, software radio, medical imaging, and communication systems. Aperture jitter has been a major bottleneck on the way towards higher speeds and better accuracy. Photonic ADCs, which perform sampling using ultra-stable optical pulse trains generated by mode-locked lasers, have been investigated for many years as a promising approach to overcome the jitter problem and bring ADC performance to new levels. This work demonstrates that the photonic approach can deliver on its promise by digitizing a 41 GHz signal with 7.0 effective bits using a photonic ADC built from discrete components. This accuracy corresponds to a timing jitter of 15 fs - a 4-5 times improvement over the performance of the best electronic ADCs which exist today. On the way towards an integrated photonic ADC, a silicon photonic chip with core photonic components was fabricated and used to digitize a 10 GHz signal with 3.5 effective bits. In these experiments, two wavelength channels were implemented, providing the overall sampling rate of 2.1 GSa/s. To show that photonic ADCs with larger channel counts are possible, a dual 20-channel silicon filter bank has been demonstrated. PMID:22418205

  19. Information bottleneck based incremental fuzzy clustering for large biomedical data.

    Science.gov (United States)

    Liu, Yongli; Wan, Xing

    2016-08-01

    Incremental fuzzy clustering combines advantages of fuzzy clustering and incremental clustering, and therefore is important in classifying large biomedical literature. Conventional algorithms, suffering from data sparsity and high-dimensionality, often fail to produce reasonable results and may even assign all the objects to a single cluster. In this paper, we propose two incremental algorithms based on information bottleneck, Single-Pass fuzzy c-means (spFCM-IB) and Online fuzzy c-means (oFCM-IB). These two algorithms modify conventional algorithms by considering different weights for each centroid and object and scoring mutual information loss to measure the distance between centroids and objects. spFCM-IB and oFCM-IB are used to group a collection of biomedical text abstracts from Medline database. Experimental results show that clustering performances of our approaches are better than such prominent counterparts as spFCM, spHFCM, oFCM and oHFCM, in terms of accuracy. PMID:27260783

  20. HIV/AIDS: global trends, global funds and delivery bottlenecks

    Directory of Open Access Journals (Sweden)

    Hadingham Jacqui

    2005-08-01

    Full Text Available Abstract Globalisation affects all facets of human life, including health and well being. The HIV/AIDS epidemic has highlighted the global nature of human health and welfare and globalisation has given rise to a trend toward finding common solutions to global health challenges. Numerous international funds have been set up in recent times to address global health challenges such as HIV. However, despite increasingly large amounts of funding for health initiatives being made available to poorer regions of the world, HIV infection rates and prevalence continue to increase world wide. As a result, the AIDS epidemic is expanding and intensifying globally. Worst affected are undoubtedly the poorer regions of the world as combinations of poverty, disease, famine, political and economic instability and weak health infrastructure exacerbate the severe and far-reaching impacts of the epidemic. One of the major reasons for the apparent ineffectiveness of global interventions is historical weaknesses in the health systems of underdeveloped countries, which contribute to bottlenecks in the distribution and utilisation of funds. Strengthening these health systems, although a vital component in addressing the global epidemic, must however be accompanied by mitigation of other determinants as well. These are intrinsically complex and include social and environmental factors, sexual behaviour, issues of human rights and biological factors, all of which contribute to HIV transmission, progression and mortality. An equally important factor is ensuring an equitable balance between prevention and treatment programmes in order to holistically address the challenges presented by the epidemic.

  1. Overcoming bottlenecks in the membrane protein structural biology pipeline.

    Science.gov (United States)

    Hardy, David; Bill, Roslyn M; Jawhari, Anass; Rothnie, Alice J

    2016-06-15

    Membrane proteins account for a third of the eukaryotic proteome, but are greatly under-represented in the Protein Data Bank. Unfortunately, recent technological advances in X-ray crystallography and EM cannot account for the poor solubility and stability of membrane protein samples. A limitation of conventional detergent-based methods is that detergent molecules destabilize membrane proteins, leading to their aggregation. The use of orthologues, mutants and fusion tags has helped improve protein stability, but at the expense of not working with the sequence of interest. Novel detergents such as glucose neopentyl glycol (GNG), maltose neopentyl glycol (MNG) and calixarene-based detergents can improve protein stability without compromising their solubilizing properties. Styrene maleic acid lipid particles (SMALPs) focus on retaining the native lipid bilayer of a membrane protein during purification and biophysical analysis. Overcoming bottlenecks in the membrane protein structural biology pipeline, primarily by maintaining protein stability, will facilitate the elucidation of many more membrane protein structures in the near future. PMID:27284049

  2. Clogging transition of many-particle systems flowing through bottlenecks

    Science.gov (United States)

    Zuriguel, Iker; Parisi, Daniel Ricardo; Hidalgo, Raúl Cruz; Lozano, Celia; Janda, Alvaro; Gago, Paula Alejandra; Peralta, Juan Pablo; Ferrer, Luis Miguel; Pugnaloni, Luis Ariel; Clément, Eric; Maza, Diego; Pagonabarraga, Ignacio; Garcimartín, Angel

    2014-12-01

    When a large set of discrete bodies passes through a bottleneck, the flow may become intermittent due to the development of clogs that obstruct the constriction. Clogging is observed, for instance, in colloidal suspensions, granular materials and crowd swarming, where consequences may be dramatic. Despite its ubiquity, a general framework embracing research in such a wide variety of scenarios is still lacking. We show that in systems of very different nature and scale -including sheep herds, pedestrian crowds, assemblies of grains, and colloids- the probability distribution of time lapses between the passages of consecutive bodies exhibits a power-law tail with an exponent that depends on the system condition. Consequently, we identify the transition to clogging in terms of the divergence of the average time lapse. Such a unified description allows us to put forward a qualitative clogging state diagram whose most conspicuous feature is the presence of a length scale qualitatively related to the presence of a finite size orifice. This approach helps to understand paradoxical phenomena, such as the faster-is-slower effect predicted for pedestrians evacuating a room and might become a starting point for researchers working in a wide variety of situations where clogging represents a hindrance.

  3. Lexical Access and Dual-Task Performance: Determining the Locus of the Bottleneck

    Science.gov (United States)

    Allen, Phil

    2004-01-01

    During the two years of funding for NASA Grant "NCC21325, Lexical access and dual-task performance: Determining the locus of the bottleneck," we completed three experiments involving the psychological refractory period (PRP) and word frequency.

  4. Processing bottlenecks in dual-task performance: structural limitation or strategic postponement?

    Science.gov (United States)

    Ruthruff, E.; Pashler, H. E.; Klaassen, A.

    2001-01-01

    Recent evidence indicates that a central bottleneck causes much of the slowing that occurs when two tasks are performed at the same time. This bottleneck might reflect a structural limitation inherent in the cognitive architecture. Alternatively, the bottleneck might reflect strategic (i.e., voluntary) postponement, induced by instructions to emphasize one task over the other. To distinguish structural limitations from strategic postponement, we examine a new paradigm in which subjects are told to place equal emphasis on both tasks and to emit both responses at about the same time. An experiment using this paradigm demonstrated patterns of interference that cannot easily be attributed to strategic postponement, preparation effects, or conflicts in response production. The data conform closely to the predictions of structural central bottleneck models.

  5. Circuit model for spin-bottleneck resistance in magnetic-tunnel-junction devices

    OpenAIRE

    Jungwirth, T.; MacDonald, A. H.

    1998-01-01

    Spin-bottlenecks are created in magnetic-tunnel-junction devices by spatial inhomogeneity in the relative resistances for up and down spins. We propose a simple electrical circuit model for these devices which incorporates spin-bottleneck effects and can be used to calculate their overall resistance and magnetoresistance. The model permits a simple understanding of the dependence of device magnetoresistance on spin diffusion lengths, tunneling magnetoresistance, and majority and minority spin...

  6. A Framework for Accelerating Bottlenecks in GPU Execution with Assist Warps

    OpenAIRE

    Vijaykumar, Nandita; Pekhimenko, Gennady; Jog, Adwait; Ghose, Saugata; Bhowmick, Abhishek; Ausavarangnirun, Rachata; Das, Chita; Kandemir, Mahmut; Mowry, Todd C.; Mutlu, Onur

    2016-01-01

    Modern Graphics Processing Units (GPUs) are well provisioned to support the concurrent execution of thousands of threads. Unfortunately, different bottlenecks during execution and heterogeneous application requirements create imbalances in utilization of resources in the cores. For example, when a GPU is bottlenecked by the available off-chip memory bandwidth, its computational resources are often overwhelmingly idle, waiting for data from memory to arrive. This work describes the Core-Assist...

  7. BOTTLENECK ANALYSIS AND STRATEGIC PLANNING ON CHILDHOOD DIARRHEA MANAGEMENT IN 6 HIGH PRIORITY DISTRICTS OF GUJARAT

    OpenAIRE

    Rupani Mihir

    2015-01-01

    Introduction:Bottleneck Analysis and Strategic Planning exercise was carried out in 6 High Priority Districts (HPDs), under Call-to-Action for RMNCH+A strategy.Rationale: In spite of continued efforts, India is still lagging behind in its MDG goals.Objectives: To identify gaps in childhood diarrhea management and propose strategic options for the same.Materials and Methods: Bottleneck analysis exercisewas carried out based on the Tanahashi model, desk review and focused group discussions betw...

  8. Bottleneck Problem Solution using Biological Models of Attention in High Resolution Tracking Sensors

    OpenAIRE

    Fish, Alexander; Yadid-Pecht, Orly

    2005-01-01

    Every high resolution imaging system suffers from the bottleneck problem. This problem relates to the huge amount of data transmission from the sensor array to a digital signal processing (DSP) and to bottleneck in performance, caused by the requirement to process a large amount of information in parallel. The same problem exists in biological vision systems, where the information, sensed by many millions of receptors should be transmitted and processed in real time. Models, descr...

  9. Analysis of the pedestrian arching at bottleneck based on a bypassing behavior model

    Science.gov (United States)

    Tang, Ming; Jia, Hongfei; Ran, Bin; Li, Jun

    2016-07-01

    A bypassing behavior model was proposed, in which the local optimal decision behavior in the strategy level was modeled in velocity-time domain, to describe how pedestrians bypass the local obstacles considering the relative speed. The model contains (1) pedestrian visual and contact information acquisition; (2) motion state prediction of the local obstacles based on the visual and contact information; (3) pedestrian bypass strategy modeling in the velocity-time domain; (4) moving and overlapping solution. In the numerical solution, velocity domain was divided into n equal angle, the value of n ranges from 2 to infinity, the Manhattan space was refined gradually to Euclid Space accordingly, in which the movement of pedestrians was described. The model was applied to the analysis of pedestrian arching at the bottleneck in the emergent evacuation situation. (1) The results showed that the formation of the pedestrian arching at the bottleneck was deformation pressure, because many pedestrians try to pass through the bottleneck simultaneously, even in the absence of friction, the pedestrian arching still occurs; (2) In the emergent situation, we are more concerned about the bottleneck attribution of resistance to form the arching, the calculation and simulation results showed that the probability of an arching and the bottleneck width is an exponential function relationship, so when the stampede occurs in the middle of the bottleneck, the probability of arching will increase exponentially.

  10. The importance of bottlenecks in protein networks: correlation with gene essentiality and expression dynamics.

    Science.gov (United States)

    Yu, Haiyuan; Kim, Philip M; Sprecher, Emmett; Trifonov, Valery; Gerstein, Mark

    2007-04-20

    It has been a long-standing goal in systems biology to find relations between the topological properties and functional features of protein networks. However, most of the focus in network studies has been on highly connected proteins ("hubs"). As a complementary notion, it is possible to define bottlenecks as proteins with a high betweenness centrality (i.e., network nodes that have many "shortest paths" going through them, analogous to major bridges and tunnels on a highway map). Bottlenecks are, in fact, key connector proteins with surprising functional and dynamic properties. In particular, they are more likely to be essential proteins. In fact, in regulatory and other directed networks, betweenness (i.e., "bottleneck-ness") is a much more significant indicator of essentiality than degree (i.e., "hub-ness"). Furthermore, bottlenecks correspond to the dynamic components of the interaction network-they are significantly less well coexpressed with their neighbors than non-bottlenecks, implying that expression dynamics is wired into the network topology. PMID:17447836

  11. Central as well as peripheral attentional bottlenecks in dual-task performance activate lateral prefrontal cortices

    Directory of Open Access Journals (Sweden)

    Andre J Szameitat

    2016-03-01

    Full Text Available Human information processing suffers from severe limitations in parallel processing. In particular, when required to respond to two stimuli in rapid succession, processing bottlenecks may appear at central and peripheral stages of task processing. Importantly, it has been suggested that executive functions are needed to resolve the interference arising at such bottlenecks. The aims of the present study were to test whether central attentional limitations (i.e., bottleneck at the decisional response selection stage as well as peripheral limitations (i.e., bottleneck at response initiation both demand executive functions located in the lateral prefrontal cortex. For this, we re-analysed two previous studies, in which a total of 33 participants performed a dual-task according to the paradigm of the psychological refractory period (PRP during fMRI. In one study (N=17, the PRP task consisted of two two-choice response tasks known to suffer from a central bottleneck (CB group. In the other study (N=16, the PRP task consisted of two simple-response tasks known to suffer from a peripheral bottleneck (PB group. Both groups showed considerable dual-task costs in form of slowing of the second response in the dual-task (PRP effect. Imaging results are based on the subtraction of both single-tasks from the dual-task within each group. In the CB group, the bilateral middle frontal gyri and inferior frontal gyri were activated. Higher activation in these areas was associated with lower dual-task costs. In the PB group, the right middle frontal and inferior frontal gyrus were activated. Here, higher activation was associated with higher dual-task costs. In conclusion we suggest that central and peripheral bottlenecks both demand executive functions located in lateral prefrontal cortices. Differences between the CB and PB groups with respect to the exact prefrontal areas activated and the correlational patterns suggest that the executive functions resolving

  12. Automatic Stress Testing of Multi-tier Systems by Dynamic Bottleneck Switch Generation

    Science.gov (United States)

    Casale, Giuliano; Kalbasi, Amir; Krishnamurthy, Diwakar; Rolia, Jerry

    The performance of multi-tier systems is known to be significantly degraded by workloads that place bursty service demands on system resources. Burstiness can cause queueing delays, oversubscribe limited threading resources, and even cause dynamic bottleneck switches between resources. Thus, there is need for a methodology to create benchmarks with controlled burstiness and bottleneck switches to evaluate their impact on system performance. We tackle this problem using a model-based technique for the automatic and controlled generation of bursty benchmarks. Markov models are constructed in an automated manner to model the distribution of service demands placed by sessions of a given system on various system resources. The models are then used to derive session submission policies that result in user-specified levels of service demand burstiness for resources at the different tiers in a system. Our approach can also predict under what conditions these policies can create dynamic bottleneck switching among resources. A case study using a three-tier TPC-W testbed shows that our method is able to control and predict burstiness for session service demands. Further, results from the study demonstrate that our approach was able to inject controlled bottleneck switches. Experiments show that these bottleneck switches cause dramatic latency and throughput degradations that are not shown by the same session mix with non-bursty conditions.

  13. Selectivity of fish ladders: a bottleneck in Neotropical fish movement

    Directory of Open Access Journals (Sweden)

    Carlos Sérgio Agostinho

    2007-01-01

    their proportions in the downriver stretch: fish samples in the ladder were clearly dominated by a few species, including some that do not need to be translocated. Thus, selectivity constitutes an important bottleneck to initiatives for translocating fish aimed at conserving their stocks or biodiversity. It is urgent to review the decision-making process for the construction of fish passages and to evaluate the functioning of those already operating.Dezenas de escadas de peixes foram construídas em barragens de reservatórios brasileiros, mas são raros os estudos acerca de suas eficiências como instrumentos de conservação da ictiofauna Neotropical, em especial de espécies migradoras. Neste contexto, o presente estudo teve como objetivo avaliar a seletividade específica no ingresso e ascensão de peixes na escada localizada junto à barragem de Lajeado (UHE Luis Eduardo Magalhães, rio Tocantins. Amostragens foram realizadas mensalmente de novembro de 2002 a outubro de 2003 nos tanques de descanso da escada, utilizando tarrafas, e no trecho a jusante, utilizando redes de espera. A avaliação da seletividade no ingresso da escada foi realizada através da comparação da ocorrência, abundância relativa, dominância e congruência dos ranks de abundância de espécies migradoras e não migradoras na escada e no trecho imediatamente a jusante. A riqueza e abundância específica nos diferentes tanques de descanso foram utilizadas para avaliar a seletividade ao longo da escada. Os efeitos das variações temporais do nível hidrométrico de jusante e da velocidade de fluxo na seletividade foram também analisados. Das 130 espécies registradas a jusante, 63,2% foram capturadas na escada, com claro favorecimento das espécies migradoras. Entretanto, mais de 2/3 das capturas pertenceram a apenas três espécies (Rhaphiodon vulpinus, Psectrogaster amazonica e Oxydoras niger. Embora a maioria das espécies que ingressa na escada possa alcançar seu topo, constatou

  14. Population Bottlenecks Increase Additive Genetic Variance But Do Not Break a Selection Limit in Rainforest Drosophila

    DEFF Research Database (Denmark)

    van Heerwaarden, Belinda; Willi, Yvonne; Kristensen, Torsten N; Hoffmann, Ary A

    2008-01-01

    desiccation resistance in the rain forest-restricted fly Drosophila bunnanda. After one generation of single-pair mating, additive genetic variance for desiccation resistance increased to a significant level, on average higher than for the control lines. Line crosses revealed that both dominance and epistatic......According to neutral quantitative genetic theory, population bottlenecks are expected to decrease standing levels of additive genetic variance of quantitative traits. However, some empirical and theoretical results suggest that, if nonadditive genetic effects influence the trait, bottlenecks may...... actually increase additive genetic variance. This has been an important issue in conservation genetics where it has been suggested that small population size might actually experience an increase rather than a decrease in the rate of adaptation. Here we test if bottlenecks can break a selection limit for...

  15. Genetic bottlenecks during systemic movement of Cucumber mosaic virus vary in different host plants

    International Nuclear Information System (INIS)

    Genetic bottlenecks are stochastic events that narrow variation in a population. We compared bottlenecks during the systemic infection of Cucumber mosaic virus (CMV) in four host plants. We mechanically inoculated an artificial population of twelve CMV mutants to young leaves of tomato, pepper, Nicotiana benthamiana, and squash. The inoculated leaves and primary and secondary systemically infected leaves were sampled at 2, 10, and 15 days post-inoculation. All twelve mutants were detected in all of the inoculated leaves. The number of mutants recovered from the systemically infected leaves of all host species was reduced significantly, indicating bottlenecks in systemic movement. The recovery frequencies of a few of the mutants were significantly different in each host probably due to host-specific selective forces. These results have implications for the differences in virus population variation that is seen in different host plants.

  16. A recent bottleneck of Y chromosome diversity coincides with a global change in culture

    KAUST Repository

    Karmin, Monika

    2015-04-30

    It is commonly thought that human genetic diversity in non-African populations was shaped primarily by an out-of-Africa dispersal 50–100 thousand yr ago (kya). Here, we present a study of 456 geographically diverse high-coverage Y chromosome sequences, including 299 newly reported samples. Applying ancient DNA calibration, we date the Y-chromosomal most recent common ancestor (MRCA) in Africa at 254 (95% CI 192–307) kya and detect a cluster of major non-African founder haplogroups in a narrow time interval at 47–52 kya, consistent with a rapid initial colonization model of Eurasia and Oceania after the out-of-Africa bottleneck. In contrast to demographic reconstructions based on mtDNA, we infer a second strong bottleneck in Y-chromosome lineages dating to the last 10 ky. We hypothesize that this bottleneck is caused by cultural changes affecting variance of reproductive success among males.

  17. Exposure to a novel environment in conjunction with serial bottlenecks increases phenotypic and additive variation of a quantitative trait

    Directory of Open Access Journals (Sweden)

    T.E. Callicrate

    2012-09-01

    Full Text Available Demographic bottlenecks were replicated in laboratory conditions using Tribolium castaneum in order to determine how additive genetic variance, and therefore adaptive potential, may be affected by a novel environment. A two-level bottleneck was imposed. The first level was a 100-individual bottleneck (five replicates. After three generations at population size 100, the second bottleneck consisted of a single mating pair (15 sub-replicates stemming from each first-level replicate. Two growth media (environments, standard (wheat flour or novel (wheat bran, were used in the sub-replicates to simulate translocation to an environment with a different foraging substrate. Sub-replicates were managed for slow population growth during six generations to population size 50 and were thus maintained for nine additional generations. Variance in pupa weight in generation 16 was affected by drift from the first and second-level bottlenecks (flour: N=382, bran: N=470 pupae, both P < 0.0001 at each bottleneck level. Total phenotypic variance was determined from the progeny of the single pair matings and was larger for bottlenecks occurring in bran than in flour, P < 0.01 (F469,381 = 1.29. Additive variance was also larger in bran than flour bottlenecks, P < 0.01 (F469,381 = 1.38. These results indicate that bottlenecks occurring in a novel environment could potentially increase the effectiveness of selection by bolstering additive variance.

  18. Memory bottlenecks and memory contention in multi-core Monte Carlo transport codes

    International Nuclear Information System (INIS)

    Highlights: • The performance of nuclear reactor Monte Carlo transport applications is examined. • A “proxy-application” (XSBench) is presented representing the key kernel. • In-depth performance analyses reveal the algorithm is bottlenecked by bandwidth. • Strategies are discussed to improve scalability on next generation HPC systems. - Abstract: We have extracted a kernel that executes only the most computationally expensive steps of the Monte Carlo particle transport algorithm – the calculation of macroscopic cross sections – in an effort to expose bottlenecks within multi-core, shared memory architectures

  19. Reducing the Analytical Bottleneck for Domain Scientists: Lessons from a Climate Data Visualization Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Dasgupta, Aritra; Poco, Jorge; Bertini, Enrico; Silva, Claudio T.

    2016-01-31

    The gap between large-scale data production rate and the rate of generation of data-driven scientific insights has led to an analytical bottleneck in scientific domains like climate, biology, etc. This is primarily due to the lack of innovative analytical tools that can help scientists efficiently analyze and explore alternative hypotheses about the data, and communicate their findings effectively to a broad audience. In this paper, by reflecting on a set of successful collaborative research efforts between with a group of climate scientists and visualization researchers, we introspect how interactive visualization can help reduce the analytical bottleneck for domain scientists.

  20. Temperature dependence of the polariton relaxation bottleneck in a GaN microcavity

    Energy Technology Data Exchange (ETDEWEB)

    Stokker-Cheregi, F. [LENS and Department of Physics, University of Florence (Italy); NILPRP, Lasers Department, Magurele, Bucharest (Romania); Vinattieri, A.; Colocci, M.; Gurioli, M. [LENS and Department of Physics, University of Florence (Italy); Semond, F.; Leroux, M.; Massies, J. [CRHEA-CNRS, Valbonne (France); Sellers, I.R. [CRHEA-CNRS, Valbonne (France); Department of Physics, University of Buffalo, NY (United States)

    2008-07-01

    We present an experimental study aimed to investigate discuss the possible presence of a phonon bottleneck in a GaN bulk microcavity. Clear anticrossing between the lower (LP) and upper polariton (UP) branches has been observed up to room temperature in photoluminescence (PL) by angular measurements with a Rabi splitting of the order of 30 meV. In order to determine the presence of a relaxation bottleneck, angular PL measurements have been performed at different temperatures for negative detuning. At low T the PL shows a clear maximum, at the angle corresponding to the resonance between the exciton and the photon modes, which is an experimental demonstration of the presence of a relaxation bottleneck. The PL enhancement in resonance condition is suppressed with increasing T and it almost disappears at room temperature. We therefore demonstrate that the exciton-phonon interaction washes out the polariton bottleneck in GaN MCs at room temperature. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  1. Identifikasi Bottleneck pada Hasil Ekstraksi Proses Bisnis ERP dengan Membandingkan Algoritma Alpha++ dan Heuristics Miner

    Directory of Open Access Journals (Sweden)

    Laeila Mardhatillah

    2012-09-01

    Full Text Available Saat ini banyak perusahaan menggunakan sistem informasi untuk menunjang proses bisnis. Namun kenyataannya hanya beberapa perusahaan yang melakukan evaluasi untuk proses bisnis pada sistem informasi tersebut. Evaluasi ini didapat dari data Event log yang merupakan hasil proses ekstrasi ERP. Cara melakukan evaluasi yaitu dengan process mining. Process mining berfungsi untuk menggali proses transaksi sehingga terbentuk suatu workflow proses bisnis yang actual. Workflow proses bisnis ini akan digambarkan dalam bentuk Petri Net, selanjutnya dari Petri Net inilah akan dilakukan analisis untuk mengidentifikasi adanya BottleneckBottleneck merupakan peristiwa pada suatu transaksi yang memiliki waktu tunggu yang lebih lama dibandingkan transaksi lainnya dalam suatu proses bisnis. Dengan adanya PROM Tools maka penggambaran mengenai proses bisnis ERP dapat terbentuk. Penggambaran model tersebut menggunakan dua algoritma, yaitu Algoritma Alpha ++ dan Heuristics Miner. Kedua algoritma ini digunakan untuk mencari perbedaan bottleneck yang terjadi. Dari penelitian didapatkan  hasil bahwa algoritma sangat mempengaruhi letak bottleneck. Letak tersebut didasarkan pada perhitungan waktu token yang ada pada place (tempat antara dua transisi atau dua transaksi saat terbentuk model.

  2. Consequences of the Now-or-Never bottleneck for signed versus spoken languages.

    Science.gov (United States)

    Emmorey, Karen

    2016-01-01

    Signed and spoken languages emerge, change, are acquired, and are processed under distinct perceptual, motor, and memory constraints. Therefore, the Now-or-Never bottleneck has different ramifications for these languages, which are highlighted in this commentary. The extent to which typological differences in linguistic structure can be traced to processing differences provides unique evidence for the claim that structure is processing. PMID:27562833

  3. South West Georgia: an important bottleneck for raptor migration during autumn

    NARCIS (Netherlands)

    B. Verhelst; J. Jansen; W. Vansteelant

    2011-01-01

    Counts of migrating raptors at Batumi, Georgia, revealed the eastern Black Sea coast to form one of the most important bottlenecks for raptor migration during autumn in the Eurasian-African migration system. Totals for 10 species (European Honey-buzzard Pernis apivorus, Steppe Buzzard Buteo buteo vu

  4. Genetic variability and bottleneck detection of four Tricholoma matsutake populations from northeastern and southwestern China.

    Science.gov (United States)

    Zeng, Dong-Fang; Chen, Bin

    2015-08-01

    The excessive commercial collection of matsutake mushrooms can lead to extreme reduction of population size, which may cause genetic bottleneck and decrease genetic diversity of Tricholoma matsutake. Here, six polymorphic microsatellite loci markers were used to examine the genetic diversity of four natural T. matsutake populations from two main producing regions of China. The minimum combinations of four loci were able to discriminate total 86 sampled individuals with distinctive multilocus genotypes. Our analysis of molecular variance (AMOVA) revealed that about 80% and 20% of the overall genetic variation were respectively partitioned within and among populations. The principal-coordinate analyses (PCA) distinguished the four tested populations into three genetic clusters, each of which was correlated with respective endemic host plants on a geographical basis. The AMOVA, PCA and pairwise population FST estimates consistently displayed the same genetic divergence patterns and spatial structure of T. matsutake mediated by host plants in China. The significant heterozygosity excesses demonstrated that a recent genetic bottleneck occurred in each population tested. The complementary M-ratio test indicated past genetic bottleneck events over longer periods. Only four individuals were identified as putative first generation migrants within northeastern China, which implies restricted interpopulation gene flow in T. matsutake. We discuss that the significant genetic differentiation among populations of T. matsutake is most likely a function of host adaptation, host specificity, genetic bottleneck, limited dispersal and habitat fragmentation. PMID:25682708

  5. Achievements & bottlenecks in humanitarian demining EU-funded research: Final results from the EC DELVE project

    NARCIS (Netherlands)

    Sahli, H.; Bruschini, C.; Kempen, L. van; Schleijpen, H.M.A.; Breejen, E. den

    2008-01-01

    The EC DELVE Support Action project has analyzed the bottlenecks in the transfer of Humanitarian Demining (HD) technology from technology development to the use in the field, and drawn some lessons learned, basing itself on the assessment of the European Humanitarian Demining Research and Technology

  6. The strength and timing of the mitochondrial bottleneck in salmon suggests a conserved mechanism in vertebrates.

    Directory of Open Access Journals (Sweden)

    Jonci N Wolff

    Full Text Available In most species mitochondrial DNA (mtDNA is inherited maternally in an apparently clonal fashion, although how this is achieved remains uncertain. Population genetic studies show not only that individuals can harbor more than one type of mtDNA (heteroplasmy but that heteroplasmy is common and widespread across a diversity of taxa. Females harboring a mixture of mtDNAs may transmit varying proportions of each mtDNA type (haplotype to their offspring. However, mtDNA variants are also observed to segregate rapidly between generations despite the high mtDNA copy number in the oocyte, which suggests a genetic bottleneck acts during mtDNA transmission. Understanding the size and timing of this bottleneck is important for interpreting population genetic relationships and for predicting the inheritance of mtDNA based disease, but despite its importance the underlying mechanisms remain unclear. Empirical studies, restricted to mice, have shown that the mtDNA bottleneck could act either at embryogenesis, oogenesis or both. To investigate whether the size and timing of the mitochondrial bottleneck is conserved between distant vertebrates, we measured the genetic variance in mtDNA heteroplasmy at three developmental stages (female, ova and fry in chinook salmon and applied a new mathematical model to estimate the number of segregating units (N(e of the mitochondrial bottleneck between each stage. Using these data we estimate values for mtDNA Ne of 88.3 for oogenesis, and 80.3 for embryogenesis. Our results confirm the presence of a mitochondrial bottleneck in fish, and show that segregation of mtDNA variation is effectively complete by the end of oogenesis. Considering the extensive differences in reproductive physiology between fish and mammals, our results suggest the mechanism underlying the mtDNA bottleneck is conserved in these distant vertebrates both in terms of it magnitude and timing. This finding may lead to improvements in our understanding of

  7. Dual-task performance with ideomotor-compatible tasks: is the central processing bottleneck intact, bypassed, or shifted in locus?

    Science.gov (United States)

    Lien, Mei-Ching; McCann, Robert S.; Ruthruff, Eric; Proctor, Robert W.

    2005-01-01

    The present study examined whether the central bottleneck, assumed to be primarily responsible for the psychological refractory period (PRP) effect, is intact, bypassed, or shifted in locus with ideomotor (IM)-compatible tasks. In 4 experiments, factorial combinations of IM- and non-IM-compatible tasks were used for Task 1 and Task 2. All experiments showed substantial PRP effects, with a strong dependency between Task 1 and Task 2 response times. These findings, along with model-based simulations, indicate that the processing bottleneck was not bypassed, even with two IM-compatible tasks. Nevertheless, systematic changes in the PRP and correspondence effects across experiments suggest that IM compatibility shifted the locus of the bottleneck. The findings favor an engage-bottleneck-later hypothesis, whereby parallelism between tasks occurs deeper into the processing stream for IM- than for non-IM-compatible tasks, without the bottleneck being actually eliminated.

  8. Note: Inhibiting bottleneck corrosion in electrical calcium tests for ultra-barrier measurements

    Science.gov (United States)

    Nehm, F.; Müller-Meskamp, L.; Klumbies, H.; Leo, K.

    2015-12-01

    A major failure mechanism is identified in electrical calcium corrosion tests for quality assessment of high-end application moisture barriers. Accelerated calcium corrosion is found at the calcium/electrode junction, leading to an electrical bottleneck. This causes test failure not related to overall calcium loss. The likely cause is a difference in electrochemical potential between the aluminum electrodes and the calcium sensor, resulting in a corrosion element. As a solution, a thin, full-area copper layer is introduced below the calcium, shifting the corrosion element to the calcium/copper junction and inhibiting bottleneck degradation. Using the copper layer improves the level of sensitivity for the water vapor transmission rate (WVTR) by over one order of magnitude. Thin-film encapsulated samples with 20 nm of atomic layer deposited alumina barriers this way exhibit WVTRs of 6 × 10-5 g(H2O)/m2/d at 38 °C, 90% relative humidity.

  9. Note: Inhibiting bottleneck corrosion in electrical calcium tests for ultra-barrier measurements

    International Nuclear Information System (INIS)

    A major failure mechanism is identified in electrical calcium corrosion tests for quality assessment of high-end application moisture barriers. Accelerated calcium corrosion is found at the calcium/electrode junction, leading to an electrical bottleneck. This causes test failure not related to overall calcium loss. The likely cause is a difference in electrochemical potential between the aluminum electrodes and the calcium sensor, resulting in a corrosion element. As a solution, a thin, full-area copper layer is introduced below the calcium, shifting the corrosion element to the calcium/copper junction and inhibiting bottleneck degradation. Using the copper layer improves the level of sensitivity for the water vapor transmission rate (WVTR) by over one order of magnitude. Thin-film encapsulated samples with 20 nm of atomic layer deposited alumina barriers this way exhibit WVTRs of 6 × 10−5 g(H2O)/m2/d at 38 °C, 90% relative humidity

  10. Understanding of empty container movement: A study on a bottleneck at an off-dock depot

    Science.gov (United States)

    Zain, Rosmaizura Mohd; Rahman, Mohd Nizam Ab; Nopiah, Zulkifli Mohd; Saibani, Nizaroyani

    2014-09-01

    Port not only function as connections between marine and land transportation but also as core business areas. In a port terminal, available space is limited, but the influx of container is growing. The off-dock depot is one of the key supply chain players that hold empty containers in the inventory. Therefore, this paper aims to identify the main factors of bottlenecks or congestion that hinder the rapid movement of empty containers from the off-dock depot to the customers. Thirty interviews were conducted with individuals who are key players in the container supply chain. The data were analyzed using Atlas.ti software and the analytic hierarchy process to rank the priority factors of bottlenecks. Findings show that several pertinent factors act as barriers to the key players in the container movement in the day-to-day operations. In future studies, strategies to overcome fragmentation in the container supply chain and logistics must be determined.

  11. Zero-temperature quantum annealing bottlenecks in the spin-glass phase

    Science.gov (United States)

    Knysh, Sergey

    2016-08-01

    A promising approach to solving hard binary optimization problems is quantum adiabatic annealing in a transverse magnetic field. An instantaneous ground state--initially a symmetric superposition of all possible assignments of N qubits--is closely tracked as it becomes more and more localized near the global minimum of the classical energy. Regions where the energy gap to excited states is small (for instance at the phase transition) are the algorithm's bottlenecks. Here I show how for large problems the complexity becomes dominated by O(log N) bottlenecks inside the spin-glass phase, where the gap scales as a stretched exponential. For smaller N, only the gap at the critical point is relevant, where it scales polynomially, as long as the phase transition is second order. This phenomenon is demonstrated rigorously for the two-pattern Gaussian Hopfield model. Qualitative comparison with the Sherrington-Kirkpatrick model leads to similar conclusions.

  12. Phonon bottleneck in GaAs/AlxGa1−xAs quantum dots

    International Nuclear Information System (INIS)

    We report low-temperature photoluminescence measurements on highly-uniform GaAs/AlxGa1−xAs quantum dots grown by droplet epitaxy. Recombination between confined electrons and holes bound to carbon acceptors in the dots allow us to determine the energies of the confined states in the system, as confirmed by effective mass calculations. The presence of acceptor-bound holes in the quantum dots gives rise to a striking observation of the phonon-bottleneck effect

  13. CO2 capture enhancement in InOF-1 via the bottleneck effect of confined ethanol.

    Science.gov (United States)

    Peralta, Ricardo A; Campos-Reales-Pineda, Alberto; Pfeiffer, Heriberto; Álvarez, J Raziel; Zárate, J Antonio; Balmaseda, Jorge; González-Zamora, Eduardo; Martínez, Ana; Martínez-Otero, Diego; Jancik, Vojtech; Ibarra, Ilich A

    2016-08-11

    CO2 capture of InOF-1 was enhanced 3.6-fold, at 1 bar and 30 °C, by confining EtOH within its pores. Direct visualisation by single crystal X-ray diffraction revealed that EtOH divides InOF-1 channels in wide sections separated by "bottlenecks" caused by EtOH molecules bonded to the μ2-OH functional groups of InOF-1. PMID:27469274

  14. Why don’t we see changes?: The role of attentional bottlenecks and limited visual memory

    OpenAIRE

    Jeremy M Wolfe; Reinecke, Andrea; BRAWN, PETER

    2006-01-01

    Seven experiments explore the role of bottlenecks in selective attention and access to visual short-term memory in the failure of observers to identify clearly visible changes in otherwise stable visual displays. Experiment One shows that observers fail to register a color change in an object even if they are cued to the location of the object by a transient at that location as the change is occurring. Experiment Two shows the same for orientation change. In Experiments Three and Four, attent...

  15. Germline Bottlenecks, Biparental Inheritance and Selection on Mitochondrial Variants: A Two-Level Selection Model

    OpenAIRE

    Roze, Denis; Rousset, François; Michalakis, Yannis

    2005-01-01

    Selection on mitochondrial mutations potentially occurs at different levels: at the mitochondria, cell, and organism levels. Several factors affect the strength of selection at these different levels; in particular, mitochondrial bottlenecks during germline development and reduced paternal transmission decrease the genetic variance within cells, while they increase the variance between cells and between organisms, thus decreasing the strength of selection within cells and increasing the stren...

  16. An assessment of The Capacity Drops at The Bottleneck Segments: A review on the existing methodologies

    Directory of Open Access Journals (Sweden)

    Sugiarto Sugiarto

    2015-08-01

    Full Text Available The term of capacity is very useful to quantify the ability of transport facilities in terms of carrying traffic. The capacity of the road is an essential ingredient in the planning, design, and operation of roadways. It is desirable for traffic analyst to be able to predict the time and places where congestion will occur and the volumes to be expected. Most of urbanized areas have been experiencing of traffic congestion problems particularly at urban arterial systems. High traffic demand and limited supply of roadways are always the main factors produced traffic congestion. However, there are other sources of local and temporal congestion, such as uncontrolled access point, median opening and on-street parking activities, which are caused a reduction of roadway capacity during peak operations. Those locations could result in reduction of travel speed and road, as known as hidden bottlenecks. This is bottleneck which is without any changes in geometric of the segments. The Indonesian Highway Capacity Manual (IHCM, 1997 is used to assess urban arterial systems till current days. IHCM provides a static method for examining the capacityand does not systematically take into account of bottleneck activities. However, bottleneck activities create interruption smooth traffic flow along arterial streets, which in turns stimulate related problems, such as, excessive air pollution, additional energy consumption and driver’s frustration due to traffic jammed. This condition could happen simultaneously; mostly repetitive and predictable in same peak hour demands. Therefore, this paper carefully summarize on the existing methodologies considering required data, handled data processing and expected output of each proposed of analysis. We further notice that dynamic approach could be more appropriated for analyzing temporal congestion segments (median opening, on street parking, etc.. Method of oblique cumulative plot seems to be more applicable in terms of

  17. Emerging from the bottleneck: Benefits of the comparative approach to modern neuroscience

    OpenAIRE

    Brenowitz, Eliot A.; Zakon, Harold H.

    2015-01-01

    Neuroscience historically exploited a wide diversity of animal taxa. Recently, however, research focused increasingly on a few model species. This trend accelerated with the genetic revolution, as genomic sequences and genetic tools became available for a few species, which formed a bottleneck. This coalescence on a small set of model species comes with several costs often not considered, especially in the current drive to use mice explicitly as models for human diseases. Comparative studies ...

  18. Bottlenecks and opportunities for quality improvement in fresh pineapple supply chains in Benin

    OpenAIRE

    Fassinou Hotegni, V.N.; Lommen, W.J.M.; Vorst, van de, GAL Alfred; Agbossou, E.K.; Struik, P.C.

    2014-01-01

    This study mapped and diagnosed the fresh pineapple supply chains in Benin to identify bottlenecks in pineapple quality improvement for different markets. A research framework was defined that comprised all relevant aspects to be researched. After 54 semi-structured interviews with key informants, 173 structured interviews were held with actor groups. The chain diagnosis showed there was no concordance between actor groups in which quality attribute they valued most. Moreover, pineapple quali...

  19. Potential and bottlenecks of the carbon market: The case of a developing country, Nepal

    International Nuclear Information System (INIS)

    The majority of clean development mechanism (CDM) projects are confined to a few countries. For many developing nations, entry into the carbon market, either through CDM or others, has been difficult. Thus, rationalizing CDM projects and the carbon market as a tool for sustainable development is often questioned. Many developing countries, such as Nepal, lack a quantification of CO2 reduction potential and an assessment of bottlenecks necessary for the carbon market. In this context, this paper assesses the potential emission reductions from major sectors of Nepal and the accompanying bottlenecks of the carbon market. The analyses provide indications of the type and scale of the carbon mitigation opportunities in key sectors such as waste management, biogas utilization, promotion of electric vehicles, rice cultivation, bio-energy utilization, brick making, hydropower development and a few others. These might be helpful to decision-makers in Nepal as well as to the process of re-orienting CDM and other carbon markets to better understand the bottlenecks of developing countries.

  20. Empirical Features of Spontaneous and Induced Traffic Breakdowns in Free Flow at Highway Bottlenecks

    CERN Document Server

    Kerner, Boris S; Klenov, Sergey L; Rehborn, Hubert; Leibel, Michael

    2015-01-01

    Based on an empirical study of real field traffic data measured in 1996--2014 through road detectors installed on German freeways, we reveal physical features of empirical nuclei for spontaneous traffic breakdown in free flow at highway bottlenecks. It is shown that the source of a nucleus for traffic breakdown is the solely difference between empirical spontaneous and induced traffic breakdowns at a highway bottleneck. Microscopic traffic simulations with a stochastic traffic flow model in the framework of three-phase theory explain the empirical findings. It turns out that in the most cases, a nucleus for empirical spontaneous traffic breakdown occurs through an interaction of one of waves in free flow with an empirical permanent speed disturbance localized at a highway bottleneck. The wave is a localized structure in free flow, in which the total flow rate is larger and the speed averaged across the highway is smaller than outside the wave. The waves in free flow appear due to oscilations in the percentage...

  1. Incident and Traffic-Bottleneck Detection Algorithm in High-Resolution Remote Sensing Imagery

    Directory of Open Access Journals (Sweden)

    S.M.M. Kahaki

    2012-09-01

    Full Text Available One of the most important methods to solve traffic congestion is to detect the incident state of a roadway. This paper describes the development of a method for road traffic monitoring aimed at the acquisition and analysis of remote sensing imagery. We propose a strategy for road extraction, vehicle detection and incident detection from remote sensing imagery using techniques based on neural networks, Radon transform for angle detection and traffic-flow measurements. Traffic-bottleneck detection is another method that is proposed for recognizing incidents in both offline and real-time mode. Traffic flows and incidents are extracted from aerial images of bottleneck zones. The results show that the proposed approach has a reasonable detection performance compared to other methods. The best performance of the learning system was a detection rate of 87% and a false alarm rate of less than 18% on 45 aerial images of roadways. The performance of the traffic-bottleneck detection method had a detection rate of 87.5%.

  2. Maternal age effect and severe germ-line bottleneck in the inheritance of human mitochondrial DNA

    DEFF Research Database (Denmark)

    Rebolledo-Jaramillo, Boris; Su, Marcia Shu-Wei; Stoler, Nicholas;

    2014-01-01

    The manifestation of mitochondrial DNA (mtDNA) diseases depends on the frequency of heteroplasmy (the presence of several alleles in an individual), yet its transmission across generations cannot be readily predicted owing to a lack of data on the size of the mtDNA bottleneck during oogenesis. For...... deleterious heteroplasmies, a severe bottleneck may abruptly transform a benign (low) frequency in a mother into a disease-causing (high) frequency in her child. Here we present a high-resolution study of heteroplasmy transmission conducted on blood and buccal mtDNA of 39 healthy mother-child pairs of...... generations and estimated the effective size of the germ-line mtDNA bottleneck at only ∼30-35 (interquartile range from 9 to 141). Accounting for heteroplasmies, we estimated the mtDNA germ-line mutation rate at 1.3 × 10(-8) (interquartile range from 4.2 × 10(-9) to 4.1 × 10(-8)) mutations per site per year...

  3. Circulating virus load determines the size of bottlenecks in viral populations progressing within a host.

    Directory of Open Access Journals (Sweden)

    Serafín Gutiérrez

    Full Text Available For any organism, population size, and fluctuations thereof, are of primary importance in determining the forces driving its evolution. This is particularly true for viruses--rapidly evolving entities that form populations with transient and explosive expansions alternating with phases of migration, resulting in strong population bottlenecks and associated founder effects that increase genetic drift. A typical illustration of this pattern is the progression of viral disease within a eukaryotic host, where such demographic fluctuations are a key factor in the emergence of new variants with altered virulence. Viruses initiate replication in one or only a few infection foci, then move through the vasculature to seed secondary infection sites and so invade distant organs and tissues. Founder effects during this within-host colonization might depend on the concentration of infectious units accumulating and circulating in the vasculature, as this represents the infection dose reaching new organs or "territories". Surprisingly, whether or not the easily measurable circulating (plasma virus load directly drives the size of population bottlenecks during host colonization has not been documented in animal viruses, while in plants the virus load within the sap has never been estimated. Here, we address this important question by monitoring both the virus concentration flowing in host plant sap, and the number of viral genomes founding the population in each successive new leaf. Our results clearly indicate that the concentration of circulating viruses directly determines the size of bottlenecks, which hence controls founder effects and effective population size during disease progression within a host.

  4. Lagrangian-averaged model for magnetohydrodynamic turbulence and the absence of bottlenecks.

    Science.gov (United States)

    Pietarila Graham, Jonathan; Mininni, Pablo D; Pouquet, Annick

    2009-07-01

    We demonstrate that, for the case of quasiequipartition between the velocity and the magnetic field, the Lagrangian-averaged magnetohydrodynamics (LAMHD) alpha model reproduces well both the large-scale and the small-scale properties of turbulent flows; in particular, it displays no increased (superfilter) bottleneck effect with its ensuing enhanced energy spectrum at the onset of the subfilter scales. This is in contrast to the case of the neutral fluid in which the Lagrangian-averaged Navier-Stokes alpha model is somewhat limited in its applications because of the formation of spatial regions with no internal degrees of freedom and subsequent contamination of superfilter-scale spectral properties. We argue that, as the Lorentz force breaks the conservation of circulation and enables spectrally nonlocal energy transfer (associated with Alfvén waves), it is responsible for the absence of a viscous bottleneck in magnetohydrodynamics (MHD), as compared to the fluid case. As LAMHD preserves Alfvén waves and the circulation properties of MHD, there is also no (superfilter) bottleneck found in LAMHD, making this method capable of large reductions in required numerical degrees of freedom; specifically, we find a reduction factor of approximately 200 when compared to a direct numerical simulation on a large grid of 1536;{3} points at the same Reynolds number. PMID:19658812

  5. On the prospect of identifying adaptive loci in recently bottlenecked populations.

    Directory of Open Access Journals (Sweden)

    Yu-Ping Poh

    Full Text Available Identifying adaptively important loci in recently bottlenecked populations - be it natural selection acting on a population following the colonization of novel habitats in the wild, or artificial selection during the domestication of a breed - remains a major challenge. Here we report the results of a simulation study examining the performance of available population-genetic tools for identifying genomic regions under selection. To illustrate our findings, we examined the interplay between selection and demography in two species of Peromyscus mice, for which we have independent evidence of selection acting on phenotype as well as functional evidence identifying the underlying genotype. With this unusual information, we tested whether population-genetic-based approaches could have been utilized to identify the adaptive locus. Contrary to published claims, we conclude that the use of the background site frequency spectrum as a null model is largely ineffective in bottlenecked populations. Results are quantified both for site frequency spectrum and linkage disequilibrium-based predictions, and are found to hold true across a large parameter space that encompasses many species and populations currently under study. These results suggest that the genomic footprint left by selection on both new and standing variation in strongly bottlenecked populations will be difficult, if not impossible, to find using current approaches.

  6. Modeling the Impact of Border Crossing Bottlenecks on Supply Chain Disruption Risk

    Directory of Open Access Journals (Sweden)

    Shaheen Sardar

    2015-04-01

    Full Text Available In order to remain competitive, companies outsource the manufacturing process to global markets. Globalization requires shipping of goods across borders. Cross border movement of goods faces diverse difficulties and creates bottlenecks in the supply chain. Complex products involve numerous parts and complications in the assembly process, resulting in multiple border-crossings with varying level of complexity across multiple countries before reaching to the customers. This activity contributes to the supply chain disruption risk. Border crossing is unavoidable in global supply chains, and how to integrate border crossing complexity in supply chain models is an unresolved issue. This paper suggests an approach to quantify the border crossing complexity and its impact on the supply chain disruption risk in the global outsourcing environment. Results show that key factors which contribute to border crossing complexity include product complexity, trade procedures, and various bottlenecks at each bordercrossing. Based on results drawn from the quantitative analysis, we propose several strategies to manage the impact of border crossing bottlenecks. The focus of this research is the manufacturing companies which are involved in managing the global supply chains.

  7. BOTTLENECK ANALYSIS AND STRATEGIC PLANNING ON CHILDHOOD DIARRHEA MANAGEMENT IN 6 HIGH PRIORITY DISTRICTS OF GUJARAT

    Directory of Open Access Journals (Sweden)

    Rupani Mihir

    2015-01-01

    Full Text Available Introduction:Bottleneck Analysis and Strategic Planning exercise was carried out in 6 High Priority Districts (HPDs, under Call-to-Action for RMNCH+A strategy.Rationale: In spite of continued efforts, India is still lagging behind in its MDG goals.Objectives: To identify gaps in childhood diarrhea management and propose strategic options for the same.Materials and Methods: Bottleneck analysis exercisewas carried out based on the Tanahashi model, desk review and focused group discussions between district officials, front-line workers and UNICEF officials. These bottlenecks were pertaining to the availability, accessibility, utilization of services and quality of services being provided by the health department.Elaborating the Tanahashi model for the 6 HPDs, 94% of the front-line workers (FLWs had stock of Zinc-ORS; 88% FLWs were trained in diarrhea management; 98% villages had at least one FLW trained in diarrhea management; health care seeking for diarrhea cases was 17%; 5.1% diarrhea cases received Zinc-ORS from health worker and 2.4% care takers prepared Zinc-ORS in safe drinking water.Results: The major bottlenecks identified for Childhood Diarrhea management in the 6 High Priority Districts were poor demand generation, unsafe drinking water, poor access to improved sanitation facility and lack of equitable distribution of Zinc-ORS till the front-line worker level. The main strategic options that were suggested for relieving these bottlenecks were Zinc-ORS roll out in scale-up districts, develop IEC/BCC plan for childhood diarrhea management at state/district level, use of Drug Logistics Information Management System (DLIMS software for supply chain management of Zinc-ORS, strengthening of chlorination activity at household level, monitoring implementation of Nirmal Bharat Abhiyaan (NBA for constructing improved sanitation facilities at household level and to develop an IEC/BCC plan for hygiene promotion and usage of sanitary latrines

  8. Local time stepping on high performance computing architectures: mitigating CFL bottlenecks for large-scale wave propagation

    OpenAIRE

    Rietmann, Max; Schenk, Olaf

    2015-01-01

    Modeling problems that require the simulation of hyperbolic PDEs (wave equations) on large heterogeneous domains have potentially many bottlenecks. We attack this problem through two techniques: the massively parallel capabilities of graphics processors (GPUs) and local time stepping (LTS) to mitigate any CFL bottlenecks on a multiscale mesh. Many modern supercomputing centers are installing GPUs due to their high performance, and extending existing seismic wave-propagation software to ...

  9. Anatomy of a bottleneck: diagnosing factors limiting population growth in the Puerto Rican parrot

    Science.gov (United States)

    Beissenger, S.R.; Wunderle, J.M., Jr.; Meyers, J.M.; Saether, B.-E.; Engen, S.

    2008-01-01

    The relative importance of genetic, demographic, environmental, and catastrophic processes that maintain population bottlenecks has received little consideration. We evaluate the role of these factors in maintaining the Puerto Rican Parrot (Amazona vittata) in a prolonged bottleneck from 1973 through 2000 despite intensive conservation efforts. We first conduct a risk analysis, then examine evidence for the importance of specific processes maintaining the bottleneck using the multiple competing hypotheses approach, and finally integrate these results through a sensitivity analysis of a demographic model using life-stage simulation analysis (LSA) to determine the relative importance of genetic, demographic, environmental, and catastrophic processes on population growth. Annual population growth has been slow and variable (1.0 6 5.2 parrots per year, or an average k?1.05 6 0.19) from 16 parrots (1973) to a high of 40-42 birds (1997-1998). A risk analysis based on population prediction intervals (PPI) indicates great risk and large uncertainty, with a range of 22?83 birds in the 90% PPI only five years into the future. Four primary factors (reduced hatching success due to inbreeding, failure of adults to nest, nest failure due to nongenetic causes, and reduced survival of adults and juveniles) were responsible for maintaining the bottleneck. Egghatchability rates were low (70.6% per egg and 76.8% per pair), and hatchability increased after mate changes, suggesting inbreeding effects. Only an average of 34% of the population nested annually, which was well below the percentage of adults that should have reached an age of first breeding (41-56%). This chronic failure to nest appears to have been caused primarily by environmental and/or behavioral factors, and not by nest-site scarcity or a skewed sex ratio. Nest failure rates from nongenetic causes (i.e., predation, parasitism, and wet cavities) were low (29%) due to active management (protecting nests and fostering

  10. Laboratory colonisation and genetic bottlenecks in the tsetse fly Glossina pallidipes.

    Directory of Open Access Journals (Sweden)

    Marc Ciosi

    2014-02-01

    Full Text Available BACKGROUND: The IAEA colony is the only one available for mass rearing of Glossina pallidipes, a vector of human and animal African trypanosomiasis in eastern Africa. This colony is the source for Sterile Insect Technique (SIT programs in East Africa. The source population of this colony is unclear and its genetic diversity has not previously been evaluated and compared to field populations. METHODOLOGY/PRINCIPAL FINDINGS: We examined the genetic variation within and between the IAEA colony and its potential source populations in north Zimbabwe and the Kenya/Uganda border at 9 microsatellites loci to retrace the demographic history of the IAEA colony. We performed classical population genetics analyses and also combined historical and genetic data in a quantitative analysis using Approximate Bayesian Computation (ABC. There is no evidence of introgression from the north Zimbabwean population into the IAEA colony. Moreover, the ABC analyses revealed that the foundation and establishment of the colony was associated with a genetic bottleneck that has resulted in a loss of 35.7% of alleles and 54% of expected heterozygosity compared to its source population. Also, we show that tsetse control carried out in the 1990's is likely reduced the effective population size of the Kenya/Uganda border population. CONCLUSIONS/SIGNIFICANCE: All the analyses indicate that the area of origin of the IAEA colony is the Kenya/Uganda border and that a genetic bottleneck was associated with the foundation and establishment of the colony. Genetic diversity associated with traits that are important for SIT may potentially have been lost during this genetic bottleneck which could lead to a suboptimal competitiveness of the colony males in the field. The genetic diversity of the colony is lower than that of field populations and so, studies using colony flies should be interpreted with caution when drawing general conclusions about G. pallidipes biology.

  11. Bottleneck analysis and strategic planning using Tanahashi model for childhood diarrhea management in Gujarat, Western India.

    Science.gov (United States)

    Rupani, Mihir Prafulbhai; Gaonkar, Narayan T; Bhatt, Gneyaa S

    2016-10-01

    In spite of continued efforts, India is still lagging behind in achieving its MDG goals. The objectives of this study were to identify stake-holders who have a role to play in childhood diarrhea management, to identify gaps in childhood diarrhea management and to propose strategic options for relieving these gaps. Bottleneck analysis exercise was carried out based on the Tanahashi model in six High Priority Districts (HPDs) of Gujarat in period between July-November 2013. The major bottlenecks identified for Childhood Diarrhea management were poor demand generation, unsafe drinking water, poor access to improved sanitation facility and lack of equitable distribution and replenishment mechanisms for Oral Rehydration Solution (ORS) packets and Zinc tablets till the front-line worker level. The main strategic options that were suggested for relieving these bottlenecks were Zinc-ORS roll out in scale-up districts, develop Information Education Communication/Behaviour Change Communication (IEC/BCC) plan for childhood diarrhea management at state/district level, use of Drug Logistics Information Management System (DLIMS) software for supply chain management of Zinc-ORS, strengthening of chlorination activity at household level, monitoring implementation of Nirmal Bharat Abhiyaan (NBA) for constructing improved sanitation facilities at household level and to develop an IEC/BCC plan for hygiene promotion and usage of sanitary latrines. Use of Zinc tablets need to be intensified through an effective scale-up. Adequate demand generation activity is needed. There is need to address safe drinking water and improved sanitation measures at household levels. Multi-sectoral engagements and ownership of Zinc-ORS program is the need of the hour. PMID:27340871

  12. High and distinct range-edge genetic diversity despite local bottlenecks.

    Science.gov (United States)

    Assis, Jorge; Castilho Coelho, Nelson; Alberto, Filipe; Valero, Myriam; Raimondi, Pete; Reed, Dan; Serrão, Ester Alvares

    2013-01-01

    The genetic consequences of living on the edge of distributional ranges have been the subject of a largely unresolved debate. Populations occurring along persistent low latitude ranges (rear-edge) are expected to retain high and unique genetic diversity. In contrast, currently less favourable environmental conditions limiting population size at such range-edges may have caused genetic erosion that prevails over past historical effects, with potential consequences on reducing future adaptive capacity. The present study provides an empirical test of whether population declines towards a peripheral range might be reflected on decreasing diversity and increasing population isolation and differentiation. We compare population genetic differentiation and diversity with trends in abundance along a latitudinal gradient towards the peripheral distribution range of Saccorhiza polyschides, a large brown seaweed that is the main structural species of kelp forests in SW Europe. Signatures of recent bottleneck events were also evaluated to determine whether the recently recorded distributional shifts had a negative influence on effective population size. Our findings show decreasing population density and increasing spatial fragmentation and local extinctions towards the southern edge. Genetic data revealed two well supported groups with a central contact zone. As predicted, higher differentiation and signs of bottlenecks were found at the southern edge region. However, a decrease in genetic diversity associated with this pattern was not verified. Surprisingly, genetic diversity increased towards the edge despite bottlenecks and much lower densities, suggesting that extinctions and recolonizations have not strongly reduced diversity or that diversity might have been even higher there in the past, a process of shifting genetic baselines. PMID:23967038

  13. Bottle-neck type of neural network as a mapping device towards food specifications.

    Science.gov (United States)

    Novic, Marjana; Groselj, Neva

    2009-09-01

    A novel methodology is proposed for food specifications associated with the origin of food. The methodology was tested on honey samples collected within the TRACE EU project. The data were sampled in various regions in Europe and analysed for the trace elements content. The sampling sites were characterized by different geological origins, such as limestone, shale, or magmatic. We have chosen 14 elements, B, Na, Mg, A, K, Ca, Mn, Co, Ni, Cu, Zn, Rb, Sr, and Ba, due to their influence on the separation of samples regarding the geology of the sampling sites. A special architecture of an error back-propagation neural network, so called bottle-neck type of neural network was used to project the data into a 2D plane. The data were fed into the 14-nodes input layer and then transferred through the 2-nodes hidden layer (compared to a bottle-neck) to the 14-nodes output layer. The two hidden nodes representing the two coordinates of the projection plane enable us to map the samples used for training of the bottle-neck network. With the knowledge about the classes of individual samples we determine the clusters in the projection plane and consequently obtain the coordinates of the centroid (gravity point) of a particular cluster. The clusters are characterized with an ellipse shape borders spanning the length of up to 3sigma in each dimension. Since the data were classified as regard to the geology, three main clusters were sought: (i) limestone, (ii) shale/mudstone/clay/loess, and (iii) acid-magmatic origin of honey samples. The novel methodology proposed for food specifications was demonstrated on a reduced set of samples, which shows good clustering of all three classes in the projection plane, and on the third class of the original data set. PMID:19664464

  14. Direct structural mapping of organic field-effect transistors reveals bottlenecks to carrier transport

    KAUST Repository

    Li, Ruipeng

    2012-08-10

    X-ray microbeam scattering is used to map the microstructure of the organic semiconductor along the channel length of solution-processed bottom-contact OFET devices. Contact-induced nucleation is known to influence the crystallization behavior within the channel. We find that microstructural inhomogeneities in the center of the channel act as a bottleneck to charge transport. This problem can be overcome by controlling crystallization of the preferable texture, thus favoring more efficient charge transport throughout the channel. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Breaking CFD Bottlenecks in Gas-Turbine Flow-Path Design

    Science.gov (United States)

    Davis, Roger L.; Dannenhoffer, John F., III; Clark, John P.

    2010-01-01

    New ideas are forthcoming to break existing bottlenecks in using CFD during design. CAD-based automated grid generation. Multi-disciplinary use of embedded, overset grids to eliminate complex gridding problems. Use of time-averaged detached-eddy simulations as norm instead of "steady" RANS to include effects of self-excited unsteadiness. Combined GPU/Core parallel computing to provide over an order of magnitude increase in performance/price ratio. Gas-turbine applications are shown here but these ideas can be used for other Air Force, Navy, and NASA applications.

  16. A WEIGHTED INVERSE MINIMUM CUT PROBLEM UNDER THE BOTTLENECK TYPE HAMMING DISTANCE

    OpenAIRE

    LONGCHENG LIU; ENYU YAO

    2007-01-01

    An inverse optimization problem is defined as follows. Let S denote the set of feasible solutions of an optimization problem P, let c be a specified cost (capacity) vector, and x0 ∈ S. We want to perturb the cost (capacity) vector c to d so that x0 is an optimal solution of P with respect to the cost (capacity) vector d, and to minimize some objective function. In this paper, we consider the weighted inverse minimum cut problem under the bottleneck type Hamming distance. For the general case,...

  17. Phonon bottleneck in GaAs/AlxGa1−xAs quantum dots

    Directory of Open Access Journals (Sweden)

    Y. C. Chang

    2015-06-01

    Full Text Available We report low-temperature photoluminescence measurements on highly-uniform GaAs/AlxGa1−xAs quantum dots grown by droplet epitaxy. Recombination between confined electrons and holes bound to carbon acceptors in the dots allow us to determine the energies of the confined states in the system, as confirmed by effective mass calculations. The presence of acceptor-bound holes in the quantum dots gives rise to a striking observation of the phonon-bottleneck effect.

  18. Genetic diversity of native Turkish cattle breeds: Mantel, AMOVA and bottleneck analysis

    Directory of Open Access Journals (Sweden)

    Yusuf Özşensoy

    2014-09-01

    Full Text Available This study was conducted to evaluate potential extinction risk of Turkish native cattle breeds using Mantel and AMOVA tests and Bottleneck analysis. A total of 271 DNA samples were isolated from Anatolian Black, Anatolian Grey, South Anatolian Red, Native Southern Anatolian Yellow, East Anatolian Red, and Zavot cattle. In this study, genotypes of 20 microsatellites were determined by capillary electrophoresis and fragment analysis. A total of 269 different alleles were detected. The maximum and minimum numbers of total alleles were observed in TGLA122 (n=26 and INRA005 (n=7 loci, respectively. The highest average observed and expected heterozygosity values were determined as 0.619–0.852 and 0.669–0.877, respectively. The average FIS value was 0.068. Results of AMOVA and Mantel tests illustrated statistically significant differences in populations (p<0.001 and correlation (p<0.01. Bottleneck analysis revealed a normal distribution of L–shaped curve indicating that there was no recent risk of extinction for these breeds.

  19. Identification and Validation of Ifit1 as an Important Innate Immune Bottleneck

    Energy Technology Data Exchange (ETDEWEB)

    McDermott, Jason E.; Vartanian, Keri B.; Mitchell, Hugh D.; Stevens, S.L.; Sanfilippo, Antonio P.; Stenzel-Poore, Mary

    2012-06-20

    The innate immune system plays important roles in a number of disparate processes. Foremost, innate immunity is a first responder to invasion by pathogens and triggers early defensive responses and recruits the adaptive immune system. The innate immune system also responds to endogenous damage signals that arise from tissue injury. Recently it has been found that innate immunity plays an important role in neuroprotection against ischemic stroke through the activation of the primary innate immune receptors, Toll-like receptors (TLRs). Using several large-scale transcriptomic data sets from mouse and mouse macrophage studies we identified targets predicted to be important in controlling innate immune processes initiated by TLR activation. Targets were identified as genes with high betweenness centrality, so-called bottlenecks, in networks inferred from statistical associations between gene expression patterns. A small set of putative bottlenecks were identified in each of the data sets investigated including interferon-stimulated genes (Ifit1, Ifi47, Tgtp and Oasl2) as well as genes uncharacterized in immune responses (Axud1 and Ppp1r15a). We further validated one of these targets, Ifit1, in mouse macrophages by showing that silencing it suppresses induction of predicted downstream genes by lipopolysaccharide (LPS)-mediated TLR4 activation through an unknown direct or indirect mechanism. Our study demonstrates the utility of network analysis for identification of interesting targets related to innate immune function, and highlights that Ifit1 can exert a positive regulatory effect on downstream genes.

  20. The physics of empirical nuclei for spontaneous traffic breakdown in free flow at highway bottlenecks

    Science.gov (United States)

    Kerner, Boris S.; Koller, Micha; Klenov, Sergey L.; Rehborn, Hubert; Leibel, Michael

    2015-11-01

    Based on an empirical study of real field traffic data measured in 1996-2014 through road detectors installed on German freeways, we reveal physical features of empirical nuclei for spontaneous traffic breakdown in free flow at highway bottlenecks. A microscopic stochastic three-phase traffic model of the nucleation of spontaneous traffic breakdown presented in the article explains the empirical findings. It turns out that in the most cases a nucleus for the breakdown occurs through an interaction of one of waves in free flow with an empirical permanent speed disturbance localized at a highway bottleneck. The wave is a localized structure in free flow, in which the total flow rate is larger and the speed averaged across the highway is smaller than outside the wave. The waves in free flow appear due to oscillations in the percentage of slow vehicles; these waves propagate with the average speed of slow vehicles in free flow. Any of the empirical waves exhibits a two-dimensional asymmetric spatiotemporal structure: Wave's characteristics are different in different highway lanes.

  1. Note: Inhibiting bottleneck corrosion in electrical calcium tests for ultra-barrier measurements

    Energy Technology Data Exchange (ETDEWEB)

    Nehm, F., E-mail: frederik.nehm@iapp.de; Müller-Meskamp, L.; Klumbies, H.; Leo, K. [Institut für Angewandte Photophysik, Technische Universität Dresden, George-Bähr-Straße 1, 01069 Dresden (Germany)

    2015-12-15

    A major failure mechanism is identified in electrical calcium corrosion tests for quality assessment of high-end application moisture barriers. Accelerated calcium corrosion is found at the calcium/electrode junction, leading to an electrical bottleneck. This causes test failure not related to overall calcium loss. The likely cause is a difference in electrochemical potential between the aluminum electrodes and the calcium sensor, resulting in a corrosion element. As a solution, a thin, full-area copper layer is introduced below the calcium, shifting the corrosion element to the calcium/copper junction and inhibiting bottleneck degradation. Using the copper layer improves the level of sensitivity for the water vapor transmission rate (WVTR) by over one order of magnitude. Thin-film encapsulated samples with 20 nm of atomic layer deposited alumina barriers this way exhibit WVTRs of 6 × 10{sup −5} g(H{sub 2}O)/m{sup 2}/d at 38 °C, 90% relative humidity.

  2. [Bottlenecks in the provision of inpatient care--caused by the Hospital Funding Act].

    Science.gov (United States)

    Jansen, Christoph

    2010-01-01

    The responsibility of the state for ensuring the provision of hospital care services to its citizens derives from the welfare state principle laid down in Sect. 20 para. 1 GG (Grundgesetz, i.e., the German constitutional law). The state fulfils this responsibility by means of planning and funding regulations in the Hospital Funding Act (KHG), the Hospital Remuneration Act (KHEntG), the National Ordinance on Hospital Rates (BPflV), the Hospital Laws of the German federal states and other supplementary legislation. The funding of hospitals is based on a dual funding system, meaning that hospital investment costs generally need to be borne by the German federal states as required, while operating costs will have to be funded through the remuneration for hospital treatments. Because of the tight budget situation of the German federal states a considerable backlog of investment has built up. After a transition period (between 2005 and 2009) operating costs are now funded on the basis of the so-called DRG system (DRG=Diagnosis Related Groups)--irrespective of the actual costs incurred by each individual hospital, which has led to a commodification of hospital care services. Whether this commodification avoids bottlenecks in the provision of health services to hospital patients or creates additional bottlenecks, is a controversial issue. PMID:20870488

  3. Topological-based bottleneck analysis and improvement strategies for traffic networks

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A method is proposed to find key components of traffic networks with homogenous and heterogeneous topologies, in which heavier traffic flow is transported. One component, called the skeleton, is the minimum spanning tree (MST) based on the zero flow cost (ZCMST). The other component is the infinite incipient percolation cluster (IIC) which represents the spine of the traffic network. Then, a new method to analysis the property of the bottleneck in a large scale traffic network is given from a macroscopic and statistical viewpoint. Moreover, three effective strategies are proposed to alleviate traffic congestion. The significance of the findings is that one can significantly improve the global transport by enhancing the capacity in the ZCMST with a few links, while for improving the local traffic property, improving a tiny fraction of the traffic network in the IIC is effective. The result can be used to help traffic managers prevent and alleviate traffic congestion in time, guard against the formation of congestion bottleneck, and make appropriate policies for traffic demand management. Meanwhile, the method has very important theoretical significance and practical worthiness in optimizing traffic organization, traffic control, and disposal of emergency.

  4. Optimal design of future electricity supply systems. An analysis of potential bottlenecks in NW-Europe

    International Nuclear Information System (INIS)

    This paper analyses the potential bottlenecks that might emerge in the North-western European electricity supply system as a result of a number of (autonomous) long-term developments. The main long-term developments we identify are 1) a continuing increase in the demand for electricity, 2) a gradual shift from conventional electricity generation towards unconventional (green) generation, 3) a gradual shift from centralized generation towards decentralized generation and 4) a shift from national self-sufficient electricity supply systems towards a pan-European electricity system. Although it has been recognized that these developments might cause certain problems in some or more elements of the electricity supply chain, a coherent and comprehensive framework for the identification of these problems is lacking. More specific, governments and regulators seem to focus on certain parts of the electricity supply system separately, whereas certain interdependencies in the system have received relatively little attention. This paper presents such a framework and identifies some potential bottlenecks that receive relatively little attention from policy makers. These are 1) the increasing penetration of distributed generation, 2) an increasingly important role for demand response and 3) the lack of locational signals in the electricity supply system. The potential role of governments and markets in these issues is briefly explored. (Author)

  5. Characteristics of forensic imaging performance--an analysis of forensic imaging bottlenecks.

    Science.gov (United States)

    Branigan, Steven

    2013-05-01

    Disk imaging involves copying all of the data from a source disk drive to a target. Typically, the target for the copy is another disk drive. Forensic processes developed years ago do not appear to be adequate for current storage technology. For example, with disk drive capacities now exceeding 1 Terabyte, a typical disk imaging can take over 8 hours at typical rates. With disk drive capacities increasing, forensic copying is expected to take even longer. Along with increase in disk capacity, the industry has also seen an increase in data transfer rates. In many cases, forensic imaging is taking longer than necessary. To identify the bottlenecks, an examination of different methods used to transfer data from a source disk was performed. Factors considered were differing disk access technologies. One finding is that the USB disk access technology (version 2.0 and earlier) is a significant bottleneck for data transfer rates, especially when the USB device is a write-blocker. Other factors that contribute to the efficiency of a forensic copy are the file system used to write a forensic image and the data transfer size used when reading from a disk drive. Optimal parameters for performing a forensic acquisition from a disk drive are identified. PMID:23458238

  6. Flagella-Driven Flows Circumvent Diffusive Bottlenecks that Inhibit Metabolite Exchange

    Science.gov (United States)

    Short, Martin; Solari, Cristian; Ganguly, Sujoy; Kessler, John; Goldstein, Raymond; Powers, Thomas

    2006-03-01

    The evolution of single cells to large and multicellular organisms requires matching the organisms' needs to the rate of exchange of metabolites with the environment. This logistic problem can be a severe constraint on development. For organisms with a body plan that approximates a spherical shell, such as colonies of the volvocine green algae, the required current of metabolites grows quadratically with colony radius whereas the rate at which diffusion can exchange metabolites grows only linearly with radius. Hence, there is a bottleneck radius beyond which the diffusive current cannot keep up with metabolic demands. Using Volvox carteri as a model organism, we examine experimentally and theoretically the role that advection of fluid by surface-mounted flagella plays in enhancing nutrient uptake. We show that fluid flow driven by the coordinated beating of flagella produces a convective boundary layer in the concentration of a diffusing solute which in turn renders the metabolite exchange rate quadratic in the colony radius. This enhanced transport circumvents the diffusive bottleneck, allowing increase in size and thus evolutionary transitions to multicellularity in the Volvocales.

  7. Asymmetric effect of route-length difference and bottleneck on route choice in two-route traffic system

    Science.gov (United States)

    Hino, Yuki; Nagatani, Takashi

    2015-06-01

    We study the traffic behavior in the asymmetric two-route traffic system with real-time information. In the asymmetric two-route system, the length on route A is different from that on route B and there exists a bottleneck on route A. We extend the symmetric two-route dynamic model to the asymmetric case. We investigate the asymmetric effects of the route-length difference and bottleneck on the route choice with real-time information. The travel time on each route depends on the road length, bottleneck, and vehicular density. We derive the dependence of the travel time and mean density on the route-length ratio. We show where, when, and how the congestion occurs by the route choice in the asymmetric two-route system. We clarify the effect of the route-length ratio on the traffic behavior in the route choice.

  8. Country planning bottlenecks for the Integral Program Wind power (IPW) projects and the importance of knowledge transfer

    International Nuclear Information System (INIS)

    Most bottlenecks in realizing the aims of the Dutch title project concern problems with the site selection and administrative or juridical problems. The attitude of municipalities towards wind turbines is reserved, their policies not uniform, and the possibility to participate in the licensing procedures has been frequently used. If the energy policy of the Dutch government to produce 1000 MW in the year 2000 should be realized, initiatives must be developed to clear these planning bottlenecks. Some propositions are made with regard to government standards for noise pollution, safety, nature values, agreements with dike managers, regulations for land acquisition, transfer of information, and a manual for municipalities. 2 figs., 5 refs

  9. Quantification of bottlenecks to fast charging of lithium-ion-insertion cells for electric vehicles

    Science.gov (United States)

    Chandrasekaran, Rajeswari

    2014-12-01

    In this work, an isothermal, physics-based, dual lithium-ion insertion cell sandwich model is used for simulating the galvanostatic charge performance of a graphite (LixC6)/liquid electrolyte/Liy(NiaCobMnc)O2 at room temperature at various current densities. The modeling results are compared with experimental cell potential vs. capacity data. The validated model is used to identify the bottlenecks to fast charging by quantification of the various contributions to the cell overpotential. Lithium plating at the negative electrode is shown to be thermodynamically feasible during galvanostatic charging at 2C rate and above. This work will aid in research and development activities to overcome the hurdles to fast charging of advance electric vehicle batteries.

  10. Algorithm Based on Taboo Search and Shifting Bottleneck for Job Shop Scheduling

    Institute of Scientific and Technical Information of China (English)

    Wen-Qi Huang; Zhi Huang

    2004-01-01

    In this paper, a computational effective heuristic method for solving the minimum makespan problem of job shop scheduling is presented. It is based on taboo search procedure and on the shifting bottleneck procedure used to jump out of the trap of the taboo search procedure. A key point of the algorithm is that in the taboo search procedure two taboo lists are used to forbid two kinds of reversals of arcs, which is a new and effective way in taboo search methods for job shop scheduling. Computational experiments on a set of benchmark problem instances show that, in several cases, the approach, in reasonable time, yields better solutions than the other heuristic procedures discussed in the literature.

  11. Engineering oilseeds for sustainable production of industrial and nutritional feedstocks: solving bottlenecks in fatty acid flux.

    Science.gov (United States)

    Cahoon, Edgar B; Shockey, Jay M; Dietrich, Charles R; Gidda, Satinder K; Mullen, Robert T; Dyer, John M

    2007-06-01

    Oilseeds provide a unique platform for the production of high-value fatty acids that can replace non-sustainable petroleum and oceanic sources of specialty chemicals and aquaculture feed. However, recent efforts to engineer the seeds of crop and model plant species to produce new types of fatty acids, including hydroxy and conjugated fatty acids for industrial uses and long-chain omega-3 polyunsaturated fatty acids for farmed fish feed, have met with only modest success. The collective results from these studies point to metabolic 'bottlenecks' in the engineered plant seeds that substantially limit the efficient or selective flux of unusual fatty acids between different substrate pools and ultimately into storage triacylglycerol. Evidence is emerging that diacylglycerol acyltransferase 2, which catalyzes the final step in triacylglycerol assembly, is an important contributor to the synthesis of unusual fatty acid-containing oils, and is likely to be a key target for future oilseed metabolic engineering efforts. PMID:17434788

  12. Metabolic engineering of yeast to produce fatty acid-derived biofuels: bottlenecks and solutions.

    Science.gov (United States)

    Sheng, Jiayuan; Feng, Xueyang

    2015-01-01

    Fatty acid-derived biofuels can be a better solution than bioethanol to replace petroleum fuel, since they have similar energy content and combustion properties as current transportation fuels. The environmentally friendly microbial fermentation process has been used to synthesize advanced biofuels from renewable feedstock. Due to their robustness as well as the high tolerance to fermentation inhibitors and phage contamination, yeast strains such as Saccharomyces cerevisiae and Yarrowia lipolytica have attracted tremendous attention in recent studies regarding the production of fatty acid-derived biofuels, including fatty acids, fatty acid ethyl esters, fatty alcohols, and fatty alkanes. However, the native yeast strains cannot produce fatty acids and fatty acid-derived biofuels in large quantities. To this end, we have summarized recent publications in this review on metabolic engineering of yeast strains to improve the production of fatty acid-derived biofuels, identified the bottlenecks that limit the productivity of biofuels, and categorized the appropriate approaches to overcome these obstacles. PMID:26106371

  13. Piecewise Function Feedback Strategy in Intelligent Traffic Systems with a Speed Limit Bottleneck

    Science.gov (United States)

    Chen, Bokui; Sun, Xiaoyan; Wei, Hua; Dong, Chuanfei; Wang, Binghong

    The road capacity can be greatly improved if an appropriate and effective information feedback strategy is adopted in the traffic system. In this paper, a strategy called piecewise function feedback strategy (PFFS) is introduced and applied into an asymmetrical two-route scenario with a speed limit bottleneck in which the dynamic information can be generated and displayed on the information board to guide road users to make a choice. Meanwhile, the velocity-dependent randomization (VDR) mechanism is adopted which can better reflect the dynamic behavior of vehicles in the system than NS mechanism. Simulation results adopting PFFS have demonstrated high efficiency in controlling spatial distribution of traffic patterns compared with the previous strategies.

  14. Phonon bottleneck in p-type Ge/Si quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Yakimov, A. I., E-mail: yakimov@isp.nsc.ru [Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Science, 630090 Novosibirsk (Russian Federation); Tomsk State University, 634050 Tomsk (Russian Federation); Kirienko, V. V.; Armbrister, V. A. [Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Science, 630090 Novosibirsk (Russian Federation); Bloshkin, A. A.; Dvurechenskii, A. V. [Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Science, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 630090 Novosibirsk (Russian Federation)

    2015-11-23

    We study the effect of quantum dot size on the mid-infrared photo- and dark current, photoconductive gain, and hole capture probability in ten-period p-type Ge/Si quantum dot heterostructures. The dot dimensions are varied by changing the Ge coverage and the growth temperature during molecular beam epitaxy of Ge/Si(001) system in the Stranski-Krastanov growth mode. In all samples, we observed the general tendency: with decreasing the size of the dots, the dark current and hole capture probability are reduced, while the photoconductive gain and photoresponse are enhanced. Suppression of the hole capture probability in small-sized quantum dots is attributed to a quenched electron-phonon scattering due to phonon bottleneck.

  15. Population structure and genetic bottleneck in sweet cherry estimated with SSRs and the gametophytic self-incompatibility locus

    Directory of Open Access Journals (Sweden)

    Mariette Stéphanie

    2010-08-01

    Full Text Available Abstract Background Domestication and breeding involve the selection of particular phenotypes, limiting the genomic diversity of the population and creating a bottleneck. These effects can be precisely estimated when the location of domestication is established. Few analyses have focused on understanding the genetic consequences of domestication and breeding in fruit trees. In this study, we aimed to analyse genetic structure and changes in the diversity in sweet cherry Prunus avium L. Results Three subgroups were detected in sweet cherry, with one group of landraces genetically very close to the analysed wild cherry population. A limited number of SSR markers displayed deviations from the frequencies expected under neutrality. After the removal of these markers from the analysis, a very limited bottleneck was detected between wild cherries and sweet cherry landraces, with a much more pronounced bottleneck between sweet cherry landraces and modern sweet cherry varieties. The loss of diversity between wild cherries and sweet cherry landraces at the S-locus was more significant than that for microsatellites. Particularly high levels of differentiation were observed for some S-alleles. Conclusions Several domestication events may have happened in sweet cherry or/and intense gene flow from local wild cherry was probably maintained along the evolutionary history of the species. A marked bottleneck due to breeding was detected, with all markers, in the modern sweet cherry gene pool. The microsatellites did not detect the bottleneck due to domestication in the analysed sample. The vegetative propagation specific to some fruit trees may account for the differences in diversity observed at the S-locus. Our study provides insights into domestication events of cherry, however, requires confirmation on a larger sampling scheme for both sweet cherry landraces and wild cherry.

  16. To an optimal electricity supply system. Possible bottlenecks in the development to an optimal electricity supply system in northwest Europe

    International Nuclear Information System (INIS)

    It is uncertain how the electricity system in Europe, and in particular northwest Europe and the Netherlands, will develop in the next fifteen years. The main objective of this report is to identify possible bottlenecks that may hamper the northwest European electricity system to develop into an optimal system in the long term (until 2020). Subsequently, based on the identified bottlenecks, the report attempts to indicate relevant market response and policy options. To be able to identify possible bottlenecks in the development to an optimal electricity system, an analytical framework has been set up with the aim to identify possible (future) problems in a structured way. The segments generation, network, demand, balancing, and policy and regulation are analysed, as well as the interactions between these segments. Each identified bottleneck is assessed on the criteria reliability, sustainability and affordability. Three bottlenecks are analysed in more detail: (1) The increasing penetration of distributed generation (DG) and its interaction with the electricity network. Dutch policy could be aimed at: (a) Gaining more insight in the costs and benefits that result from the increasing penetration of DG; (b) Creating possibilities for DSOs to experiment with innovative (network management) concepts; (c) Introducing locational signals; and (d) Further analyse the possibility of ownership unbundling; (2) The problem of intermittency and its implications for balancing the electricity system. Dutch policy could be aimed at: (a) Creating the environment in which the market is able to respond in an efficient way; (b) Monitoring market responses; (c) Market coupling; and (d) Discussing the timing of the gate closure; and (3) Interconnection and congestion issues in combination with generation. Dutch policy could be aimed at: (a) Using the existing interconnection capacity as efficient as possible; (b) Identifying the causes behind price differences; and (c) Harmonise market

  17. Genetic architecture and bottleneck analyses of Salem Black goat breed based on microsatellite markers

    Directory of Open Access Journals (Sweden)

    A. K. Thiruvenkadan

    2014-09-01

    Full Text Available Aim: The present study was undertaken in Salem Black goat population for genetic analysis at molecular level to exploit the breed for planning sustainable improvement, conservation and utilization, which subsequently can improve the livelihood of its stakeholders. Materials and Methods: Genomic DNA was isolated from blood samples of 50 unrelated Salem Black goats with typical phenotypic features in several villages in the breeding tract and the genetic characterization and bottleneck analysis in Salem Black goat was done using 25 microsatellite markers as recommended by the Food and Agricultural Organization, Rome, Italy. The basic measures of genetic variation were computed using bioinformatic software. To evaluate the Salem Black goats for mutation drift equilibrium, three tests were performed under three different mutation models, viz., infinite allele model (IAM, stepwise mutation model (SMM and two-phase model (TPM and the observed gene diversity (He and expected equilibrium gene diversity (Heq were estimated under different models of microsatellite evolution. Results: The study revealed that the observed number of alleles ranged from 4 (ETH10, ILSTS008 to 17 (BM64444 with a total of 213 alleles and mean of 10.14±0.83 alleles across loci. The overall observed heterozygosity, expected heterozygosity, inbreeding estimate and polymorphism information content values were 0.631±0.041, 0.820±0.024, 0.233±0.044 and 0.786±0.023 respectively indicating high genetic diversity. The average observed gene diversities (He pooled over different markers was 0.829±0.024 and the average expected gene diversities under IAM, TPM and SMM models were 0.769±0.026, 0.808±0.024 and 0.837±0.020 respectively. The number of loci found to exhibit gene diversity excess under IAM, TPM and SMM models were 18, 17 and 12 respectively. Conclusion: All the three statistical tests, viz., sign test, standardized differences test and Wilcoxon sign rank test, revealed

  18. Smart-pixel-based free-space interconnects: solving the high-speed multichip packaging bottleneck

    Science.gov (United States)

    Haney, Michael W.; Christensen, Marc P.; Milojkovic, Predrag; McFadden, Michael J.

    2001-11-01

    As IC densities grow to 100's of millions of devices per chip and beyond, the inter-chip link bandwidth becomes a critical performance-limiting bottleneck in many applications. Electronic packaging technology has not kept pace with the growth of IC I/O requirements. Recent advances in smart pixel technology, however, offer the potential to use 3-D optical interconnects to overcome the inter-chip I/O bottleneck by linking dense arrays of Vertical Cavity Surface Emitting Lasers (VCSELs) and photodetectors, which are directly integrated onto electronic IC circuits. Many switching and parallel computing applications demand multi-chip interconnection fabrics that achieve high-density global I/O across an array of chips. Such global interconnections require a high degree of space-variance in the interconnection fabric, in addition to high inter-chip throughput capacity. This paper reviews the architectural and optical design issues associated with global interconnections among arrays of chips. The emphasis is on progress made in the design and implementation of the second generation Free-space Accelerator for Switching Terabit Networks (FAST-Net) prototype. The FAST-Net prototype uses a macro-optical lens array and mirror to effect a global (fully connected) fabric across a 4 X 4 array of smart pixel chips. Clusters of VCSELs and photodetectors are imaged onto corresponding clusters on other chips, creating a high- density bi-directional data path between every pair of smart pixel chips on a multi-chip module. The combination of programmable intra-chip electronic routing and the fixed global inter-chip optical interconnection pattern of the FAST- Net architecture has been shown to provide a low latency, minimum complexity fabric, that can effect an arbitrary interconnection pattern across the chip array. Recent experimental results show that the narrow beam characteristics of VCSELs can be exploited in an efficient optical design for the FAST-Net optical interconnection

  19. Photodegradation alleviates the lignin bottleneck for carbon turnover in terrestrial ecosystems.

    Science.gov (United States)

    Austin, Amy T; Méndez, M Soledad; Ballaré, Carlos L

    2016-04-19

    A mechanistic understanding of the controls on carbon storage and losses is essential for our capacity to predict and mitigate human impacts on the global carbon cycle. Plant litter decomposition is an important first step for carbon and nutrient turnover, and litter inputs and losses are essential in determining soil organic matter pools and the carbon balance in terrestrial ecosystems. Photodegradation, the photochemical mineralization of organic matter, has been recently identified as a mechanism for previously unexplained high rates of litter mass loss in arid lands; however, the global significance of this process as a control on carbon cycling in terrestrial ecosystems is not known. Here we show that, across a wide range of plant species, photodegradation enhanced subsequent biotic degradation of leaf litter. Moreover, we demonstrate that the mechanism for this enhancement involves increased accessibility to plant litter carbohydrates for microbial enzymes. Photodegradation of plant litter, driven by UV radiation, and especially visible (blue-green) light, reduced the structural and chemical bottleneck imposed by lignin in secondary cell walls. In leaf litter from woody species, specific interactions with UV radiation obscured facilitative effects of solar radiation on biotic decomposition. The generalized effect of sunlight exposure on subsequent microbial activity, mediated by increased accessibility to cell wall polysaccharides, suggests that photodegradation is quantitatively important in determining rates of mass loss, nutrient release, and the carbon balance in a broad range of terrestrial ecosystems. PMID:27044070

  20. Metabolic Engineering of Yeast to Produce Fatty Acid-derived Biofuels: Bottlenecks and Solutions

    Directory of Open Access Journals (Sweden)

    Jiayuan eSheng

    2015-06-01

    Full Text Available Fatty acid-derived biofuels can be a better solution than bioethanol to replace petroleum fuel, since they have similar energy content and combustion properties as current transportation fuels. The environmentally friendly microbial fermentation process has been used to synthesize advanced biofuels from renewable feedstock. Due to their robustness as well as the high tolerance to fermentation inhibitors and phage contamination, yeast strains such as Saccharomyces cerevisiae and Yarrowia lipolytica have attracted tremendous attention in recent studies regarding the production of fatty acid-derived biofuels, including fatty acids, fatty acid ethyl esters, fatty alcohols, and fatty alkanes. However, the native yeast strains cannot produce fatty acids and fatty acid-derived biofuels in large quantities. To this end, we have summarized recent publications in this review on metabolic engineering of yeast strains to improve the production of fatty acid-derived biofuels, identified the bottlenecks that limit the productivity of biofuels, and categorized the appropriate approaches to overcome these obstacles.

  1. Development and bottlenecks of renewable electricity generation in China: a critical review.

    Science.gov (United States)

    Hu, Yuanan; Cheng, Hefa

    2013-04-01

    This review provides an overview on the development and status of electricity generation from renewable energy sources, namely hydropower, wind power, solar power, biomass energy, and geothermal energy, and discusses the technology, policy, and finance bottlenecks limiting growth of the renewable energy industry in China. Renewable energy, dominated by hydropower, currently accounts for more than 25% of the total electricity generation capacity. China is the world's largest generator of both hydropower and wind power, and also the largest manufacturer and exporter of photovoltaic cells. Electricity production from solar and biomass energy is at the early stages of development in China, while geothermal power generation has received little attention recently. The spatial mismatch in renewable energy supply and electricity demand requires construction of long-distance transmission networks, while the intermittence of renewable energy poses significant technical problems for feeding the generated electricity into the power grid. Besides greater investment in research and technology development, effective policies and financial measures should also be developed and improved to better support the healthy and sustained growth of renewable electricity generation. Meanwhile, attention should be paid to the potential impacts on the local environment from renewable energy development, despite the wider benefits for climate change. PMID:23445126

  2. Policy redesign for solving the financial bottleneck in demand side management (DSM) in China

    International Nuclear Information System (INIS)

    DSM is one of the best and most practical policy tools for China to balance environmental protection and economic growth. However, the bottleneck lies in the lack of long-term, stable, sufficient and gradually increasing funds to flow into DSM projects. The author redesigns the practical 'system benefit charge (SBC)' policy, which will provide long-term and stable funding for DSM, the policy to facilitate the financial support from banking sector and capital market, and investigates the possibility of DSM funding from CDM projects. SBC is the best way to boost long-term stable and sufficient funding for DSM at present in China. The current low inflation rate and natural resource price are favored to expedite the implementation of SBC and DSM developments. With regard to the uneven development, China needs to design relative policies to offset the impact in different areas, such as tax reduction and fiscal subsides. It is time for China to develop a definite and clear target and timetable to implement DSM, which will give the public and enterprises a definite and clear expectation for the future. The government should publicize a clear and integrated DSM development plan and relative policy outline in the near, medium, and long term. (author)

  3. Fluctuating bottleneck model studies on kinetics of DNA escape from α-hemolysin nanopores.

    Science.gov (United States)

    Bian, Yukun; Wang, Zilin; Chen, Anpu; Zhao, Nanrong

    2015-11-14

    We have proposed a fluctuation bottleneck (FB) model to investigate the non-exponential kinetics of DNA escape from nanometer-scale pores. The basic idea is that the escape rate is proportional to the fluctuating cross-sectional area of DNA escape channel, the radius r of which undergoes a subdiffusion dynamics subjected to fractional Gaussian noise with power-law memory kernel. Such a FB model facilitates us to obtain the analytical result of the averaged survival probability as a function of time, which can be directly compared to experimental results. Particularly, we have applied our theory to address the escape kinetics of DNA through α-hemolysin nanopores. We find that our theoretical framework can reproduce the experimental results very well in the whole time range with quite reasonable estimation for the intrinsic parameters of the kinetics processes. We believe that FB model has caught some key features regarding the long time kinetics of DNA escape through a nanopore and it might provide a sound starting point to study much wider problems involving anomalous dynamics in confined fluctuating channels. PMID:26567685

  4. End-Devonian extinction and a bottleneck in the early evolution of modern jawed vertebrates.

    Science.gov (United States)

    Sallan, Lauren Cole; Coates, Michael I

    2010-06-01

    The Devonian marks a critical stage in the early evolution of vertebrates: It opens with an unprecedented diversity of fishes and closes with the earliest evidence of limbed tetrapods. However, the latter part of the Devonian has also been characterized as a period of global biotic crisis marked by two large extinction pulses: a "Big Five" mass extinction event at the Frasnian-Famennian stage boundary (374 Ma) and the less well-documented Hangenberg event some 15 million years later at the Devonian-Carboniferous boundary (359 Ma). Here, we report the results of a wide-ranging analysis of the impact of these events on early vertebrate evolution, which was obtained from a database of vertebrate occurrences sampling over 1,250 taxa from 66 localities spanning Givetian to Serpukhovian stages (391 to 318 Ma). We show that major vertebrate clades suffered acute and systematic effects centered on the Hangenberg extinction involving long-term losses of over 50% of diversity and the restructuring of vertebrate ecosystems worldwide. Marine and nonmarine faunas were equally affected, precluding the existence of environmental refugia. The subsequent recovery of previously diverse groups (including placoderms, sarcopterygian fish, and acanthodians) was minimal. Tetrapods, actinopterygians, and chondrichthyans, all scarce within the Devonian, undergo large diversification events in the aftermath of the extinction, dominating all subsequent faunas. The Hangenberg event represents a previously unrecognized bottleneck in the evolutionary history of vertebrates as a whole and a historical contingency that shaped the roots of modern biodiversity. PMID:20479258

  5. Neutron capture cross section of $^{90}$Zr Bottleneck in the s-process reaction flow

    CERN Document Server

    Tagliente, G; Milazzo, P M; Moreau, C; Aerts, G; Abbondanno, U; Alvarez, H; Alvarez-Velarde, F; Andriamonje, Samuel A; Andrzejewski, J; Assimakopoulos, Panayiotis; Audouin, L; Badurek, G; Baumann, P; Bečvář, F; Berthoumieux, E; Bisterzo, S; Calviño, F; Calviani, M; Cano-Ott, D; Capote, R; Carrapiço, C; Cennini, P; Chepel, V; Chiaveri, Enrico; Colonna, N; Cortés, G; Couture, A; Cox, J; Dahlfors, M; David, S; Dillman, I; Domingo-Pardo, C; Dridi, W; Durán, I; Eleftheriadis, C; Embid-Segura, M; Ferrant, L; Ferrari, A; Ferreira-Marques, R; Furman, W; Gallino, R; Gonçalves, I; Gonzalez-Romero, E; Gramegna, F; Guerrero, C; Gunsing, F; Haas, B; Haight, R; Heil, M; Herrera-Martínez, A; Igashira, M; Jericha, E; Käppeler, F; Kadi, Y; Karadimos, D; Karamanis, D; Kerveno, M; Köhler, P; Kossionides, E; Krtička, M; Lamboudis, C; Leeb, H; Lindote, A; Lopes, I; Lozano, M; Lukic, S; Marganiec, J; Marrone, S; Martínez, T; Massimi, C; Mastinu, P; Mengoni, A; Mosconi, M; Neves, F; Oberhummer, Heinz; O'Brien, S; Pancin, J; Papachristodoulou, C; Papadopoulos, C; Paradela, C; Patronis, N; Pavlik, A; Pavlopoulos, P; Perrot, L; Pigni, M T; Plag, R; Plompen, A; Plukis, A; Poch, A; Praena, J; Pretel, C; Quesada, J; Rauscher, T; Reifarth, R; Rubbia, Carlo; Rudolf, G; Rullhusen, P; Salgado, J; Santos, J; Sarchiapone, L; Savvidis, I; Stéphan, C; Taín, J L; Tassan-Got, L; Tavora, L; Terlizzi, R; Vannini, G; Vaz, P; Ventura, A; Villamarín, D; Vincente, M, C; Vlachoudis, V; Vlastou, R; Voss, F; Walter, S; Wendler, H; Wiescher, M; Wisshak, K

    2008-01-01

    The neutron capture cross sections of the Zr isotopes have important implications in nuclear astrophysics and for reactor design. The small cross section of the neutron magic nucleus 90Zr, which accounts for more than 50% of natural zirconium represents one of the key isotopes for the stellar s-process, because it acts as a bottleneck in the neutron capture chain between the Fe seed and the heavier isotopes. The same element, Zr, also is an important component of the structural materials used in traditional and advanced nuclear reactors. The (n,γ) cross section has been measured at CERN, using the n_TOF spallation neutron source. In total, 45 resonances could be resolved in the neutron energy range below 70 keV, 10 being observed for the first time thanks to the high resolution and low backgrounds at n_TOF. On average, the Γγ widths obtained in resonance analyses with the R-matrix code SAMMY were 15% smaller than reported previously. By these results, the accuracy of the Maxwellian averaged cross section f...

  6. Observation of a hot-phonon bottleneck in lead-iodide perovskites

    Science.gov (United States)

    Yang, Ye; Ostrowski, David P.; France, Ryan M.; Zhu, Kai; van de Lagemaat, Jao; Luther, Joseph M.; Beard, Matthew C.

    2016-01-01

    We study the carrier dynamics in planar methyl ammonium lead iodide perovskite films using broadband transient absorption spectroscopy. We show that the sharp optical absorption onset is due to an exciton transition that is inhomogeneously broadened with a binding energy of 9 meV. We fully characterize the transient absorption spectrum by free-carrier-induced bleaching of the exciton transition, quasi-Fermi energy, carrier temperature and bandgap renormalization constant. The photo-induced carrier temperature is extracted from the transient absorption spectra and monitored as a function of delay time for different excitation wavelengths and photon fluences. We find an efficient hot-phonon bottleneck that slows down cooling of hot carriers by three to four orders of magnitude in time above a critical injection carrier density of ˜5 × 1017 cm-3. Compared with molecular beam epitaxially grown GaAs, the critical density is an order of magnitude lower and the relaxation time is approximately three orders of magnitude longer.

  7. Regular bottlenecks and restrictions to somatic fusion prevent the accumulation of mitochondrial defects in Neurospora.

    Science.gov (United States)

    Bastiaans, E; Aanen, D K; Debets, A J M; Hoekstra, R F; Lestrade, B; Maas, M F P M

    2014-07-01

    The replication and segregation of multi-copy mitochondrial DNA (mtDNA) are not under strict control of the nuclear DNA. Within-cell selection may thus favour variants with an intracellular selective advantage but a detrimental effect on cell fitness. High relatedness among the mtDNA variants of an individual is predicted to disfavour such deleterious selfish genetic elements, but experimental evidence for this hypothesis is scarce. We studied the effect of mtDNA relatedness on the opportunities for suppressive mtDNA variants in the fungus Neurospora carrying the mitochondrial mutator plasmid pKALILO. During growth, this plasmid integrates into the mitochondrial genome, generating suppressive mtDNA variants. These mtDNA variants gradually replace the wild-type mtDNA, ultimately culminating in growth arrest and death. We show that regular sequestration of mtDNA variation is required for effective selection against suppressive mtDNA variants. First, bottlenecks in the number of mtDNA copies from which a 'Kalilo' culture started significantly increased the maximum lifespan and variation in lifespan among cultures. Second, restrictions to somatic fusion among fungal individuals, either by using anastomosis-deficient mutants or by generating allotype diversity, prevented the accumulation of suppressive mtDNA variants. We discuss the implications of these results for the somatic accumulation of mitochondrial defects during ageing. PMID:24864316

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

    Science.gov (United States)

    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

  9. Fluctuating bottleneck model studies on kinetics of DNA escape from α-hemolysin nanopores

    Science.gov (United States)

    Bian, Yukun; Wang, Zilin; Chen, Anpu; Zhao, Nanrong

    2015-11-01

    We have proposed a fluctuation bottleneck (FB) model to investigate the non-exponential kinetics of DNA escape from nanometer-scale pores. The basic idea is that the escape rate is proportional to the fluctuating cross-sectional area of DNA escape channel, the radius r of which undergoes a subdiffusion dynamics subjected to fractional Gaussian noise with power-law memory kernel. Such a FB model facilitates us to obtain the analytical result of the averaged survival probability as a function of time, which can be directly compared to experimental results. Particularly, we have applied our theory to address the escape kinetics of DNA through α-hemolysin nanopores. We find that our theoretical framework can reproduce the experimental results very well in the whole time range with quite reasonable estimation for the intrinsic parameters of the kinetics processes. We believe that FB model has caught some key features regarding the long time kinetics of DNA escape through a nanopore and it might provide a sound starting point to study much wider problems involving anomalous dynamics in confined fluctuating channels.

  10. A New Wireless Packet Scheduling Algorithm Based on EDF and Its Application in Multi-bottleneck Networks

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Most of current wireless packet scheduling algorithms aim at resource allocation as fairly as possible or maximizing throughput. This paper proposed a new packet scheduling algorithm that aims at satisfying delay requirement and is the improvement of earliest due first (EDF) algorithm in wired networks. The main idea is to classify the packets based on their delay bound, scheduling the most "urgent" class of user and the users that have the best channel condition with higher priority. This algorithm can easily integrate with common buffer management algorithms, when buffer management algorithm cannot accept new arrival packets, try to modify scheduling policy. Packet scheduling algorithms in multiple bottleneck wireless networks were also discussed. A new variable multi-hop factor was defined to estimate the congestion situation (including channel condition) of future hops.Multi-hop factor can be integrated into packet scheduling algorithms as assistant and supplement to improve its performance in multi-bottleneck wireless networks.

  11. Are all intertidal wetlands naturally created equal? Bottlenecks, thresholds and knowledge gaps to mangrove and saltmarsh ecosystems

    Science.gov (United States)

    Friess, Daniel A.; Krauss, Ken W.; Horstman, Erik M.; Balke, Thorsten; Bouma, Tjeerd J.; Galli, Demis; Webb, Edward L.

    2011-01-01

    Intertidal wetlands such as saltmarshes and mangroves provide numerous important ecological functions, though they are in rapid and global decline. To better conserve and restore these wetland ecosystems, we need an understanding of the fundamental natural bottlenecks and thresholds to their establishment and long-term ecological maintenance. Despite inhabiting similar intertidal positions, the biological traits of these systems differ markedly in structure, phenology, life history, phylogeny and dispersal, suggesting large differences in biophysical interactions. By providing the first systematic comparison between saltmarshes and mangroves, we unravel how the interplay between species-specific life-history traits, biophysical interactions and biogeomorphological feedback processes determine where, when and what wetland can establish, the thresholds to long-term ecosystem stability, and constraints to genetic connectivity between intertidal wetland populations at the landscape level. To understand these process interactions, research into the constraints to wetland development, and biological adaptations to overcome these critical bottlenecks and thresholds requires a truly interdisciplinary approach.

  12. Differences in the Selection Bottleneck between Modes of Sexual Transmission Influence the Genetic Composition of the HIV-1 Founder Virus.

    Directory of Open Access Journals (Sweden)

    Damien C Tully

    2016-05-01

    Full Text Available Due to the stringent population bottleneck that occurs during sexual HIV-1 transmission, systemic infection is typically established by a limited number of founder viruses. Elucidation of the precise forces influencing the selection of founder viruses may reveal key vulnerabilities that could aid in the development of a vaccine or other clinical interventions. Here, we utilize deep sequencing data and apply a genetic distance-based method to investigate whether the mode of sexual transmission shapes the nascent founder viral genome. Analysis of 74 acute and early HIV-1 infected subjects revealed that 83% of men who have sex with men (MSM exhibit a single founder virus, levels similar to those previously observed in heterosexual (HSX transmission. In a metadata analysis of a total of 354 subjects, including HSX, MSM and injecting drug users (IDU, we also observed no significant differences in the frequency of single founder virus infections between HSX and MSM transmissions. However, comparison of HIV-1 envelope sequences revealed that HSX founder viruses exhibited a greater number of codon sites under positive selection, as well as stronger transmission indices possibly reflective of higher fitness variants. Moreover, specific genetic "signatures" within MSM and HSX founder viruses were identified, with single polymorphisms within gp41 enriched among HSX viruses while more complex patterns, including clustered polymorphisms surrounding the CD4 binding site, were enriched in MSM viruses. While our findings do not support an influence of the mode of sexual transmission on the number of founder viruses, they do demonstrate that there are marked differences in the selection bottleneck that can significantly shape their genetic composition. This study illustrates the complex dynamics of the transmission bottleneck and reveals that distinct genetic bottleneck processes exist dependent upon the mode of HIV-1 transmission.

  13. Hurry Up and Wait: Differential Impacts of Congestion, Bottleneck Pressure, and Predictability on Patient Length of Stay

    OpenAIRE

    Berry Jaeker, Jillian Alexandra; Tucker, Anita Lynn

    2012-01-01

    High work load, from high inventory levels, impacts unit processing times, but prior operations management studies have found conflicting results regarding direction. Thus, it is difficult to predict inventory’s effects on productivity a priori, inhibiting effective capacity management in high load systems. We categorize load into in-process inventory (congestion) and incoming inventory, decomposing the latter into its levels of bottleneck (BN) pressure and predictability, and quantify the ma...

  14. Differences in the Selection Bottleneck between Modes of Sexual Transmission Influence the Genetic Composition of the HIV-1 Founder Virus

    Science.gov (United States)

    Tully, Damien C.; Ogilvie, Colin B.; Batorsky, Rebecca E.; Bean, David J.; Power, Karen A.; Ghebremichael, Musie; Bedard, Hunter E.; Gladden, Adrianne D.; Seese, Aaron M.; Amero, Molly A.; Lane, Kimberly; McGrath, Graham; Bazner, Suzane B.; Tinsley, Jake; Lennon, Niall J.; Henn, Matthew R.; Brumme, Zabrina L.; Norris, Philip J.; Rosenberg, Eric S.; Mayer, Kenneth H.; Jessen, Heiko; Kosakovsky Pond, Sergei L.; Walker, Bruce D.; Altfeld, Marcus; Carlson, Jonathan M.; Allen, Todd M.

    2016-01-01

    Due to the stringent population bottleneck that occurs during sexual HIV-1 transmission, systemic infection is typically established by a limited number of founder viruses. Elucidation of the precise forces influencing the selection of founder viruses may reveal key vulnerabilities that could aid in the development of a vaccine or other clinical interventions. Here, we utilize deep sequencing data and apply a genetic distance-based method to investigate whether the mode of sexual transmission shapes the nascent founder viral genome. Analysis of 74 acute and early HIV-1 infected subjects revealed that 83% of men who have sex with men (MSM) exhibit a single founder virus, levels similar to those previously observed in heterosexual (HSX) transmission. In a metadata analysis of a total of 354 subjects, including HSX, MSM and injecting drug users (IDU), we also observed no significant differences in the frequency of single founder virus infections between HSX and MSM transmissions. However, comparison of HIV-1 envelope sequences revealed that HSX founder viruses exhibited a greater number of codon sites under positive selection, as well as stronger transmission indices possibly reflective of higher fitness variants. Moreover, specific genetic “signatures” within MSM and HSX founder viruses were identified, with single polymorphisms within gp41 enriched among HSX viruses while more complex patterns, including clustered polymorphisms surrounding the CD4 binding site, were enriched in MSM viruses. While our findings do not support an influence of the mode of sexual transmission on the number of founder viruses, they do demonstrate that there are marked differences in the selection bottleneck that can significantly shape their genetic composition. This study illustrates the complex dynamics of the transmission bottleneck and reveals that distinct genetic bottleneck processes exist dependent upon the mode of HIV-1 transmission. PMID:27163788

  15. Oracle Database Common Bottleneck Issues Analysis%Oracle数据库常见的瓶颈问题分析

    Institute of Scientific and Technical Information of China (English)

    李文鹏

    2011-01-01

    Oracle database as the world's largest database companies at home and abroad has been applied widely.Article on the current Oracle database common bottleneck issues analyzed and discussed.%Oracle数据库作为全球第一大数据库厂商,在国内外获得了广泛应用。文章对目前Oracle数据库常见的瓶颈问题进行了分析探讨。

  16. Combinatorial Sec pathway analysis for improved heterologous protein secretion in Bacillus subtilis: identification of bottlenecks by systematic gene overexpression

    OpenAIRE

    Chen, Jingqi; Fu, Gang; Gai, Yuanming; Zheng, Ping; Zhang, Dawei; Wen, Jianping

    2015-01-01

    Background Secretory expression of valuable proteins by B. subtilis and its related species has attracted intensive work over the past three decades. Although very high yields can be achieved with homologous proteins, production of heterologous proteins by B. subtilis is unfortunately not the straight forward. The Sec pathway is the major route for protein secretion in B. subtilis. Therefore, the aim of this work was to identify the bottlenecks of the Sec pathway and improve the secretion of ...

  17. Analysis of talent bottleneck of chain retailing business%连锁零售企业人才瓶颈问题浅析

    Institute of Scientific and Technical Information of China (English)

    赵根良

    2012-01-01

    In the chain retailing business operation and management, talent is the foundation of its success and continuous development. With the rapid expansion of chain retailing business, chain retailing business in China has relatively serious talent bottleneck problem. Based on the analysis of the situation and reasons of Chinese chain retailing business talent bottleneck, this article puts forward counter- measures and suggestions to solve Chinese chain retailing business talent bottleneck problem.%在分析了我国连锁零售企业人才瓶颈的现状和原因的基础上,提出了解决这一问题的对策和建议。

  18. Systemic administration of RANKL overcomes the bottleneck of oral vaccine delivery through microfold cells in ileum.

    Science.gov (United States)

    Maharjan, Sushila; Singh, Bijay; Jiang, Tao; Yoon, So-Yeon; Li, Hui-Shan; Kim, Girak; Gu, Min Jeong; Kim, Soo Ji; Park, Ok-Jin; Han, Seung Hyun; Kang, Sang-Kee; Yun, Cheol-Heui; Choi, Yun-Jaie; Cho, Chong-Su

    2016-04-01

    A successful delivery of antigen through oral route requires to overcome several barriers, such as enzymatic barrier of gastrointestinal tract and epithelial barrier that constitutes of microfold cells (M cells) for antigen uptake. Although each barrier represents a critical step in determining the final efficiency of antigen delivery, the transcytosis of antigen by M cells in the follicle-associated epithelium (FAE) to Peyer's patches appears to be a major bottleneck. Considering the systemic administration of receptor activator of nuclear factor (NF)-ĸB ligand (RANKL) induces differentiation of receptor activator of nuclear factor (NF)-ĸB (RANK)-expressing enterocytes into M cells, here, we illustrated a promising approach of antigen delivery using full length transmembrane RANKL (mRANKL). The results showed that the intraperitoneal injection of mRANKL increased the population of dendritic cells and macrophages in mesenteric lymph nodes and spleen. Subsequently, systemic administration of mRANKL resulted in significantly higher number of functional GP2(+) M cells leading higher transcytosis of fluorescent beads through them. To corroborate the effect of mRANKL in antigen delivery through M cells, we orally delivered microparticulate antigen to mice treated with mRANKL. Oral immunization induced strong protective IgA and systemic IgG antibody responses against orally delivered antigen in mRANKL-treated mice. The higher antibody responses are attributed to the higher transcytosis of antigens through M cells. Ultimately, the higher memory B cells and effector memory CD4 T cells after oral immunization in RANKL-treated mice confirmed potency of RANKL-mediated antigen delivery. To the best of our knowledge, this is the first study to demonstrate significant induction of mucosal and humoral immune responses to M cell targeted oral vaccines after the systemic administration of RANKL. PMID:26851393

  19. Raptor mortality in wind farms of southern Spain: mitigation measures on a major migration bottleneck area

    Energy Technology Data Exchange (ETDEWEB)

    Gallego, Antonio-Roman Munoz; Lucas, Manuela De; Casado, Eva; Ferrer, Miguel

    2011-07-01

    Full text: To assess and monitor the impact of wind farms on fauna is crucial if we want to achieve ecologically sustainable development of this renewable energy resource. Today there are clear evidences that the probability of raptor collision depends critically on species behaviour and weather conditions, and the topographic factors related to each windmill. In our study area EIA were not able to predict this differential risk and in these circumstances mitigating the causes of bird mortality becomes a task of major importance, especially to those wind farms located in the Strait of Gibraltar, a water crossing of 14 km at its shortest distance acting as a major migration bottleneck for Paleo-African soaring migrants. We collected all available information on raptor collision from 1992, when the first wind farm was installed, and from 2005 until present a total of 262 turbines, grouped into 20 wind farms, were surveyed in a daily basis through a surveillance program with the main goal of register the actual mortality of birds. A total of 1291 raptors of 19 species were found of which 78.5% correspond to two species, the griffon vulture (Gyps fulvus) and the kestrel (Falco tinnunculus). In order to mitigate the impact on raptors, and particularly on the griffon vulture, in 2007 a program based on selective stopping of turbines was imposed, in collaboration with the environmental competent authority, on new approved projects. During 2008 there was a reduction in mortality by 48%, which remained in 2009 with a remarkably lower economic cost. An analysis of the temporal collision patterns will be presented and discussed, with special attention to those species suffering higher mortality rate, and to those who have some degree of threat. (Author)

  20. Epigeic earthworms exert a bottleneck effect on microbial communities through gut associated processes.

    Directory of Open Access Journals (Sweden)

    María Gómez-Brandón

    Full Text Available BACKGROUND: Earthworms play a critical role in organic matter decomposition because of the interactions they establish with microorganisms. The ingestion, digestion, assimilation of organic material in the gut and then casting is the first step in earthworm-microorganism interactions. The current knowledge of these direct effects is still limited for epigeic earthworm species, mainly those living in man-made environments. Here we tested whether and to what extent the earthworm Eisenia andrei is capable of altering the microbiological properties of fresh organic matter through gut associated processes; and if these direct effects are related to the earthworm diet. METHODOLOGY: To address these questions we determined the microbial community structure (phospholipid fatty acid profiles and microbial activity (fluorescein diacetate hydrolysis in the earthworm casts derived from three types of animal manure (cow, horse and pig manure, which differed in microbial composition. PRINCIPAL FINDINGS: The passage of the organic material through the gut of E. andrei reduced the total microbial biomass irrespective of the type of manure, and resulted in a decrease in bacterial biomass in all the manures; whilst leaving the fungi unaffected in the egested materials. However, unlike the microbial biomass, no such reduction was detected in the total microbial activity of cast samples derived from the pig manure. Moreover, no differences were found between cast samples derived from the different types of manure with regards to microbial community structure, which provides strong evidence for a bottleneck effect of worm digestion on microbial populations of the original material consumed. CONCLUSIONS/SIGNIFICANCE: Our data reveal that earthworm gut is a major shaper of microbial communities, thereby favouring the existence of a reduced but more active microbial population in the egested materials, which is of great importance to understand how biotic interactions

  1. Population aging and migrant workers: bottlenecks in tuberculosis control in rural China.

    Directory of Open Access Journals (Sweden)

    Sumedh Bele

    Full Text Available BACKGROUND: Tuberculosis is a serious global health problem. Its paradigms are shifting through time, especially in rapidly developing countries such as China. Health providers in China are at the forefront of the battle against tuberculosis; however, there are few empirical studies on health providers' perspectives on the challenges they face in tuberculosis control at the county level in China. This study was conducted among health providers to explore their experiences with tuberculosis control in order to identify bottlenecks and emerging challenges in controlling tuberculosis in rural China. METHODS: A qualitative approach was used. Semi-structured, in-depth interviews were conducted with 17 health providers working in various positions within the health system of one rural county (ZJG of China. Data were analyzed based on thematic content analysis using MAXQDA 10 qualitative data analysis software. RESULTS: Health providers reported several problems in tuberculosis control in ZJG county. Migrant workers and the elderly were repeatedly documented as the main obstacles in effective tuberculosis control in the county. At a personal level, doctors showed their frustration with the lack of new drugs for treating tuberculosis patients, and their opinions varied regarding incentives for referring patients. CONCLUSION: The results suggest that several problems still remain for controlling tuberculosis in rural China. Tuberculosis control efforts need to make reaching the most vulnerable populations a priority and encourage local health providers to adopt innovative practices in the local context based on national guidelines to achieve the best results. Considerable changes in China's National Tuberculosis Control Program are needed to tackle these emerging challenges faced by health workers at the county level.

  2. Thermodynamic modelling predicts energetic bottleneck for seabirds wintering in the northwest Atlantic.

    Science.gov (United States)

    Fort, Jérôme; Porter, Warren P; Grémillet, David

    2009-08-01

    Studying the energetics of marine top predators such as seabirds is essential to understand processes underlying adult winter survival and its impact on population dynamics. Winter survival is believed to be the single most important life-history trait in long-lived species but its determinants are largely unknown. Seabirds are inaccessible during this season, so conventional metabolic studies are extremely challenging and new approaches are needed. This paper describes and uses a state-of-the-art mechanistic model, Niche Mapper, to predict energy expenditure and food requirements of the two main seabird species wintering in the northwest Atlantic. We found that energy demand increased throughout the winter phase in both species. Across this period, mean estimated daily energy requirements were 1306 kJ day(-1) for Brünnich's guillemots (Uria lomvia) and 430 kJ day(-1) for little auks (Alle alle) wintering off Greenland and Newfoundland. Mean estimated daily food requirements were 547 g wet food day(-1) for Brünnich's guillemots, and 289 g wet food day(-1) for little auks. For both species and both wintering sites, our model predicts a sharp increase in energy expenditure between November and December, primarily driven by climatic factors such as air temperature and wind speed. These findings strongly suggest the existence of an energetic bottleneck for North Atlantic seabirds towards the end of the year, a challenging energetic phase which might explain recurrent events of winter mass-mortality, so called 'seabird winter wrecks'. Our study therefore emphasizes the relevance of thermodynamics/biophysical modelling for investigating the energy balance of wintering marine top predators and its interplay with survival and population dynamics in the context of global change. PMID:19617442

  3. IDENTIFYING BOTTLENECKS FOR APPROPRIATE INFANT FEEDING IN URBAN SLUMS, ALIGARH CITY.

    Directory of Open Access Journals (Sweden)

    Saira Mehnaz

    2012-04-01

    Full Text Available Introduction: Urban population is increasing rapidly. Majority of these families are poor or landless farmers and labourers, who settle down in peri-urban areas, creating slums. Urban slums are thus growing at an alarming rate. The present study was carried out with the general objective of identifying factors which prevent access to health services. Objectives: 1. To determine the prevalence of stunting, wasting, and underweight in infants and young children. 2. To determine presence of certain micro-environmental and socioeconomic factors associated with poor nutritional status of infants and children. Methodology: Baseline study was carried out in Oct –Nov 2009 (as a part of another ongoing study and data was collected in 110 Mothers who had delivered children during the last one month. In Oct 2010 these families were visited again the infants were followed up. 39 families had shifted to another location or emigrated back to their parent state or village mostly in search of seasonal employment as reported by neighbours. One family refused to cooperate. . Two infants had died. Remaining 68 Mothers were interviewed in friendly informal manner after taking consent for study. Results: (35.4% study subjects had migrated to other areas, as reported by neighbours. Of the 68 mothers interviewed during follow up visit, previous baseline record showed that a majority were 20-30 years of age. , only 2 mothers (2.9% had exclusively breastfed for 6 months. 46 (67.6% said they had not been contacted by any health worker during the last 3 months. All 68 children were malnourished. Immunization status was poor and 94.1% children had suffered from some illness in the last one month. Conclusion: Migration is a problem which makes it difficult for providers to give continuity of care. Capacity building of the community can reduce the the bottlenecks leading to marginalization and exclusion of slum mothers from the mainstream urban health services.

  4. Contact transmission of influenza virus between ferrets imposes a looser bottleneck than respiratory droplet transmission allowing propagation of antiviral resistance.

    Science.gov (United States)

    Frise, Rebecca; Bradley, Konrad; van Doremalen, Neeltje; Galiano, Monica; Elderfield, Ruth A; Stilwell, Peter; Ashcroft, Jonathan W; Fernandez-Alonso, Mirian; Miah, Shahjahan; Lackenby, Angie; Roberts, Kim L; Donnelly, Christl A; Barclay, Wendy S

    2016-01-01

    Influenza viruses cause annual seasonal epidemics and occasional pandemics. It is important to elucidate the stringency of bottlenecks during transmission to shed light on mechanisms that underlie the evolution and propagation of antigenic drift, host range switching or drug resistance. The virus spreads between people by different routes, including through the air in droplets and aerosols, and by direct contact. By housing ferrets under different conditions, it is possible to mimic various routes of transmission. Here, we inoculated donor animals with a mixture of two viruses whose genomes differed by one or two reverse engineered synonymous mutations, and measured the transmission of the mixture to exposed sentinel animals. Transmission through the air imposed a tight bottleneck since most recipient animals became infected by only one virus. In contrast, a direct contact transmission chain propagated a mixture of viruses suggesting the dose transferred by this route was higher. From animals with a mixed infection of viruses that were resistant and sensitive to the antiviral drug oseltamivir, resistance was propagated through contact transmission but not by air. These data imply that transmission events with a looser bottleneck can propagate minority variants and may be an important route for influenza evolution. PMID:27430528

  5. A carrier relaxation bottleneck probed in single InGaAs quantum dots using integrated superconducting single photon detectors

    International Nuclear Information System (INIS)

    Using integrated superconducting single photon detectors, we probe ultra-slow exciton capture and relaxation dynamics in single self-assembled InGaAs quantum dots embedded in a GaAs ridge waveguide. Time-resolved luminescence measurements performed with on- and off-chip detection reveal a continuous decrease in the carrier relaxation time from 1.22 ± 0.07 ns to 0.10 ± 0.07 ns upon increasing the number of non-resonantly injected carriers. By comparing off-chip time-resolved spectroscopy with spectrally integrated on-chip measurements, we identify the observed dynamics in the rise time (τr) as arising from a relaxation bottleneck at low excitation levels. From the comparison with the temporal dynamics of the single exciton transition with the on-chip emission signal, we conclude that the relaxation bottleneck is circumvented by the presence of charge carriers occupying states in the bulk material and the two-dimensional wetting layer continuum. A characteristic τr ∝ P−2∕3 power law dependence is observed suggesting Auger-type scattering between carriers trapped in the quantum dot and the two-dimensional wetting layer continuum which circumvents the phonon relaxation bottleneck.

  6. Childhood leukemia genetic bottleneck phenomenon related to TEL-AML1: the postulation by a mathematical model

    Institute of Scientific and Technical Information of China (English)

    Petar Ivanovski; Ivan Ivanovski; Dimitrije Nikoli(c); Ivana Jovanovi(c)

    2012-01-01

    Childhood leukemia bottleneck phenomenon is the most mysterious corollary of the prenatal origin discovery of leukemogenic chromosome translocations.The bottleneck is evidence that leukemia initiation,by in utero acquired chromosome translocations that generate functional fusion genes,is far more common than the incidence rate of corresponding leukemia.For childhood TEL-AML1+ acute lymphoblastic leukemia (ALL) this equates to approximately 100 times.Practically this means that among a hundred children born with TEL-AML1 fusion gene,only one child will later in its life develop ALL.The key data necessary for unraveling of this mystery were discovered in 2002.It was the level of TEL-AML1 + cells' frequency.The bottleneck is caused by the very low body TEL-AML1 + cell count.Only one out of a thousand B cells carries TEL-AML1 fusion gene.TEL-AML1+ body cell count is low because TEL-AML1 fusion is generated at cell level of 10a to 10-4 just during the late fetal lymphopoiesis i.e.after the 36th gestational week.

  7. Effect of Driver Behavior on Spatiotemporal Congested Traffic Patterns at Highway Bottlenecks in the Framework of Three-Phase Traffic Theory

    OpenAIRE

    Kerner, Boris S.

    2010-01-01

    We present results of numerical simulations of the effect of driver behavior on spatiotemporal congested traffic patterns that result from traffic breakdown at an on-ramp bottleneck. The simulations are made with the Kerner-Klenov stochastic traffic flow model in the framework of three-phase traffic theory. Different diagrams of congested patterns at the bottleneck associated with different driver behavioral characteristics are found and compared each other. An adaptive cruise control (ACC) i...

  8. Low biochemical variability in European fallow deer (Dama dama L.): natural bottlenecks and the effects of domestication.

    Science.gov (United States)

    Randi, E; Apollonio, M

    1988-12-01

    Tissue and blood samples from 180 fallow deer (Dama dama L.) belonging to an Italian free-ranging population were studied for biochemical variability by means of cellulose acetate and polyacrylamide gel electrophoresis. The 51 putative genetic loci successfully resolved showed a very low level of variability (P = 0.020, H = 0.006) in accordance with previously reported data on British and West German populations. That low biochemical polymorphism in European fallow deer populations is discussed taking into account the effects of natural bottlenecks and of domestication. PMID:3230030

  9. Phonon bottleneck in GaAs/Al{sub x}Ga{sub 1−x}As quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Y. C.; Robson, A. J.; Harrison, S.; Zhuang, Q. D.; Hayne, M., E-mail: m.hayne@lancaster.ac.uk [Department of Physics, Lancaster University, Lancaster, LA1 4YB (United Kingdom)

    2015-06-15

    We report low-temperature photoluminescence measurements on highly-uniform GaAs/Al{sub x}Ga{sub 1−x}As quantum dots grown by droplet epitaxy. Recombination between confined electrons and holes bound to carbon acceptors in the dots allow us to determine the energies of the confined states in the system, as confirmed by effective mass calculations. The presence of acceptor-bound holes in the quantum dots gives rise to a striking observation of the phonon-bottleneck effect.

  10. Gas to Power in China. Gas-fired Power in China. Clearing the policy bottleneck

    International Nuclear Information System (INIS)

    -to-be-defined elusive competitive power pooling system. This makes it difficult for gas-fired power plants to fulfil their obligations with the gas suppliers under the long-term take-or-pay gas sales contracts. It also increases the perceived risks of the Chinese market. Last but not least, gas-fired power is such a new phenomenon in the coal-dominated market that power sector professionals have a limited understanding of the gas economics. This led them to treat gas-fired power simply as fossil-fuel based generation source. In addition to the difficulties in sourcing LNG for the proposed LNG projects, lack of a clear supportive policy for gas-fired power at the initial stage of China's gas market development also casts serious doubts about the country's ambitious gas market development plans. To resolve those conflicting issues facing gas-fired power, the Chinese government needs to make a policy pronouncement on gas-fired power in the context of the overall national energy strategies and policies. The key may lie with a differentiated and flexible approach that recognises both the difficulties of the power reform process and the urgency of clearing the policy bottleneck on gas-fired power

  11. Bottlenecks in deriving definitive hematopoietic stem cells from human pluripotent stem cells: a CIRM mini-symposium and workshop report.

    Science.gov (United States)

    Shepard, Kelly A; Talib, Sohel

    2014-07-01

    On August 29, 2013, the California Institute for Regenerative Medicine (CIRM) convened a small group of investigators in San Francisco, CA, to discuss a longstanding challenge in the stem cell field: the inability to derive fully functional, definitive hematopoietic stem cells (HSCs) from pluripotent stem cells (PSCs). To date, PSC-derived HSCs have been deficient in their developmental potential and their ability to self-renew and engraft upon transplantation. Tasked with identifying key challenges to overcoming this "HSC bottleneck", workshop participants identified critical knowledge gaps in two key areas: (a) understanding the ontogeny of human HSCs, and (b) understanding of the intrinsic and extrinsic factors that govern HSC behavior and function. They agreed that development of new methods and tools is critical for addressing these knowledge gaps. These include molecular profiling of key HSC properties, development of new model systems/assays for predicting and assessing HSC function, and novel technological advancements for manipulating cell culture conditions and genetic programs. The workshop produced tangible advances, including providing a current definition of the nature and challenge of the HSC bottleneck and identifying key mechanistic studies of HSC biology that should be prioritized for future funding initiatives (e.g., including higher risk approaches that have potential for high gain). PMID:24973044

  12. Optimization of pigment dyeing process of high performance fibers using feed-forward bottleneck neural networks mapping technique

    Energy Technology Data Exchange (ETDEWEB)

    Fjodorova, Natalja, E-mail: natalja.fjodorova@ki.si [National Institute of Chemistry, Hajdrihova 19, SI-1000, Ljubljana (Slovenia); Novic, Marjana [National Institute of Chemistry, Hajdrihova 19, SI-1000, Ljubljana (Slovenia); Diankova, Tamara [St-Petersburg State University of Technology and Design, Bolshaya Morskaya st. 18, 191186, St. Petersburg (Russian Federation)

    2011-10-31

    Highlights: {yields} Optimum conditions of pigment dying process of high performance fibers were proposed. {yields} The feed-forward bottleneck neural network (FFBN) as a mapping technique was implemented. {yields} We showed the influence of different factors (parameters of pigment dying) on different output responses (quality of pigment dying). - Abstract: Process optimization involves the minimization (or maximization) of an objective function, that can be established from a technical and (or) economic viewpoint taking into account safety of process. The basic idea of the optimization method using neural network (NN) is to replace the model equations (which traditionally obtained using, for example, the surface response design or others methods) by an equivalent NN. The feed-forward bottleneck neural network (FFBN) as a mapping technique is described and evaluated. From the 2D maps the optimal parameters of pigment dyeing of high performance fibers on the bases of poly-amide benzimidazole (PABI) and polyimide (arimid) are discussed. The studied fibers were treated in 32 experiments under the conditions as proposed by the Design of Experiment (DOE), varying five influencing factors. Neural network mapping method enables visualization of process and shows the influence of different factors on different output responses. Optimum parameters were selected upon compromise decision.

  13. Optimization of pigment dyeing process of high performance fibers using feed-forward bottleneck neural networks mapping technique

    International Nuclear Information System (INIS)

    Highlights: → Optimum conditions of pigment dying process of high performance fibers were proposed. → The feed-forward bottleneck neural network (FFBN) as a mapping technique was implemented. → We showed the influence of different factors (parameters of pigment dying) on different output responses (quality of pigment dying). - Abstract: Process optimization involves the minimization (or maximization) of an objective function, that can be established from a technical and (or) economic viewpoint taking into account safety of process. The basic idea of the optimization method using neural network (NN) is to replace the model equations (which traditionally obtained using, for example, the surface response design or others methods) by an equivalent NN. The feed-forward bottleneck neural network (FFBN) as a mapping technique is described and evaluated. From the 2D maps the optimal parameters of pigment dyeing of high performance fibers on the bases of poly-amide benzimidazole (PABI) and polyimide (arimid) are discussed. The studied fibers were treated in 32 experiments under the conditions as proposed by the Design of Experiment (DOE), varying five influencing factors. Neural network mapping method enables visualization of process and shows the influence of different factors on different output responses. Optimum parameters were selected upon compromise decision.

  14. Conservation genetics of the alligator snapping turtle: cytonuclear evidence of range-wide bottleneck effects and unusually pronounced geographic structure

    Science.gov (United States)

    Echelle, A.A.; Hackler, J.C.; Lack, Justin B.; Ballard, S. R.; Roman, J.; Fox, S. F.; Leslie,, David M., Jr.; Van Den Bussche, Ronald A.

    2010-01-01

    A previous mtDNA study indicated that female-mediated gene flow was extremely rare among alligator snapping turtle populations in different drainages of the Gulf of Mexico. In this study, we used variation at seven microsatellite DNA loci to assess the possibility of male-mediated gene flow, we augmented the mtDNA survey with additional sampling of the large Mississippi River System, and we evaluated the hypothesis that the consistently low within-population mtDNA diversity reflects past population bottlenecks. The results show that dispersal between drainages of the Gulf of Mexico is rare (F STmsat  = 0.43, ΦSTmtDNA = 0.98). Past range-wide bottlenecks are indicated by several genetic signals, including low diversity for microsatellites (1.1–3.9 alleles/locus; H e = 0.06–0.53) and mtDNA (h = 0.00 for most drainages; π = 0.000–0.001). Microsatellite data reinforce the conclusion from mtDNA that the Suwannee River population might eventually be recognized as a distinct taxonomic unit. It was the only population showing fixation or near fixation for otherwise rare microsatellite alleles. Six evolutionarily significant units are recommended on the basis of reciprocal mtDNA monophyly and high levels of microsatellite DNA divergence.

  15. Blue Cathodoluminescence from Highly Er-Doped ZnO Thin Films Induced by the Phonon Bottleneck Effect

    Institute of Scientific and Technical Information of China (English)

    张喜田; 刘益春; 马剑刚; 吕有明; 申德振; 许武; 钟国柱; 范希武

    2003-01-01

    The room-temperature blue cathodoluminescence (CL) from highly Er-doped ZnO thin films has been studied by using different electron beam currents (EBCs). The ZnO:Er thin films used in our experiment were prepared by simultaneous evaporation from two sources. The x-ray diffraction spectra show that the thin films have a strong preferential c-axis (0002) orientation with a hexagonal crystalline structure. The blue emission at 455 nm originating from the intra-4 f shell transition (4F5/2.4I15/2) in Er3+ ions was observed at room temperature. The nonlinear dependence of the CL intensity on the EBC shows a more intense blue emission above the threshold EBC of 0. 6 μA, which is attributed to the phonon bottleneck effect.

  16. p -State Luminescence in CdSe Nanoplatelets: Role of Lateral Confinement and a Longitudinal Optical Phonon Bottleneck

    Science.gov (United States)

    Achtstein, Alexander W.; Scott, Riccardo; Kickhöfel, Sebastian; Jagsch, Stefan T.; Christodoulou, Sotirios; Bertrand, Guillaume H. V.; Prudnikau, Anatol V.; Antanovich, Artsiom; Artemyev, Mikhail; Moreels, Iwan; Schliwa, Andrei; Woggon, Ulrike

    2016-03-01

    We evidence excited state emission from p states well below ground state saturation in CdSe nanoplatelets. Size-dependent exciton ground and excited state energies and population dynamics are determined by four independent methods: time-resolved PL, time-integrated PL, rate equation modeling, and Hartree renormalized k .p calculations—all in very good agreement. The ground state-excited state energy spacing strongly increases with the lateral platelet quantization. Depending on its detuning to the LO phonon energy, the PL decay of CdSe platelets is governed by a size tunable LO phonon bottleneck, related to the low exciton-phonon coupling, very large oscillator strength, and energy spacing of both states. This is, for instance, ideal to tune lasing properties. CdSe platelets are perfectly suited to control the exciton-phonon interaction by changing their lateral size while the optical transition energy is determined by their thickness.

  17. Diversity and stability of Aleutian mink disease virus during bottleneck transitions resulting from eradication in domestic mink in Denmark

    DEFF Research Database (Denmark)

    Christensen, Laurids Siig; Hansen, Lene Gram; Chriél, Mariann;

    2011-01-01

    Aleutian mink disease (plasmacytosis) virus (AMDV) in domestic mink (Neovison vison) has been subject to eradication in Denmark since 1976. In 2001, approximately 5% of Danish mink farms were still infected and all were located in the northern part of the peninsula of Jutland. In the present study...... cluster compared with Swedish, Finnish and Dutch isolates and seem to represent a minor fraction of the genetic diversity previously found in Denmark. Stability of nucleoide deviations reveals that the purifying selection of bottlenecks imposed on the AMDV population in Denmark by the stamping out policy...... was a predisposing risk parameter for disease outbreak at a farm, and strain identity substantiates the suggestion that inadequate disinfection is involved in the recurrence of outbreaks. In cases of new introductions to farms it is indicated that contact including transport between farms played a...

  18. Limited population structure, genetic drift and bottlenecks characterise an endangered bird species in a dynamic, fire-prone ecosystem.

    Directory of Open Access Journals (Sweden)

    Sarah M Brown

    Full Text Available Fire is a major disturbance process in many ecosystems world-wide, resulting in spatially and temporally dynamic landscapes. For populations occupying such environments, fire-induced landscape change is likely to influence population processes, and genetic patterns and structure among populations. The Mallee Emu-wren Stipiturus mallee is an endangered passerine whose global distribution is confined to fire-prone, semi-arid mallee shrublands in south-eastern Australia. This species, with poor capacity for dispersal, has undergone a precipitous reduction in distribution and numbers in recent decades. We used genetic analyses of 11 length-variable, nuclear loci to examine population structure and processes within this species, across its global range. Populations of the Mallee Emu-wren exhibited a low to moderate level of genetic diversity, and evidence of bottlenecks and genetic drift. Bayesian clustering methods revealed weak genetic population structure across the species' range. The direct effects of large fires, together with associated changes in the spatial and temporal patterns of suitable habitat, have the potential to cause population bottlenecks, serial local extinctions and subsequent recolonisation, all of which may interact to erode and homogenise genetic diversity in this species. Movement among temporally and spatially shifting habitat, appears to maintain long-term genetic connectivity. A plausible explanation for the observed genetic patterns is that, following extensive fires, recolonisation exceeds in-situ survival as the primary driver of population recovery in this species. These findings suggest that dynamic, fire-dominated landscapes can drive genetic homogenisation of populations of species with low-mobility and specialised habitat that otherwise would be expected to show strongly structured populations. Such effects must be considered when formulating management actions to conserve species in fire-prone systems.

  19. Narrow bottlenecks affect Pea seedborne mosaic virus populations during vertical seed transmission but not during leaf colonization.

    Directory of Open Access Journals (Sweden)

    Frédéric Fabre

    2014-01-01

    Full Text Available The effective size of populations (Ne determines whether selection or genetic drift is the predominant force shaping their genetic structure and evolution. Populations having high Ne adapt faster, as selection acts more intensely, than populations having low Ne, where random effects of genetic drift dominate. Estimating Ne for various steps of plant virus life cycle has been the focus of several studies in the last decade, but no estimates are available for the vertical transmission of plant viruses, although virus seed transmission is economically significant in at least 18% of plant viruses in at least one plant species. Here we study the co-dynamics of two variants of Pea seedborne mosaic virus (PSbMV colonizing leaves of pea plants (Pisum sativum L. during the whole flowering period, and their subsequent transmission to plant progeny through seeds. Whereas classical estimators of Ne could be used for leaf infection at the systemic level, as virus variants were equally competitive, dedicated stochastic models were needed to estimate Ne during vertical transmission. Very little genetic drift was observed during the infection of apical leaves, with Ne values ranging from 59 to 216. In contrast, a very drastic genetic drift was observed during vertical transmission, with an average number of infectious virus particles contributing to the infection of a seedling from an infected mother plant close to one. A simple model of vertical transmission, assuming a cumulative action of virus infectious particles and a virus density threshold required for vertical transmission to occur fitted the experimental data very satisfactorily. This study reveals that vertically-transmitted viruses endure bottlenecks as narrow as those imposed by horizontal transmission. These bottlenecks are likely to slow down virus adaptation and could decrease virus fitness and virulence.

  20. Microscopic theory of traffic-flow instability governing traffic breakdown at highway bottlenecks: Growing wave of increase in speed in synchronized flow.

    Science.gov (United States)

    Kerner, Boris S

    2015-12-01

    We have revealed a growing local speed wave of increase in speed that can randomly occur in synchronized flow (S) at a highway bottleneck. The development of such a traffic flow instability leads to free flow (F) at the bottleneck; therefore, we call this instability an S→F instability. Whereas the S→F instability leads to a local increase in speed (growing acceleration wave), in contrast, the classical traffic flow instability introduced in the 1950s-1960s and incorporated later in a huge number of traffic flow models leads to a growing wave of a local decrease in speed (growing deceleration wave). We have found that the S→F instability can occur only if there is a finite time delay in driver overacceleration. The initial speed disturbance of increase in speed (called "speed peak") that initiates the S→F instability occurs usually at the downstream front of synchronized flow at the bottleneck. There can be many speed peaks with random amplitudes that occur randomly over time. It has been found that the S→F instability exhibits a nucleation nature: Only when a speed peak amplitude is large enough can the S→F instability occur; in contrast, speed peaks of smaller amplitudes cause dissolving speed waves of a local increase in speed (dissolving acceleration waves) in synchronized flow. We have found that the S→F instability governs traffic breakdown-a phase transition from free flow to synchronized flow (F→S transition) at the bottleneck: The nucleation nature of the S→F instability explains the metastability of free flow with respect to an F→S transition at the bottleneck. PMID:26764764

  1. Bottleneck Analysis of the Minimum Cost Problem for the Generalized Network Based on Augmented Forest Structure%基于增广森林结构的一般网络最小费用问题瓶颈分析

    Institute of Scientific and Technical Information of China (English)

    江永亨; 王军; 金以慧

    2003-01-01

    The bottleneck analysis of the minimum cost problem for the generalized network (MCPGN) is dis-cussed. The analysis is based on the network simplex algorithm, which gains negative cost graphs by constructingaugmented forest structure, then augments flows on the negative cost graphs until the optimal revolution is gained.Bottleneck structure is presented after analyzing the augmented forest structure. The negative cost augmentedgraphs are constructed with the bottleneck structure. The arcs that block the negative cost augmented graph arethe elements of the bottleneck. The bottleneck analysis for the generalized circulation problem, the minimum circu-lation problem and the circulation problem are discussed respectively as the basal problems, then that for MCPGNis achieved. An example is presented at the end.

  2. 我国北极通航瓶颈问题分析%Analysis on Arctic shipping bottlenecks for China

    Institute of Scientific and Technical Information of China (English)

    曹玉墀; 刘大刚; 刘军坡

    2012-01-01

      As a result of the global warming,the issues concerning Arctic navigation have drawn increasing attention in the world.However,navigation in the Arctic waters depends on the clear understanding of difficulties and problems.This paper,from the perspective of legislation,marine environment protection,ships and navigation conditions,seafarer training and certification,provides a primary analysis on some bottleneck issues concerning involvement of China in Arctic shipping,for reference by those people engaged in the research of Arctic shipping.%  随着全球气温变暖趋势的显现,北极通航问题日益受到各方面的关注。但是要实施北极通航,必须对可能面临的困难和问题有清楚的认识。文中从法律法规、环境保护、船舶和航行条件,以及船员培训和认证等方面,对中国实施北极通航可能存在的一些瓶颈问题作了初步分析,可为从事北极通航问题研究人员提供参考。

  3. Genetic Evidence of a Population Bottleneck and Inbreeding in the Endangered New Zealand Sea Lion, Phocarctos hookeri.

    Science.gov (United States)

    Osborne, Amy J; Negro, Sandra S; Chilvers, B Louise; Robertson, Bruce C; Kennedy, Martin A; Gemmell, Neil J

    2016-09-01

    The New Zealand sea lion (NZSL) is of high conservation concern due to its limited distribution and its declining population size. Historically, it occupied most of coastal New Zealand, but is now restricted to a few coastal sites in southern mainland New Zealand and the sub-Antarctic Islands. NZSLs have experienced a recent reduction in population size due to sealing in the 1900s, which is expected to have resulted in increased inbreeding and a loss of genetic variation, potentially reducing the evolutionary capacity of the species and negatively impacting on its long-term prospects for survival. We used 17 microsatellite loci, previously shown to have cross-species applications in pinnipeds, to determine locus- and population-specific statistics for 1205 NZSLs from 7 consecutive breeding seasons. We show that the NZSL population has a moderate level of genetic diversity in comparison to other pinnipeds. We provide genetic evidence for a population reduction, likely caused by historical sealing, and a measure of allele sharing/parental relatedness (internal relatedness) that is suggestive of increased inbreeding in pups that died during recent epizootic episodes. We hypothesize that population bottlenecks and nonrandom mating have impacted on the population genetic architecture of NZSLs, affecting its population recovery. PMID:26995741

  4. Breaking the I/O bottleneck for high-compute performance processing with Xtensa LX configurable and extensible processor architecture

    Science.gov (United States)

    Ezer, Gulbin A.

    2005-03-01

    The challenges of new embedded applications have conflicting requirements: complex algorithms, evolving standards, shorter product cycles dictate programmable solutions, and yet, high data bandwidth, compute power and lower power consumption dictate carefully crafted hardwired functional modules. An application specific instruction set processor (ASIP) is ideally suited to provide most of the advantages of hardwired logic, while maintaining the time-to-market and programmability advantages of a general purpose processor. This paper presents the unique blend of high compute performance and i/o bandwidth of the configurable and extensible Xtensa LX ASIP architectures. Xtensa LX provides high compute performance with wide instruction words using multiple operation slots that enable superscalar performance suitable for data-intensive applications. Xtensa LX also provides high I/O bandwidth through its multiple load/store units that provide parallel low latency access or external DMA access to local memories and virtually unlimited number of ports and queues directly connected to the processor core functional units and system control registers, which remove the I/O bottleneck of traditional processors. The advantages of Xtensa LX features are proven with their impressive performance results: 171.6 ConsumerMark on out-of-the-box simulation of EEMBC consumer suite and a BDTIsimMark2000™ score of 6150 at 370MHz.

  5. Juvenile competitive bottleneck in the production of brown trout in hydroelectric reservoirs due to intraspecific habitat segregation

    International Nuclear Information System (INIS)

    Resource utilization and growth of brown trout were studied in four deep (mean depths 16.2 - 37.5 m) Norwegian hydroelectric reservoirs by benthic and pelagic gillnet sampling. In all the reservoirs supplementary stockings are carried out. The brown trout were spatially segregated according to size as the habitat use of small individuals (< 180-220 mm) was completely restricted to benthic habitats, whereas larger individuals mainly utilized the upper strata of pelagic waters. It is argued that the pelagic habitat is the more rewarding, and that small-sized brown trout are forced into the less favourable benthic habitat through social interactions with larger specimens. This is supported by an increase in growth of brown trout from their third to fifth year of life, which seems to be related to the shift from benthic to pelagic behaviour. It is also argued that the conditions for small-sized brown trout may be a bottleneck in the capacity to produce brown trout in hydroelectric reservoirs with limited benthic feeding conditions, despite ample access to food in pelagic habitats. When evaluating the possibility of increasing the yield of brown trout through supplementary stockings, it is therefore important to consider food and growth conditions for all age and size groups of brown trout. In reservoirs with poor benthic feeding conditions it may be necessary to stock with brown trout of sizes that are large enough to utilize pelagic habitat, to avoid the limiting benthic living stage. (Author)

  6. Genetic variability in four Alouatta species measured by means of nine DNA microsatellite markers: genetic structure and recent bottlenecks.

    Science.gov (United States)

    Ruiz-Garcia, M; Escobar-Armel, P; Alvarez, D; Mudry, M; Ascunce, M; Gutierrez-Espeleta, G; Shostell, J M

    2007-01-01

    We used microsatellite DNA to study the population genetics of 4 Alouatta species from Central and South America. Our main findings include the following: (1) A. seniculus had the highest level of microsatellite variability while A. caraya and A. palliata had the lowest mean number of alleles per locus and the lowest expected heterozygosity, respectively; (2) the samples of A. seniculus and A. palliata came from different regions and were not in Hardy-Weinberg equilibrium (HWE) which may indicate a Wahlund effect and differentiated gene pools -- in contrast, A. macconnelli and A. caraya were in HWE; (3) the microsatellite genetic heterogeneity of the 4 Alouatta species was similar to the karyotype divergence found among these Alouatta species; the species pair with the lowest level of heterogeneity (genetic differentiation) was A. seniculus/A. caraya, while the Central American species, A. palliata, was highly differentiated from the other 3 South American species; (4) we recommend the establishment of a conservation plan to help protect A. caraya because the Cornuet and Luikart procedure demonstrated a recent bottleneck for this species. PMID:17303937

  7. The role of host and microbial factors in the pathogenesis of pneumococcal bacteraemia arising from a single bacterial cell bottleneck.

    Directory of Open Access Journals (Sweden)

    Alice Gerlini

    2014-03-01

    Full Text Available The pathogenesis of bacteraemia after challenge with one million pneumococci of three isogenic variants was investigated. Sequential analyses of blood samples indicated that most episodes of bacteraemia were monoclonal events providing compelling evidence for a single bacterial cell bottleneck at the origin of invasive disease. With respect to host determinants, results identified novel properties of splenic macrophages and a role for neutrophils in early clearance of pneumococci. Concerning microbial factors, whole genome sequencing provided genetic evidence for the clonal origin of the bacteraemia and identified SNPs in distinct sub-units of F0/F1 ATPase in the majority of the ex vivo isolates. When compared to parental organisms of the inoculum, ex-vivo pneumococci with mutant alleles of the F0/F1 ATPase had acquired the capacity to grow at low pH at the cost of the capacity to grow at high pH. Although founded by a single cell, the genotypes of pneumococci in septicaemic mice indicate strong selective pressure for fitness, emphasising the within-host complexity of the pathogenesis of invasive disease.

  8. No Genetic Bottleneck in Plasmodium falciparum Wild-Type Pfcrt Alleles Reemerging in Hainan Island, China, following High-Level Chloroquine Resistance▿

    OpenAIRE

    Chen, Nanhua; Gao, Qi; Wang, Shanqing; Wang, Guangze; Gatton, Michelle; Cheng, Qin

    2007-01-01

    Chloroquine-resistant Plasmodium falciparum was highly prevalent in Hainan, China, in the 1970s. Twenty-five years after cessation of chloroquine therapy, the prevalence of P. falciparum wild-type Pfcrt alleles has risen to 36% (95% confidence interval, 22.1 to 52.4%). The diverse origins of wild-type alleles indicate that there was no genetic bottleneck caused by high chloroquine resistance.

  9. Bottlenecks of SME in services and craft enterprises and their elimination in rural areas of the Czech Republic: A trial to use traditional regional economic measures

    OpenAIRE

    Jehle, Raimund

    1998-01-01

    Relatively few studies have explored the bottlenecks of SME of services and craft-enterprises in rural areas of the Czech Republic. On the basis of an theoretical and empirical approach in two sample regions in the Czech Republic these aspects are stressed. Starting form the obser-vation of differences in growth rates of new established enterprises between rural areas and agglomerations by shifts-share analysis a sector with strong locational influences on its development is identified and co...

  10. Human migration through bottlenecks from Southeast Asia into East Asia during Last Glacial Maximum revealed by Y chromosomes.

    Directory of Open Access Journals (Sweden)

    Xiaoyun Cai

    Full Text Available Molecular anthropological studies of the populations in and around East Asia have resulted in the discovery that most of the Y-chromosome lineages of East Asians came from Southeast Asia. However, very few Southeast Asian populations had been investigated, and therefore, little was known about the purported migrations from Southeast Asia into East Asia and their roles in shaping the genetic structure of East Asian populations. Here, we present the Y-chromosome data from 1,652 individuals belonging to 47 Mon-Khmer (MK and Hmong-Mien (HM speaking populations that are distributed primarily across Southeast Asia and extend into East Asia. Haplogroup O3a3b-M7, which appears mainly in MK and HM, indicates a strong tie between the two groups. The short tandem repeat network of O3a3b-M7 displayed a hierarchical expansion structure (annual ring shape, with MK haplotypes being located at the original point, and the HM and the Tibeto-Burman haplotypes distributed further away from core of the network. Moreover, the East Asian dominant haplogroup O3a3c1-M117 shows a network structure similar to that of O3a3b-M7. These patterns indicate an early unidirectional diffusion from Southeast Asia into East Asia, which might have resulted from the genetic drift of East Asian ancestors carrying these two haplogroups through many small bottle-necks formed by the complicated landscape between Southeast Asia and East Asia. The ages of O3a3b-M7 and O3a3c1-M117 were estimated to be approximately 19 thousand years, followed by the emergence of the ancestors of HM lineages out of MK and the unidirectional northward migrations into East Asia.

  11. A range-wide genetic bottleneck overwhelms contemporary landscape factors and local abundance in shaping genetic patterns of an alpine butterfly (Lepidoptera: Pieridae: Colias behrii).

    Science.gov (United States)

    Schoville, Sean D; Lam, Athena W; Roderick, George K

    2012-09-01

    Spatial and environmental heterogeneity are major factors in structuring species distributions in alpine landscapes. These landscapes have also been affected by glacial advances and retreats, causing alpine taxa to undergo range shifts and demographic changes. These nonequilibrium population dynamics have the potential to obscure the effects of environmental factors on the distribution of genetic variation. Here, we investigate how demographic change and environmental factors influence genetic variation in the alpine butterfly Colias behrii. Data from 14 microsatellite loci provide evidence of bottlenecks in all population samples. We test several alternative models of demography using approximate Bayesian computation (ABC), with the results favouring a model in which a recent bottleneck precedes rapid population growth. Applying independent calibrations to microsatellite loci and a nuclear gene, we estimate that this bottleneck affected both northern and southern populations 531-281 years ago, coinciding with a period of global cooling. Using regression approaches, we attempt to separate the effects of population structure, geographical distance and landscape on patterns of population genetic differentiation. Only 40% of the variation in F(ST) is explained by these models, with geographical distance and least-cost distance among meadow patches selected as the best predictors. Various measures of genetic diversity within populations are also decoupled from estimates of local abundance and habitat patch characteristics. Our results demonstrate that demographic change can have a disproportionate influence on genetic diversity in alpine species, contrasting with other studies that suggest landscape features control contemporary demographic processes in high-elevation environments. PMID:22849440

  12. Microscopic Theory of Traffic Flow Instability Governing Traffic Breakdown at Highway Bottlenecks: Growing Wave of Increase in Speed in Synchronized Flow

    CERN Document Server

    Kerner, Boris S

    2015-01-01

    We have revealed a growing local speed wave of increase in speed that can randomly occur in synchronized flow (S) at a highway bottleneck. The development of such a traffic flow instability leads to free flow (F) at the bottleneck; therefore, we call this instability as an S$\\rightarrow$F instability. Whereas the S$\\rightarrow$F instability leads to a local {\\it increase in speed} (growing acceleration wave), in contrast, the classical traffic flow instability introduced in 50s--60s and incorporated later in a huge number of traffic flow models leads to a growing wave of a local {\\it decrease in speed} (growing deceleration wave). We have found that the S$\\rightarrow$F instability can occur only, if there is a finite time delay in driver over-acceleration. The initial speed disturbance of increase in speed (called "speed peak") that initiates the S$\\rightarrow$F instability occurs usually at the downstream front of synchronized flow at the bottleneck. There can be many speed peaks with random amplitudes that ...

  13. Effect of Driver Behavior on Spatiotemporal Congested Traffic Patterns at Highway Bottlenecks in the Framework of Three-Phase Traffic Theory

    CERN Document Server

    Kerner, Boris S

    2010-01-01

    We present results of numerical simulations of the effect of driver behavior on spatiotemporal congested traffic patterns that result from traffic breakdown at an on-ramp bottleneck. The simulations are made with the Kerner-Klenov stochastic traffic flow model in the framework of three-phase traffic theory. Different diagrams of congested patterns at the bottleneck associated with different driver behavioral characteristics are found and compared each other. An adaptive cruise control (ACC) in the framework of three-phase traffic theory introduced by the author (called a "driver alike ACC" (DA-ACC)) is discussed. The effect of DA-ACC-vehicles on traffic flow, in which without the DA-ACC-vehicles traffic congestion occurs at the bottleneck, is numerically studied. We show that DA-ACC-vehicles improve traffic flow considerably without any reduction in driving comfort. It is found that there is a critical percentage of DA-ACC-vehicles in traffic flow: If the percentage of the DA-ACC-vehicle exceeds the critical ...

  14. Critical Metals in Strategic Energy Technologies. Assessing Rare Metals as Supply-Chain Bottlenecks in Low-Carbon Energy Technologies

    International Nuclear Information System (INIS)

    Due to the rapid growth in demand for certain materials, compounded by political risks associated with the geographical concentration of the supply of them, a shortage of these materials could be a potential bottleneck to the deployment of low-carbon energy technologies. In order to assess whether such shortages could jeopardise the objectives of the EU's Strategic Energy Technology Plan (SET-Plan), an improved understanding of these risks is vital. In particular, this report examines the use of metals in the six low-carbon energy technologies of SET-Plan, namely: nuclear, solar, wind, bioenergy, carbon capture and storage (CCS) and electricity grids. The study looks at the average annual demand for each metal for the deployment of the technologies in Europe between 2020 and 2030. The demand of each metal is compared to the respective global production volume in 2010. This ratio (expressed as a percentage) allows comparing the relative stress that the deployment of the six technologies in Europe is expected to create on the global supplies for these different metals. The study identifies 14 metals for which the deployment of the six technologies will require 1% or more (and in some cases, much more) of current world supply per annum between 2020 and 2030. These 14 metals, in order of decreasing demand, are tellurium, indium, tin, hafnium, silver, dysprosium, gallium, neodymium, cadmium, nickel, molybdenum, vanadium, niobium and selenium. The metals are examined further in terms of the risks of meeting the anticipated demand by analysing in detail the likelihood of rapid future global demand growth, limitations to expanding supply in the short to medium term, and the concentration of supply and political risks associated with key suppliers. The report pinpoints 5 of the 14 metals to be at high risk, namely: the rare earth metals neodymium and dysprosium, and the by-products (from the processing of other metals) indium, tellurium and gallium. The report explores a

  15. Achievements and bottlenecks in humanitarian demining EU-funded research: final results from the EC DELVE project

    Science.gov (United States)

    Sahli, Hichem; Bruschini, Claudio; Van Kempen, Luc; Schleijpen, Ric; den Breejen, Eric

    2008-04-01

    The EC DELVE Support Action project has analyzed the bottlenecks in the transfer of Humanitarian Demining (HD) technology from technology development to the use in the field, and drawn some lessons learned, basing itself on the assessment of the European Humanitarian Demining Research and Technology Development (RTD) situation from early 1990 until 2006. The situation at the European level was analyzed with emphasis on activities sponsored by the European Commission (EC). This was also done for four European countries and Japan, with emphasis on national activities. The developments in HD during the last 10 years underline the fact that in a number of cases demining related developments have been terminated or at least put on hold. The study also showed that the funding provided by the EC under the Framework Program for RTD has led directly to the creation of an extensive portfolio of Humanitarian Demining technology development projects. The latter provided a range of research and supporting measures addressing the critical issues identified as a result of the regulatory policies developed in the field of Humanitarian Demining over the last ten years. However, the range of instruments available to the EC to finance the necessary research and development were limited, to pre-competitive research. The EC had no tools or programs to directly fund actual product development. As a first consequence, the EC funding program for development of technology for Humanitarian Demining unfortunately proved to be largely unsuitable for the small-scale development needed in a field where there is only a very limited market. As a second consequence, most of the research has been demonstrator-oriented. Moreover, the timeframe for RTD in Humanitarian Demining has not been sufficiently synchronized with the timeframe of the EC policies and regulations. The separation of the Mine Action and RTD funding streams in the EC did also negatively affect the take-up of new technologies. As a

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

    Institute of Scientific and Technical Information of China (English)

    吴德华; 邱志军

    2015-01-01

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

  17. 学前教育事业发展的瓶颈问题讨论%Bottlenecks in the Development of Preschool Education

    Institute of Scientific and Technical Information of China (English)

    段媛媛

    2015-01-01

    To achieve the goal of the current development of preschool education, preschool education reform and develop-ment so that more effective and targeted preschool education should be aware of the bottlenecks in the development of China, recognize problems of practical reasons. Bottlenecks preschool education should focus on the development of China include:the rational allocation of educational resources, investment funds issue preschool finance, office park construction quality as-sessment and management mechanisms and survival kindergarten teachers and professional development.%为实现当前学前教育发展的目标,使学前教育改革和发展更具有效性和针对性,应了解我国学前教育事业发展中的瓶颈,认清问题产生的现实原因.我国学前教育事业发展应关注的瓶颈问题包括:教育资源的合理配置问题,学前教育财政经费的投入问题,办园质量评估与管理机制建设以及幼儿园教师生存与专业发展问题.

  18. Demographic and genetic factors in the recovery or demise of ex situ populations following a severe bottleneck in fifteen species of Hawaiian tree snails.

    Science.gov (United States)

    Price, Melissa R; Sischo, David; Pascua, Mark-Anthony; Hadfield, Michael G

    2015-01-01

    Wild populations of endangered Hawaiian tree snails have declined precipitously over the last century due to introduced predators and other human impacts. Life history traits, such as very low fecundity (species were collected from the wild to initiate captive-reared populations as a hedge against extinction. This small number of founders resulted in a severe bottleneck in each of the captive-reared populations. We identified key demographic parameters that predicted population recovery from this bottleneck. Species with captive populations that produced between two and four offspring per adult per year and had 20-50% of those offspring survive to maturity recovered to numbers above 100 individuals, and maintained viable populations following a decline that occurred between 2009 and 2014. Those populations that had less than two offspring per adult per year and less than 20% survival to maturity did not reach 100 individuals in captivity, and many of these populations died out during the recent decline. We suggest that small reductions in fitness may contribute to extirpation in taxa with inherently low fecundity, by keeping populations below a threshold number essential to long-term recovery. Future ex situ populations should be founded with no less than 15 adults, and maintained in conditions closely approximating the temperature and humidity of source locations to optimize fitness. Permanent translocations of wild populations for conservation purposes will be more likely to succeed with greater than 100 adults, and should be limited to locations with a similar climate to source locations. PMID:26587358

  19. Maintenance of genetic diversity in an introduced island population of guanacos after seven decades and two severe demographic bottlenecks: implications for camelid conservation.

    Science.gov (United States)

    González, Benito A; Orozco-Terwengel, Pablo; von Borries, Rainer; Johnson, Warren E; Franklin, William L; Marín, Juan C

    2014-01-01

    Fifteen guanacos were introduced to Staats Island in the Falklands/Malvinas archipelago from Patagonia in the 1930s. Twenty five years later, the population was culled from 300 to 10-20 individuals, but quickly rebounded to a population of almost 400 animals that today retain the genetic signature of the founding event and later bottleneck. The goals of this study were to (i) make a genetic assessment of this island population through comparisons with mainland populations and simulations, and (ii) assess the likely source-population of the introduced guanacos. Genetic variation was estimated from 513 bp of mitochondrial DNA sequence and 15 microsatellite loci among 154 guanacos collected from eight localities, including the adjacent mainland and the islands of Tierra del Fuego and Staats Island. Of the 23 haplotypes observed among our samples, the Staats Island population only contained three haplotypes, all of which were shared with the coastal Monte Leon population in southern Patagonia. Mitochondrial DNA and microsatellite variations on Staats Island were comparable to most mainland populations and greater than those observed on Tierra del Fuego. Patterns of genetic structure suggest that the Staats Island guanaco population was founded with animals from southern Patagonia (as opposed to northern Patagonia or Tierra del Fuego), but that effective reductions in population size lasted only a few generations and that surviving animals were a random sample of the pre-bottleneck genetic variation. PMID:24663026

  20. Widening Synthesis Bottlenecks: Realization of Ultrafast and Continuous-Flow Synthesis of High-Silica Zeolite SSZ-13 for NOx Removal.

    Science.gov (United States)

    Liu, Zhendong; Wakihara, Toru; Oshima, Kazunori; Nishioka, Daisuke; Hotta, Yuusuke; Elangovan, Shanmugam P; Yanaba, Yutaka; Yoshikawa, Takeshi; Chaikittisilp, Watcharop; Matsuo, Takeshi; Takewaki, Takahiko; Okubo, Tatsuya

    2015-05-01

    Characteristics of zeolite formation, such as being kinetically slow and thermodynamically metastable, are the main bottlenecks that obstruct a fast zeolite synthesis. We present an ultrafast route, the first of its kind, to synthesize high-silica zeolite SSZ-13 in 10 min, instead of the several days usually required. Fast heating in a tubular reactor helps avoid thermal lag, and the synergistic effect of addition of a SSZ-13 seed, choice of the proper aluminum source, and employment of high temperature prompted the crystallization. Thanks to the ultra-short period of synthesis, we established a continuous-flow preparation of SSZ-13. The fast-synthesized SSZ-13, after copper-ion exchange, exhibits outstanding performance in the ammonia selective catalytic reduction (NH3 -SCR) of nitrogen oxides (NOx ), showing it to be a superior catalyst for NOx removal. Our results indicate that the formation of high-silica zeolites can be extremely fast if bottlenecks are effectively widened. PMID:25801140

  1. Physician deficit in USA - where is the bottleneck? [Ärztemangel in den USA - wo wird es eng?

    Directory of Open Access Journals (Sweden)

    Walid, M. Sami

    2009-05-01

    Full Text Available [english] The population of physician professionals in the US has been carefully controlled over the last century to ensure profitable work for people in the profession and provide physician workforce for the nation. However, the emergence of managed care in the US has spurred speculations that the US will experience a substantial excess of physicians by the beginning of the 21st century. In light of these forecasts, the number of residency positions funded by Medicare has been restricted. Additionally, enrollment at allopathic medical schools has been decreasing over the last two decades of the Twentieth Century. It is now evident that those predictions were erroneous and that the current supply of physicians does not exceed the demand for their services. That is why the Association of American Medical Colleges now aims to increase the number of US medical school graduates by 3,000 yearly by the year 2015. However, even if this difficult mission can be accomplished, the US can still have a deficit of 200,000 physicians by the year 2020. The reason is the bottleneck that controls the flow of medical graduates aiming to enter residency programs and get clinical training in order to obtain the license required to practice medicine. With the restriction on the number of Medicare-funded residency positions in the US an increase in US medical school graduates will only displace an equal number of international medical graduates applying for residency positions and consequently reduce the number of international medical graduates who join the physician workforce. This will probably not increase the number of practicing physicians. Shortage of physicians will remain an issue and undeniably make access to medical care problematic for all citizens. [german] Im 20. Jahrhundert wurde die Zahl der Ärzte in den Vereinigten Staaten sorgfältig reguliert, um lohnende Arbeitsbedingungen im ärztlichen Beruf und die Versorgung mit Ärzten für die Bev

  2. Using 5S Field Management Activities to Promote the TOC Bottleneck Management in Workshop%运用5S现场管理活动推进车间实施TOC瓶颈管理

    Institute of Scientific and Technical Information of China (English)

    史丙强

    2014-01-01

    The 5S on-site management is the tool of production system to carry out TOC bottleneck management, and makes the TOC bottleneck management easy to work. Bottleneck management thought provides guidance and direction for the development of 5S on-site management work.%院5S现场管理是生产系统推行TOC瓶颈管理的工具,使TOC瓶颈管理工作开展简单易行;瓶颈管理的思想,为5S现场管理工作的开展提供指导,指明方向。

  3. Development status, bottleneck and trend of China cosmetic industry%我国化妆品行业发展现状、瓶颈及趋势

    Institute of Scientific and Technical Information of China (English)

    郭华山

    2012-01-01

    China cosmetic market status and features were introduced, and its import and export data were analyzed. Meanwhile, both current problems and bottleneck in the process of cosmetic market development as well as future measures and strategies were pointed out. Finally, development trend of cosmetic industry was put forward.%对中国整个化妆品市场现状和特征进行了阐述,对2011年的进出口数据进行了深入分析。同时,指出了中国化妆品市场发展过程中遇到的问题、发展瓶颈以及今后几年的发展措施和战略。最后,对今后化妆品行业的发展趋势进行了总结。

  4. A comparison of the psychological refractory period and prioritized processing paradigms: Can the response-selection bottleneck model explain them both?

    Science.gov (United States)

    Miller, Jeff; Durst, Moritz

    2015-10-01

    Four experiments examined whether well-established phenomena from the psychological refractory period (PRP) paradigm are also observed in the prioritized processing paradigm, as would be expected from a common description of the 2 paradigms with the response selection bottleneck (RSB) model. Consistent with a generalization of the RSB model to the prioritized processing paradigm, Experiments 1 and 2 showed that this paradigm yields effects of SOA and stimulus discriminability analogous to those observed in the PRP paradigm. In Experiments 3 and 4, however, overall RTs and effect sizes differed between the PRP and prioritized processing paradigms in ways that are difficult to explain within the RSB model. Understanding the differences between these 2 paradigms offers considerable promise as a way to extend the RSB model beyond the domain of the PRP paradigm and to generalize our understanding of multitasking interference. PMID:26168143

  5. Enriching the Metadata on CERN Document Server And Implementation of a Book Acquisition System To Predict the potential bottlenecks in availability of records in Library

    CERN Document Server

    Ahuja, Chakshu

    2015-01-01

    The automated script for data acquisition project ( bibtasklet ) which aims to enhance existing metadata in our CERN Document Server with data from Springer was implemented. An implicit part of this task is to manage disambiguation (within incoming data), removal of multiple entries, handle replications between new and existing records and further automate the latest file upload task to CDS. All such elements and their corresponding changes are integrated within Invenio to make the upgraded metadata available on the CDS. Another implementation was to make a web interface for the invenio software to calculate the normalized loan period to help the librarians to predict bottleneck on the books on loan over certain period of time and facilitate their decision to buy the new records accordingly.

  6. 我国微型企业融资瓶颈分析%Analysis of Financing Bottlenecks in the Course of China's Micro-enterprise's Development

    Institute of Scientific and Technical Information of China (English)

    谭淑霞

    2012-01-01

    近年来,在地区经济的发展中,微型企业发挥着越来越为重要的作用,已经成为吸纳地区就业的重要力量.本文针对微型企业发展中融资瓶颈问题进行了深入分析,并提出提高我国微型企业融资效率的对策.%In recent years, Micro-enterprises play an increasingly important role in the regional economic development. It has become an important force for employment. This paper makes an in-depth analysis of the financing bottlenecks in the course of the micro-enterprise's development. And then some strategies has been proposed to increase the efficiency of the micro-enterprise financing.

  7. Pathways of Lipid Metabolism in Marine Algae, Co-Expression Network, Bottlenecks and Candidate Genes for Enhanced Production of EPA and DHA in Species of Chromista

    Directory of Open Access Journals (Sweden)

    Alice Mühlroth

    2013-11-01

    Full Text Available The importance of n-3 long chain polyunsaturated fatty acids (LC-PUFAs for human health has received more focus the last decades, and the global consumption of n-3 LC-PUFA has increased. Seafood, the natural n-3 LC-PUFA source, is harvested beyond a sustainable capacity, and it is therefore imperative to develop alternative n-3 LC-PUFA sources for both eicosapentaenoic acid (EPA, 20:5n-3 and docosahexaenoic acid (DHA, 22:6n-3. Genera of algae such as Nannochloropsis, Schizochytrium, Isochrysis and Phaedactylum within the kingdom Chromista have received attention due to their ability to produce n-3 LC-PUFAs. Knowledge of LC-PUFA synthesis and its regulation in algae at the molecular level is fragmentary and represents a bottleneck for attempts to enhance the n-3 LC-PUFA levels for industrial production. In the present review, Phaeodactylum tricornutum has been used to exemplify the synthesis and compartmentalization of n-3 LC-PUFAs. Based on recent transcriptome data a co-expression network of 106 genes involved in lipid metabolism has been created. Together with recent molecular biological and metabolic studies, a model pathway for n-3 LC-PUFA synthesis in P. tricornutum has been proposed, and is compared to industrialized species of Chromista. Limitations of the n-3 LC-PUFA synthesis by enzymes such as thioesterases, elongases, acyl-CoA synthetases and acyltransferases are discussed and metabolic bottlenecks are hypothesized such as the supply of the acetyl-CoA and NADPH. A future industrialization will depend on optimization of chemical compositions and increased biomass production, which can be achieved by exploitation of the physiological potential, by selective breeding and by genetic engineering.

  8. Ancient and contemporary DNA reveal a pre-human decline but no population bottleneck associated with recent human persecution in the kea (Nestor notabilis).

    Science.gov (United States)

    Dussex, Nicolas; Rawlence, Nicolas J; Robertson, Bruce C

    2015-01-01

    The impact of population bottlenecks is an important factor to consider when assessing species survival. Population declines can considerably limit the evolutionary potential of species and make them more susceptible to stochastic events. New Zealand has a well documented history of decline of endemic avifauna related to human colonization. Here, we investigate the genetic effects of a recent population decline in the endangered kea (Nestor notabilis). Kea have undergone a long-lasting persecution between the late 1800s to 1970s where an estimated 150,000 kea were culled under a governmental bounty scheme. Kea now number 1,000-5,000 individuals in the wild and it is likely that the recent population decline may have reduced the genetic diversity of the species. Comparison of contemporary (n = 410), historical (n = 15) and fossil samples (n = 4) showed a loss of mitochondrial diversity since the end of the last glaciation (Otiran Glacial) but no loss of overall genetic diversity associated with the cull. Microsatellite data indicated a recent bottleneck for only one population and a range-wide decline in Ne dating back some 300 - 6,000 years ago, a period predating European arrival in NZ. These results suggest that despite a recent human persecution, kea might have experienced a large population decline before stabilizing in numbers prior to human settlement of New Zealand in response to Holocene changes in habitat distribution. Our study therefore highlights the need to understand the respective effects of climate change and human activities on endangered species dynamics when proposing conservation guidelines. PMID:25719752

  9. Ancient and contemporary DNA reveal a pre-human decline but no population bottleneck associated with recent human persecution in the kea (Nestor notabilis.

    Directory of Open Access Journals (Sweden)

    Nicolas Dussex

    Full Text Available The impact of population bottlenecks is an important factor to consider when assessing species survival. Population declines can considerably limit the evolutionary potential of species and make them more susceptible to stochastic events. New Zealand has a well documented history of decline of endemic avifauna related to human colonization. Here, we investigate the genetic effects of a recent population decline in the endangered kea (Nestor notabilis. Kea have undergone a long-lasting persecution between the late 1800s to 1970s where an estimated 150,000 kea were culled under a governmental bounty scheme. Kea now number 1,000-5,000 individuals in the wild and it is likely that the recent population decline may have reduced the genetic diversity of the species. Comparison of contemporary (n = 410, historical (n = 15 and fossil samples (n = 4 showed a loss of mitochondrial diversity since the end of the last glaciation (Otiran Glacial but no loss of overall genetic diversity associated with the cull. Microsatellite data indicated a recent bottleneck for only one population and a range-wide decline in Ne dating back some 300 - 6,000 years ago, a period predating European arrival in NZ. These results suggest that despite a recent human persecution, kea might have experienced a large population decline before stabilizing in numbers prior to human settlement of New Zealand in response to Holocene changes in habitat distribution. Our study therefore highlights the need to understand the respective effects of climate change and human activities on endangered species dynamics when proposing conservation guidelines.

  10. Correction: Forrester, N.L.; Coffey, L.L.; Weaver, S.C. Arboviral Bottlenecks and Challenges to Maintaining Diversity and Fitness during Mosquito Transmission. Viruses 2014, 6, 3991–4004

    Directory of Open Access Journals (Sweden)

    Naomi L. Forrester

    2014-11-01

    Full Text Available In the original manuscript, Forrester, N.L.; Coffey, L.L.; Weaver, S.C. Arboviral Bottlenecks and Challenges to Maintaining Diversity and Fitness during Mosquito Transmission. Viruses 2014, 6, 3991–4004, Figure 1 contains an error, the third bottle was absent from the figure:[...

  11. Empirical Study for Improving the Traffic Conditions at Bottleneck Road Sections%瓶颈路段交通改善实证研究

    Institute of Scientific and Technical Information of China (English)

    李妙君; 孙全欣; 杨静

    2011-01-01

    城市道路路网中,瓶颈路段的存在对路网通行能力有显著的影响.本文归纳了瓶颈路段存在的两类常见问题:由于拆迁、开发遗留等造成的瓶颈路拥堵;以及铁路、桥等阻碍造成的瓶颈路拥堵.对断头路、瓶颈路的改善措施进行了梳理.结合姚家园路区域-朝阳公园桥案例展开了实证研究,研究表明,断头路的存在对路网的通达性有明显影响;合理调节支路的分流量,可以减轻路网节点的拥堵程度;打通断头路,路网的非直线系数提高,更加方便路网中节点的交流;畸形交叉口的改善,使路网的连接度提高17.5%.%The road sections as bottlenecks of a road network decrease the traffic capacity of the road network significantly.The reasons for making bottleneck road sections are summarized in this study.They include the bad planning of the urban roads in the process of urban development and the influence from the railway lines and bridges in the urban areas.Based on the study of the Chaoyang Park Bridge around Yaojiayuan Road, it is proved that break road sections have a significant impact on the capacity of the road network and sharing part of the traffic volume on arterial roads to branch roads can release the congestion level at the nodes the road network.Smoothing break road sections can increase the value of the non-linear coefficient of the road network and make the connections between the nodes of the road network more easily.Moreover, improving the traffic conditions at intersections whose configurations are irregular can increase the accessibility of the road network by 17.5%.

  12. The Mouse-colored Tyrannulet (Phaeomyias murina) is a species complex that includes the Cocos Flycatcher (Nesotriccus ridgwayi), an island form that underwent a population bottleneck.

    Science.gov (United States)

    Zucker, Marc R; Harvey, Michael G; Oswald, Jessica A; Cuervo, Andrés; Derryberry, Elizabeth; Brumfield, Robb T

    2016-08-01

    Simultaneous examination of evolutionary history in island forms and closely related mainland relatives can provide reciprocal insight into the evolution of island and mainland faunas. The Cocos Flycatcher (Nesotriccus ridgwayi) is a small tyrant flycatcher (Tyrannidae) endemic to Cocos Island, an oceanic island in the eastern Pacific Ocean. We first established its close relationship to the mainland species Mouse-colored Tyrannulet (Phaeomyias murina) using a phylogeny from genome-wide ultraconserved elements and exons. We then used mitochondrial DNA to explore the relationships between Nesotriccus and Phaeomyias populations from across its distribution in Central and South America. We found that Nesotriccus is nested within the Phaeomyias evolutionary tree, and that Phaeomyias represents a complex of at least four evolutionarily distinct species that differ in plumage, voice, and habitat association. Nesotriccus underwent a population bottleneck subsequent to its divergence from Central American and northern South American Phaeomyias populations in the middle Pleistocene. The 46 UCE loci containing alleles that are fixed between the two species are widely distributed across the genome, which suggests that selective or neutral processes responsible for divergence have occurred genome-wide. Overall, our simultaneous examination of Phaeomyias and Nesotriccus revealed divergent levels of genetic diversity and evolutionary histories between island and mainland forms. PMID:27126184

  13. Genetic Variability of Bovine Viral Diarrhea Virus and Evidence for a Possible Genetic Bottleneck during Vertical Transmission in Persistently Infected Cattle.

    Directory of Open Access Journals (Sweden)

    Natalie Dow

    Full Text Available Bovine viral diarrhea virus (BVDV, a Pestivirus in the family Flaviviridae, is an economically important pathogen of cattle worldwide. The primary propagators of the virus are immunotolerant persistently infected (PI cattle, which shed large quantities of virus throughout life. Despite the absence of an acquired immunity against BVDV in these PI cattle there are strong indications of viral variability that are of clinical and epidemiological importance. In this study the variability of E2 and NS5B sequences in multiple body compartments of PI cattle were characterized using clonal sequencing. Phylogenetic analyses revealed that BVDV exists as a quasispecies within PI cattle. Viral variants were clustered by tissue compartment significantly more often than expected by chance alone with the central nervous system appearing to be a particularly important viral reservoir. We also found strong indications for a genetic bottleneck during vertical transmission from PI animals to their offspring. These quasispecies analyses within PI cattle exemplify the role of the PI host in viral propagation and highlight the complex dynamics of BVDV pathogenesis, transmission and evolution.

  14. 物联网产业发展现状及瓶颈研究%Status Quo and Development Bottleneck of Internet of Things

    Institute of Scientific and Technical Information of China (English)

    刘勇燕; 郭丽峰

    2012-01-01

    物联网产业是当前重大战略性新型产业之一,是后金融危机时代推进产业结构升级、提升信息产业发展的基础和形势.在对物联网产业的内涵、体系结构进行系统阐述和分析基础上,基于当前物联网产业发展的基础和形势,重点分析了物联网产业发展过程中在标准规范、核心技术、稀缺资源、信息安全、知识产权保护等方面亟待研究和解决的瓶颈问题.%Internet of things is one of significant strategic emerging industries, is the engine for industry structure promotion in postfinancial-crisis era. This article illustrates the concept and architecture of Internet of things, and analyzes bottleneck problems on standards, core technology, scarce resources, information security and intellectual property protection in the development of this industry.

  15. 发展大学生领导力教育的瓶颈及对策%The Bottlenecks and Countermeasures on the Leadership Education of College Students

    Institute of Scientific and Technical Information of China (English)

    张恒龙; 张书磊

    2012-01-01

    世界各国的经验表明,高校开展大学生领导力教育有利于大学生更好地适应未来不断变化发展的现代社会。近些年,我国也开始关注大学生领导力教育问题,但在发展大学生领导力教育过程中存在定位有失偏颇、理解不够全面、教育资源的开发与利用不足等三大瓶颈。为此,对大学生领导力教育进行恰当定位,从大学生成长成才的角度出发开展领导力教育。探索大学生领导力教育长效机制显得十分紧迫和必要。%The experience of leadership education for college students around the world shows that it's helpful for them to better adapt to the changing modem society. Recently more and more universities have launched some projects of leadership education for college students in China, but in the process there are three bottlenecks. One is that many people haven't realized the importance of leadership education for college students; the second is that people haven't fully understood the conception; the third is that the form of leadership education is not rich. Therefore, we should correct the position of leadership education for coil perspective of comprehensive development, and explore the education. lasting ege students, develop leadership from the effect mechanism of student leadership education.

  16. The Bottleneck and Breakthrough in Telecom Fraud Investigation%电信诈骗犯罪侦查的瓶颈及其突破

    Institute of Scientific and Technical Information of China (English)

    杨郁娟

    2015-01-01

    The bottleneck of telecom fraud investiga tion mainly existed in the scene, case-combining and collaboration investigation. The scene investigation for the telecom fraud and its content are different with the others, in which we must focus on discovering, fixing and extracting the electronic data and interrogate suspects in time. In case-combing investigation, there are problems of the negative attitude and the insufficient accordance. In which we must regulate it through the information construction. In the collaborative investigation, many departments and external organs might be involved besides the public security normal collaboration, namely as collaboration with banks and international cooperation.%电信诈骗犯罪侦查瓶颈主要存在于现场勘查、并案侦查、侦查协作等环节。电信诈骗犯罪现场勘查的地位及其内容等与其他犯罪现场勘查有所不同,应注重电子数据的发现、固定和提取,将现场勘查与即时讯问犯罪嫌疑人密切结合;电信诈骗犯罪并案侦查存在并案不积极和并案依据较少的问题,应通过信息化建设将电信诈骗犯罪并案侦查纳入规范化轨道;在侦查协作方面,除了公安机关内部的常规协作外,更多的是要加强侦查部门与外部机构的协作,即公安机关与银行的协作以及国际警务合作。

  17. Progress and Yield Bottleneck of Aerobic Rice in the North China Plain: A Case Study of Varieties Handao 297 and Handao 502

    Institute of Scientific and Technical Information of China (English)

    XIE Guang-hui; YU Jun; WANG Hua-qi; BAM Bouman

    2008-01-01

    Aerobic rice has been considered a promising rice cultivation system as water scarcity is increasing in the world. This article summarizes the advances in aerobic rice management researches in the North China Plain, focusing on yield formation and its bottleneck. High-yielding and good-quality aerobic rice varieties adapted to aerobic soil conditions have been released officially and adopted by farmers in North China. The varieties Handao 502 and Handao 297 have been recognized as the most promising varieties reaching a yield level ranging 3.5-5.0t ha-1 with 450-650mm water input. Compared with lowland rice, water input in aerobic rice was more than 50% lower, and water productivity was 60% higher. Researches on responses of rice cultivars to nitrate nitrogen (N) and ammonium N supplied at early growth stages provided the first evidence for a preference of aerobic rice HD 297 for nitrate N supply, compared with the lowland rice variety. Zinc uptake studies demonstrated that introduction of aerobic rice system on calcareous soils may increase zinc deficiency problems. Sink size was identified as the limitation of aerobic rice yield, because its spikelet number m-2 was too low (20000-24000) compared with the lowland rice. For future research, more attention is suggested to be paid to yield formation focusing on effects of water regimes on tiller dynamics. Understanding of nutrient uptake and response to fertilization effects are also urgently required to establish optimized crop management technology. Additionally, alternative cropping systems based on aerobic rice should be established, and key sustainability and environmental impact issues in the systems need to be identified.

  18. 突破初中英语写作瓶颈的策略分析%Strategies to Break the Bottleneck of Junior High School English Writing

    Institute of Scientific and Technical Information of China (English)

    邓剑昆

    2014-01-01

    英语学习包括了听、说、读、写四个部分,在初中英语教学中,写作教学是不可缺少的重要组成部分。英语作文将词汇、结构、语法等集于一体,写作教学能够促进学生综合语言运用能力。但是,初中英语写作教学现状不容乐观,英语写作不仅是学生学习的薄弱环节,同时也是英语教师在教学中的瓶颈之一。因此,本文就针对初中英语写作教学中存在的问题进行探讨分析,提出了一些写作教学措施,从而提高教学质量,促进初中生英语写作水平。%English learning includes listening, speaking, reading and writing four parts, in junior high school English teach-ing, teaching writing is an important and indispensable component. The vocabulary of English composition, structure, gram-mar, etc. in one set, writing instruction can promote students' comprehensive ability to use language. However, the current situation is not optimistic teaching junior high school English writing;students learn English writing is not only weak link, but also one of the bottlenecks in the teaching of English teachers. Therefore, this article is for junior high school English Writing discuss the problems in the analysis, put forward some writing teaching measures to improve the quality of teaching and promoting junior high school English writing skills.

  19. Phylogeography of postglacial range expansion in Juglans mandshurica (Juglandaceae) reveals no evidence of bottleneck, loss of genetic diversity, or isolation by distance in the leading-edge populations.

    Science.gov (United States)

    Wang, Wen-Ting; Xu, Bing; Zhang, Da-Yong; Bai, Wei-Ning

    2016-09-01

    The past studies of postglacial recolonization patterns in high latitude regions have revealed a significant role of dispersal capacity in shaping the genetic diversity and population structure of temperate trees. However, most of these studies have focused on species with long-distance dispersal followed by exponential population growth and were therefore unable to reveal the patterns in the case of a gradual expansion. Here we studied the impacts of postglacial range expansions on the distribution of genetic diversity in the Manchurian walnut (Juglans mandshurica), a common tree of East Asian cool-temperate deciduous forests that apparently lacks long-distance seed dispersal ability. The genetic diversity and structure of 19 natural walnut populations in Northeast China and the Korean Peninsula were examined using 17 nuclear simple sequence repeat (SSR) loci. Potential habitats under current and past climatic conditions were predicted using the ecological niche modelling (ENM) method. Bayesian clustering analysis revealed three groups, which were inferred to have diverged through multiple glacial-interglacial cycles in multiple refugia during the Quaternary Period. ENM estimated a southward range shift at the LGM, but high suitability scores still occurred in the western parts of the Changbai Mountains (Northeast China), the Korean peninsula and the exposed seafloor of the Yellow Sea. In contrast to most other cool-temperate trees co-occurring in the same region, the Manchurian walnut did not show any evidence of a population bottleneck, loss of genetic diversity or isolation by distance during the postglacial expansion. Our study clearly indicates that current northern populations originated from one glacial lineage and recolonization via a gradually advancing front due to the lack of a long-distance seed dispersal mechanism led to no latitudinal decrease in genetic diversity. PMID:27346642

  20. Mitigating SDN controller performance bottlenecks

    DEFF Research Database (Denmark)

    Caba, Cosmin Marius; Soler, José

    2015-01-01

    The centralization of the control plane decision logic in Software Defined Networking (SDN) has raised concerns regarding the performance of the SDN Controller (SDNC) when the network scales up. A number of solutions have been proposed in the literature to address these concerns. This paper propo...

  1. Pompen zijn vaak de bottleneck

    NARCIS (Netherlands)

    Wit-Blok, M. de

    2014-01-01

    Leon Geers, senior research scientist bij TNO Process & Instrumentation Development: “Met het verbeteren van de beheersbaarheid en efficiëntie van de processen zijn er nieuwe ‘zwakste schakels’ ontstaan. Eén daarvan vormen pompen.

  2. Study on Identification and Optimization of Bottlenecks in Production Logistics Processes Based on Queue Network Theory%基于排队网络理论的生产物流瓶颈识别与优化研究

    Institute of Scientific and Technical Information of China (English)

    张仕军

    2014-01-01

    针对制造系统多品种小批量生产模式下物流瓶颈转移的复杂问题,在对排队网络理论进行深入研究的基础上,建立了不同工站利用率和生产负荷的关系,并针对两类工件和四个工站的排队网络,对生产物流瓶颈转移趋势进行了分析,提出了用MVA近似分析法推算生产物流瓶颈的方法,该方法可以较好地计算瓶颈转折点的数值,能够有效处理生产物流瓶颈转移问题,为提高制造企业生产物流瓶颈管理水平创造了条件。%In this paper, in view of the complexity in removing the logistics bottlenecks in the multi-variety small-batch production system and on the basis of an in-depth analysis of the queue network theory, we established the relationship between the production load and utility rate of different workstations, then in view of the queue network involving two types of work pieces and four workstations, analyzed the trend of the relocation of the bottlenecks in the production logistics system and at last proposed the MVA method to deduct the bottleneck removing process.

  3. 休闲足球运动发展瓶颈问题与对策研究%Research on Developing Bottlenecks and Strategies of Leisure Football

    Institute of Scientific and Technical Information of China (English)

    郑萌

    2015-01-01

    In order to help China’s leisure football develop better, using researching methods including literature and logical analysis, combining with nation environment analysis, sums out the 4 holding back bottlenecks impeding China’s leisure football’s development including limited average resources possession, high threshold of activity participation, social culture value contradiction, insufficient humanity meaning excavation, which causes the prominent problem of low satisfaction of participants’ demands. Comes up with the 2 countermeasures of: to promote school and social education and cultivation to guide and change social culture and demands; to optimize educating and training concepts and means to meet real national environment and social demands. Then implies that the most effective way to guide and change social culture and demands is education and cultivation including: school education and cultivation which mainly run by government administration; social education and cultivation which mainly run by enterprises and markets. This article also implies that the 2 critical points of optimizing educating and training concepts: to optimize teaching methods of techniques and tactics, and to reinforce the excavation of culture connotation. And that the core of optimize educating and training means is to introduce promote modern educating techniques represented by e-educating.%为更好推动我国休闲足球运动发展,运用文献资料、逻辑分析等研究方法,结合国情环境分析,归纳出制约休闲足球运动发展的社会文化价值取向冲突、人文内涵挖掘不足、人均资源占有少、运动参与门槛高等制约瓶颈和由此导致的参与者需求满足能力低等突出问题,提出突破休闲足球运动发展制约瓶颈、解决休闲足球运动发展所面临突出问题的两大对策:推广学校、社会教育培训,引导改变社会文化和需求;改进教育训练理念、手段,适应国情

  4. 广场舞对老年人生活质量的影响与发展瓶颈%A research on the square dance’influence to the old people’s life quality and its bottleneck of development

    Institute of Scientific and Technical Information of China (English)

    邹荣霞; 陈军

    2015-01-01

    对广场舞特点和其产生的影响与发展瓶颈进行分析,建议政府应关心、重视老年人体育文化生活,尽力解决制约广场舞发展的瓶颈;学校和媒体应积极参与,加强社会各界关注,使广场舞健康而快速发展。%The characteristics and the influence of square dance as well as its development bottleneck were described to suggest that the government should take care of and attach importance to sports and cultural life of the elderly,trying to solve the bottleneck restricting the development of square dance. Schools and media should be actively involved in to strengthen the social attention from all walks of life to make the square dance get healthy and rapid development.

  5. Operational Bottlenecks and Countermeasures of House Refuse Logistics System in Great Cities of China%我国大城市生活垃圾物流系统运作瓶颈与对策

    Institute of Scientific and Technical Information of China (English)

    赵长东

    2011-01-01

    Along with the acceleration of urbanization and the increase of urban population of our county, house refuse logistics system in many big cities become difficult to satisfied the increasingly requirements of people's living standard. This article starts from the logistics operation processes of the metropolitan house refuse: collection、 classification、 transportation、 terminal treatment to analyze the bottleneck of the whole operation processes of the house refuse logistics system, and raises the countermeasures to build an efficient logistics system of the municipal solid waste based on this.%随着我国城市化进程的加快,城市人口数量的增加,许多大城市的生活垃圾物流系统难以满足日益提高的人民生活水平要求.本丈从大城市生活垃圾物流的运作流程:收集、分类,运输、末端处理分析了整个垃圾物流系统运作流程瓶颈,并据此提出了建立高效的城市生活垃圾物流系统的对策.

  6. 制约体育社会学研究未能继续深入的瓶颈及其对策分析%Analysis on Bottlenecks and Countermeasures of Sports Sociology Unable to Continue in- depth Research

    Institute of Scientific and Technical Information of China (English)

    祁微

    2011-01-01

    From the viewpoint of Statistical data,the author points out that the bottleneck of sports sociology unable to continue in - depth research is the statistical data and the lack of high - quality issues. After interview with some sports sociology experts, statistical experts and social survey experts, the concept of the sports and content of the census is firstly put forward, and the quality of their data for the assessment is rational considered. The main purpose is to promote the sports sociology of scientific research.%从统计数据的视角,笔者认为制约目前体育社会学研究未能继续深入的瓶颈是统计数据问题。笔者在与一部分体育社会学专家、统计学专家和社会调查学专家的交谈后,首次提出了体育普查的概念和内容,并且对其数据质量的评估进行了理性思考,希望籍此提升体育社会学研究的科学性。

  7. 湖北省民族传统体育基地建设的瓶颈与机遇%About the bottleneck and chance of the national traditional sports base’s building in Hubei province

    Institute of Scientific and Technical Information of China (English)

    张辉

    2015-01-01

    Through the investigation on the current situation of national traditional sports base in Hebei Province , this article finds that the base’s bottlenecks are shortage of funds,insufficient facilities,draining and lacking of talents,and faulty base system etc.. Combined with the special nature of dependency relations between national traditional sports base and the school in Hubei province;and proposes to enrich and perfect the base system,to improve the distribution of bases,to promote the national fitness,government funding and their own income working along both lines, and the base construction and national traditional sports teaching organically combining;then it gives other suggestions for new opportunities of double development of the base and campus culture construction.%通过对湖北省民族传统体育基地的现状调研,发现存在经费紧张、场地设施不足、人才流失与匮乏、基地制度不完善等瓶颈限制。结合湖北省民族传统体育基地与学校依存关系的特殊性,提出丰富和完善基地制度、改善基地分布、促进全民健身、政府拨款与自身创收双管齐下、基地建设与民族传统体育教学有机融合等针对性建议,以期为基地建设与校园文化双重发展的新机遇建言献策。

  8. 科技期刊提升学术质量的若干瓶颈问题及其对策%Few Bottleneck Problems and Solutions in Promoting the Academic Quality of Scientific Journals

    Institute of Scientific and Technical Information of China (English)

    俞祚华

    2011-01-01

    学术质量是科技期刊的立身之本.但科技期刊提升学术质量目前存在着种种阻碍.提出了科技期刊特别是学术型期刊提升学术质量过程中存在的6大瓶颈问题,包括内容上的综合性直接制约影响因子、期刊编辑与科研缺乏融合而形成"源头受阻"、期刊人才队伍建设滞后、学术成果传播速度不快、运营体制机制及手段比较落后、期刊国际化程度低等,并在深入剖析的基础上提出了针对性的对策建议.%Academic quality is the foundation for scientific journals. However, there currently exist various obstacles to promote the academic quality. The paper identifies six major bottleneck problems in promoting academic quality of scientific journals, especially academic scientific journals. The six problems include: the comprehensiveness of the topics directly limits their impact factors; lack of integration among journal editing and scientific research blocks the source of good academic articles; human resource development in academic journals lag behind; research results spread at a low speed; the operation and distribution mechanisms of the journals are relatively outdated; the journals are not globalized enough. The study provides a thorough and insightful analysis, and proposes specific solutions and strategies targeting at the six major problems in promoting the quality of academic journals.

  9. Bottlenecks in the informatization management of small and medium enterprises in Liaoning and solutions%辽宁中小企业信息化管理存在的瓶颈及解决的对策建议

    Institute of Scientific and Technical Information of China (English)

    王明建; 周蓬; 孔鹏

    2012-01-01

    In the 21st century,the rapid development of economic globalization and global informatization made the competition among enterprises more and more intense and in increasing level.With the development of economic globalization,the informatization has become a must of the survival and development of enterprise.Informatization has become the determinants of survival and development,become an important part of business strategy,and been an important way to enhance the competitiveness of enterprises.The paper started from the significance of informatization of the enterprise,the development status and other aspects to analyze the bottlenecks in current informatization of small and medium enterprises and make recommendations and countermeasures.%21世纪全球信息化与经济全球化迅猛发展,竞争层次也越来越高,企业之间的竞争越来越激烈。企业信息化建设,随着经济全球化的发展,已经成为企业生存发展的必经之路。信息化建设已成为企业经营战略的重要内容,成为企业生存与发展的决定因素,是企业提升竞争力的重要途径。从中小企业发展现状及信息化的意义等方面入手,讨论目前中小企业信息化建设存在的瓶颈问题,并提出相关建议及解决对策。

  10. 翻转课堂在我国发展的瓶颈及路向选择%The Bottlenecks and Path Alternatives to Flipped Classroom Development in Our Country

    Institute of Scientific and Technical Information of China (English)

    韩丽珍

    2013-01-01

      翻转课堂作为新兴的教育理念及教学模式,为教师提供个性化教学平台,为学生提供个性化学习空间。学生通过课外的自主学习,课内的协作互动,掌握及内化知识。翻转课堂在我国的发展受固有的传统教育文化、教学条件的制约,有必要对其进行本土化改进,寻找适合我国翻转课堂教学的发展路向。通过对翻转课堂的理念及优势进行论述,深入剖析其在我国发展瓶颈,提出翻转课堂在我国的发展路向。%As the emerging philosophy of education and teaching mode , flipped classroom provides personalized teaching platform for teachers and personalized learning space for students .Students acquire and internalize knowledge through extracurricular au-tonomous learning and collaboration in the classroom .The development of the flipped classroom was restricted by the educational culture of inherent tradition and teaching conditions in our country .So it is necessary to make localization improvements and look for suitable direction of development for the flipped classroom teaching in China .After discussing the idea and advantages of the flipped classroom, and analyzing the bottleneck of its development in China , this paper puts forward direction of development of the flipped classroom in our country .

  11. Document Clustering using Sequential Information Bottleneck Method

    OpenAIRE

    MS. P.J.Gayathri; S.C. Punitha; Dr.M.Punithavalli

    2010-01-01

    Document clustering is a subset of the larger field of data clustering, which borrows concepts from the fields of information retrieval (IR), natural language processing (NLP), and machine learning (ML). It is a more specific technique for unsupervised document organization, automatic topic extraction and fast information retrieval or filtering. There exist a wide variety of unsupervised clustering algorithms. In this paper presents a sequential algorithm for document clustering based with an...

  12. Bottlenecks in Ramping Up Public Investment

    OpenAIRE

    van der Ploeg, Frederick

    2012-01-01

    A windfall in a developing economy with capital scarcity and investment adjustment costs facing a temporary windfall should be used to give more consumption to poorer present generations and to speed up development by ramping up public investment and paying off debt taking due account of the increasing inefficiency as investment gets ramped up. The optimal strategy requires negative genuine saving; the permanent income requires zero genuine saving. The optimal real consumption increments are ...

  13. A bottleneck capital model of development

    OpenAIRE

    Jordan Rappaport

    2002-01-01

    A convex marginal adjustment cost allows the neoclassical growth model to match observed transition paths for output growth, savings, investment, the real interest rate, and the shadow value of installed capital. Such an adjustment cost need apply only to one of two complementary capital inputs with minimal factor income share. The interaction of complementary capital inputs blurs the distinction between capital accumulation and productivity growth.

  14. Crossing the bottleneck of rain formation

    OpenAIRE

    Rohloff, Martin; Lapp, Tobias; Vollmer, Jürgen

    2014-01-01

    The demixing of a binary fluid mixture, under gravity, is a two stage process. Initially droplets, or in general aggregates, grow diffusively by collecting supersaturation from the bulk phase. Subsequently, when the droplets have grown to a size, where their Peclet number is of order unity, buoyancy substantially enhances droplet growth. The dynamics approaches a finite-time singularity where the droplets are removed from the system by precipitation. The two growth regimes are separated by a ...

  15. Colloidal Jamming Dynamics in Microchannel Bottlenecks.

    Science.gov (United States)

    Sendekie, Zenamarkos B; Bacchin, Patrice

    2016-02-16

    The purpose of this work is to examine the interplay between hydrodynamic conditions and physicochemical interactions from filtration experiments of microparticles. Experiments are performed in microfluidic filters with real-time visualization at pore scale. Both flow rate and pressure are measured with time to analyze the dynamics of pore clogging and permeability. Flux stepping experiments are performed at different physicochemical conditions to determine the different clogging conditions. The results allow distinguishing different clogging behaviors according to filtration conditions which are discussed by considering particle-particle and particle-wall colloidal interactions whose main characteristics are an important repulsive barrier at 0.01 mM, a significant secondary minimum at 10 mM, and low repulsive barrier at 100 mM. Clogging delay at moderate ionic strength and deposit fragility and associated sweeping out of aggregates of particles at high ionic strength are discussed from the deposit structure, specific resistance, and deposit relaxation analyses. It has also been observed that an opening angle at microchannel entrance causes rapid clogging, this effect being more pronounced when the repulsion is partially screened. Three different scenarios are discussed by analogy to crowd swarming: panic scenario (0.01 mM) where repulsion between particles induce pushing effects leading to the creation of robust arches at pore entrances; herding instinct scenario (10 mM) where the attraction (in secondary minima) between particles enhances the transport in pores and delays clogging; and sacrifice scenario (100 mM) where the capture efficiency is high but the aggregate formed at the wall is fragile. PMID:26789199

  16. Colloidal Jamming Dynamics in Microchannel Bottlenecks

    OpenAIRE

    Sendekie, Zenamarkos Bantie; Bacchin, Patrice

    2016-01-01

    The purpose of this work is to examine the interplay between hydrodynamic conditions and physicochemical interactions from filtration experiments of microparticles. Experiments are performed in microfluidic filters with real-time visualization at pore scale. Both flow rate and pressure are measured with time to analyze the dynamics of pore clogging and permeability. Flux stepping experiments are performed at different physicochemical conditions to determine the different clogging conditions. ...

  17. EU to tackle trucker bottlenecks / Todd Graham

    Index Scriptorium Estoniae

    Graham, Todd

    2006-01-01

    Läti peaminister Aigars Kalvitis ütles Euroopa Komisjonis, et veoautode järjekorra probleem piiril on ka Euroopa ühine mure. Ainult Venemaa tolli olukorras süüdistada ei saa. Tabel: Trucks on the border

  18. Optimization of Energy Storage System Capacity for Relaxing Peak Load Regulation Bottlenecks%用于松弛调峰瓶颈的储能系统容量配置方法

    Institute of Scientific and Technical Information of China (English)

    严干贵; 冯晓东; 李军徽; 穆钢; 谢国强; 董效辰; 王芝茗; 杨凯

    2012-01-01

    利用大规模电池储能系统对电网负荷“削峰填谷”,减少日负荷波动幅度,可以缓解发电机组对负荷追踪调控负担,使电网具备更多向下调节容量来接纳风电.基于给定的负荷特性,分析储能系统配置容量与其改善负荷波动水平之间的关系,以储能系统投资成本、经济效益为约束,以综合效益最大为目标,提出一种用于松弛调峰瓶颈的大规模储能系统容量优化配置方法.针对2010年某省电网接纳风电受限现状,利用该方法对其进行改善,分析了储能系统运行年限、投资成本对其容量配置的影响,算例结果验证了所提出方法的可行性.%Using large-scale battery energy storage systems for load shifting and peak smoothing can decrease the fluctuation of daily load and reduce load tracking regulation burden of generator units, and enlarge down-regulate space to accommodate wind power. Based on a given load characteristics, the relationship between the energy storage system allocation capacity and improvement of load fluctuations was analyzed. By making energy storage system's investment costs and economic benefits as constraints, and by maximizing the comprehensive benefits as the object, an optimal capacity-allocation method was proposed for large-scale energy storage systems to relax peak-regulation bottleneck. For the limitation of wind power accommodation of a province in China in 2010, the method was applied to improve the situation and the impact of the life cycle and investment cost of the energy storage system on its capacity configuration. Case study results verified the feasibility of the proposed method.

  19. 成人高等教育学生就业瓶颈探析——基于公共政策执行视角%Analysis of Employment Bottleneck for Students of Adult Higher Education ——Based on Perspective of Pub|ie Policy Implementation

    Institute of Scientific and Technical Information of China (English)

    韦仕祺

    2012-01-01

    Currently the employment for graduate students of aduh higher education is far from optimistic and the designing bottleneck in the system leads to one of the main difficulties in the employment, the reason of which is due to the deviation existing in the design of the system in the public policy and also the deviation can be caused by people who carry out the policy, leading to double psychological worries about learning at school and employment after graduation for adult students. The article tries to analyze the reason of employment bottleneck for students of adult education from the perspective of public policy and on this basis to explore some countermeasures and recommendations on fairness in employment supported by the policy.%当前成人高等教育毕业学生的就业状况不容乐观,究其原因是公共政策存在着制度设计上的偏差,同时人为地制造政策执行的偏差也引起了成人教育学生在校学习与毕业就业压力双重心理的担忧。本文从公共政策执行视角分析成人教育学生就业瓶颈的症结所在,并在此基础上提出成人教育学生获得政策公平就业对待的对策建议。

  20. Research and Development Status and the Bottleneck Breakthrough Ideas of 3D Printing Technology and Orthopaedic Implants%3D 打印技术与骨科植入物研发现状及其瓶颈突破思路

    Institute of Scientific and Technical Information of China (English)

    汤啸天; 王燎

    2015-01-01

    Implants are the core elements of skeletal muscle treatment system with enormous social and eco-nomic effects. The localized and individualized demand for orthopaedic implants forced its research and develop-ment work. In the research field of orthopedic implants, the way for clinical application of 3D printing technology has been paved, and the research and development of orthopaedic implants based on 3D printing technology need legal guarantee. Individualized production is the advantage of 3D printing and the bottleneck of legal restrictions as well, so reform and innovation are needed to break through its application bottleneck. And the following are the solutions to the problems in individualized production of medical equipments by 3D printing technology: 1. Submit to the National Food and Drug Administration for approval of setting up 3D printing pilot clinical application in Shanghai; 2. Suggest signing Consensus Memorandum of Cooperation to prevent common risks; 3. Suggest devel-oping special accident insurance to promote science and technology innovation.%植入物是骨肌系统治疗的核心要素,其社会及经济影响巨大。骨科植入物国产化及个体化需求倒逼研发工作;在骨科植入物研究领域中,3D 打印技术的临床应用已经铺平了道路,基于3D 打印技术的骨科植入物研发亟待法治化保障。个体化生产是3D 打印技术的优势也是法律限制的瓶颈,需改革创新方能突破3D 打印技术医疗应用瓶颈。破解3D 打印技术个体化生产医疗器械难题的思路:第一,报请国家食药监局批准在上海建立3D 打印技术临床应用试点;第二,建议签署《合作共识备忘录》共同防范风险;第三,建议开发特殊意外保险推进科学技术创新。

  1. Expansion of biowaste collection as a means of resolving capacity bottlenecks in residual waste treatment - new incentives from the Landfill Ordinance and the Renewable Energy Law; Ausweitung der Bioabfallerfassung als Massnahme zur Loesung von Kapazitaetsengpaessen bei der Restabfallbehandlung - AbfAblV und EEG schaffen neue Anreize

    Energy Technology Data Exchange (ETDEWEB)

    Kern, M. [Witzenhausen-Institut fuer Abfall, Unwelt und Energie GmbH (Germany)

    2006-07-01

    One year after the enactment of the Landfill Ordinance the German Federal Environment Ministry sees no alleviation of Germany's shortage of waste disposal capacities. According to the Laender Working Group on Wastes (LAGA) some 1.2 mil. Mg of high-caloric and untreated wastes distributed over more than 70 interim stores currently await final disposal (EUWID, 2006). The Federal Ministry for Environment, Nature Conservation and Reactor Safety (BMU) has stated that in mid-2006 ca. 16.3 mil. Mg of waste incineration capacity and ca. 5.5 mil. Mg of mechanical biological waste treatment capacity were available. The forecast 2.3 mil. Mg of mono-/co-combustion capacity have not been reached so far. At the same time Germany has substantial unused capacity for biological waste treatment. This brings to one's mind the obvious idea of expanding the collection of biowastes, thus also easing the bottleneck in residual waste disposal. This notion gains all the more significance as many municipalities run their biowaste collection system suboptimally or have none in place at all. The present article documents arisings and available waste treatment capacities for biowaste and green waste and points out new utilisation options, particularly with a mind to the German Renewable Energy Law.

  2. Communities and bottlenecks: trees and treelike networks have high modularity.

    Science.gov (United States)

    Bagrow, James P

    2012-06-01

    Much effort has gone into understanding the modular nature of complex networks. Communities, also known as clusters or modules, are typically considered to be densely interconnected groups of nodes that are only sparsely connected to other groups in the network. Discovering high quality communities is a difficult and important problem in a number of areas. The most popular approach is the objective function known as modularity, used both to discover communities and to measure their strength. To understand the modular structure of networks it is then crucial to know how such functions evaluate different topologies, what features they account for, and what implicit assumptions they may make. We show that trees and treelike networks can have unexpectedly and often arbitrarily high values of modularity. This is surprising since trees are maximally sparse connected graphs and are not typically considered to possess modular structure, yet the nonlocal null model used by modularity assigns low probabilities, and thus high significance, to the densities of these sparse tree communities. We further study the practical performance of popular methods on model trees and on a genealogical data set and find that the discovered communities also have very high modularity, often approaching its maximum value. Statistical tests reveal the communities in trees to be significant, in contrast with known results for partitions of sparse, random graphs. PMID:23005173

  3. Larynx during exercise: the unexplored bottleneck of the airways

    OpenAIRE

    2014-01-01

    Exercise-induced shortness of breath is not uncommon in otherwise healthy young people. Based on the presenting symptoms alone, it is challenging to distinguish exercise-induced asthma (EIA) from exercise-induced obstruction of central airways, sometimes leading to diagnostic errors and inadequate treatment. Central airway obstruction usually presents with exercise-induced inspiratory symptoms (EIIS) during ongoing exercise. EIIS tends to peak towards the end of an exercise session or immedia...

  4. Human-Machine CRFs for Identifying Bottlenecks in Scene Understanding.

    Science.gov (United States)

    Mottaghi, Roozbeh; Fidler, Sanja; Yuille, Alan; Urtasun, Raquel; Parikh, Devi

    2016-01-01

    Recent trends in image understanding have pushed for scene understanding models that jointly reason about various tasks such as object detection, scene recognition, shape analysis, contextual reasoning, and local appearance based classifiers. In this work, we are interested in understanding the roles of these different tasks in improved scene understanding, in particular semantic segmentation, object detection and scene recognition. Towards this goal, we "plug-in" human subjects for each of the various components in a conditional random field model. Comparisons among various hybrid human-machine CRFs give us indications of how much "head room" there is to improve scene understanding by focusing research efforts on various individual tasks. PMID:26656579

  5. Using file system virtualization to avoid metadata bottlenecks

    OpenAIRE

    Artiaga Amouroux, Ernest; Cortés Rosselló, Antonio

    2010-01-01

    Abstract—Parallel file systems are very sensitive to adverse conditions, and the lack of synergy between such file systems and some of the applications running on them has a negative impact on the overall system performance. Our observations indicate that the increased pressure on metadata management is one of the relevant causes of performance drops. This paper proposes a virtualization layer above the native file system that, transparently to the user, reorganizes the underlying di...

  6. Bottlenecks to Clinical Translation of Direct Brain-Computer Interfaces

    Directory of Open Access Journals (Sweden)

    Mijail Demian Serruya

    2014-12-01

    Full Text Available Despite several decades of research into novel brain-implantable devices to treat a range of diseases, only two- cochlear implants for sensorineural hearing loss and deep brain stimulation for movement disorders- have yielded any appreciable clinical benefit. Obstacles to translation include technical factors (e.g., signal loss due to gliosis or micromotion, lack of awareness of current clinical options for patients that the new therapy must outperform, traversing between federal and corporate funding needed to support clinical trials, and insufficient management expertise. This commentary reviews these obstacles preventing the translation of promising new neurotechnologies into clinical application and suggests some principles that interdisciplinary teams in academia and industry could adopt to enhance their chances of success.

  7. Solar energy: state of the art, technological bottlenecks

    International Nuclear Information System (INIS)

    First Japan then Germany and now most westernized countries have put into effect measures and regulations favoring the development of solar energy and solar industry. Today solar energy is full fledged and is engaged into a race toward lower costs and better performance. The study shows that if the pace of progress is maintained solar energy will be competitive by 2020. This evolution will rely more on a continuous flux of innovations than on a series of abrupt technological breakthroughs. (A.C.)

  8. Paradigm shift in transport legislation or rather at the 'bottleneck'

    International Nuclear Information System (INIS)

    In the year just started significant decisions with considerable consequences by the Federal Constitutional Court and the Federal Administrative Court in the field of nuclear law are expected. Especially the decision with regards to 'nuclear phase-out' within the 13th amendment of the Atomic Energy Act is being eagerly expected, as with its far-reaching consequences also fundamental constitutional questions need to be answered. The Federal Administrative Court will need to decide on the question, whether she admits the appeal against the Brunsbuettel decision by the Higher Administrative Court Schleswig-Holstein (HAC), which from the view of claimant shifted the fundamental basis of demarcation of responsibilities between the executive and judiciary power. In comparison to these fundamental decisions the awaited decision by the HAC on nuclear transport legislation seems of subordinate importance, although she will proceed with a paradigm shift in the legal area. The decision deals with the question as to whether and when a right of action from a third party within the nuclear transport legislation can be accepted or more precisely under which preconditions a third party has clear standing against a nuclear transport authorisation. As the site selection law (issued on 23 July 2013 BGBI I p. 2552) excludes the recirculation of vitrified waste block canisters from reprocessing spent fuel elements to the transport cask storage facility Gorleben, the decision by the HAC Lueneburg for this site will only be relevant for present unpredictable transportations from the transport cask storage facility Gorleben to a final repository. If necessary interest to seek a declaratory judgment for declaratory action, in concreto danger of recurrence will be approved, is another matter.

  9. Bacteria Delay the Jamming of Particles at Microchannel Bottlenecks.

    Science.gov (United States)

    Sendekie, Zenamarkos Bantie; Gaveau, Arthur; Lammertink, Rob G H; Bacchin, Patrice

    2016-01-01

    Clogging of channels by complex systems such as mixtures of colloidal and biological particles is commonly encountered in different applications. In this work, we analyze and compare the clogging mechanisms and dynamics by pure and mixture suspensions of polystyrene latex particles and Escherichia coli by coupling fluorescent microscopic observation and dynamic permeability measurements in microfluidic filters. Pure particles filtration leads to arches and deposit formation in the upstream side of the microfilter while pure bacteria form streamers in the downstream zone. When mixing particle and bacteria, an unexpected phenomenon occurs: the clogging dynamics is significantly delayed. This phenomenon is related to apparent "slippery" interactions between the particles and the bacteria. These interactions limit the arches formation at the channels entrances and favour the formation of dendritic structures on the pillars between the channels. When these dendrites are eroded by the flow, fragments of the deposit are dragged towards the channels entrances. However, these bacteria/particles clusters being lubricated by the slippery interactions are deformed and stretched by the shear thus facilitating their passage through the microchannels. PMID:27510611

  10. The planning flexibility bottleneck in food processing industries

    NARCIS (Netherlands)

    van Wezel, W.M.C.; van Donk, D.P.; Gaalman, G.J.C.

    2006-01-01

    Production planners in food processing industries must continuously balance efficient production with flexible performance. On the basis of case studies, we state that flexibility is not only restrained by hard-wired production process characteristics, but also by organizational procedures in the pl

  11. Personalized Medicine’s Bottleneck: Diagnostic Test Evidence and Reimbursement

    Directory of Open Access Journals (Sweden)

    Joshua P. Cohen

    2014-04-01

    Full Text Available Background: Personalized medicine is gradually emerging as a transformative field. Thus far, seven co-developed drug-diagnostic combinations have been approved and several dozen post-hoc drug-diagnostic combinations (diagnostic approved after the drug. However, barriers remain, particularly with respect to reimbursement. Purpose, methods: This study analyzes barriers facing uptake of drug-diagnostic combinations. We examine Medicare reimbursement in the U.S. of 10 drug-diagnostic combinations on the basis of a formulary review and a survey. Findings: We found that payers reimburse all 10 drugs, but with variable and relatively high patient co-insurance, as well as imposition of formulary restrictions. Payer reimbursement of companion diagnostics is limited and highly variable. In addition, we found that the body of evidence on the clinical- and cost-effectiveness of therapeutics is thin and even less robust for diagnostics. Conclusions, discussion: The high cost of personalized therapeutics and dearth of evidence concerning the comparative clinical effectiveness of drug-diagnostic combinations appear to contribute to high patient cost sharing, imposition of formulary restrictions, and limited and variable reimbursement of companion diagnostics. Our findings point to the need to increase the evidence base supportive of establishing linkage between diagnostic testing and positive health outcomes.

  12. Inverse bottleneck in Eu2+-Mn2+ energy transfer

    International Nuclear Information System (INIS)

    The energy transfer (ET) between Eu2+ and Mn2+ in Ca5(PO4)3Cl has been investigated. At low intensities under 405 nm excitation, time-resolved experiments provide microscopic parameters for the energy transfer between adjacent Eu2+ and Mn2+ ions. At high intensities, we observe a non-linear component in the energy transfer process due to ground state depletion of the Mn2+ ions, leading not to a reduction, but to an increase in the energy transfer rate between Eu2+ and Mn2+ ions and also energy transfer between excited Mn2+ ions. This results in a sub-linear response of both Eu2+ and Mn2+ luminescence as a function of intensity. Our observations are quantitatively described by a model using energy transfer to Mn2+ ions in both the ground and the excited state.

  13. A CAPACITY EXPANSION PROBLEM WITHBUDGET CONSTRAINT AND BOTTLENECK LIMITATION

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper considers a capacity expansion problem with budget constraint.Suppose each edge in the network has two attributes: capacity and the degree of difficulty.The difficulty degree of a tree T is the maximum degree of difficulty of all edges in the tree and the cost for coping with the difficulty in a tree is a nondecreasing function about the difficulty degree of the tree. The authors need to increase capacities of some edges so that there is a spanning tree whose capacity can be increased to the maximum extent.meanwhile the total cost for increasing capacity as well as overcoming the difficulty in the spanning tree does not exceed a given budget D*. Suppose the cost for increasing capacity on each edge is a linear function about the increment of capacity, they transform this problem into solving some hybrid parametric spanning tree problems[1] and propose a strongly polynomial algorithm.

  14. [Dealing with bottlenecks in health care: legal implications].

    Science.gov (United States)

    Katzenmeier, Christian

    2010-01-01

    Scarcity in the German health care system leads to an implicit allocation of means and also implies a risk of liability for physicians. Prioritisation can contribute to the solution of these problems and ascertain an equitable allocation of scarce resources. However, the criteria that will be applied to establish a ranking order will have to be thoroughly considered, particularly in light of the constitutional law, and there is still a multitude of unresolved questions seeking an answer. This requires an open political discourse about society and health care. PMID:20870484

  15. Spurious Products: A Bottleneck in Growth and Development

    OpenAIRE

    Nanda, Ch Siddharth; Kantha, Dr. Ranjan Kumar

    2015-01-01

    Creativity and innovation are proven factors for economic growth and competitive advantage. In this cut throat competition being a first mover backed with innovative offerings will for sure create a blue ocean. However as the competition gets fierce it becomes imperative for organizations to not only be creative and innovative but also tune its offerings according to consumer requirements. As the consumer is emerging as the ultimate decider for the success of a product, creating and susta...

  16. Squeezing bottlenecks: exploring the limits of autoencoder semantic representation capabilities

    OpenAIRE

    Gupta, Parth; Banchs, Rafael E.; Rosso, Paolo

    2014-01-01

    We present a comprehensive study on the use of autoencoders for modelling text data, in which (differently from previous studies) we focus our attention on the following issues: i) we explore the suitability of two different models bDA and rsDA for constructing deep autoencoders for text data at the sentence level; ii) we propose and evaluate two novel metrics for better assessing the text-reconstruction capabilities of autoencoders; and iii) we propose an automatic method to find the critica...

  17. Bottlenecks for metabolic engineering of isoflavone glycoconjugates in Arabidopsis

    OpenAIRE

    Liu, Chang-Jun; Blount, Jack W.; Steele, Christopher L.; Dixon, Richard A.

    2002-01-01

    In view of their perceived chemopreventive activities against hormone-dependent cancers, cardiovascular disease, and postmenopausal ailments, there is considerable interest in engineering plants to contain isoflavone phytoestrogens. However, attempts to date have only resulted in low levels of isoflavone accumulation in non-legumes. Introducing soybean isoflavone synthase (IFS) into Arabidopsis thaliana leads to accumulation of low levels of genistein glycosides. Leaves of wild-type A. thalia...

  18. Landscape modelling spatial bottlenecks: implications for raccoon rabies disease spread

    OpenAIRE

    Rees, Erin E; Pond, Bruce A.; Cullingham, Catherine I; Tinline, Rowland R.; Ball, David; Kyle, Christopher J.; White, Bradley N

    2009-01-01

    A landscape genetic simulation modelling approach is used to understand factors affecting raccoon rabies disease spread in southern Ontario, Canada. Using the Ontario Rabies Model, we test the hypothesis that landscape configuration (shape of available habitat) affects dispersal, as indicated by genetic structuring. We simulated range expansions of raccoons from New York into vacant landscapes in Ontario, in two areas that differed by the presence or absence of a landscape constriction. Our r...

  19. Teacher Diversity in Canada: Leaky Pipelines, Bottlenecks, and Glass Ceilings

    Science.gov (United States)

    Ryan, James; Pollock, Katina; Antonelli, Fab

    2009-01-01

    This article examines the racial diversity of the teacher population in Canada. In particular, we compare the number of teachers of colour in Canadian elementary and secondary schools from the 2001 and 2006 Census data with the diversity of the student and general populations. We also explore ways to understand the gap between the proportion of…

  20. Bottlenecks in Software Defect Prediction Implementation in Industrial Projects

    Directory of Open Access Journals (Sweden)

    Hryszko Jarosław

    2015-03-01

    Full Text Available Case studies focused on software defect prediction in real, industrial software development projects are extremely rare. We report on dedicated R&D project established in cooperation between Wroclaw University of Technology and one of the leading automotive software development companies to research possibilities of introduction of software defect prediction using an open source, extensible software measurement and defect prediction framework called DePress (Defect Prediction in Software Systems the authors are involved in. In the first stage of the R&D project, we verified what kind of problems can be encountered. This work summarizes results of that phase.

  1. Is follow-up capacity the current NHS bottleneck?

    Science.gov (United States)

    Allder, Steven; Walley, Paul; Silvester, Kate

    2011-02-01

    Capacity and demand theory suggests that the presence of a queue is not necessarily an indication of a shortage of capacity in a system. It is much more likely that either there is a demand and capacity variation that creates queues or there is a delay designed into the system. A shortage of capacity is only really indicated where a backlog is not stable and continues to grow. In this article, data are taken from one NHS trust that provides evidence for a continually growing backlog for follow-up outpatient services. It is believed that these data are representative of most locations within the NHS in England and therefore suggest an immediate shortage in effective follow-up capacity. To avoid compromise to patient care, the problem will have to be addressed before the situation becomes unmanageable. The paper highlights options to reduce or deflect demand or to increase effective capacity. PMID:21404781

  2. Invited review: Clogging of granular materials in bottlenecks

    OpenAIRE

    Iker Zuriguel

    2014-01-01

    During the past decades, notable improvements have been achieved in the understanding of static and dynamic properties of granular materials, giving rise to appealing new concepts like jamming, force chains, non-local rheology or the inertial number. The 'saltcellar' can be seen as a canonical example of the characteristic features displayed by granular materials: an apparently smooth flow is interrupted by the formation of a mesoscopic structure (arch) above the outlet that causes a quick di...

  3. Invited review: Clogging of granular materials in bottlenecks

    Directory of Open Access Journals (Sweden)

    Iker Zuriguel

    2014-12-01

    Full Text Available During the past decades, notable improvements have been achieved in the understanding of static and dynamic properties of granular materials, giving rise to appealing new concepts like jamming, force chains, non-local rheology or the inertial number. The 'saltcellar' can be seen as a canonical example of the characteristic features displayed by granular materials: an apparently smooth flow is interrupted by the formation of a mesoscopic structure (arch above the outlet that causes a quick dissipation of all the kinetic energy within the system. In this manuscript, I will give an overview of this field paying special attention to the features of statistical distributions appearing in the clogging and unclogging processes. These distributions are essential to understand the problem and allow subsequent study of topics such as the influence of particle shape, the structure of the clogging arches and the possible existence of a critical outlet size above which the outpouring will never stop. I shall finally offer some hints about general ideas that can be explored in the next few years.

  4. Expectational Bottlenecks and the Emerging of New Organizational Forms

    OpenAIRE

    Rampa, Giorgio; Bogliacino, Francesco

    2012-01-01

    In this article we discuss the dynamics of organizational change when agents have heterogeneous initial conjectures and do learn. In this framework, conjectural equilibrium is defined as a steady state of the learning process, and all the adjustment occurs in disequilibrium. We discuss the properties of the system under different “rationality” assumptions, and using well-known learning algorithms. We prove analytically that multiplicity of equilibria, and failure of good organizational routin...

  5. Breaking the biomass bottleneck of the fossil free society

    OpenAIRE

    Wenzel, Henrik

    2010-01-01

    The focus on global warming and security of resource supply has led many sectors in society to look for alternatives to oil and other fossil resources. Biological resources – biomass in brief – is at present a preferred alternative in many sectors of society. Biomass is, thus, in growing demand for heat and power services as well as for transportation fuels and as feedstock for chemicals and materials – i.e. in practice all sectors today being dependant on fossil fuels. At the same time, unfo...

  6. Larynx during exercise: the unexplored bottleneck of the airways.

    Science.gov (United States)

    Røksund, Ola Drange; Heimdal, John-Helge; Olofsson, Jan; Maat, Robert Christiaan; Halvorsen, Thomas

    2015-09-01

    Exercise-induced shortness of breath is not uncommon in otherwise healthy young people. Based on the presenting symptoms alone, it is challenging to distinguish exercise-induced asthma (EIA) from exercise-induced obstruction of central airways, sometimes leading to diagnostic errors and inadequate treatment. Central airway obstruction usually presents with exercise-induced inspiratory symptoms (EIIS) during ongoing exercise. EIIS tends to peak towards the end of an exercise session or immediately after its completion, contradicting symptoms of EIA typically peaking 3-15 min after the exercise has stopped. EIIS is usually associated with some form of laryngeal obstruction. Transnasal flexible laryngoscopy performed continuously throughout an incremental exercise test from rest to exhaustion or to intolerable symptoms is usually diagnostic, and also provides information that is important for further handling and treatment. Reflecting the complex anatomy and functional features of the larynx, exercise-induced laryngeal obstruction (EILO) appears to be a heterogeneous condition. Contradicting previous beliefs, recent literature suggests that laryngeal adduction in a majority of cases starts in supraglottic structures and that vocal cord adduction (VCD) most often occurs as a secondary phenomenon. However, EILO is poorly understood and more and better research is needed to unravel causal mechanisms. The evidence base for treatment of EILO is weak. Speech therapy, psychotherapy, biofeedback, muscle training, anticholinergic aerosols have all been applied, as has laser supraglottoplasty. Randomized controlled trials with well-defined and verifiable inclusion and success criteria are required to establish evidence-based treatment schemes. PMID:25033930

  7. Intelligent Automated Diagnosis of Client Device Bottlenecks in Private Clouds

    CERN Document Server

    Widanapathirana, C; Sekercioglu, Y A; Ivanovich, M; Fitzpatrick, P; 10.1109/UCC.2011.42

    2012-01-01

    We present an automated solution for rapid diagnosis of client device problems in private cloud environments: the Intelligent Automated Client Diagnostic (IACD) system. Clients are diagnosed with the aid of Transmission Control Protocol (TCP) packet traces, by (i) observation of anomalous artifacts occurring as a result of each fault and (ii) subsequent use of the inference capabilities of soft-margin Support Vector Machine (SVM) classifiers. The IACD system features a modular design and is extendible to new faults, with detection capability unaffected by the TCP variant used at the client. Experimental evaluation of the IACD system in a controlled environment demonstrated an overall diagnostic accuracy of 98%.

  8. The"bottlenecks"and Solutions of Enterprise Skilled Personnel---Based on the Survey of 363 enterprises in Chongqing%企业技能人才队伍“瓶颈”制约及解决对策--基于重庆市363家企业的调查

    Institute of Scientific and Technical Information of China (English)

    李志; 邱萍; 蒋雨珈

    2015-01-01

    采用文献分析、问卷调查以及访谈法对重庆市363家不同性质企业的技能人才队伍状况进行了实证调查。研究发现,企业技能人才队伍存在以下“瓶颈”:多数企业技能人才数量短缺,素质不高;企业重视技能人才开发,但培训效果不理想;企业技能人才稳定性差,新员工招聘困难;企业缺乏系统的非物质激励体系,技能人才发展缺乏内在动力;与国有企业相比,民营企业的技能人才队伍存在明显劣势。在此基础上,结合国内外其它地区技能人才队伍建设先进经验,提出了加强企业技能人才队伍建设的对策建议。%Skilled personnel have an important significance for the long‐term development of enterprises .The paper con‐ducts an empirical investigation on the qualified personnel in 363 companies of Chong Qing through the literature analysis , questionnaires and interviews .It was found that there are some following "bottlenecks" in the corporate skilled team building :(1) Most companies do not have the high quality and insufficient number of skilled personnel ;(2) Enterprises attach importance to the skills training ,but the effect is not ideal ;(3) The skilled personnel in the Enterprise are poor sta‐bility and the recruitment of the new staff is very difficult ;(4) Enterprises lack a systematic incentive system to match the needs of the skilled personnel ;(5) Compared with the state‐owned enterprises ,the skilled personnel of private enterprises has an obvious disadvantage .On the basis of above mentioned ,it proposes the countermeasures to strengthen the entre‐preneurial skills of qualified personnel combined with the skilled team building in advanced experience of other regions at home and abroad .

  9. Are communities just bottlenecks? Trees and treelike networks have high modularity

    CERN Document Server

    Bagrow, James P

    2012-01-01

    Much effort has gone into understanding the modular nature of complex networks. Communities, also known as clusters or modules, are densely interconnected groups of nodes that are only sparsely connected to other groups in the network. Discovering high quality communities is a difficult and important problem in a number of areas. The most popular approach is the objective function known as Modularity, used to both discover communities and measure their strength. To understand the modular structure of networks it is then crucial to know how such functions evaluate different topologies, what features they account for and what implicit assumptions they may make. We show that trees and treelike networks can have unexpectedly and often arbitrarily high values of modularity. This is surprising since trees are maximally sparse connected graphs and are not typically considered to possess modular structure, yet the non-local null model used by modularity assigns low probabilities, and thus high significance, to the de...

  10. Bottleneck Analysis on the DoD Pre-Milestone B Acquisition Processes

    OpenAIRE

    Worger, Danielle; Wu, Teresa; Jalao, Eugene Rex; Auger, Christopher; Baldus, Lars; Yoshimoto, Brian; Wirthlin, J. Robert; Colombi, John

    2013-01-01

    Excerpt from the Proceedings of the Tenth Annual Acquisition Research Symposium Acquisition Management Disclaimer: The views represented in this report are those of the authors and do not reflect the official policy position of the Navy, the Department of Defense, or the federal government. The research presented in this report was supported by the Acquisition Research Program of the Graduate School of Business & Public Policy at the Naval Postgraduate School. To request defens...

  11. Solid-Set Sprinkler Irrigation Controllers Driven by Simulation Models: Opportunities and Bottlenecks

    OpenAIRE

    Playán Jubillar, Enrique; Salvador Esteban, Raquel; López Marín, Cristina; Lecina Brau, Sergio; Dechmi, Farida; Zapata Ruiz, Nery

    2013-01-01

    Farmers continue to show great differences in irrigation water use, even for a given location and crop. Irrigation advisory services have narrowed the gap between scientific knowledge and on-farm scheduling, but their success has been limited. The performance of sprinkler irrigation is greatly affected by factors such as wind speed, whose short-time variability requires tactical adjustments of the irrigation schedule. Mounting energy costs often require the consideration of interday and intra...

  12. Pushing away the communication bottleneck with optical interconnects in symmetric multiprocessors

    Science.gov (United States)

    Hlayhel, Wissam; Collet, Jacques H.; Rochange, Christine; Litaize, Daniel

    2000-05-01

    We analyze the bandwidth needed for transmitting the addresses in future symmetric multiprocessor machines (SMP), constructed around a shared bus due to the critical obligation to preserve the coherence of the memory hierarchy. We show that an address-transaction bandwidth as high as several hundreds of Gbit/s will be necessary not to slow down the execution of most applications in large SMP's. This communication bandwidth seems incompatible with the operation constraints of shared electrical busses, making necessary the search for other implementations of the address transmission network. We consider the introduction of optical interconnects (OI) in this context. We review several solutions, in the ascending order of complexity of the optical subsystems as one critical issue concerns the degree of sophistication of the optical solutions and their cost. We first consider simple point to point OI's for a SMP chipset. The interest for OI's comes from the low energy consumption and from the possibility, in the future, to integrate several thousands of optical input/outputs per electronic chip. The we consider the implementation of an optical bus that is a multipoint optical line involving more optical functionality. We discuss the possibility of multiple accesses to the bus, and the constraints related to the necessity to maintain the coherence of caches.

  13. Steiner tree heuristic in the Euclidean d-space using bottleneck distances

    DEFF Research Database (Denmark)

    Lorenzen, Stephan Sloth; Winter, Pawel

    2016-01-01

    Some of the most efficient heuristics for the Euclidean Steiner minimal tree problem in the d-dimensional space, d ≥2, use Delaunay tessellations and minimum spanning trees to determine small subsets of geometrically close terminals. Their low-cost Steiner trees are determined and concatenated in a...

  14. HDMI:the Future and Bottlenecks%HDMI:前景与瓶颈并存

    Institute of Scientific and Technical Information of China (English)

    刘洋

    2007-01-01

    HDMI (High-Definition Multimedia Interface)目前似乎是市场上消费电子产品数字视频接口传输标准最流行的一种,其通过一根电缆即可传输高质量的音频和视频信号,预计到2010年,HDMI设备将超过100亿件,最新的HDMI 1.8标准提供两倍的带宽,从而可以舆更高质量的音频和视频信号,显示色觉提高到48bit,能展现更多的色彩和层次,音频的传输也达到7.1声道.

  15. Development of a Workbench to Address the Educational Data Mining Bottleneck

    Science.gov (United States)

    Rodrigo, Ma. Mercedes T.; Baker, Ryan S. J. d.; McLaren, Bruce M.; Jayme, Alejandra; Dy, Thomas T.

    2012-01-01

    In recent years, machine-learning software packages have made it easier for educational data mining researchers to create real-time detectors of cognitive skill as well as of metacognitive and motivational behavior that can be used to improve student learning. However, there remain challenges to overcome for these methods to become available to…

  16. The potential risks from metals bottlenecks to the deployment of Strategic Energy Technologies

    International Nuclear Information System (INIS)

    This paper examines the use of materials, in particular metals, in six low-carbon energy technologies of the European Union's Strategic Energy Technology Plan (SET-Plan), namely nuclear, solar, wind, bioenergy, carbon capture and storage and electricity grids. The projected average annual demand for metals in the SET-Plan technologies for the decades up to 2020 and 2030 is compared to the known global production volume in 2010. From an initial inventory of over 50 metals, 14 metals were identified that will require 1% or more of the 2010 world supply per annum between 2020 and 2030. These 14 metals are cadmium, dysprosium, gallium, hafnium, indium, molybdenum, neodymium, nickel, niobium, selenium, silver, tellurium, tin and vanadium. These metals were examined further by analysing the effect of market and geo-political factors of supply and demand, which highlighted five metals to represent a high risk to large-scale technology deployment, namely: neodymium, dysprosium, indium, tellurium and gallium. The five metals were further analysed with respect to the wind and solar sectors, showing that the demand of these metals could increase significantly depending on future sub-technology choices. Mitigation strategies to alleviate potential shortages are also discussed, e.g. extending primary output; re-use, re-cycling and waste reduction; and substitution. - Highlights: ► Over 50 metals and their usage in six low-carbon energy technologies are analysed. ► 14 metals are identified that will require 1% or more of the 2010 world supply per annum. ► The 14 metals are further examined with respect to market and geo-political factors. ► 5 metals Nd, Dy, In, Te and Ga are a high risk to large-scale technology deployment. ► Demand for the 5 metals increases for sub-technology choices in PV and wind energy

  17. Experimental proof of Faster-is-Slower in multi-particle systems flowing through bottlenecks

    CERN Document Server

    Pastor, José M; Gago, Paula A; Peralta, Juan P; Martín-Gómez, César; Ferrer, Luis M; Maza, Diego; Parisi, Daniel R; Pugnaloni, Luis A; Zuriguel, Iker

    2015-01-01

    The "faster-is-slower" (FIS) effect was first predicted by computer simulations of the egress of pedestrians through a narrow exit [Helbing D, Farkas I J, Vicsek T, Nature 407:487-490 (2000)]. FIS refers to the finding that, under certain conditions, an excess of the individuals' vigor in the attempt to exit causes a decrease in the flow rate. In general, this effect is identified by the appearance of a minimum when plotting the total evacuation time of a crowd as a function of the pedestrian desired velocity. Here, we experimentally show that the FIS effect indeed occurs in three different systems of discrete particles flowing through a constriction: (a) humans evacuating a room, (b) a herd of sheep entering a barn and (c) grains flowing out a 2D hopper over a vibrated incline. This finding suggests that FIS is a universal phenomenon for active matter passing through a narrowing.

  18. Migration of health workers in the Pacific Islands: a bottleneck to health development.

    Science.gov (United States)

    Yamamoto, T S; Sunguya, B F; Shiao, L W; Amiya, R M; Saw, Y M; Jimba, M

    2012-07-01

    Human resources for health (HRH) are a crucial component of a well-functioning health system. Problems in the global HRH supply and distribution are an obstacle to achieving the health-related Millennium Development Goals and other health outcomes. The Pacific Island region, covering 20,000 to 30,000 islands in the South Pacific Ocean, is suffering a serious HRH crisis. Yet updated evidence and data are not available for the 22 Pacific Island Countries and Territories. The objective of this study was thus to explore the current HRH situation in the Pacific Island region, focusing particularly on the issue of health workforce migration. HRH trends and gaps differ by country, with some showing increases in HRH density over the past 20 years whereas others have made negligible progress. Currently, three Pacific Island countries are facing critical HRH shortages, a worsening of the situation from 2006, when HRH issues were first brought to widespread global attention. In this region, skilled personnel migration is a major issue contributing to the limited availability of HRH. Political commitment from source and destination countries to strengthen HRH would be a key factor toward increasing efforts to train new health personnel and to implement effective retention strategies. PMID:22815302

  19. Impact of population structure, effective bottleneck time, and allele frequency on linkage disequilibrium maps

    OpenAIRE

    Zhang, Weihua; Collins, Andrew; Gibson, Jane; Tapper, William J; Hunt, Sarah; Deloukas, Panos; Bentley, David R.; Morton, Newton E.

    2004-01-01

    Genetic maps in linkage disequilibrium (LD) units play the same role for association mapping as maps in centimorgans provide at much lower resolution for linkage mapping. Association mapping of genes determining disease susceptibility and other phenotypes is based on the theory of LD, here applied to relations with three phenomena. To test the theory, markers at high density along a 10-Mb continuous segment of chromosome 20q were studied in African-American, Asian, and Caucasian samples. Popu...

  20. The potential for price co-operation in a hydroelectric power market with temporary bottlenecks

    International Nuclear Information System (INIS)

    The report discusses whether there is a larger potential for coordinated price stipulation in a hydropower market that periodically has limitations in the transmission capacity. Such limitations in the transmission capacities transform an integrated market into lesser market segments and this will be reflected in price differences between the segments. The total production in a power market with hydropower producers is dependent on the afflux. Hydropower producers with storage capacities have a large flexibility with respect to power production because the water in a water reservoir may be stored until the production period. Depending on the theoretical model in use the discount factor for coordinated price stipulation will be lower in a hydropower market with periodical limitations in the transmission capacities than in an integrated power market with optimal production adaptation

  1. Feeding behaviour and digestive physiology in larval fish: current knowledge, and gaps and bottlenecks in research

    OpenAIRE

    Rønnestad, Ivar; Yúfera, Manuel; Ueberschär, Bernd; Ribeiro, Laura; Saele, Øystein; Boglione, Clara

    2013-01-01

    Food uptake follows rules defined by feeding behaviour that determines the kind and quantity of food ingested by fish larvae as well as how live prey and food particles are detected, captured and ingested. Feeding success depends on the progressive development of anatomical characteristics and physiological functions and on the availability of suitable food items throughout larval development. The fish larval stages present eco-morpho-physiological features very different from adults and diff...

  2. Strategic behavior and social outcomes in a bottleneck queue: experimental evidence

    DEFF Research Database (Denmark)

    Breinbjerg, Jesper Breinbjerg; Sebald, Alexander Christopher; Østerdal, Lars Peter

    2016-01-01

    first-in-first-out (FIFO), last-in-first-out (LIFO), and service-in-random-order (SIRO) queue disciplines and compare these predictions to outcomes from a laboratory experiment. In line with our theoretical predictions, we find that people arrive with greater dispersion when participating under the LIFO...... discipline, whereas they tend to arrive immediately under FIFO and SIRO. As a consequence, shorter waiting times are obtained under LIFO as compared to FIFO and SIRO. However, while our theoretical predictions admit higher welfare under LIFO, this is not recovered experimentally as the queue disciplines...

  3. Relative quantification in seed GMO analysis: state of art and bottlenecks.

    Science.gov (United States)

    Chaouachi, Maher; Bérard, Aurélie; Saïd, Khaled

    2013-06-01

    Reliable quantitative methods are needed to comply with current EU regulations on the mandatory labeling of genetically modified organisms (GMOs) and GMO-derived food and feed products with a minimum GMO content of 0.9 %. The implementation of EU Commission Recommendation 2004/787/EC on technical guidance for sampling and detection which meant as a helpful tool for the practical implementation of EC Regulation 1830/2003, which states that "the results of quantitative analysis should be expressed as the number of target DNA sequences per target taxon specific sequences calculated in terms of haploid genomes". This has led to an intense debate on the type of calibrator best suitable for GMO quantification. The main question addressed in this review is whether reference materials and calibrators should be matrix based or whether pure DNA analytes should be used for relative quantification in GMO analysis. The state of the art, including the advantages and drawbacks, of using DNA plasmid (compared to genomic DNA reference materials) as calibrators, is widely described. In addition, the influence of the genetic structure of seeds on real-time PCR quantitative results obtained for seed lots is discussed. The specific composition of a seed kernel, the mode of inheritance, and the ploidy level ensure that there is discordance between a GMO % expressed as a haploid genome equivalent and a GMO % based on numbers of seeds. This means that a threshold fixed as a percentage of seeds cannot be used as such for RT-PCR. All critical points that affect the expression of the GMO content in seeds are discussed in this paper. PMID:23400878

  4. Kinetic bottlenecks to chemical exchange rates for deep-sea animals – Part 1: Oxygen

    Directory of Open Access Journals (Sweden)

    E. T. Peltzer

    2012-10-01

    Full Text Available Ocean warming will reduce dissolved oxygen concentrations which can pose challenges to marine life. Oxygen limits are traditionally reported simply as a static concentration thresholds with no temperature, pressure or flow rate dependency. Here we treat the oceanic oxygen supply potential for heterotrophic consumption as a dynamic molecular exchange problem analogous to familiar gas exchange processes at the sea surface. A combination of the purely physico-chemical oceanic properties temperature, hydrostatic pressure, and oxygen concentration defines the ability of the ocean to supply oxygen to any given animal. This general oceanic oxygen supply potential is modulated by animal specific properties such as the diffusive boundary layer thickness to define and limit maximal oxygen supply rates. Here we combine all these properties into formal, mechanistic equations defining novel oceanic properties that subsume various relevant classical oceanographic parameters to better visualize, map, comprehend, and predict the impact of ocean deoxygenation on aerobic life. By explicitly including temperature and hydrostatic pressure into our quantities, various ocean regions ranging from the cold deep-sea to warm, coastal seas can be compared. We define purely physico-chemical quantities to describe the oceanic oxygen supply potential, but also quantities that contain organism-specific properties which in a most generalized way describe general concepts and dependencies. We apply these novel quantities to example oceanic profiles around the world and find that temperature and pressure dependencies of diffusion and partial pressure create zones of greatest physical constriction on oxygen supply typically at around 1000 m depth, which coincides with oxygen concentration minimum zones. In these zones, which comprise the bulk of the world ocean, ocean warming and deoxygenation have a clear negative effect for aerobic life. In some shallow and warm waters the enhanced diffusion and higher partial pressure due to higher temperatures might slightly overcompensate for oxygen concentration decreases due to decreases in solubility.

  5. Why U.S. gasoline costs are bottlenecked: An editorial on oil P.R

    International Nuclear Information System (INIS)

    It is widely acknowledged that massive funds will have to be injected to expand production and supplies of crude oil, natural gas, and derivatives from the Middle East, former Soviet Union, and other producing areas to accommodate future world consumption. In the US, a combination of high business costs and denied access to high potential oil fields are causing the migration of talent and dollars abroad - probably for many years to come. but for the remainder of this decade, there are new strains on the domestic refined-product supply and marketing systems due to a lack of public appreciation of rising environmental-protection costs. This issue presents publisher Thilby Lundberg's address to the Los angeles petroleum Club on Oct. 14, 1992; it is an anecdotal account of US oil industry developments, and their public perceptions, during the period 1950-2000. This issue also presents the following: the ED Refining netback Data Series for the US Gulf and West Coasts, Rotterdam and Singapore as of oct. 9, 1992; and (2) the ED Fuel Price/Tax Series for countries of the Western Hemisphere, October 1992 Edition

  6. Addressing the medicinal chemistry bottleneck: a lean approach to centralized purification.

    Science.gov (United States)

    Weller, Harold N; Nirschl, David S; Paulson, James L; Hoffman, Steven L; Bullock, William H

    2012-09-10

    The use of standardized lean manufacturing principles to improve drug discovery productivity is often thought to be at odds with fostering innovation. This manuscript describes how selective implementation of a lean optimized process, in this case centralized purification for medicinal chemistry, can improve operational productivity and increase scientist time available for innovation. A description of the centralized purification process is provided along with both operational and impact (productivity) metrics, which indicate lower cost, higher output, and presumably more free time for innovation as a result of the process changes described. PMID:22909004

  7. Bottlenecks in the Transferability of Antibiotic Resistance from Natural Ecosystems to Human Bacterial Pathogens

    OpenAIRE

    Martínez, José L.

    2012-01-01

    It is generally accepted that resistance genes acquired by human pathogens through horizontal gene transfer originated in environmental, non-pathogenic bacteria. As a consequence, there is increasing concern on the roles that natural, non-clinical ecosystems, may play in the evolution of resistance. Recent studies have shown that the variability of determinants that can provide antibiotic resistance on their expression in a heterologous host is much larger than what is actually found in human...

  8. Bottlenecks in the transmission of antibiotic resistance from natural ecosystems to human bacterial pathogens

    OpenAIRE

    Martinez, Jose L.

    2012-01-01

    It is generally accepted that resistance genes acquired by human pathogens trough horizontal gene transfer have been originated in environmental, non pathogenic bacteria. As the consequence, there exists an increasing concern on the role that natural, non-clinical ecosystems, may play on the evolution of resistance. Recent studies have shown that the variability of determinants that can provide antibiotic resistance upon their expression in a heterologous host is much larger than what is actu...

  9. Bottlenecks in the transmission of antibiotic resistance from natural ecosystems to human bacterial pathogens

    Directory of Open Access Journals (Sweden)

    Jose L Martinez

    2012-01-01

    Full Text Available It is generally accepted that resistance genes acquired by human pathogens trough horizontal gene transfer have been originated in environmental, non pathogenic bacteria. As the consequence, there exists an increasing concern on the role that natural, non-clinical ecosystems, may play on the evolution of resistance. Recent studies have shown that the variability of determinants that can provide antibiotic resistance upon their expression in a heterologous host is much larger than what is actually found in human pathogens. Along the review, the role that different processes as founder effect, ecological connectivity, fitness costs or second-order selection may have on the establishment of a specific resistance determinant in the population of bacterial pathogens is analysed.

  10. Land, Fund and Mechanism: Three Bottlenecks of Chinese Urban Forestry in the 21st Century

    Institute of Scientific and Technical Information of China (English)

    LIU Deliang; LI jiyue; ZUO Jiafu

    2006-01-01

    Although desirable developments have been achieved since the implementation of the reform-and-opening-up policy, the urban forestry in China is still haunted by the problems of land scarcity, fund shortage and administrative mechanism dysfunction. With a concern of these problems, this paper have made a survey of the current status of the land use in urban areas for the purpose of proposing strategies for urban forestry development in China, and have made an evaluation on the relation between fund and urban forestry with a focus on the means of attracting investment and raising fund. In line with the system of social organizations, of administration, and of management, special concern about the systematic and operational mechanism of urban forestry has been expressed. Based upon the analysis as such, this paper holds that land is the foundation of urban forestry development; fund is the motive force of the sustainable development of urban forestry; mechanism is the guarantee for the urban forestry to develop in a healthy and effective order.

  11. Breaking the bottleneck: high-speed medical image transmission through ATM network--implementation and application

    Science.gov (United States)

    Dai, Hailei L.; Meissner, Marion C.; Cleary, Kevin R.; Rodgers, James E.

    1997-05-01

    In this paper, Georgetown University Medical Center's (GUMC) experience with utilizing ATM technology in a telemedicine application will be presented. This application involves 3D radiation treatment planning where radiological imaging, calculation of the treatment plan, and 3D display all take place at different sites. To do this, GUMC must exchange large amounts of radiology images and data with other institutions in real time. A high speed network consisting of an ATM infrastructure and satellite links was created to connect seamlessly the three sites, GUMC, University of Hawaii, and Ohio Supercomputing Center, which are thousands of miles apart. This paper studies the performance of the ATM network between GUMC and Goddard Space Flight Center, which provides satellite service to link partners in this project. The steps required to test and evaluate the ATM system will be presented. A performance comparison between ATM and Internet-LAN connections will be featured in the presentation. In particular, the theoretical speed of 155 Mbps is hard to reach due to the lack of ATM-native protocols in the transport level of the communication structure.

  12. Bottlenecks in the prediction of regioselectivity of [4 + 2] cycloaddition reactions: An assessment of reactivity descriptors

    Indian Academy of Sciences (India)

    G Gayatri; G Narahari Sastry

    2005-09-01

    B3LYP/6-31G() calculations were performed to obtain all the transition states and products for the 128 distinct reaction channels of Diels-Alder reactions by taking all possible combinations from a series of dienes (1N-a, 1N-b, 2N, 1P-a, 1P-b, 2P, 1O, 1S) and dienophiles (NE, PE, OE, SE, AE, OHE, MeE, CNE). The predictive ability of the values to gauge the regioselectivity of the putative [4 + 2] cycloaddition reactions is analysed. No correlation is obtained between the reaction energies and activation energies. The extent of asynchronicity is measured based on the bond order analysis. DFT-based descriptors such as the local softness ($s^{+}_{k}$ and $s_{k}^{-}$), Fukui function indices ($f^{+}_{k}$ and $f_{k}^{-}$), global electrophilicity index () and local electrophilicity index () were found to be better than the conventional FMO predictions.

  13. Breaking the bottleneck : how best can we bring oil sands products to demanding markets

    International Nuclear Information System (INIS)

    Alberta-based Altex Energy Ltd. is pursuing the development of an innovative heavy oil/bitumen pipeline from Alberta to the United States Gulf Coast (USGC). This energy infrastructure development company is led by a proven management team that developed and constructed the 3,700 km long Alliance Pipeline system. This presentation included a map of the $3.7 billion dollar Alliance Pipeline that identified the mainline compressor stations, lateral compressor stations, area offices and head offices. It was noted that oilsands will represent the most significant resource plays for many years. A graph indicating bitumen supply forecasts from 2005 to 2020 suggests that bitumen production will have exponential growth over the foreseeable future. Labor, materials and infrastructure limitations will create barriers to oilsands growth, as will uncertain market access. For that reason, assured pipeline capacity is needed along with an infrastructure to refineries and a favourable competitive balance for Canadian producers. The presentation addressed issues regarding marketing choices and the challenges of upgrading in Alberta. The economics of diluting heavy oil was also discussed along with industry response to the diluent challenge. Altex's proposed solution of a new direct greenfield pipeline from Alberta to the USGC would reach the largest refinery market in North America as well as the largest heavy oil/bitumen consuming regions. The Altex solution would be complementary to heavy oil/bitumen in Alberta. The proprietary pipeline technology permits alternative diluents, eliminating much of the diluent penalty. It mitigates the risks of upgrading in Alberta and competes on a cost basis with other expansion alternatives. The Altex pipeline system eliminates the need for costly condensate diluent, but accepts all current diluents. It transports up to 90 per cent more bitumen than clean diluted bitumen in a conventional pipeline. It can also transport as much as 175 per cent more bitumen than a synthetic bitumen blend in a conventional pipeline. The capital cost of the Altex pipeline is comparable to a conventional pipeline. tabs., figs

  14. Kinetic bottlenecks to chemical exchange rates for deep-sea animals II: Carbon dioxide

    OpenAIRE

    Hofmann, Andreas F.; Peltzer, Edward T.; Brewer, Peter G.

    2012-01-01

    Increased ocean acidification from fossil fuel CO2 invasion, from temperature-driven changes in respiration, and from possible leakage from sub-seabed geologic CO2 disposal has aroused concern over the impacts of elevated CO2 concentrations on marine life. 5 Discussion of these impacts has so far focused only on changes in the oceanic bulk fluid properties as the critical variable and with a major focus on carbonate shell dissolution. Here we describe the rate problem for anima...

  15. Kinetic bottlenecks to chemical exchange rates for deep-sea animals - Part 2: Carbon Dioxide

    OpenAIRE

    Hofmann, Andreas F.; Peltzer, Edward T.; Brewer, Peter G.

    2013-01-01

    Increased ocean acidification from fossil fuel CO2 invasion, from temperature-driven changes in respiration, and from possible leakage from sub-seabed geologic CO2 disposal has aroused concern over the impacts of elevated CO2 concentrations on marine life. Discussion of these impacts has so far focused only on changes in the oceanic bulk fluid properties (Delta pH, Delta [Sum CO2], etc.) as the critical variable and with a major focus on carbonate shell formation. Here we describe...

  16. End-Devonian extinction and a bottleneck in the early evolution of modern jawed vertebrates

    OpenAIRE

    Sallan, Lauren Cole; Coates, Michael I.

    2010-01-01

    The Devonian marks a critical stage in the early evolution of vertebrates: It opens with an unprecedented diversity of fishes and closes with the earliest evidence of limbed tetrapods. However, the latter part of the Devonian has also been characterized as a period of global biotic crisis marked by two large extinction pulses: a “Big Five” mass extinction event at the Frasnian-Famennian stage boundary (374 Ma) and the less well-documented Hangenberg event some 15 million years later at the De...

  17. Variable temporo-insular cortex neuroanatomy in primates suggests a bottleneck effect in eastern gorillas

    OpenAIRE

    Barks, Sarah K.; Bauernfeind, Amy L.; Bonar, Christopher J.; Cranfield, Michael R.; de Sousa, Alexandra A.; Erwin, Joseph M.; Hopkins, William D.; Lewandowski, Albert H.; Mudakikwa, Antoine; Phillips, Kimberley A.; Raghanti, Mary Ann; Stimpson, Cheryl D.; Hof, Patrick R; Zilles, Karl; Sherwood, Chet C.

    2014-01-01

    In this study, we describe an atypical neuroanatomical feature present in several primate species that involves a fusion between the temporal lobe (often including Heschl’s gyrus in great apes) and the posterior dorsal insula, such that a portion of insular cortex forms an isolated pocket medial to the Sylvian fissure. We assessed the frequency of this fusion in 56 primate species (including apes, Old World monkeys, New World monkeys, and strepsirrhines) using either magnetic resonance images...

  18. Advances and bottlenecks in modelling the greenhouse climate: summary of a group discussion

    OpenAIRE

    Seginer, I.; Bakker, J.C.

    1998-01-01

    This report is a summary of a group discussion at the symposium 'Models in protected cultivation' held in Wageningen, August 1997. The discussion focused on the reasons for the relatively limited acceptance and application of greenhouse climate models, especially in commercial practice. The discussion focused on the reasons for the relatively limited acceptance and application of greenhouse climate models, especially in commercial practice. Three application types were mentioned: Education (a...

  19. Meta-Analysis of mitochondrial DNA reveals several population bottlenecks during worldwide migrations of cattle

    NARCIS (Netherlands)

    Lenstra, Johannes A.; Ajmone-Marsan, Paolo; Beja-Pereira, Albano; Bollongino, Ruth; Bradley, Daniel G.; Colli, Licia; De Gaetano, Anna; Edwards, Ceiridwen J.; Felius, Marleen; Ferretti, Luca; Ginja, Catarina; Hristov, Peter; Kantanen, Juha; Lirón, Juan Pedro; Magee, David A.; Negrini, Riccardo; Radoslavov, Georgi A.

    2014-01-01

    Several studies have investigated the differentiation of mitochondrial DNA in Eurasian, African and American cattle as well as archaeological bovine material. A global survey of these studies shows that haplogroup distributions are more stable in time than in space. All major migrations of cattle ha

  20. A recent bottleneck of Y chromosome diversity coincides with a global change in culture

    DEFF Research Database (Denmark)

    Karmin, Monika; Saag, Lauri; Vicente, Mário;

    2015-01-01

    ancient DNA calibration, we date the Y-chromosomal most recent common ancestor (MRCA) in Africa at 254 (95% CI 192-307) kya and detect a cluster of major non-African founder haplogroups in a narrow time interval at 47-52 kya, consistent with a rapid initial colonization model of Eurasia and Oceania after...

  1. Multitasking or Continuous Partial Attention: A Critical Bottleneck for Digital Natives

    Science.gov (United States)

    Firat, Mehmet

    2013-01-01

    With the beginning of the second half of the past century, advances in Information and Communication Technologies had unprecedented influence deeply felt in all social structures. The effects were so much widespread that the differences in technology use have created a huge gap between generations in terms of everyday life and lifestyle. As a…

  2. No severe bottleneck during human evolution: evidence from two apolipoprotein C-II deficiency alleles.

    OpenAIRE

    Xiong, W J; Li, W. H.; Posner, I; Yamamura, T.; Yamamoto, A.; Gotto, A M; Chan, L

    1991-01-01

    The DNA sequences of a Japanese and a Venezuelan apolipoprotein (apo) C-II deficiency allele, of a normal Japanese apo C-II gene, and of a chimpanzee apo C-II gene were amplified by PCR, and their nucleotide sequences were determined on multiple clones of the PCR products. The normal Japanese sequence is identical to--and the chimpanzee sequence differs by only three nucleotides from--a previously published normal Caucasian sequence. In contrast, the two human mutant sequences each differ fro...

  3. Bottleneck of using single memristor as a synapse and its solution

    CERN Document Server

    Merrikh-Bayat, Farnood

    2010-01-01

    Physical realization of the first memristor by researchers at Hewlett Packard (HP) labs attracts so much interest in this newly found circuit element which has so many applications specially in a field of neuromorphic systems. Now, it is well known that one of the main applications of memristor is for the hardware implementation of synapses because of their capability in dense fabrication and acting as a perfect analog memory. However, synapses in biological systems have this property that by progressing in the learning process, variation rate of the synapses weights should decrease which is not the case in the currently suggested memristor-based structures of neuromorphic systems. In this paper, we show that using two dissimilar memristors connected in series as a synapse perform better than the single memristor.

  4. Renewable marine energies, state of the art, technological bottlenecks and perspectives

    International Nuclear Information System (INIS)

    The ocean is a huge reservoir of energy that is very little worked. This article reviews the different ways to use the energy stored in the ocean: -) thermal energy, -) the energy of the ocean streams, -) the energy of the tides, -) the energy of the waves, and -) the off-coast wind energy. This article reviews the different projects throughout the world, the potentialities of such energies and the technical challenges to overcome. (A.C.)

  5. Examinations and Educational Opportunity in China: Mobility and Bottlenecks for the Rural Poor

    Science.gov (United States)

    Hannum, Emily; An, Xuehui; Cherng, Hua-Yu Sebastian

    2011-01-01

    Despite the important role played by examinations in educational stratification and mobility in China, to our knowledge there is no literature in English that investigates the impact of exams on educational attainment with empirical data. We address this gap with an investigation of how examinations shape opportunities for children of the rural…

  6. Overcoming the matched-sample bottleneck: an orthogonal approach to integrate omic data.

    Science.gov (United States)

    Nguyen, Tin; Diaz, Diana; Tagett, Rebecca; Draghici, Sorin

    2016-01-01

    MicroRNAs (miRNAs) are small non-coding RNA molecules whose primary function is to regulate the expression of gene products via hybridization to mRNA transcripts, resulting in suppression of translation or mRNA degradation. Although miRNAs have been implicated in complex diseases, including cancer, their impact on distinct biological pathways and phenotypes is largely unknown. Current integration approaches require sample-matched miRNA/mRNA datasets, resulting in limited applicability in practice. Since these approaches cannot integrate heterogeneous information available across independent experiments, they neither account for bias inherent in individual studies, nor do they benefit from increased sample size. Here we present a novel framework able to integrate miRNA and mRNA data (vertical data integration) available in independent studies (horizontal meta-analysis) allowing for a comprehensive analysis of the given phenotypes. To demonstrate the utility of our method, we conducted a meta-analysis of pancreatic and colorectal cancer, using 1,471 samples from 15 mRNA and 14 miRNA expression datasets. Our two-dimensional data integration approach greatly increases the power of statistical analysis and correctly identifies pathways known to be implicated in the phenotypes. The proposed framework is sufficiently general to integrate other types of data obtained from high-throughput assays. PMID:27403564

  7. Analysing I/O bottlenecks in LHC data analysis on grid storage resources

    CERN Document Server

    CERN. Geneva

    2012-01-01

    We describe recent I/O testing frameworks that we have developed and applied within the UK GridPP Collaboration, the ATLAS experiment and the DPM team, for a variety of distinct purposes. These include benchmarking vendor supplied storage products, discovering scaling limits of SRM solutions, tuning of storage systems for experiment data analysis, evaluating file access protocols, and exploring IO read patterns of experiment software and their underlying event data models. With multiple grid sites now dealing with petabytes of data, such studies are becoming increasingly essential. We describe how the tests build, and improve, on previous work and contrast how the use-cases differ. We also detail the results obtained and the implications for storage hardware, middleware and experiment software.

  8. Kinetic bottlenecks to chemical exchange rates for deep-sea animals II: Carbon dioxide

    Directory of Open Access Journals (Sweden)

    A. F. Hofmann

    2012-11-01

    Full Text Available Increased ocean acidification from fossil fuel CO2 invasion, from temperature-driven changes in respiration, and from possible leakage from sub-seabed geologic CO2 disposal has aroused concern over the impacts of elevated CO2 concentrations on marine life. Discussion of these impacts has so far focused only on changes in the oceanic bulk fluid properties (ΔpH, Δ[∑CO2] etc. as the critical variable and with a major focus on carbonate shell dissolution. Here we describe the rate problem for animals that must export CO2 at about the same rate at which O2 is consumed. We analyze the basic properties controlling CO2 export within the diffusive boundary layer around marine animals in an ocean changing in temperature (T and CO2 concentration in order to compare the challenges posed by O2 uptake under stress with the equivalent problem of CO2 expulsion. The problem is more complex than that for a non-reactive gas since, as with gas exchange of CO2 at the air-sea interface, the influence of the ensemble of reactions within the CO2-HCO3-CO32– acid-base system needs to be considered. These reactions significantly facilitate CO2 efflux compared to O2 intake at equal temperature, pressure and flow rate under typical oceanic concentrations.The effect of these reactions can be described by an enhancement factor. For organisms, this means mechanically increasing flow over their surface to thin the boundary layer as is required to alleviate O2 stress seems not necessary to facilitate CO2 efflux. Nevertheless the elevated pCO2 cost most likely is non-zero. Regionally as with O2 the combination of T, P, and pH/pCO2 creates a zone of maximum CO2 stress at around 1000 m depth. But the net result is that, for the problem of gas exchange with the bulk ocean, the combination of an increasing T combined with declining O2 poses a greater challenge to marine life than does increasing CO2. The relationships developed here allow a more accurate prediction of the impacts on marine life from the combined effects of changing T, O2, and CO2 than can be estimated from single variable studies.

  9. Kinetic bottlenecks to chemical exchange rates for deep-sea animals – Part 2: Carbon Dioxide

    Directory of Open Access Journals (Sweden)

    A. F. Hofmann

    2013-04-01

    Full Text Available Increased ocean acidification from fossil fuel CO2 invasion, from temperature-driven changes in respiration, and from possible leakage from sub-seabed geologic CO2 disposal has aroused concern over the impacts of elevated CO2 concentrations on marine life. Discussion of these impacts has so far focused only on changes in the oceanic bulk fluid properties (ΔpH, Δ[∑ CO2], etc. as the critical variable and with a major focus on carbonate shell formation. Here we describe the rate problem for animals that must export CO2 at about the same rate at which O2 is consumed. We analyse the basic properties controlling CO2 export within the diffusive boundary layer around marine animals in an ocean changing in temperature (T and CO2 concentration in order to compare the challenges posed by O2 uptake under stress with the equivalent problem of CO2 expulsion. The problem is more complex than that for a non-reactive gas, since with CO2 the influence of the seawater carbonate acid-base system needs to be considered. These reactions significantly facilitate CO2 efflux compared to O2 intake at equal temperature, pressure and fluid flow rate under typical oceanic concentrations. The effect of these reactions can be described by an enhancement factor, similar to that widely used for CO2 invasion at the sea surface. While organisms do need to actively regulate flow over their surface to thin the boundary layer to take up enough O2, this seems to be not necessary to facilitate CO2 efflux. Instead, the main impacts of rising oceanic CO2 will most likely be those associated with classical ocean acidification science. Regionally, as with O2, the combination of T, P and pH/pCO2 creates a zone of maximum CO2 stress at around 1000 m depth.

  10. Enforcing the right to food in India: Bottlenecks in delivering the expected outcome

    OpenAIRE

    Cheriyan, George

    2006-01-01

    Over the past decade, a series of events in India have brought the question of food security into sharp focus. Vast famine-affected areas versus surplus production and stocks of grains, the impact of globalization and World Trade Organization laws on agriculture and farmers, the media’s spotlight on starvation deaths and, finally, the Supreme Court of India’s strong reaction to the plight of the hungry—all make a case for recognizing the right to food. This paper examines the situation prevai...

  11. MULTITASKING OR CONTINUOUS PARTIAL ATTENTION: A CRITICAL BOTTLENECK FOR DIGITAL NATIVES

    Directory of Open Access Journals (Sweden)

    Mehmet FIRAT

    2013-01-01

    Full Text Available With the beginning of the second half of the past century, advances in Information and Communication Technologies had unprecedented influence deeply felt in all social structures. The effects were so much widespread that the differences in technology use have created a huge gap between generations in terms of everyday life and lifestyle. As a result, two groups occurred; those growing with technology digital natives and digital immigrants who try to keep pace with technology. Today, the computer, internet and mobile technologies like e-book readers, mobile phones, android devices, smart phones and tablet computers have become all-day business and communication tools used by digital natives. However, these high-tech tools, with their speed and ease of use, revealed some important issues that deeply affect digital natives' way of life. Among these most important effects are Continuous Partial Attention and Multitasking. In this study, these two conditions faced by digital natives were compared, and some suggestions have been put forward for the digital native learners.

  12. Photosynthesis driven crop growth models for greenhouse cultivation; advances and bottlenecks.

    OpenAIRE

    Challa, H.; Heuvelink, E.

    1996-01-01

    In recent years considerable progress has been made in modelling growth of green-house crops. Nevertheless, the share of research in this field compared to crop modelling in general is only a few percent. Yet, crop growth models have a great potential for greenhouse production systems, because they are characterised by a high degree of complexity, intensity and diversity. Therefore it is important that crop growth models find a wider application in research and in practice. To achieve a wider...

  13. Surviving in Changing Seascapes: Sediment Dynamics as Bottleneck for Long-Term Seagrass Presence

    NARCIS (Netherlands)

    Suykerbuyk, W.; Bouma, T.J.; Govers, L.L.; Giesen, K.; de Jong, D.J.; Herman, P.M.J.; Hendriks, J.; van Katwijk, M.M.

    2016-01-01

    Changes in the seascape often result in altered hydrodynamics that lead to coinciding changes in sediment dynamics. Little is known on how altered sediment dynamics affect long-term seagrass persistence. We studied the thresholds of sediment dynamics in relation to seagrass presence by comparing sed

  14. Surviving in changing seascapes : Sediment dynamics as bottleneck for long-term seagrass presence

    NARCIS (Netherlands)

    Suykerbuyk, Wouter; Bouma, Tjeerd J.; Govers, Laura L.; Giesen, Kris; de Jong, Dick J.; Herman, Peter; Hendriks, Jan; van Katwijk, Marieke M.

    2016-01-01

    Changes in the seascape often result in altered hydrodynamics that lead to coinciding changes in sediment dynamics. Little is known on how altered sediment dynamics affect long-term seagrass persistence. We studied the thresholds of sediment dynamics in relation to seagrass presence by comparing sed

  15. Surviving in Changing Seascapes: Sediment Dynamics as Bottleneck for Long-Term Seagrass Presence

    OpenAIRE

    Suykerbuyk, W.; Bouma, T.J.; Govers, L.L.; Giesen, K.; de Jong, D J; Herman, P.M.J.; Hendriks, J.; van Katwijk, M. M.

    2016-01-01

    Changes in the seascape often result in altered hydrodynamics that lead to coinciding changes in sediment dynamics. Little is known on how altered sediment dynamics affect long-term seagrass persistence. We studied the thresholds of sediment dynamics in relation to seagrass presence by comparing sediment characteristics and seagrass presence data of seven separate seagrass meadows. All meadows had a long-term (>20 years) presence. Within these meadows, we distinguish so-called “hotspots” (are...

  16. A systems biology approach for the characterization of metabolic bottlenecks in recombinant protein production processes

    OpenAIRE

    Carneiro, S.

    2010-01-01

    O trabalho realizado no âmbito desta tese teve como principal finalidade a avaliação das alterações metabólicas relacionadas com a produção de proteínas recombinantes em células bacterianas de Escherichia coli e a consequente activação de respostas de stress. Foi evidenciada a resposta restringente promovida pela actividade da enzima RelA, dado ser uma das principais respostas de stress induzidas pelo decréscimo da quantidade de aminoácidos disponíveis no meio intracelular como...

  17. Population Bottlenecks during the Infectious Cycle of the Lyme Disease Spirochete Borrelia burgdorferi

    Czech Academy of Sciences Publication Activity Database

    Rego, Ryan O. M.; Bestor, A.; Štefka, Jan; Rosa, P. A.

    2014-01-01

    Roč. 9, č. 6 (2014), e101009. E-ISSN 1932-6203 Institutional support: RVO:60077344 Keywords : sensu stricto * mammalian host * peromyscus-leucopus * Ixodes ricinus * ticks * mice * transmission * dissemination * diversity * North America Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 3.234, year: 2014

  18. Flow and clogging of a sheep herd passing through a bottleneck

    Science.gov (United States)

    Garcimartín, A.; Pastor, J. M.; Ferrer, L. M.; Ramos, J. J.; Martín-Gómez, C.; Zuriguel, I.

    2015-02-01

    We present an experimental study of a flock passing through a narrow door. Video monitoring of daily routines in a farm has enabled us to collect a sizable amount of data. By measuring the time lapse between the passage of consecutive animals, some features of the flow regime can be assessed. A quantitative definition of clogging is demonstrated based on the passage time statistics. These display broad tails, which can be fitted by power laws with a relatively large exponent. On the other hand, the distribution of burst sizes robustly evidences exponential behavior. Finally, borrowing concepts from granular physics and statistical mechanics, we evaluate the effect of increasing the door size and the performance of an obstacle placed in front of it. The success of these techniques opens new possibilities regarding their eventual extension to the management of human crowds.

  19. Development of arbuscular mycorrhizal biotechnology and industry: current achievements and bottlenecks

    Czech Academy of Sciences Publication Activity Database

    Vosátka, Miroslav; Látr, A.; Gianinazzi, S.; Albrechtová, Jana

    2013-01-01

    Roč. 58, 1-3 (2013), s. 29-37. ISSN 0334-5114 R&D Projects: GA MPO FR-TI1/299 Institutional research plan: CEZ:AV0Z60050516 Institutional support: RVO:67985939 Keywords : arbuscular mycorrhizal fungi * sustainable agriculture * inoculum quality Subject RIV: EF - Botanics Impact factor: 0.941, year: 2013

  20. Dynamic bottleneck optimization for k-edge and 2-vertex connectivity

    DEFF Research Database (Denmark)

    Telelis, Orestis; Zissimopoulos, Vassilis

    2008-01-01

    We consider the problem of updating efficiently the minimum value b over a weighted graph, so that edges with a cost less than b induce a spanning subgraph satisfying a k-edge or 2-vertex connectivity constraint, when the cost of an edge of the graph is updated. Our results include update algorit...... algorithms of almost linear time (up to poly-logarithmic factors) in the number of vertices for all considered connectivity constraints (for fixed k), and a worst case construction showing that these algorithms are almost optimal in their class....

  1. Processes for non-destructive transfer of graphene: widening the bottleneck for industrial scale production

    Science.gov (United States)

    Zaretski, Aliaksandr V.; Lipomi, Darren J.

    2015-05-01

    The exceptional charge-transport, mechanical, and barrier properties of graphene are well known. High-quality films of single-layer graphene produced over large areas, however, are extremely expensive. The high cost of graphene precludes its use in industries--such as transparent electrodes and flexible packaging--that might take full advantage of its properties. This minireview presents several strategies for the transfer of graphene from the substrates used for growth to substrates used for the final application. Each strategy shares the characteristic of being non-destructive: that is, the growth substrate remains reusable for further synthesis of new graphene. These processes have the potential to lower significantly the costs of manufacturing graphene, to increase production yields, and to minimize environmental impact. This article is divided into sections on (i) the synthesis of high-quality single-layer graphene and (ii) its non-destructive transfer to a host substrate. Section (ii) is further divided according to the substrate from which graphene is transferred: single-crystalline wafers or flexible copper foils. We also comment, wherever possible, on defects produced as a result of the transfer, and potential strategies to mitigate these defects. We conclude that several methods for the green synthesis and transfer of graphene have several of the right characteristics to be useful in industrial scale production.

  2. Meta-Analysis of Mitochondrial DNA Reveals Several Population Bottlenecks during Worldwide Migrations of Cattle

    Directory of Open Access Journals (Sweden)

    Johannes A. Lenstra

    2014-03-01

    Full Text Available Several studies have investigated the differentiation of mitochondrial DNA in Eurasian, African and American cattle as well as archaeological bovine material. A global survey of these studies shows that haplogroup distributions are more stable in time than in space. All major migrations of cattle have shifted the haplogroup distributions considerably with a reduction of the number of haplogroups and/or an expansion of haplotypes that are rare or absent in the ancestral populations. The most extreme case is the almost exclusive colonization of Africa by the T1 haplogroup, which is rare in Southwest Asian cattle. In contrast, ancient samples invariably show continuity with present-day cattle from the same location. These findings indicate strong maternal founder effects followed by limited maternal gene flow when new territories are colonized. However, effects of adaptation to new environments may also play a role.

  3. Population Aging and Migrant Workers: Bottlenecks in Tuberculosis Control in Rural China

    OpenAIRE

    Bele, Sumedh; Jiang, Wei; Lu, Hui; You, Hua; Fan, Hong; Huang, Lifang; Wang, Qungang; Shen, Hongbing; Wang, Jianming

    2014-01-01

    Background Tuberculosis is a serious global health problem. Its paradigms are shifting through time, especially in rapidly developing countries such as China. Health providers in China are at the forefront of the battle against tuberculosis; however, there are few empirical studies on health providers' perspectives on the challenges they face in tuberculosis control at the county level in China. This study was conducted among health providers to explore their experiences with tuberculosis con...

  4. Bottlenecks, population differentiation and apparent selection at microsatellite loci in Australian Drosophila buzzatii

    DEFF Research Database (Denmark)

    Barker, J.S.F.; Frydenberg, Jane; González, J.; Davies, H.I.; Ruiz, A; Sørensen, Jesper Givskov; Loeschcke, Volker

    2009-01-01

    original population simply due to genetic drift. Disentangling the effects of founder drift and selection after colonization is crucial to understanding the adaptive process. Drosophila buzzatii colonized Australia some 600-700 generations ago, and spread rapidly over a wide geographical range. Genetic......Species colonizing new areas disjunct from their original habitat may be subject to novel selection pressures, and exhibit adaptive genetic changes. However, if colonization occurs through a small number of founders, the genetic composition of the colonized population may differ from that of the...

  5. Identifying bottlenecks in charging infrastructure of plug-in hybrid electric vehicles through agent-based traffic simulation

    OpenAIRE

    Lindgren, Juuso; Lund, Peter D.

    2015-01-01

    The effect of different charging infrastructure configurations on the electric-driven distance of plug-in hybrid electric vehicles (e-mileage) has been investigated, using an agent-based traffic simulation. Our findings suggest that the same e-mileage can be achieved with fewer charging poles if the poles support charging from several parking slots around them, and the charging cable is switched from one vehicle to the next. We also find that the charging power supported by most Finnish charg...

  6. Insertional Mutagenesis and Deep Profiling Reveals Gene Hierarchies and a Myc/p53-Dependent Bottleneck in Lymphomagenesis

    NARCIS (Netherlands)

    Huser, C.A.; Gilroy, K.L.; De Ridder, J.; Kilbey, A.; Borland, G.; Mackay, N.; Jenkins, A.; Bell, M.; Herzyk, P.; Van der Weyden, L.; et al.

    2014-01-01

    Retroviral insertional mutagenesis (RIM) is a powerful tool for cancer genomics that was combined in this study with deep sequencing (RIM/DS) to facilitate a comprehensive analysis of lymphoma progression. Transgenic mice expressing two potent collaborating oncogenes in the germ line (CD2-MYC, -Runx

  7. Insertional mutagenesis and deep profiling reveals gene hierarchies and a Myc/p53-dependent bottleneck in lymphomagenesis.

    Science.gov (United States)

    Huser, Camille A; Gilroy, Kathryn L; de Ridder, Jeroen; Kilbey, Anna; Borland, Gillian; Mackay, Nancy; Jenkins, Alma; Bell, Margaret; Herzyk, Pawel; van der Weyden, Louise; Adams, David J; Rust, Alistair G; Cameron, Ewan; Neil, James C

    2014-02-01

    Retroviral insertional mutagenesis (RIM) is a powerful tool for cancer genomics that was combined in this study with deep sequencing (RIM/DS) to facilitate a comprehensive analysis of lymphoma progression. Transgenic mice expressing two potent collaborating oncogenes in the germ line (CD2-MYC, -Runx2) develop rapid onset tumours that can be accelerated and rendered polyclonal by neonatal Moloney murine leukaemia virus (MoMLV) infection. RIM/DS analysis of 28 polyclonal lymphomas identified 771 common insertion sites (CISs) defining a 'progression network' that encompassed a remarkably large fraction of known MoMLV target genes, with further strong indications of oncogenic selection above the background of MoMLV integration preference. Progression driven by RIM was characterised as a Darwinian process of clonal competition engaging proliferation control networks downstream of cytokine and T-cell receptor signalling. Enhancer mode activation accounted for the most efficiently selected CIS target genes, including Ccr7 as the most prominent of a set of chemokine receptors driving paracrine growth stimulation and lymphoma dissemination. Another large target gene subset including candidate tumour suppressors was disrupted by intragenic insertions. A second RIM/DS screen comparing lymphomas of wild-type and parental transgenics showed that CD2-MYC tumours are virtually dependent on activation of Runx family genes in strong preference to other potent Myc collaborating genes (Gfi1, Notch1). Ikzf1 was identified as a novel collaborating gene for Runx2 and illustrated the interface between integration preference and oncogenic selection. Lymphoma target genes for MoMLV can be classified into (a) a small set of master regulators that confer self-renewal; overcoming p53 and other failsafe pathways and (b) a large group of progression genes that control autonomous proliferation in transformed cells. These findings provide insights into retroviral biology, human cancer genetics and the safety of vector-mediated gene therapy. PMID:24586197

  8. Insertional mutagenesis and deep profiling reveals gene hierarchies and a Myc/p53-dependent bottleneck in lymphomagenesis.

    Directory of Open Access Journals (Sweden)

    Camille A Huser

    2014-02-01

    Full Text Available Retroviral insertional mutagenesis (RIM is a powerful tool for cancer genomics that was combined in this study with deep sequencing (RIM/DS to facilitate a comprehensive analysis of lymphoma progression. Transgenic mice expressing two potent collaborating oncogenes in the germ line (CD2-MYC, -Runx2 develop rapid onset tumours that can be accelerated and rendered polyclonal by neonatal Moloney murine leukaemia virus (MoMLV infection. RIM/DS analysis of 28 polyclonal lymphomas identified 771 common insertion sites (CISs defining a 'progression network' that encompassed a remarkably large fraction of known MoMLV target genes, with further strong indications of oncogenic selection above the background of MoMLV integration preference. Progression driven by RIM was characterised as a Darwinian process of clonal competition engaging proliferation control networks downstream of cytokine and T-cell receptor signalling. Enhancer mode activation accounted for the most efficiently selected CIS target genes, including Ccr7 as the most prominent of a set of chemokine receptors driving paracrine growth stimulation and lymphoma dissemination. Another large target gene subset including candidate tumour suppressors was disrupted by intragenic insertions. A second RIM/DS screen comparing lymphomas of wild-type and parental transgenics showed that CD2-MYC tumours are virtually dependent on activation of Runx family genes in strong preference to other potent Myc collaborating genes (Gfi1, Notch1. Ikzf1 was identified as a novel collaborating gene for Runx2 and illustrated the interface between integration preference and oncogenic selection. Lymphoma target genes for MoMLV can be classified into (a a small set of master regulators that confer self-renewal; overcoming p53 and other failsafe pathways and (b a large group of progression genes that control autonomous proliferation in transformed cells. These findings provide insights into retroviral biology, human cancer genetics and the safety of vector-mediated gene therapy.

  9. Process-induced Distortions in CFRP Manufacturing: A bottle-neck for high-rate Production Scenarios

    OpenAIRE

    Kappel, Erik; Stefaniak, Daniel; Hühne, Christian

    2014-01-01

    Undesired process-induced distortions (PID) are an inherent issue in today's CFRP manufacturing scenarios. Distortions are inevitable due to an interaction of composite-specific and process-specific parameters. In academia it is distinguished in three main phenomena Spring-in, Warpage and Forced- interaction while their specific relevance depends on the part shape at hand. As process distortions remain widely unconsidered in current partdevelopment chains, they induce considera...

  10. Why do organizations not learn from incidents? Bottlenecks, causes and conditions for a failure to effectively learn

    NARCIS (Netherlands)

    Drupsteen, L.; Hasle, P.

    2014-01-01

    If organizations would be able to learn more effectively from incidents that occurred in the past, future incidents and consequential injury or damage can be prevented. To improve learning from incidents, this study aimed to identify limiting factors, i.e. the causes of the failure to effectively le

  11. Identifying bottlenecks in transient and stable production of recombinant monoclonal-antibody sequence variants in Chinese hamster ovary cells

    OpenAIRE

    Mason, Megan; Sweeney, Bernadette; Cain, Katharine; Stephens, Paul; Sharfstein, Susan T.

    2012-01-01

    The increasing demand for antibody-based therapeutics has emphasized the need for technologies to improve recombinant antibody titers from mammalian cell lines. Moreover, as antibody therapeutics address an increasing spectrum of indications, interest has increased in antibody engineering to improve affinity and biological activity. However, the cellular mechanisms that dictate expression and the relationships between antibody sequence and expression level remain poorly understood. Fundamenta...

  12. Why do organizations not learn from incidents? Bottlenecks, causes and conditions for a failure to effectively learn

    DEFF Research Database (Denmark)

    Drupsteen, Linda; Hasle, Peter

    2014-01-01

    If organizations would be able to learn more effectively from incidents that occurred in the past, futureincidents and consequential injury or damage can be prevented. To improve learning from incidents,this study aimed to identify limiting factors, i.e. the causes of the failure to effectively...... learn. In sevenorganizations focus groups were held to discuss factors that according to employees contributed to thefailure to learn. By use of a model of the learning from incidents process, the steps, where difficulties forlearning arose, became visible, and the causes for these difficulties could be...

  13. 民营企业成长中的三大瓶颈%The Three Bottlenecks for Private Enterprises' Development

    Institute of Scientific and Technical Information of China (English)

    周鹏; 任俊正

    2009-01-01

    民营企业成长过程中会受到嵌入反应所形成的市场瓶颈、非契合管理所形成的成本瓶颈以及忽视法人治理建设所形成的治理瓶颈三大瓶颈的制约.民营企业突破三大瓶颈关键在于把握创业激情与战略理性之间的平衡、经验管理与制度管理之间的平衡、治理机制与企业发展之间的平衡.

  14. Bottlenecks and needs in human-human and human-machine interaction - a view from and into the neurosurgical OR.

    Science.gov (United States)

    Blaar, Melanie; Janß, Armin; Dell'Anna, Jasmin; Höllig, Anke; Radermacher, Klaus; Clusmann, Hans

    2016-04-01

    The number and complexity of user interfaces in the OR has been considerably increasing during the last years. Moreover, increasing cost and time pressure force surgeons and surgical nurses to perform different tasks in parallel. We analyzed the workflow of 25 neurosurgical procedures with a workflow analysis tool in order to analyze the present situation in the neurosurgical OR and to identify potential use-oriented risks and to develop first proposals for respective countermeasures. Application of the navigation system, the CUSA ultrasonic aspirator, and the PACS-PC was associated with errors and resulting potential risks. A number of different disruptive factors have been identified, the most prominent of those being intraoperative duty phone calls, longer absence of the circulating nurses or slipped off foot switches. Furthermore, the identified problems may lead to risks for patient, and also for staff by use errors, associated with an inappropriate cognitive workload of the surgeon or nurses. Organizational and technical countermeasures are necessary: to enhance communication, team trainings could be helpful, and the setup of a mailbox could reduce the number of intraoperative duty phone calls. Technical deficiencies have to be reduced, e.g. with more user-oriented design of devices, such as foot switches, or standard design for user interfaces. For further risk reduction in the case of use deficiencies, we propose the implementation of device interoperability and the use of a sterile integrated user interface in a networked OR. PMID:26389631

  15. Coupled-Cluster Theory Employing Approximate Integrals: An Approach to Avoid the Input/Output and Storage Bottlenecks

    Science.gov (United States)

    Rendell, Alistair P.; Lee, Timothy J.

    1994-01-01

    By representing orbital products in an expansion basis, certain classes of two-electron integrals are approximated for use in CCSD(T) calculations (singles and doubles coupled-cluster plus a perturbational estimate of the effects of connected triple excitations). This leads to a very large reduction in disk storage and input/output requirements, with usually only a modest increase in computational effort. The new procedure will allow very large CCSD(T) calculations to be undertaken, limited only by available processor time. Using the molecular basis as the expansion basis, explicit numerical comparisons of equilibrium geometries, harmonic frequencies, and energy differences indicate that the error due to the use of approximate integrals is less than the error associated with truncation of the molecular basis set.

  16. Travelling on a budget : predictions and ecological evidence for bottlenecks in the annual cycle of long-distance migrants

    NARCIS (Netherlands)

    Buehler, Deborah M.; Piersma, Theunis

    2008-01-01

    Long-distance migration, and the study of the migrants who undertake these journeys, has fascinated generations of biologists. However, many aspects of the annual cycles of these migrants remain a mystery as do many of the driving forces behind the evolution and maintenance of the migrations themsel

  17. From the knowledge acquisition bottleneck to the knowledge acquisition overflow: A brief French history of knowledge acquisition

    OpenAIRE

    Aussenac-Gilles, Nathalie; Gandon, Fabien

    2013-01-01

    International audience This article is an account of the evolution of the French-speaking research community on knowledge acquisition and knowledge modelling echoing the complex and cross-disciplinary trajectory of the field. In particular, it reports the most significant steps in the parallel evolution of the web and the knowledge acquisition paradigm, which finally converged with the project of a semantic web. As a consequence of the huge amount of available data in the web, a paradigm s...

  18. Long orbital period pre-polars containing an early K-type donor stars. Bottleneck accretion mechanism in action

    CERN Document Server

    Tovmassian, G; Zharikov, S; Reichart, D E; Haislip, J B; Ivarsen, K M; LaCluyze, A P; Moore, J P; Miroshnichenko, A S

    2016-01-01

    We studied two objects identified as a Cataclysmic Variables (CVs) with periods exceeding the natural boundary for Roche lobe filling ZAMS secondary stars. We present observational results for V1082 Sgr with 20.82 h orbital period, an object that shows low luminosity state, when its flux is totally dominated by a chromospherically active K- star with no signs of ongoing accretion. Frequent accretion shut-offs, together with characteristics of emission lines in a high state, indicate that this binary system is probably detached and the accretion of matter on the magnetic white dwarf takes place through stellar wind from the active donor star via coupled magnetic fields. Its observational characteristics are surprisingly similar to V479 And, a 14.5 h binary system. They both have early K-type stars as a donor star. We argue, that similar to the shorter period pre-polars containing M-dwarfs, these are detached binaries with strong magnetic components. Their magnetic fields are coupled, allowing enhanced stellar ...

  19. Studying Culicoides vectors of BTV in the post-genomic era: resources, bottlenecks to progress and future directions

    Science.gov (United States)

    Culicoides biting midges (Diptera: Ceratopogonidae) are a major vector group responsible for the biological transmission of a wide variety of globally significant arboviruses, including bluetongue virus (BTV). In this review we examine current biological resources for the study of this genus, with a...

  20. Incorporation of public hospitals: a "silver bullet" against overcapacity, managerial bottlenecks and resource constraints? Case studies from Austria and Estonia.

    Science.gov (United States)

    Fidler, Armin H; Haslinger, Reinhard R; Hofmarcher, Maria M; Jesse, Maris; Palu, Toomas

    2007-05-01

    This paper presents a new approach for incorporating public hospitals by contrasting the experience from an "old" EU country (Austria) with a new EU member state (Estonia). In the EU (including the new member states) hospital overcapacity is a serious problem, from a technical, fiscal and political perspective. Few countries have succeeded in establishing an appropriate framework for resource management and for guaranteeing long-term financial viability of their hospital network. Many countries are in search of effective policies for improved hospital management and more cost-effective resource use in the health sector. Over the past decade, experiences in Austria and Estonia have emerged as innovative examples which may provide lessons for other EU countries and beyond. This paper describes the evolution of public hospitals from public budgetary units and public management to incorporated autonomous organizations under private corporate law, resulting in a contractual relationship between (public) owners and private hospital management. Outdated and inefficient public sector structures were replaced by more agile corporate management. The arrangement allows for investments, operating costs and budgeting according to strategic business goals as opposed to political "fiat". Shielding hospitals from local political influence is an important aspect of this concept. Horizontal integration through networking of public hospitals and introducing private management helps create a new corporate culture, allowing for more flexibility to achieve efficiencies through downsizing and economies of scale. Based on contracts the new balance between ownership and managerial functions create strong incentives for a more business-like, results-oriented and consumer-friendly management. This was achieved both in Austria and Estonia in a politically sensitive way, adopting a long-term vision and by protecting the interests of hospital owners and staff. PMID:16919838

  1. Marine neurotoxins: state of the art, bottlenecks, and perspectives for mode of action based methods of detection in seafood.

    Science.gov (United States)

    Nicolas, Jonathan; Hendriksen, Peter J M; Gerssen, Arjen; Bovee, Toine F H; Rietjens, Ivonne M C M

    2014-01-01

    Marine biotoxins can accumulate in fish and shellfish, representing a possible threat for consumers. Many marine biotoxins affect neuronal function essentially through their interaction with ion channels or receptors, leading to different symptoms including paralysis and even death. The detection of marine biotoxins in seafood products is therefore a priority. Official methods for control are often still using in vivo assays, such as the mouse bioassay. This test is considered unethical and the development of alternative assays is urgently required. Chemical analyses as well as in vitro assays have been developed to detect marine biotoxins in seafood. However, most of the current in vitro alternatives to animal testing present disadvantages: low throughput and lack of sensitivity resulting in a high number of false-negative results. Thus, there is an urgent need for the development of new in vitro tests that would allow the detection of marine biotoxins in seafood products at a low cost, with high throughput combined with high sensitivity, reproducibility, and predictivity. Mode of action based in vitro bioassays may provide tools that fulfil these requirements. This review covers the current state of the art of such mode of action based alternative assays to detect neurotoxic marine biotoxins in seafood. PMID:24311541

  2. 韶关市职业教育的瓶颈及对策探究%The Bottleneck and Countermeasures of Occupational Education in Shaoguan

    Institute of Scientific and Technical Information of China (English)

    王剑兰; 张成林

    2015-01-01

    According to the results of the survey ,the Shaoguan occupational education has achieved remark-able results,but there are needed to solve the problem,such as the free tuition policy,the treatment of teachers is low,the employment problem of graduates of foreign. In order to promote the sustainable development of Shaoguan occupational education,it should actively strive for superior departments to support, tuition assistance policy and expenditure per student funding standards free as soon as possible;the integration of resources ,the quantity and scale of the scientific definition of vocational schools.%调查结果显示,韶关市职业教育取得了显著的成效,但同时存在亟需解决问题,如免学费政策、教师待遇偏低、毕业生外地就业等问题。为促进韶关市职业教育可持续发展,应积极争取上级主管部门的支持;尽快制定本市的免学费补助政策和生均经费拨款标准;整合资源,科学厘定职校的数量和规模。

  3. Paradigm shift in transport legislation or rather at the 'bottleneck'; Paradigmenwechsel im Befoerderungsrecht oder am 'Flaschenhals'

    Energy Technology Data Exchange (ETDEWEB)

    Naeser, Hanns [GNS Gesellschaft fuer Nuklear-Service mbH, Essen (Germany)

    2015-01-15

    In the year just started significant decisions with considerable consequences by the Federal Constitutional Court and the Federal Administrative Court in the field of nuclear law are expected. Especially the decision with regards to 'nuclear phase-out' within the 13th amendment of the Atomic Energy Act is being eagerly expected, as with its far-reaching consequences also fundamental constitutional questions need to be answered. The Federal Administrative Court will need to decide on the question, whether she admits the appeal against the Brunsbuettel decision by the Higher Administrative Court Schleswig-Holstein (HAC), which from the view of claimant shifted the fundamental basis of demarcation of responsibilities between the executive and judiciary power. In comparison to these fundamental decisions the awaited decision by the HAC on nuclear transport legislation seems of subordinate importance, although she will proceed with a paradigm shift in the legal area. The decision deals with the question as to whether and when a right of action from a third party within the nuclear transport legislation can be accepted or more precisely under which preconditions a third party has clear standing against a nuclear transport authorisation. As the site selection law (issued on 23 July 2013 BGBI I p. 2552) excludes the recirculation of vitrified waste block canisters from reprocessing spent fuel elements to the transport cask storage facility Gorleben, the decision by the HAC Lueneburg for this site will only be relevant for present unpredictable transportations from the transport cask storage facility Gorleben to a final repository. If necessary interest to seek a declaratory judgment for declaratory action, in concreto danger of recurrence will be approved, is another matter.

  4. 全民医保亟待打破“十不”瓶颈%“Ten No”Bottlenecks Should Be Broken for Achieving Universal Health Care

    Institute of Scientific and Technical Information of China (English)

    田芬

    2014-01-01

    We have basically achieved the goal of universal health care in China. However, it must be clearly realized that there are still problems such as inconsistence in systems, unclear classification in management departments, non-standardized professional criteria for insurance agencies, non-equivalence in right and duty, non-differentiation in social insurance and commercial insurance, unclear definition of “diseases”, unclear limitation in purchasing service, unclear definition in accessing local or offsite health services, unclear risk prediction, imbalance in demands and supplies, inefficiency in combating insurance fraud, unclear definition in taxes and fees. It is also urgent to accelerate the modernization of administrative system and governance capacity.%我国基本实现全民医保,但必须清醒地看到,目前的全民医保存在着制度不统一、管理归属不明确、经办不标化,权利义务不对等,社保商保不分,对“病”的界定不清,购买服务界线不清,本地异地就医不分,风险预测不清,供需不平衡,对欺诈骗保打击不力,税费不分等问题,亟待加快治理体系和治理能力现代化。

  5. Bottlenecks in the coverage of the Israeli–Palestinian conflict: the coverageof the first and second intifada in the Flemish press

    OpenAIRE

    Deprez, Annelore; Van De Wal, Karin Raeymaeckers

    2011-01-01

    Various authors suggest that the public's knowledge of the Israeli-Palestinian conflict is inadequate. As it is generally accepted that public opinion on international news items is mainly formed by media content, the international media are often held responsible for sustaining the prevailing misconceptions about the Israeli-Palestinian conflict by covering the conflict parties in a biased and imbalanced way. This study focuses on the representation of Israelis and Palestinians in the news c...

  6. Globalization as a Driver or Bottleneck for Sustainable Development: Some Empirical, Cross-National Reflections on Basic Issues of International Health Policy and Management

    Directory of Open Access Journals (Sweden)

    Arno Tausch

    2013-01-01

    Full Text Available BackgroundThis article looks at the long-term, structural determinants of environmental and public health performance in the world system. MethodsIn multiple standard ordinary least squares (OLS regression models, we tested the effects of 26 standard predictor variables, including the ‘four freedoms’ of goods, capital, labour and services, on the following indicators of sustainable development and public health: avoiding net trade of ecological footprint global hectare (gha per person; avoiding high carbon emissions per million US dollars GDP; avoiding high CO2 per capita (gha/cap; avoiding high ecological footprint per capita; avoiding becoming victim of natural disasters; a good performance on the Environmental Performance Index (EPI; a good performance on the Happy Life Years (HLYs scale; and a good performance on the Happy Planet Index (HPI. ResultsOur research showed that the apprehensions of quantitative research, critical of neo-liberal globalization, are fully vindicated by the significant negative environmental and public health effects of the foreign savings rate. High foreign savings are indeed a driver of global footprint, and are a blockade against a satisfactory HPI performance. The new international division of labour is one of the prime drivers of high CO2 per capita emissions. Multinational Corporation (MNC penetration, the master variable of most quantitative dependency theories, blocks EPI and several other socially important processes. Worker remittances have a significant positive effect on the HPI, and HLYs. ConclusionWe re-analysed the solid macro-political and macro-sociological evidence on a global scale, published in the world’s leading peer-reviewed social science, ecological and public health journals, which seem to indicate that there are contradictions between unfettered globalization and unconstrained world economic openness and sustainable development and public health development. We suggest that there seems to be a strong interaction between ‘transnational capitalist penetration’ and ‘environmental and public health degradation’. Global policy-making finally should dare to take the globalization-critical organizations of ‘civil society’ seriously. This conclusion not only holds for the countries of the developed “West”, but also, increasingly, for the growing democracy and civil society movements around the globe, in countries as diverse as Brazil, Russia, China, or ever larger parts of the Muslim world.

  7. Previous Estimates of Mitochondrial DNA Mutation Level Variance Did Not Account for Sampling Error: Comparing the mtDNA Genetic Bottleneck in Mice and Humans

    OpenAIRE

    Wonnapinij, Passorn; Chinnery, Patrick F.; Samuels, David C

    2010-01-01

    In cases of inherited pathogenic mitochondrial DNA (mtDNA) mutations, a mother and her offspring generally have large and seemingly random differences in the amount of mutated mtDNA that they carry. Comparisons of measured mtDNA mutation level variance values have become an important issue in determining the mechanisms that cause these large random shifts in mutation level. These variance measurements have been made with samples of quite modest size, which should be a source of concern becaus...

  8. Analysis of the Bottleneck of SME Financing and Countermeasures%中小企业融资瓶颈及对策分析

    Institute of Scientific and Technical Information of China (English)

    周艳

    2011-01-01

    SME financing is a world-class problem,so our government should reform the credit, at the same time the SMEs should optimize the financing environment for SMEs, improve credit rating, and broaden financing channels to raise more funds for construction.%中小企业融资难是世界级难题,为此我国政府应该力求信贷改革;同时中小企业也要优化融资环境,提高信用等级,拓宽融资渠道募集更多的资金.

  9. Breaking the bottleneck: Use of molecular tailoring approach for the estimation of binding energies at MP2/CBS limit for large water clusters

    Science.gov (United States)

    Singh, Gurmeet; Nandi, Apurba; Gadre, Shridhar R.

    2016-03-01

    A pragmatic method based on the molecular tailoring approach (MTA) for estimating the complete basis set (CBS) limit at Møller-Plesset second order perturbation (MP2) theory accurately for large molecular clusters with limited computational resources is developed. It is applied to water clusters, (H2O)n (n = 7, 8, 10, 16, 17, and 25) optimized employing aug-cc-pVDZ (aVDZ) basis-set. Binding energies (BEs) of these clusters are estimated at the MP2/aug-cc-pVNZ (aVNZ) [N = T, Q, and 5 (whenever possible)] levels of theory employing grafted MTA (GMTA) methodology and are found to lie within 0.2 kcal/mol of the corresponding full calculation MP2 BE, wherever available. The results are extrapolated to CBS limit using a three point formula. The GMTA-MP2 calculations are feasible on off-the-shelf hardware and show around 50%-65% saving of computational time. The methodology has a potential for application to molecular clusters containing ˜100 atoms.

  10. A recent bottleneck in the warthog and elephant populations of Queen Elizabeth National Park, revealed by a comparative study of four mammalian species in Uganda national parks

    DEFF Research Database (Denmark)

    Muwanika, Vincent B.; Siegismund, Hans Redlef; Okello, John Bosco A.;

    2003-01-01

    varied in the different parks across different animal species. We have investigated the genetic effects of these reductions in four mammalian species (the common warthog, African savannah elephant, savannah buffalo and common river hippopotamus) from the three major parks of Uganda using both...... elephant (mean He 0.68-0.72). We interpret these results in terms of varying poaching pressure in the different parks, susceptibility of different species to poaching and differences in effective population sizes at the mitochondrial and nuclear loci....

  11. Extracellular Electron Transfer Is a Bottleneck in the Microbiologically Influenced Corrosion of C1018 Carbon Steel by the Biofilm of Sulfate-Reducing Bacterium Desulfovibrio vulgaris.

    Directory of Open Access Journals (Sweden)

    Huabing Li

    Full Text Available Carbon steels are widely used in the oil and gas industry from downhole tubing to transport trunk lines. Microbes form biofilms, some of which cause the so-called microbiologically influenced corrosion (MIC of carbon steels. MIC by sulfate reducing bacteria (SRB is often a leading cause in MIC failures. Electrogenic SRB sessile cells harvest extracellular electrons from elemental iron oxidation for energy production in their metabolism. A previous study suggested that electron mediators riboflavin and flavin adenine dinucleotide (FAD both accelerated the MIC of 304 stainless steel by the Desulfovibrio vulgaris biofilm that is a corrosive SRB biofilm. Compared with stainless steels, carbon steels are usually far more prone to SRB attacks because SRB biofilms form much denser biofilms on carbon steel surfaces with a sessile cell density that is two orders of magnitude higher. In this work, C1018 carbon steel coupons were used in tests of MIC by D. vulgaris with and without an electron mediator. Experimental weight loss and pit depth data conclusively confirmed that both riboflavin and FAD were able to accelerate D. vulgaris attack against the carbon steel considerably. It has important implications in MIC failure analysis and MIC mitigation in the oil and gas industry.

  12. From "Migrant Workers Boom" to "Migrant Workers Scarcity"——Analysis of Institutional Bottleneck of Rural Surplus Labors Transfer in China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Through description of three-steps characteristic of dual economic theory and its practical significance to the process of industrialization and urbanization in China,and making comparative analysis between important criterion of "Lewis turning point" and current situation of rural surplus labors market in China,we can find that there exists a great deal of surplus labors in rural areas in our country,improvement of peasant income is the result of external interference of government,and demographic dividend in our country hasn’t finished.These phenomena go against the theory of "Lewis turning point".So it can prove that "Lewis turning point" in China hasn’t come yet.The paper points out the major factors of coexistence of "migrant workers scarcity" and labors redundancy in our country.The first one is structure contradiction of labors market;the second one is law of supply-demand of labors market;the third one is institutional barrier which hinders labors in free flow of census register and social guarantee.Therefore,if we want to realize successful transfer of rural surplus labors and the goal of industrialization and urbanization,we must promote upgrading of industrial structure,change the style of economic growth and realize harmonious development of regional economy in macrocosmic level;And in microcosmic level,we should eliminate institutional barrier which hinders transfer of rural surplus labors.

  13. Realizing the Now-or-Never bottleneck and Chunk-and-Pass processing with Item-Order-Rank working memories and masking field chunking networks.

    Science.gov (United States)

    Grossberg, Stephen

    2016-01-01

    Christiansen & Chater's (C&C's) key goals for a language system have been realized by neural models for short-term storage of linguistic items in an Item-Order-Rank working memory, which inputs to Masking Fields that rapidly learn to categorize, or chunk, variable-length linguistic sequences, and choose the contextually most predictive list chunks while linguistic inputs are stored in the working memory. PMID:27561607

  14. The Bottleneck and Solution of Chinese Folk Sports Culture Development%我国民俗体育文化发展瓶颈与解决策略

    Institute of Scientific and Technical Information of China (English)

    何丽琴

    2014-01-01

    Sports is one of the traditional project activities in China for thousands of years , its historical position and function are very important .The folk sports culture in sports , its development status is not optimistic .A lot of people without a conscious of protecting and inheriting the attitude to the sports culture , together with the relevant laws and regulations on state is not perfect , caused by a considerable impact on the development of these cultural . Many business Companies take folk sports culture to increase their business economic benefits of gimmicks , only pay attention to the value of economy , ignoring its cultural value and cultural value .To solve these problems , we must formulate relevant policies to protect the folk sports culture .%体育运动是我国几千年来的传统活动项目之一,其历史地位和作用都非常重要。而对于体育中的民俗体育文化来讲,其发展现状不容乐观。很多民众对于这种体育文化没有一种自觉的保护和传承的态度,再加上国家的相关法律法规也不完善,导致了这些文化的发展受到了相当大的影响。很多的商业公司将民俗的体育文化作为增加自己商业经济效益的噱头,只注重挖掘其经济方面的价值,忽视了其文化方面的价值以及人文方面的价值。针对这些问题,我们必须制定相关的政策来保护民俗体育文化。

  15. Research on the Reasons of E-commerce Logistics Bottleneck%电子商务中物流瓶颈成因研究

    Institute of Scientific and Technical Information of China (English)

    熊晓艳

    2013-01-01

    The development of electronic commerce has gradually changed the way we work and live, making it more convenient, flexible and comfortable, especially in access to information, information transmission, and all kinds of service activities, payment, shipping method, etc. But because China is a developing country which has entered directly into the information society without experiencing the developed industrial civilization, the development of e-business is faced with severe challenges and tests.%电子商务的发展已经逐步改变了我们的工作和生活方式,使其更加方便、灵活和自如。尤其是在获取信息、传输信息、各种服务活动、付款、送货方式等方面。但由于我国是一个没有经历发达工业文明而直接进入信息社会的发展中国家,电子商务在发展过程中面临着各种严峻的挑战和考验。

  16. The Norwegian hydropower : what are the drivers and bottlenecks of the small hydropower industry, and how will these further affect the development?

    OpenAIRE

    Thomassen, Eivind Blankenberg

    2013-01-01

    The small hydropower industry in Norway is in a critical phase. The el-certificates system has proven to be a strong driver for new hydropower plants, as well as investments in existing plants, but with this system comes uncertainty regarding future revenue and profits. In addition to uncertainties connected to incentives, the price of electricity has fluctuated the past decade, fueling and dampening new investments with its movements. Strict acts and regulations concerning the utilization of...

  17. Renewable marine energies, state of the art, technological bottlenecks and perspectives; Les energies marines renouvelables, etat de l'art, verrous technologiques et perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Marchand, Ph. [Centre IFREMER Dir., 29 - Brest (France)

    2011-05-15

    The ocean is a huge reservoir of energy that is very little worked. This article reviews the different ways to use the energy stored in the ocean: -) thermal energy, -) the energy of the ocean streams, -) the energy of the tides, -) the energy of the waves, and -) the off-coast wind energy. This article reviews the different projects throughout the world, the potentialities of such energies and the technical challenges to overcome. (A.C.)

  18. Removing the taint : bottlenecks and possible directions for a solution in the marketing of the meat of non-castrated male pigs

    NARCIS (Netherlands)

    Klep, L.M.F.

    2008-01-01

    Onderzoeksresultaten laten zien dat het onwaarschijnlijk is dat er een eenvoudige oplossing bestaat voor het stoppen met castratie van beertjes in de varkenshouderij. Er dient gezocht te worden naar een combinatie van verschillende methoden. De berengeurproblematiek is primair een probleem van markt

  19. System Inadequacy: Bottleneck of the Development of Chinese Librarianship%制度缺位:中国图书馆事业发展的瓶颈

    Institute of Scientific and Technical Information of China (English)

    蒋永福

    2006-01-01

    图书馆立法缺位、职业自律制度缺位、职业权益保障制度缺位和职业准入制度缺位,是阻碍中国图书馆事业发展的瓶颈.制度缺位必然带来职责的缺位和功能的缺位.

  20. Divided infraorbital foramen in the lion (Panthera leo): its implications for colonisation history, population bottlenecks, and conservation of the Asian lion (P. l. persica)

    OpenAIRE

    Yamaguchi, N; Kitchener, A.C.; Driscoll, C.A.; Macdonald, D. W.

    2009-01-01

    A divided infraorbital foramen is an important morphological feature in lion taxonomy and has previously been considered to occur only in the Asian lion, Panthera leo persica. Based on an examination of 498 lion skulls from museum collections in Europe and southern Africa, we report for the first time on the prevalence of the divided infraorbital foramen in African lions, as well as its occurrence in the tiger, P. tigris and the extinct Pleistocene European cave lion, P. leo spelaea. The high...

  1. Legal concepts to eliminate the bottleneck in energy-saving modernisations for existing buildings; Rechtskonzepte zur Beseitigung des Staus energetischer Sanierungen im Gebaeudebestand

    Energy Technology Data Exchange (ETDEWEB)

    Klinski, Stefan [Hochschule fuer Wirtschaft und Recht (HWR), Berlin (Germany)

    2009-10-15

    The research project looked at the following: 1. Whether and to what extent the German tenancy law creates, on the one hand, adequate incentives for energy-saving modernisations of existing buildings, on the one hand, and, on the other, whether it creates legal obstacles. 2. How these obstacles could be eliminated i.e. by changing existing tenancy law and instead creating stimuli for energy-saving modernization of existing rental buildings. The report contents a number of specific recommendations for an energy-related reform of the German tenancy law. Major recommendations are: - to eliminate the current toleration duty for modernisation measures if changes are made to the building that conflict with the duties arising from the energy saving provisions of public law, - to consider energy-saving characteristics in the reference rent customary in the locality, - to create a possibility for imposing a flat-rate surcharge which is linked to the savings in heating costs for energy-saving improvement. (orig.)

  2. Beyond a Mask and Against the Bottleneck: Retroactive Dual-Task Interference During Working Memory Consolidation of a Masked Visual Target

    NARCIS (Netherlands)

    Nieuwenstein, Mark; Wyble, Brad

    2014-01-01

    While studies on visual memory commonly assume that the consolidation of a visual stimulus into working memory is interrupted by a trailing mask, studies on dual-task interference suggest that the consolidation of a stimulus can continue for several hundred milliseconds after a mask. As a result, es

  3. “Ten No”Bottlenecks Should Be Broken for Achieving Universal Health Care%全民医保亟待打破“十不”瓶颈

    Institute of Scientific and Technical Information of China (English)

    田芬

    2014-01-01

    我国基本实现全民医保,但必须清醒地看到,目前的全民医保存在着制度不统一、管理归属不明确、经办不标化,权利义务不对等,社保商保不分,对“病”的界定不清,购买服务界线不清,本地异地就医不分,风险预测不清,供需不平衡,对欺诈骗保打击不力,税费不分等问题,亟待加快治理体系和治理能力现代化。%We have basically achieved the goal of universal health care in China. However, it must be clearly realized that there are still problems such as inconsistence in systems, unclear classification in management departments, non-standardized professional criteria for insurance agencies, non-equivalence in right and duty, non-differentiation in social insurance and commercial insurance, unclear definition of “diseases”, unclear limitation in purchasing service, unclear definition in accessing local or offsite health services, unclear risk prediction, imbalance in demands and supplies, inefficiency in combating insurance fraud, unclear definition in taxes and fees. It is also urgent to accelerate the modernization of administrative system and governance capacity.

  4. From “Migrant Workers Boom†to “Migrant Workers Scarcity†—Analysis of Institutional Bottleneck of Rural Surplus Labors Transfer in China

    OpenAIRE

    Wang, Qin

    2010-01-01

    Through description of three-steps characteristic of dual economic theory and its practical significance to the process of industrialization and urbanization in China, and making comparative analysis between important criterion of "Lewis turning point" and current situation of rural surplus labors market in China, we can find that there exists a great deal of surplus labors in rural areas in our country, improvement of peasant income is the result of external interference of government, and d...

  5. 突破素质瓶颈,加快龙岩市农村妇女劳动力转移%Breaking through the quality bottleneck and speeding up migration of rural women labour force in Longyan

    Institute of Scientific and Technical Information of China (English)

    刘淑兰; 郑逸芳

    2005-01-01

    本文分析了龙岩市农村妇女劳动力转移的基本状况以及素质对妇女劳动力转移就业的制约,强调加强男女平等宣传、农村基础教育、职业教育和就业服务等对于突破素质瓶颈、加快龙岩市农村妇女富余劳动力转移的重要意义.

  6. 制造业突破库存管理瓶颈的方法及实证研究%Manufacturing Breakthroughs Inventory Management Bottleneck Method and Empirical Research

    Institute of Scientific and Technical Information of China (English)

    董鹏; 郭丽美

    2013-01-01

    At present through the analysis of domestic manufacturing inventory status and management ideas, to find the United States of America Carlisle companies finished inventory backlog of reason and the backlog of inventory to the production and operation of enterprises brought bad influence. Combined with examples of Calais companies to reduce inventory, points out that the application of management by objectives, fishbone diagram, ABC classification management tool, is the most effective method to reduce the inventory. This succeeded in reducing inventory, related to the manufacturing industry for effective inventory management to provide reference.%  要:通过分析目前国内制造业的库存现状及管理思路,找出美国卡莱公司造成成品库存积压的原因及库存积压给企业生产经营带来的不良影响。结合卡莱公司降低库存的实例,指出运用目标管理、鱼骨图、ABC分类等管理工具,是降低库存的最有效方法。本次成功地降低了库存量,为相关制造业进行有效的库存管理提供借鉴。

  7. On the elimination of the electronic structure bottleneck in on the fly nonadiabatic dynamics for small to moderate sized (10-15 atom) molecules using fit diabatic representations based solely on ab initio electronic structure data: The photodissociation of phenol

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Xiaolei, E-mail: virtualzx@gmail.com; Yarkony, David R., E-mail: yarkony@jhu.edu [Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218 (United States)

    2016-01-14

    In this work, we demonstrate that for moderate sized systems, here a system with 13 atoms, global coupled potential energy surfaces defined for several electronic states over a wide energy range and for distinct regions of nuclear coordinate space characterized by distinct electron configurations, can be constructed with precise energetics and an excellent description of non-adiabatic interactions in all regions. This is accomplished using a recently reported algorithm for constructing quasi-diabatic representations, H{sup d}, of adiabatic electronic states coupled by conical intersections. In this work, the algorithm is used to construct an H{sup d} to describe the photodissociation of phenol from its first and second excited electronic states. The representation treats all 33 internal degrees of freedom in an even handed manner. The ab initio adiabatic electronic structure data used to construct the fit are obtained exclusively from multireference configuration interaction with single and double excitation wave functions comprised of 88 × 10{sup 6} configuration state functions, at geometries determined by quasi-classical trajectories. Since the algorithm uses energy gradients and derivative couplings in addition to electronic energies to construct H{sup d}, data at only 7379 nuclear configurations are required to construct a representation, which describes all nuclear configurations involved in H atom photodissociation to produce the phenoxyl radical in its ground or first excited electronic state, with a mean unsigned energy error of 202.9 cm{sup −1} for electronic energies <60 000 cm{sup −1}.

  8. 我国城乡教师交流的演变、瓶颈及策略%On the Evolution,Bottlenecks and Strategies of Teachers’ Exchange Between Urban and Rural Schools in China

    Institute of Scientific and Technical Information of China (English)

    虎技能

    2015-01-01

    我国城乡教师交流经历了从单向支援向双向轮岗演变的过程,政府、学校、教师等参与主体存在的一些问题制约着城乡教师交流的发展。采取明确交流主体的责任、完善监督评估机制、提高教师的思想认识、补偿教师的利益损失、加强交流机制的理论研究等措施,将有利于进一步推进城乡教师交流。%In China ,the teachers’ exchange between urban and ruralschools has evaluated to bi‐lateral exchange from unilateral support .The problems of government ,schools ,teachers ,and so on have restricted the development of teachers’ exchange between urban and rural schools .In order to strengthen teachers’ communication between rural and urban schools ,the following measures should be taken:to conduct definite communicative responsibility ,to improve the supervision and evaluation mechanism ,to raise the teachers’ ideological understanding ,to compensate teachers’ loss of interest , and to enhance the study of the exchange mechanism theory ,etc .

  9. Breakthrough of the p-type doping bottleneck in ZnO by inserting an ultrathin ZnX (X  =  S, Se and Te) layer doped with NX or AgZn

    Science.gov (United States)

    Jiang, Xin-he; Shi, Jun-jie; Zhang, Min; Zhong, Hong-xia; Huang, Pu; Ding, Yi-min; Cao, Xiong; Wu, Meng; Liao, Zhi-min

    2016-03-01

    The worldwide problem of p-type doping in ZnO is investigated based on first-principles calculations by combining the standard density functional theory and hybrid functional methods. We find that p-type doping can be realized by inserting an ultrathin ZnX (X  =  S, Se and Te) layer, doped with NX or AgZn, into ZnO to form short-period (ZnO) m /(ZnX) n (m  >  n) superlattices. The formation energy is the lowest for NX or AgZn in the ZnX layer. The Zn-rich (Zn-poor) condition is favourable for the formation of the NX (AgZn) defect. Compensation by the native defects can be avoided for the Ag-doped (ZnO) m /(ZnX) n under the Zn-poor condition. The N (Ag) acceptor activation energy can be reduced from 0.45 (0.43) eV in ZnO to 0.33 (0.32) eV in (ZnO)5/(ZnS)1, 0.20 (0.24) eV in (ZnO)5/(ZnSe)1 and 0.12 (0.13) eV in (ZnO)5/(ZnTe)1, which is caused by the ZnX-monolayer modulation to the local structure around the NX or AgZn defect and the high-lying p-derived valence bands. Moreover, the band gaps can be tuned from 3.40 eV of ZnO to 3.21 eV of (ZnO)5/(ZnS)1, 2.41 eV of (ZnO)5/(ZnSe)1 and 2.26 eV of (ZnO)5/(ZnTe)1, which is promising for the integration of ZnO-based white light-emitting diodes.

  10. Breakthrough of the p-type doping bottleneck in ZnO by inserting an ultrathin ZnX (X  =  S, Se and Te) layer doped with NX or AgZn

    International Nuclear Information System (INIS)

    The worldwide problem of p-type doping in ZnO is investigated based on first-principles calculations by combining the standard density functional theory and hybrid functional methods. We find that p-type doping can be realized by inserting an ultrathin ZnX (X  =  S, Se and Te) layer, doped with NX or AgZn, into ZnO to form short-period (ZnO)m/(ZnX)n (m  >  n) superlattices. The formation energy is the lowest for NX or AgZn in the ZnX layer. The Zn-rich (Zn-poor) condition is favourable for the formation of the NX (AgZn) defect. Compensation by the native defects can be avoided for the Ag-doped (ZnO)m/(ZnX)n under the Zn-poor condition. The N (Ag) acceptor activation energy can be reduced from 0.45 (0.43) eV in ZnO to 0.33 (0.32) eV in (ZnO)5/(ZnS)1, 0.20 (0.24) eV in (ZnO)5/(ZnSe)1 and 0.12 (0.13) eV in (ZnO)5/(ZnTe)1, which is caused by the ZnX-monolayer modulation to the local structure around the NX or AgZn defect and the high-lying p-derived valence bands. Moreover, the band gaps can be tuned from 3.40 eV of ZnO to 3.21 eV of (ZnO)5/(ZnS)1, 2.41 eV of (ZnO)5/(ZnSe)1 and 2.26 eV of (ZnO)5/(ZnTe)1, which is promising for the integration of ZnO-based white light-emitting diodes. (paper)

  11. Bottlenecks analysis and countermeasures studying in the implementation of family doctor service system%推行家庭医生服务的瓶颈问题分析与对策研究

    Institute of Scientific and Technical Information of China (English)

    申美霞; 杨兴平; 郑文新

    2013-01-01

    目的:通过深圳市福田区开展家庭医生服务存在的问题提出对策。方法:于2011年11月1日~12月1日通过调查问卷及电话随访等方式,对深圳市福田区10家社区健康服务中心开展家庭医生制服务状况进行调查。结果:目前福田区家庭医生服务取得了较大的发展,家庭医生团队建设不断加强、绩效考核体系逐步完善,有开展家庭医生服务的基础;但存在家庭医生人力资源不足、医疗服务水平参差不齐,导致居民不信任,居民传统的医疗观念及卫生政策不配套也影响了新模式的推行。结论:建议在政府主导下加大政策扶持力度,明确工作目标,完善细化工作内容,加强家庭医生人才培养与培训及家庭医生责任服务模式的宣传、科学开展家庭医生制服务绩效评估等。%Objective:To table countermeasures to the problems existing in the Family Doctor Service System in Futian District , Shenz-hen.Methods:Conducted questionnaire surveys and telephone interviews among ten Community Health Centers undergoing Family doctor System in Futian District, Shenzhen (2011.11.1-12.1).Results:Family Doctor Service in Futian District had presently made relatively large headway in improving family doctors team building and performance appraisal system , which lay the foundation for the implementa-tion of Family Doctor Service , however , family doctors scarcity and irregular -leveled medical services result in local residents'trust drought;meanwhile , traditional medical perceptions and lack of supporting health policy slowed the implementation .Conclusion:The re-sults suggested that strengthening government -led supportive policy execution and system personnel training , classifying the work targets , detailing the work tasks , propagandizing responsibility -system service mode and science performance evaluations were the extremely ur -gency to save .

  12. 民族传统体育高脚马运动发展瓶颈分析%On Bottlenecks of Development of Chinese Minority Traditional Sports Event "Horse on Stilts"

    Institute of Scientific and Technical Information of China (English)

    陈辉

    2012-01-01

    Chinese minority traditional sports event "Horse on Stilts" through a decade of development, the speed isamazing. 100 m and 200 m performance level has been running close to or above the results, but fn the relay rules of project requirements and project settings for a single, always influence and restrict "Horse on Stilts" sports development space. According to previous project of the national democratic movement's "Horse on Stilts" relay performance analysis,combination with Hong he Pl:efecture of Yunnan province athletes run and "horse on stilts" run'to the tests, As welu as in "horse on stilts" project settings on thinking. The current "Horse on Stilts" relay race rules, the project set up research and analysis, attempt to explore the development of "Horse on Stilts" movement favorable factors, and the formation of scientific theory to guide the development of "Horse on Stilts" movement.%民族传统体育高脚马运动在近十年的竞技发展中,其发展速度是惊人的,100米和200米成绩已接近甚至超过了平跑成绩,但接力跑项目的规则要求和项目设置的单一,始终影响和制约着高脚马运动发展的空间,笔者根据历届全国民运会高脚竞速接力项目成绩的分析,并结合云南省红河州高脚竞速运动员平跑与高脚跑的各项测试,以及在高脚马项目设置上的思考,对现有高脚竞速接力跑竞赛规则、项目设置进行研究分析,试图探索出高脚马运动发展的有利因素,并形成科学理论指导高脚马运动的发展。

  13. Research on the Bottleneck Problem of China’s Cross-Border Electronic Commerce%中国跨境电子商务发展的“痛点”分析

    Institute of Scientific and Technical Information of China (English)

    文瑞

    2015-01-01

    近年来,随着经济全球化和电子商务的快速发展,跨境电子商务成为国际贸易的新方式。相较于传统贸易,中国跨境电子商务交易规模不断扩大,并保持连续性的高速增长,但同时,跨境电子商务也面临着诸如支付、物流、报关、商检、售后等诸多“痛点”。因此,亟需通过建设跨境电子商务产业园区,创新跨境物流服务,发挥跨境创牌优势,培养全面发展型人才,重构跨境电子商务适用规则等措施来推动中国跨境电子商务进一步的发展。%Recently,cross-border e-commerce became the new way of international trade with economic globalization and the rapid development of electronic commerce. Compared with the traditional trade,China’s cross-border e-commerce transactions expand continually and keep the continuous high-speed growth. At the same time,cross-border e-commerce is faced with some pain points such as payment,logistics,customs clearance,commodity inspection and after sales. Therefore, we urgently need to take some measures,like the construction of cross-border e-commerce industrial park,cross-border logistics service innovation,giving full play to the advantages of cross-border brand,cultivating comprehensive talent, refactoring applicable cross-border e-commerce rules,so as to promote the further development of Chinese cross-border electronic commerce.

  14. The Analysis of "Bottleneck" Structural Model on Constructing Ecological Interpersonal Relation inside Enterprises%企业内部生态人际的"瓶状"结构模型剖析

    Institute of Scientific and Technical Information of China (English)

    黄江泉; 蔡根女

    2009-01-01

    结合一些著名学者对影响企业人际关系的因素分析,文章梳理出人际距离等影响企业入际关系发展的七个最基本要素,并深入分析、比较了它们在企业内部人际关系构成中的地位与作用.在此基础上,构造了一个结构形象、层次分明的"瓶状"人际结构模型,为企业建设、发展生态人际提供一定的指导.

  15. Analysis of the Bottleneck Problem with Patent Marketization Mechanism at Application-Oriented Colleges and Universities in China%应用型工程院校专利市场化机制的瓶颈分析

    Institute of Scientific and Technical Information of China (English)

    李颖

    2014-01-01

    Nowadays,there are some problems with the patent marketization mechanism of China”s application-centered colle-ges and universities,for example,unclear targets,imperfect system for administration resource distribution,and unreasonable scientific and technological information service system.It is,therefore,advisable to improve the mechanism for patent mar-ketization under the guidance of the present patent marketization target,in order to develop core advantages and continuously boost the patent value.This is aimed at developing samples of patent marketization system at application-centered colleges and universities.%目前,我国现行应用型工程院校专利市场化机制存在专利市场化目标定位模糊、管理资源配置制度不完善、科技信息服务制度不合理、考核激励制度缺失等不足。需在现行专利市场化目标的指导下,完善其专利市场化机制,以期能紧扣关键、凝炼优势、聚焦瓶颈、持续增值,从而打造应用型工程院校专利市场化机制的范本。

  16. 我国飞机租赁融资的发展障碍与解决之道%Bottlenecks of Aircraft Lease Financing in China and Potential Measures to Address them

    Institute of Scientific and Technical Information of China (English)

    王振; 彭爽

    2006-01-01

    @@ 中国航空运输业和飞机租赁市场的发展特点 一是中国航空运输业近年来一直保持高速增长的态势.2005年中国民航的旅客运输量创下了有史以来的最高记录,达到了1.38亿人次,货邮运输量306.7万吨,完成运输总周转量261.3亿吨公里.截止到 2005年底,我国定期航班航线达到1200条,其中国内航线(包括香港、澳门航线)975条,国际航线225条,境内民航定期航班通航机场135个(含香港、澳门),形成了以北京、上海、广州机场为中心,以省会、旅游城市机场为枢纽,其他城市机场为支干,联结国内133个城市,国际38个国家80个城市的航空运输网络.

  17. On the elimination of the electronic structure bottleneck in on the fly nonadiabatic dynamics for small to moderate sized (10-15 atom) molecules using fit diabatic representations based solely on ab initio electronic structure data: The photodissociation of phenol

    International Nuclear Information System (INIS)

    In this work, we demonstrate that for moderate sized systems, here a system with 13 atoms, global coupled potential energy surfaces defined for several electronic states over a wide energy range and for distinct regions of nuclear coordinate space characterized by distinct electron configurations, can be constructed with precise energetics and an excellent description of non-adiabatic interactions in all regions. This is accomplished using a recently reported algorithm for constructing quasi-diabatic representations, Hd, of adiabatic electronic states coupled by conical intersections. In this work, the algorithm is used to construct an Hd to describe the photodissociation of phenol from its first and second excited electronic states. The representation treats all 33 internal degrees of freedom in an even handed manner. The ab initio adiabatic electronic structure data used to construct the fit are obtained exclusively from multireference configuration interaction with single and double excitation wave functions comprised of 88 × 106 configuration state functions, at geometries determined by quasi-classical trajectories. Since the algorithm uses energy gradients and derivative couplings in addition to electronic energies to construct Hd, data at only 7379 nuclear configurations are required to construct a representation, which describes all nuclear configurations involved in H atom photodissociation to produce the phenoxyl radical in its ground or first excited electronic state, with a mean unsigned energy error of 202.9 cm−1 for electronic energies <60 000 cm−1

  18. Dynamic Characteristics of Explicit Control Protocol

    Institute of Scientific and Technical Information of China (English)

    CHENG Shuang-mei; LI Jian-hua; GUO Chuan-xiong

    2008-01-01

    The dynamic characteristics of eplicit control protocol (XCP) were investigated with single bottle-neck on the microscopic time-scale. Analysis and simulation results show that the bandwidth utilization of an XCP bottleneck link converges to 1 at exponential rate, persistent congestion cannot occur at the bottleneck link, and throughput of an arbitrary subset of XCP flows at the bottleneck link converges to its fair share in exponential rate. The XCP has high bandwidth utilization and good fairness properties.

  19. 我国第三方物流发展瓶颈与营销策略的创新——4Ps理论在物流行业的运用%China's Third Party Logistics Development Bottleneck and the Innovation of the Marketing Strategy——4Ps theory use in the logistics industry

    Institute of Scientific and Technical Information of China (English)

    郑文玲

    2014-01-01

    近年来,我国经济取得突飞猛进的发展,产业结构获得了升级与优化,物流行业特别是第三方物流行业在我国经济发展中的地位越来越重要.然而,由于起步较晚、经验不足,我国第三方物流还存在很多缺陷.在对第三方物流业的现状与发展瓶颈进行分析的基础上,以市场营销学经典理论——4Ps战略模型对我国第三方物流企业的发展提供了一个可以借鉴的改进方案.

  20. 论参与式预算实施的现实瓶颈及其在我国的构建——兼谈我国《预算法》的修改及完善%The Real Bottleneck of Implement of Participatory Budgeting and its Construction in China-on the Modification and Perfection of Budget Law

    Institute of Scientific and Technical Information of China (English)

    王婷婷

    2013-01-01

    当前,参与式预算已经作为一种公民直接参与预算决策过程以提高预算民主的一种重要方式而广泛运用于各国的预算管理实践中,然而,参与预算的实践和试点并未实质性地推动我国立法的改变,在我国的《预算法》及其《修正案》中未对公民在预算过程中的权利进行规定,政府占据了过宽的预算平台而忽视了公民参与预算的重要意义.因此,在借鉴国际参与式预算经验,总结我国实践的基础上,以我国《预算法》的修改为契机构建完善的参与式预算机制极为必要.

  1. 社会转型与工会使命——全球化背景下中国工会的艰难困局及其瓶颈突破%Social Transformation and Mission of Trade Unions——Difficult Predicament of China's Trade Unions and Their Bottleneck Breakthrough Under the Background of Globalization

    Institute of Scientific and Technical Information of China (English)

    王天林

    2010-01-01

    在全球化背景下,国际工运出现了积极应对的发展趋势,而中国工会却面临着组织庞大与发挥作用极不相称的艰难困局.过去三十年的发展,中国在实现了国民经济快速崛起的同时,也成为国际垄断资本任意游走的场地,以劳动者的"低人权优势"为代价迎接了西方国家的产业转移,劳工经数百年斗争赢得的权利与福利成果以及劳资平衡的格局,在中国面临着全面崩塌的危险.面对全球化的挑战和国内劳工保护现状的要求,中国工会必须正视导致自己艰难困局的根源,明确自己的社会定位,在效率公平、经济发展与社会进步的进程中,突出公平,强调工人参与分享社会进步的成果,切实担负起自己在社会转型和全球化过程中的历史使命.

  2. When Open Architecture Beats Closed: The Entrepreneurial Use of Architectural Knowledge

    OpenAIRE

    Baldwin, Carliss Y.

    2010-01-01

    This paper describes how entrepreneurial firms can use superior architectural knowledge to open up a technical system to gain strategic advantage. The strategy involves, first, identifying "bottlenecks" in the existing system, and then creating a new open architecture that isolates the bottlenecks in modules and allows others to connect to the system at key interfaces. An entrepreneurial firm with limited financial resources can then focus on supplying superior bottleneck modules, and while o...

  3. The mechanism and operating system to solve the bottleneck of the cooperation among industry, university and research institute, and the revelation of the mechanism and operating system of finland national technical research centre to Chinese circumstance%突破产学研运行瓶颈的机制设计——芬兰国家研究中心运行机制及对我国的启示

    Institute of Scientific and Technical Information of China (English)

    朱杉; 陈洁

    2009-01-01

    通过时芬兰国家技术研究中心(Technical Research Centre简称VTT)功能角色定位的研究,深入分析了VTT的运行机制,研究总结了VTT解决芬兰产学研结合瓶颈问题的关键原因是其独特的角色定位与运行机制设计,指出了VTT在科技创新体系中所发挥的效用以及值得我圆借鉴的一些启示.

  4. The Bottleneck and Breakthrough of Administrative Discretion’s Abusing Judicial Review--No. 5 and No. 54 of“Administrative Procedure”Law as the Research Objects%行政裁量权滥用司法审查的瓶颈与突破--兼以《行政诉讼法》第5条与第54条为研究对象

    Institute of Scientific and Technical Information of China (English)

    盛玉国

    2014-01-01

    “裁量权像斧子一样,当正确使用时是件工具,它也可能成为伤害或谋杀的凶器”[1]。行政裁量权所具有的主观性、灵活性和选择性的特点决定着其存在滥用的风险,所以应当对行政裁量权进行合理规制。上个世纪90年代,我国初步建立行政裁量权滥用的司法审查制度,但模糊的审查标准导致行政裁量权滥用的司法审查常被“束之高阁”。文章首先阐明行政裁量权滥用司法审查所面临的困境,分析造成这种困境的根源。并在尊重行政裁量权价值的基础上,确立合理性审查原则、比例原则和行政裁量权滥用的情形,以此进一步完善行政裁量权滥用的司法审查制度。%Administrative discretion is like an axe,which is a tool when used correctly. Otherwise,it maybe becomes the dangerous weapon of injury or murder. The features of its subjectivity ,flexibility and selectivity determine its abusing risk ,so it should be reasonably limited. In the 90's of 20th century,our country initially established the judicial review system of the abuse of administrative discretion,but unclear review criteria made it put on the shelf. This paper firstly expounds the plight of administrative discretion’s abusing judicial review and analyses its causes. And based on the respect of administrative discretion value,it establises reasonable review principles,proportion principles and the circumstances of administrative discretion abuse,in order to further improve the judicial review system of the abuse of administrative discretion .

  5. 青年社会组织参与城市社区治理:发展形势、问题瓶颈与推进路径--基于上海青年社会组织社区参与的调查%The Development Situation,Bottleneck Problem and Pushing Approach for the Youth Social Organizations to Participate in the Urban Community Governance:Based on the Research of Shanghai Youth Social Organizations in Community Participation

    Institute of Scientific and Technical Information of China (English)

    刘春蕾

    2016-01-01

    青年社会组织有活力、敢创新,是推进城市基层社区治理的重要力量。上海青年社会组织在参与社区治理过程中融入协同治理思维,面对着“活动领域入基层、参与内容合需求、社会责任能支撑、共青组织善引领、网络媒体搭平台”的发展形势,但也面临着主体待发育、基层欠信任、关系待理顺、政策欠优化、平台不完善等挑战。进一步深化改革是保证青年社会组织社区参与的关键,要做到发育主体、形塑信任、凝聚共识、调整结构、完善政策、搭好平台,构建起平等协作的参与新模式,形成互利共赢的发展新格局。%Dynamic and innovative Youth Social Organizations are an important force in urban grass-roots community governance.According to the field investigation data,Shanghai youth organizations have been integrated into the thought of synergistic governance in the process of community governance partici-pation.Their activities have entered into the grass-roots community .Their participating contents can meet the demand and their social responsibilities can be supported.The communist youth league is good at leading,network media also provides the platform.They also faced some challenges mainly including:subj ect remains to develop;grassroots lack of trust;relationship remains to be clarified;policy needs to be optimized;the platform is imperfect and so on.To further deepen the reform is the key for youth social organization to participate,which needs developing the organization subj ects,reshaping the trust,building the consensus,adj usting the structure ,perfecting the policy and building the platform so as to build the e-qual cooperation for youth social organization in community participation,as well as to form the new pat-tern of mutual benefits and the shared development.

  6. Network Characterization Service (NCS)

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Guojun [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Yang, George [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Crowley, Brian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Agarwal, Deborah [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2001-06-06

    Distributed applications require information to effectively utilize the network. Some of the information they require is the current and maximum bandwidth, current and minimum latency, bottlenecks, burst frequency, and congestion extent. This type of information allows applications to determine parameters like optimal TCP buffer size. In this paper, we present a cooperative information-gathering tool called the network characterization service (NCS). NCS runs in user space and is used to acquire network information. Its protocol is designed for scalable and distributed deployment, similar to DNS. Its algorithms provide efficient, speedy and accurate detection of bottlenecks, especially dynamic bottlenecks. On current and future networks, dynamic bottlenecks do and will affect network performance dramatically.

  7. Learning to achieve perfect, timesharing : Architectural implications of Hazeltine, Teague, and Ivry

    NARCIS (Netherlands)

    Anderson, John; Taatgen, NA; Byrne, MD

    2005-01-01

    E. Hazeltine, D. Teague, and R. B. Ivry (2002) have presented data that have been interpreted as evidence against a central bottleneck. This article describes simulations of their Experiments I and 4 in the ACT-R cognitive architecture, which does possess a central bottleneck in production execution

  8. Sex determination meltdown upon biological control introduction of the parasitoid Cotesia rubecula?

    NARCIS (Netherlands)

    de Boer, Jetske G.; Kuijper, Bram; Heimpel, George E.; Beukeboom, Leo W.

    2012-01-01

    Natural enemies may go through genetic bottlenecks during the process of biological control introductions. Such bottlenecks are expected to be particularly detrimental in parasitoid Hymenoptera that exhibit complementary sex determination (CSD). CSD is associated with a severe form of inbreeding dep

  9. A Highly Scalable Parallel Boundary Element Method for Capacitance Extraction

    OpenAIRE

    Hsiao, Yu-Chung; Daniel, Luca

    2011-01-01

    Traditional parallel boundary element methods suffer from low parallel efficiency and poor scalability due to the long system solving time bottleneck. In this paper, we demonstrate how to avoid such a bottleneck by using an instantiable basis function approach. In our demonstrated examples, we achieve 90% parallel efficiency and scalability both in shared memory and distributed memory parallel systems.

  10. Stocking impact and temporal stability of genetic composition in a brackish northern pike population ( Esox lucius L.), assessed using microsatellite DNA analysis of historical and contemporary samples

    DEFF Research Database (Denmark)

    Larsen, Peter Foged; Hansen, Michael Møller; Eg Nielsen, Einar;

    2005-01-01

    three populations used for stocking. Despite large numbers of stocked fry, the results from both individual and population level admixture analyses demonstrated extremely poor performance and 250), but there were indications of bottlenecks in all samples and populations. We ascribe this finding to...... historical rather than recent bottlenecks, possibly dating back to founder events associated with postglacial recolonisation....

  11. Development Path for Agricultural Modernization of Shaanxi Province from the Perspective of Technological Progress

    Institute of Scientific and Technical Information of China (English)

    Lufeng; DUAN

    2013-01-01

    The lag in technological innovation is a bottleneck for modern agricultural development,so technological progress is an inevitable path to break this bottleneck. On the basis of introducing theory of technological progress,this study presents 4 paths for promoting agricultural modernization development in line with current situations of agricultural development and technological progress in Shaanxi Province.

  12. Regulation in the media-internet-telecom value web : Introducing the Damian method for systematic analysis of the interdependencies between services, organisations and regulation

    NARCIS (Netherlands)

    Nooren, P.A.; Koers, W.A.; Bangma, M.R.; Berkers, F.T.H.M.; Boertjes, E.M.

    2014-01-01

    The convergence between media, internet and telecoms has brought many new services, devices and distribution models. The availability of multiple routes for delivery of services to end users helps to remove a number of traditional bottlenecks. At the same time, new bottlenecks can appear as the rout

  13. Snapshot of E-Commerce's Opportunities and Threats

    NARCIS (Netherlands)

    Saanen, Y. A.; Verbraeck, Alexander; Sol, H

    1999-01-01

    E-commerce offers opportunities to change the way of doing business. However fully utilizing these opportunities and overcoming the bottlenecks, requires more than just getting online. The currently low Internet trade volumes confirm this. This paper gives a snapshot of opportunities and bottlenecks

  14. Management of Knowledge Representation Standards Activities

    Science.gov (United States)

    Patil, Ramesh S. (Principal Investigator)

    1993-01-01

    This report describes the efforts undertaken over the last two years to identify the issues underlying the current difficulties in sharing and reuse, and a community wide initiative to overcome them. First, we discuss four bottlenecks to sharing and reuse, present a vision of a future in which these bottlenecks have been ameliorated, and describe the efforts of the initiative's four working groups to address these bottlenecks. We then address the supporting technology and infrastructure that is critical to enabling the vision of the future. Finally, we consider topics of longer-range interest by reviewing some of the research issues raised by our vision.

  15. Towards transformational change: UNDP's work in environment and sustainable development 2008-2012

    Energy Technology Data Exchange (ETDEWEB)

    Mordt, Matilde; Hildebrandt, Laura; Iyer, Devika; Fankuchen, Alexander

    2013-03-15

    This report highlights significant advances in sustainable development from almost 60 country reports and underscores the challenges and bottlenecks to moving beyond the economic-led growth strategies of the past 20 years.

  16. Improving traffic flow at a 2-to-1 lane reduction with wirelessly connected, adaptive cruise control vehicles

    CERN Document Server

    Davis, L C

    2015-01-01

    Wirelessly connected vehicles that exchange information about traffic conditions can reduce delays caused by congestion. At a 2-to-1 lane reduction, the improvement in flow past a bottleneck due to traffic with a random mixture of 40% connected vehicles is found to be 52%. Control is based on connected-vehicle-reported velocities near the bottleneck. In response to indications of congestion the connected vehicles, which are also adaptive cruise control vehicles, reduce their speed in slowdown regions. Early lane changes of manually driven vehicles from the terminated lane to the continuous lane are induced by the slowing connected vehicles. Self-organized congestion at the bottleneck is thus delayed or eliminated, depending upon the incoming flow magnitude. For the large majority of vehicles, travel times past the bottleneck are substantially reduced. Control is responsible for delaying the onset of congestion as the incoming flow increases. Adaptive cruise control increases the flow out of the congested stat...

  17. eBank UK : dissemination of research data using EPrints [Open Access to Scientific Data and Publications

    OpenAIRE

    Coles, Simon

    2005-01-01

    Scholarly communications in Chemistry (data, information, workflows and provenance); the data publication bottleneck (e-Science and chemistry); eBank UK (information architecture, data flow and interoperability); challenges for the future (expansion into other disciplines and data formats).

  18. Prognosis renewable energy. 2013 report; Prognose hernieuwbare energie. Rapportage 2013

    Energy Technology Data Exchange (ETDEWEB)

    Neeft, J.; Dijkstra, J.; Van Erp, F.; Leguijt, T.

    2013-10-15

    A prognosis for the estimate share of renewable energy in the upcoming years in the Netherlands, including bottlenecks and risks [Dutch] Een vooruitblik op het geschatte aandeel hernieuwbare energie voor de komende jaren, inclusief knelpunten en risico's.

  19. A methodological approach to BISDN signalling performance

    NARCIS (Netherlands)

    Hou, X.; Kalogeropoulos, N.D.; Lekkou, M.E.; Niemegeers, I.G.; Venieris, I.S.

    1994-01-01

    Sophisticated signalling protocols are required to properly handle the complex multimedia, multiparty services supported by the forthcoming BISDN. The implementation feasibility of these protocols should be evaluated during their design phase, so that possible performance bottlenecks are identified

  20. Applying high resolution mass spectrometry and network analysis to assess exposure to a novel androgen, spironolactone, on metabolic pathways in fish

    Science.gov (United States)

    Although metabolomics can successfully detect effects from overall contaminant exposure, its ability to elucidate specific metabolic pathways impacted by those exposures can be hindered by bottlenecks in metabolite identification. However, improved analytical approaches that com...

  1. Electrically Injected Polariton Lasing from a GaAs-Based Microcavity under Magnetic Field

    KAUST Repository

    Bhattacharya, Pallab

    2012-01-01

    Suppression of relaxation bottleneck and subsequent polariton lasing is observed in a GaAs-based microcavity under the application of a magnetic field. The threshold injection current density is 0.32 A/cm2 at 7 Tesla.

  2. Debt relief and financing climate change action

    Science.gov (United States)

    Fenton, Adrian; Wright, Helena; Afionis, Stavros; Paavola, Jouni; Huq, Saleemul

    2014-08-01

    Slow progress in scaling-up climate finance has emerged as a major bottleneck in international negotiations. Debt relief for climate finance swaps could provide an alternative source for financing mitigation and adaptation action in developing countries.

  3. Bio-economic modelling of arable farming system, comparison of conventional and organic farming systems in the Netherlands

    NARCIS (Netherlands)

    Acs, S.; Berentsen, P.B.M.; Wolf, de M.; Huirne, R.B.M.

    2004-01-01

    Met behulp van twee statische lineaire programmeringsmodellen zijn de technische, economische en milieu resultaten van een gespecialiseerd gangbaar en een gespecialiseerd biologisch landbouwbedrijf vergeleken. Deze modellen zullen als basis dienen voor een dynamisch model waarbij de bottlenecks tijd

  4. Rainwater Basin Seed Availability, depletion, and Waterfowl Response During Spring Migration

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Rainwater Basin RWB is a spring migration bottleneck for millions of migratory waterfowl that stage in Nebraska. Wetlandderived seed resources are believed to...

  5. IDEOM : an Excel interface for analysis of LC-MS-based metabolomics data

    NARCIS (Netherlands)

    Creek, Darren J.; Jankevics, Andris; Burgess, Karl E. V.; Breitling, Rainer; Barrett, Michael P.; Wren, Jonathan

    2012-01-01

    The application of emerging metabolomics technologies to the comprehensive investigation of cellular biochemistry has been limited by bottlenecks in data processing, particularly noise filtering and metabolite identification. IDEOM provides a user-friendly data processing application that automates

  6. Alpha complexes in protein structure prediction

    DEFF Research Database (Denmark)

    Winter, Pawel; Fonseca, Rasmus

    2015-01-01

    Reducing the computational effort and increasing the accuracy of potential energy functions is of utmost importance in modeling biological systems, for instance in protein structure prediction, docking or design. Evaluating interactions between nonbonded atoms is the bottleneck of such computatio...

  7. Automatic Performance Debugging of SPMD-style Parallel Programs

    CERN Document Server

    Liu, Xu; Zhan, Kunlin; Shi, Weisong; Yuan, Lin; Meng, Dan; Wang, Lei

    2011-01-01

    The simple program and multiple data (SPMD) programming model is widely used for both high performance computing and Cloud computing. In this paper, we design and implement an innovative system, AutoAnalyzer, that automates the process of debugging performance problems of SPMD-style parallel programs, including data collection, performance behavior analysis, locating bottlenecks, and uncovering their root causes. AutoAnalyzer is unique in terms of two features: first, without any apriori knowledge, it automatically locates bottlenecks and uncovers their root causes for performance optimization; second, it is lightweight in terms of the size of performance data to be collected and analyzed. Our contributions are three-fold: first, we propose two effective clustering algorithms to investigate the existence of performance bottlenecks that cause process behavior dissimilarity or code region behavior disparity, respectively; meanwhile, we present two searching algorithms to locate bottlenecks; second, on a basis o...

  8. Potential for sustainable energy with biogas from sewage purification

    International Nuclear Information System (INIS)

    Insight is given into the possibility to produce biogas from sewage purification plants in the Netherlands. Attention is paid to the estimated potential of sustainable energy from biogas, the economic effectiveness of several scenarios, the critical success factors and bottlenecks

  9. Biological Effect of Muller's Ratchet: Distant Capsid Site Can Affect Picornavirus Protein Processing▿

    OpenAIRE

    Escarmís, Cristina; Perales, Celia; Domingo, Esteban

    2009-01-01

    Repeated bottleneck passages of RNA viruses result in accumulation of mutations and fitness decrease. Here, we show that clones of foot-and-mouth disease virus (FMDV) subjected to bottleneck passages, in the form of plaque-to-plaque transfers in BHK-21 cells, increased the thermosensitivity of the viral clones. By constructing infectious FMDV clones, we have identified the amino acid substitution M54I in capsid protein VP1 as one of the lesions associated with thermosensitivity. M54I affects ...

  10. Inside the Queue

    OpenAIRE

    Verhoef, Erik T.

    2002-01-01

    This paper develops a continuous-time -continuous-place economic model of road trafficcongestion with a bottleneck, based on car-following theory. The model integrates twoarchetype congestion technologies used in the economics literature: 'static flow congestion',originating in the works of Pigou, and 'dynamic bottleneck congestion', pioneered byVickrey. Because a closed-form analytical solution of the formal model does not exist, itsbehaviour is explored using a simulation model. In a settin...

  11. Gargalos à Expansão da Produção e Comercialização do Algodão Agroecológico. O Caso de uma Associação de Produtores Familiares no Nordeste do Brasil

    OpenAIRE

    Luis Carlos Zucatto; Haroldo de Sá Medeiros; Tania Nunes da Silva; Mariluce Paes de Souza

    2015-01-01

    BOTTLENECKS TO THE EXPANSION OF PRODUCTIONAND COMMERCIALIZATION OF AGRO-ECOLOGICAL COTTON:THE FAMILY FARMERS ASSOCIATION IN NORTHEAST BRAZIL CASEAbstractThis study aims to identify bottlenecks to the expansion of production and commercialization ofagro-ecological cotton produced by Family farmers in the Northeast of Brazil associated to the ADEC(Association for Educational and Cultural Development, Taua – Ceará). In conducting the study weobserved a qualitative approach in collecting data thr...

  12. Insights Into Mitochondrial Genetic and Morphologic Dynamics Gained by Stochastic Simulation

    OpenAIRE

    Rajasimha, Harsha Karur

    2007-01-01

    MtDNA mutations in mammalian cells are implicated in cellular ageing and encephalomyopathies, although mechanisms involved are not completely understood. The mitochondrial genetic bottleneck has puzzled biologists for a long time. Approximate models of genetic bottleneck proposed in the literature do not accurately model underlying biology. Recent studies indicate mitochondrial morphology changes during cellular ageing in culture. In particular, the rates of mitochondrial fission and fusion a...

  13. Assessment of wireless solutions in emerging broadband markets

    OpenAIRE

    Benseny Quintana, Jaume

    2016-01-01

    Although broadband markets have grown steadily since the advent of the mobile Internet, penetration levels for developing countries are far from reaching the ordinary citizen. This thesis analyses three hypotheses as bottlenecks to the growth of emerging mobile broadband markets: (i) the low competence of users, (ii) the low quality of service, (iii) the high access price and, based on the results, alternative wireless solutions are studied to accelerate the Internet diffusion. Bottleneck...

  14. The Balanced Cube: A Concurrent Data Structure

    OpenAIRE

    Dally, William J.; Seitz, Charles L.

    1985-01-01

    This paper describee the balanced cube, a new data structure for implementing ordered seta. Conventional dats structures such as heaps, balanced trees and B-trees have root bottlenecks which limit their potential concurrency and make them unable to take advantage of the computing potential of concurrent machines. The balanced cube achieves greater concurrency by eliminating the root bottleneck; an operation in the balanced cube can be initiated from any node. The throughput of ...

  15. Metabolic pathway engineering of the toluene degradation pathway

    OpenAIRE

    Regan, L.

    1995-01-01

    This thesis addresses the problem of how to examine a metabolic pathway and identify what are the key elements, specifically with respect to rate-limitation. The aim is to be able to analyze a pathway, identify the bottlenecks and implement genetic modifications to remove these bottlenecks. This is done by defining the system of interest and developing a predictive model using kinetic data. The model predictions can then be verified using fermentation data and genetic technique...

  16. Socio-demographic influences on language structure and change: Not all learners are the same.

    Science.gov (United States)

    Bergmann, Till; Dale, Rick; Lupyan, Gary

    2016-01-01

    The Now-or-Never bottleneck has important consequence for understanding why languages have the structures they do. However, not addressed by C&C is that the bottleneck may interact with who is doing the learning: While some languages are mostly learned by infants, others have a large share of adult learners. We argue that such socio-demographic differences extend and qualify C&C's thesis. PMID:27562311

  17. HPC application address stream compression, replay and scaling

    OpenAIRE

    Olschanowsky, Catherine Rose Mills

    2011-01-01

    As the capabilities of high performance computing (HPC) resources have grown over the last decades, a performance gap has developed and expanded between the processor and memory. Processor speeds have improved according to Moore's law, while memory bandwidth has lagged behind. The performance bottleneck created by this gap, termed the "Von Neuman bottleneck," has been the driving force behind the development of modern memory subsystems. Many advances have been made aimed at hiding this memory...

  18. Circuit and interconnect design for high bit-rate applications

    OpenAIRE

    Veenstra, H.

    2006-01-01

    This thesis presents circuit and interconnect design techniques and design flows that address the most difficult and ill-defined aspects of the design of ICs for high bit-rate applications. Bottlenecks in interconnect design, circuit design and on-chip signal distribution for high bit-rate applications are analysed, and solutions that circumvent these bottlenecks are presented. The methodologies presented indicate whether certain target bit-rates and operating frequencies can be realised in t...

  19. Gas at work. Vision on decentralized gas appliances in the built environment

    International Nuclear Information System (INIS)

    Various platforms operate within the SenterNovem programme Creative Energy. This report is the first version of the vision document of the working group Decentralized gas appliances of the Platform New Gas, in which the following aspects of the various promising innovative gas appliances are indicated: the development stage, the intended energy saving, the CO2 reduction, the bottlenecks for large scale market introduction and the solutions for these bottlenecks. [mk

  20. Maximizing throughput by evaluating critical utilization paths

    OpenAIRE

    Weeda, P.J.

    1991-01-01

    Recently the relationship between batch structure, bottleneck machine and maximum throughput has been explored for serial, convergent and divergent process configurations consisting of two machines and three processes. In three of the seven possible configurations a multiple batch structure maximizes time-constrained throughput. The principle of scheduling a bottleneck. Critical utilization paths provide a convenient vehicle to evaluate multiple batch structures by means of integer programmin...

  1. Increasing granular flow rate with obstructions

    OpenAIRE

    Alan Murray; Fernando Alonso-Marroquin

    2016-01-01

    We describe a simple experiment involving spheres rolling down an inclined plane towards a bottleneck and through a gap. Results of the experiment indicate that flow rate can be increased by placing an obstruction at optimal positions near the bottleneck. We use the experiment to develop a computer simulation using the PhysX physics engine. Simulations confirm the experimental results and we state several considerations necessary to obtain a model that agrees well with experiment. We demonstr...

  2. Sex determination meltdown upon biological control introduction of the parasitoid Cotesia rubecula?

    OpenAIRE

    Boer; Kuijper, B.; Heimpel, G.E.; Beukeboom, L. W.

    2012-01-01

    Natural enemies may go through genetic bottlenecks during the process of biological control introductions. Such bottlenecks are expected to be particularly detrimental in parasitoid Hymenoptera that exhibit complementary sex determination (CSD). CSD is associated with a severe form of inbreeding depression because homozygosity at one or multiple sex loci leads to the production of diploid males that are typically unviable or sterile. We observed that diploid males occur at a relatively high r...

  3. The Study on the Promotion of Small and Medium-Sized Enterprises Development——Take Nanning for example%促进中小企业发展初探——以南宁市为例

    Institute of Scientific and Technical Information of China (English)

    龚维玲

    2009-01-01

    With developing and improving the socialist market economic deeply, small and medium-sized enterprises in our country will strengthen more and more powerful, and their position and role in economic and social development will be increasingly important, small and medium-sized enterprises in Nanning exist talent development bottleneck, financing bottleneck, manage bottleneck, credit bottleneck, the bottleneck of innovation, strategic bottleneck and other issues, so they should do a good job in system innovation, product innovation, technological innovation, environmental innovation, and so on.%随着社会主义市场经济的深入发展和不断完善,我国中小企业将越来越发展壮大,在经济与社会发展中的地位和作用也会越来越重要.南宁市中小企业发展存在人才瓶颈、融资瓶颈、管理瓶颈、信用瓶颈、创新瓶颈、战略瓶颈等问题,因此应抓好制度创新、产品创新、技术创新、环境创新等.

  4. Concordance of nuclear and mitochondrial DNA markers in detecting a founder event in Lake Clark sockeye salmon

    Science.gov (United States)

    Ramstad, Kristina M.; Woody, Carol Ann; Habicht, Chris; Sage, G. Kevin; Seeb, James E.; Allendorf, Fred W.

    2007-01-01

    Genetic bottleneck effects can reduce genetic variation, persistence probability, and evolutionary potential of populations. Previous microsatellite analysis suggested a bottleneck associated with a common founding of sock-eye salmon Oncorhynchus nerka populations of Lake Clark, Alaska, about 100 to 400 generations ago. The common foundingevent occurred after the last glacial recession and resulted in reduced allelic diversity and strong divergence of Lake Clarksockeye salmon relative to neighboring Six Mile Lake and LakeIliamna populations. Here we used two additional genetic marker types (allozymes and mtDNA) to examine these patterns further. Allozyme and mtDNA results were congruent with the microsatellite data in suggesting a common founder event in LakeClark sockeye salmon and confirmed the divergence of Lake Clarkpopulations from neighboring Six Mile Lake and Lake Iliamna populations. The use of multiple marker types provided better understanding of the bottleneck in Lake Clark. For example, the Sucker Bay Lake population had an exceptionally severe reduction in allelic diversity at microsatellite loci, but not at mtDNA. This suggests that the reduced microsatellite variation in Sucker Bay Lake fish is due to consistently smaller effective population size than other Lake Clark populations, rather than a more acute or additional bottleneck since founding. Caution is urged in using reduced heterozygosity as a measure of genetic bottleneck effects because stochastic variance among loci resulted in an overall increase in allozyme heterozygosity within bottlenecked Lake Clark populations. However, heterozygosity excess, which assesses heterozygosity relative to allelic variation, detected genetic bottleneck effects in both allozyme and microsatellite loci. 

  5. Handling transmission limitations in the central power network; Haandtering av overfoeringsbegrensninger

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-01

    From 1996, the Norwegian and Swedish power markets were joined and a common power exchange was established. The two countries deal differently with bottlenecks (transmission obstruction) in their central networks. This report compares methods for dealing with such bottlenecks and looks at the alternatives. It emphasises the efficiency of pricing and incentives and the possibility of exercising market power under the different methods. Norway uses a method of price regions, or bottleneck tax. Prices are determined for the various price regions so as to keep the power flow below specified bounds. A surplus region is assigned a lower price than a deficit region and the bottleneck tax is the difference in price between two such price regions. The Swedish system is based on a counter purchase concept. In his offer to the spotmarket, the supplier has bound himself to provide a certain amount to the current system price regardless of network limitations. Up-regulation means that he produces more than this amount. Down-regulation means that he is paid for supplying less than he had offered to the current system price. In up- or down-regulation, compensation is given as the difference between the system price and the price on the counter purchase market. The main conclusions are: (1) Counter purchase is unsuitable as the main strategy for Norway. (2) Counter purchase may be suitable with short-lived and unpredicted bottlenecks; price regions may be suitable for long-lasting and predicted bottlenecks. Time is a central factor. (3) Present-day models for bottleneck management in Norway and Sweden do not give the optimum short-term load distribution on the network. In general, the current Norwegian system works fairly well, although it might be worthwhile to consider a system that approaches node pricing. 3 refs., 34 figs., 3 tabs.

  6. Characterizing corridor-level travel time distributions based on stochastic flows and segment capacities

    Directory of Open Access Journals (Sweden)

    Hao Lei

    2015-12-01

    Full Text Available Trip travel time reliability is an important measure of transportation system performance and a key factor affecting travelers’ choices. This paper explores a method for estimating travel time distributions for corridors that contain multiple bottlenecks. A set of analytical equations are used to calculate the number of queued vehicles ahead of a probe vehicle and further capture many important factors affecting travel times: the prevailing congestion level, queue discharge rates at the bottlenecks, and flow rates associated with merges and diverges. Based on multiple random scenarios and a vector of arrival times, the lane-by-lane delay at each bottleneck along the corridor is recursively estimated to produce a route-level travel time distribution. The model incorporates stochastic variations of bottleneck capacity and demand and explains the travel time correlations between sequential links. Its data needs are the entering and exiting flow rates and a sense of the lane-by-lane distribution of traffic at each bottleneck. A detailed vehicle trajectory data-set from the Next Generation SIMulation (NGSIM project has been used to verify that the estimated distributions are valid, and the sources of estimation error are examined.

  7. Genome-wide patterns of nucleotide polymorphism in domesticated rice.

    Directory of Open Access Journals (Sweden)

    Ana L Caicedo

    2007-09-01

    Full Text Available Domesticated Asian rice (Oryza sativa is one of the oldest domesticated crop species in the world, having fed more people than any other plant in human history. We report the patterns of DNA sequence variation in rice and its wild ancestor, O. rufipogon, across 111 randomly chosen gene fragments, and use these to infer the evolutionary dynamics that led to the origins of rice. There is a genome-wide excess of high-frequency derived single nucleotide polymorphisms (SNPs in O. sativa varieties, a pattern that has not been reported for other crop species. We developed several alternative models to explain contemporary patterns of polymorphisms in rice, including a (i selectively neutral population bottleneck model, (ii bottleneck plus migration model, (iii multiple selective sweeps model, and (iv bottleneck plus selective sweeps model. We find that a simple bottleneck model, which has been the dominant demographic model for domesticated species, cannot explain the derived nucleotide polymorphism site frequency spectrum in rice. Instead, a bottleneck model that incorporates selective sweeps, or a more complex demographic model that includes subdivision and gene flow, are more plausible explanations for patterns of variation in domesticated rice varieties. If selective sweeps are indeed the explanation for the observed nucleotide data of domesticated rice, it suggests that strong selection can leave its imprint on genome-wide polymorphism patterns, contrary to expectations that selection results only in a local signature of variation.

  8. Genome-Wide Loss of Diversity in the Critically Endangered Hawaiian Monk Seal

    Directory of Open Access Journals (Sweden)

    Jennifer K. Schultz

    2010-05-01

    Full Text Available Threatened species often exhibit low genetic diversity as a result of selective sweeps, historical bottlenecks, or persistent small population size. Whereas selective sweeps create localized reduction of variation at a chromosome, population bottlenecks result in the loss of rare alleles throughout the genome. Heterozygosity is lost more slowly and is severely impacted only when populations are small for an extended period of time. We test the hypotheses of selective sweep, historical bottleneck and persistently small population size to explain extremely low genetic diversity in the critically endangered Hawaiian monk seal (Monachus schauinslandi. Of 163 microsatellite loci isolated from the species’ genome, only 17 are polymorphic. Mapping 98 monomorphic and 12 polymorphic loci to 35 chromosomes throughout the dog genome, we reject the selective sweep hypothesis. Genotyping 2,423 Hawaiian monk seals at the 17 polymorphic loci plus a locus previously isolated from another pinniped species, we find evidence for a recent bottleneck (P = 0.04. This is consistent with historical records describing intense hunting in the 19th century; however, the bottleneck was not of sufficient severity and duration to explain the genome-wide depletion of genetic diversity (HO = 0.05; A = 1.1. Long-term population size restriction is a more likely explanation. Though at least two of the polymorphic loci appear to be candidates for selection, the low genetic diversity of the species may further threaten chances for survival of this critically endangered species in a changing world.

  9. Dual-task interference with equal task emphasis: graded capacity sharing or central postponement?

    Science.gov (United States)

    Ruthruff, Eric; Pashler, Harold E.; Hazeltine, Eliot

    2003-01-01

    Most studies using the psychological refractory period (PRP) design suggest that dual-task performance is limited by a central bottleneck. Because subjects are usually told to emphasize Task 1, however, the bottleneck might reflect a strategic choice rather than a structural limitation. To evaluate the possibility that central operations can proceed in parallel, albeit with capacity limitations, we conducted two dual-task experiments with equal task emphasis. In both experiments, subjects tended to either group responses together or respond to one task well before the other. In addition, stimulus-response compatibility effects were roughly constant across stimulus onset asynchronies (SOAs). At the short SOA, compatibility effects also carried over onto response times for the other task. This pattern of results is difficult to reconcile with the possibility that subjects share capacity roughly equally between simultaneous central operations. However, this pattern is consistent with the existence of a structural central bottleneck.

  10. Automatic Performance Debugging of SPMD Parallel Programs

    CERN Document Server

    Liu, Xu; Zhan, Jianfeng; Tu, Bibo; Meng, Dan

    2010-01-01

    Automatic performance debugging of parallel applications usually involves two steps: automatic detection of performance bottlenecks and uncovering their root causes for performance optimization. Previous work fails to resolve this challenging issue in several ways: first, several previous efforts automate analysis processes, but present the results in a confined way that only identifies performance problems with apriori knowledge; second, several tools take exploratory or confirmatory data analysis to automatically discover relevant performance data relationships. However, these efforts do not focus on locating performance bottlenecks or uncovering their root causes. In this paper, we design and implement an innovative system, AutoAnalyzer, to automatically debug the performance problems of single program multi-data (SPMD) parallel programs. Our system is unique in terms of two dimensions: first, without any apriori knowledge, we automatically locate bottlenecks and uncover their root causes for performance o...

  11. Basic model for traffic interweave

    Science.gov (United States)

    Huang, Ding-wei

    2015-09-01

    We propose a three-parameter traffic model. The system consists of a loop with two junctions. The three parameters control the inflow, the outflow (from the junctions,) and the interweave (in the loop.) The dynamics is deterministic. The boundary conditions are stochastic. We present preliminary results for a complete phase diagram and all possible phase transitions. We observe four distinct traffic phases: free flow, congestion, bottleneck, and gridlock. The proposed model is able to present economically a clear perspective to these four different phases. Free flow and congestion are caused by the traffic conditions in the junctions. Both bottleneck and gridlock are caused by the traffic interweave in the loop. Instead of directly related to conventional congestion, gridlock can be taken as an extreme limit of bottleneck. This model can be useful to clarify the characteristics of traffic phases. This model can also be extended for practical applications.

  12. Parallel Algormiivls For Optical Digital Computers

    Science.gov (United States)

    Huang, Alan

    1983-04-01

    Conventional computers suffer from several communication bottlenecks which fundamentally limit their performance. These bottlenecks are characterized by an address-dependent sequential transfer of information which arises from the need to time-multiplex information over a limited number of interconnections. An optical digital computer based on a classical finite state machine can be shown to be free of these bottlenecks. Such a processor would be unique since it would be capable of modifying its entire state space each cycle while conventional computers can only alter a few bits. New algorithms are needed to manage and use this capability. A technique based on recognizing a particular symbol in parallel and replacing it in parallel with another symbol is suggested. Examples using this parallel symbolic substitution to perform binary addition and binary incrementation are presented. Applications involving Boolean logic, functional programming languages, production rule driven artificial intelligence, and molecular chemistry are also discussed.

  13. Improving traffic flow at a 2-to-1 lane reduction with wirelessly connected, adaptive cruise control vehicles

    Science.gov (United States)

    Davis, L. C.

    2016-06-01

    Wirelessly connected vehicles that exchange information about traffic conditions can reduce delays caused by congestion. At a 2-to-1 lane reduction, the improvement in flow past a bottleneck due to traffic with a random mixture of 40% connected vehicles is found to be 52%. Control is based on connected-vehicle-reported velocities near the bottleneck. In response to indications of congestion the connected vehicles, which are also adaptive cruise control vehicles, reduce their speed in slowdown regions. Early lane changes of manually driven vehicles from the terminated lane to the continuous lane are induced by the slowing connected vehicles. Self-organized congestion at the bottleneck is thus delayed or eliminated, depending upon the incoming flow magnitude. For the large majority of vehicles, travel times past the bottleneck are substantially reduced. Control is responsible for delaying the onset of congestion as the incoming flow increases. Adaptive cruise control increases the flow out of the congested state at the bottleneck. The nature of the congested state, when it occurs, appears to be similar under a variety of conditions. Typically 80-100 vehicles are approximately equally distributed between the lanes in the 500 m region prior to the end of the terminated lane. Without the adaptive cruise control capability, connected vehicles can delay the onset of congestion but do not increase the asymptotic flow past the bottleneck. Calculations are done using the Kerner-Klenov three-phase theory, stochastic discrete-time model for manual vehicles. The dynamics of the connected vehicles is given by a conventional adaptive cruise control algorithm plus commanded deceleration. Because time in the model for manual vehicles is discrete (one-second intervals), it is assumed that the acceleration of any vehicle immediately in front of a connected vehicle is constant during the time interval, thereby preserving the computational simplicity and speed of a discrete-time model.

  14. CSCW Challenges in Large-Scale Technical Projects - a case study

    DEFF Research Database (Denmark)

    Grønbæk, Kaj; Kyng, Morten; Mogensen, Preben Holst

    1992-01-01

    This paper investigates CSCW aspects of large-scale technical projects based on a case study of a specific Danish engineering company and uncovers s challenges to CSCW applications in this setting. The company is responsible for management and supervision of one of the worlds largest tunnel....... The initial qualitative analysis identified a number of bottlenecks in daily work, where support for cooperation is needed. Examples of bottlenecks are: sharing materials, issuing tasks, and keeping track of task status. Grounded in the analysis, cooperative design workshops based on scenarios of...

  15. Experimental Peptide Identification Repository (EPIR): an integrated peptide-centric platform for validation and mining of tandem mass spectrometry data

    DEFF Research Database (Denmark)

    Kristensen, Dan Bach; Brønd, Jan Christian; Nielsen, Peter Aagaard;

    2004-01-01

    LC MS/MS has become an established technology in proteomic studies, and with the maturation of the technology the bottleneck has shifted from data generation to data validation and mining. To address this bottleneck we developed Experimental Peptide Identification Repository (EPIR), which...... information. In the present study, the utility of EPIR and associated software tools is demonstrated on LC MS/MS data derived from a set of model proteins and complex protein mixtures derived from MCF-7 breast cancer cells. Emphasis is placed on the key strengths of EPIR, including the ability to validate...

  16. iPhone Applications Tune-Up

    CERN Document Server

    Moses, Loyal

    2011-01-01

    Written to be read straight through as well as to be used as a technical reference, each chapter of this book focuses on an individual aspect of application performance and how it relates to the overall development and tune-up process. The reader will be introduced to the fundamentals of iOS performance bottlenecks and how poor application performance can and does affect a user's experience, adoption, and ultimately success This book is for iOS application developers who are interested in resolving application performance bottlenecks in both new and existing Xcode projects. Readers should be f

  17. Wyner-Ziv Video Coding using Hadamard Transform and Deep Learning

    Directory of Open Access Journals (Sweden)

    Jean-Paul Kouma

    2016-07-01

    Full Text Available Predictive schemes are current standards of video coding. Unfortunately they do not apply well for lightweight devices such as mobile phones. The high encoding complexity is the bottleneck of the Quality of Experience (QoE of a video conversation between mobile phones. A considerable amount of research has been conducted towards tackling that bottleneck. Most of the schemes use the so-called Wyner-Ziv Video Coding Paradigm, with results still not comparable to those of predictive coding. This paper shows a novel approach for Wyner-Ziv video compression. It is based on the Reinforcement Learning and Hadamard Transform. Our Scheme shows very promising results.

  18. Matching in Gabriel Graphs

    OpenAIRE

    Biniaz, Ahmad; Maheshwari, Anil; Smid, Michiel

    2014-01-01

    Given a set $P$ of $n$ points in the plane, the order-$k$ Gabriel graph on $P$, denoted by $k$-$GG$, has an edge between two points $p$ and $q$ if and only if the closed disk with diameter $pq$ contains at most $k$ points of $P$, excluding $p$ and $q$. We study matching problems in $k$-$GG$ graphs. We show that a Euclidean bottleneck perfect matching of $P$ is contained in $10$-$GG$, but $8$-$GG$ may not have any Euclidean bottleneck perfect matching. In addition we show that $0$-$GG$ has a m...

  19. Prediction of anisotropic transport in Nafion containing catalyst layers

    Energy Technology Data Exchange (ETDEWEB)

    Dorenbos, G.; Pomogaev, V.A.; Takigawa, M. [Knowledgenet Co., Lofty Chuo Bldg. (9F), 1-17-24, Shinkawa, Chuo-ku, Tokyo 104-0033 (Japan); Toyota Motor Co., Future Project Division, 1200 Mishuku, Susono, Shizuoka 410-1193 (Japan); Morohoshi, K. [Toyota Motor Co., Future Project Division, 1200 Mishuku, Susono, Shizuoka 410-1193 (Japan)

    2010-01-15

    Using dissipative particle dynamics we model phase separation within Nafion electrolytes of thickness between 5 and 10 nm containing 20 volume percent water, sandwiched between a carbon catalyst support (CCS) layer and air. The diffusion pathway for protons and water is probed by Monte Carlo trajectory calculations. While varying the interactions between CCS and water, diffusion parallel to the CCS is predicted to be highest and perpendicular diffusion to be lowest for a hydrophilic CCS. This is explained by variations in water density profiles along the perpendicular direction, which act as bottlenecks for diffusion. Increasing the hydrophobic character of the CCS lifts up these bottlenecks. (author)

  20. Performance Analysis of TCP-Reno and TCP-Sack in the Case of a Single Source

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This work explores the behavior of both TCP-Reno and TCP-Sack under a simple scenario, where a single TCP source transmits the packets continuously over a single bottleneck node characterized by its queue size, bandwidth and propagation delay. The analysis allows to derive the performance of TCP, the utilization tends to 75% of the bottleneck throughput when the bandwidth × propagation delay pipe becomes very large, while it tends to 100% when the queuing delays are predominant because the queue is never empty. In the transient analysis we show how the initial phase of the session can degrade the performances. These results are proved through simulation.

  1. Improvability of assembly systems II: Improvability indicators and case study

    Directory of Open Access Journals (Sweden)

    S.-Y. Chiang

    2000-01-01

    Full Text Available Based on the performance analysis technique developed in Part I, this paper presents improvability indicators for assembly lines with unreliable machines. In particular, it shows that assembly lines are unimprovable with respect to workforce re-distribution if each buffer is, on the average, close to being half full. These lines are unimprovable with respect to buffer capacity re-distribution if each machine is starved and blocked with almost equal frequency. In addition, the paper provides indicators for identification of bottleneck machines and bottleneck buffers. Finally, the paper reports on an application of these improvability indicators in a case study at an automotive components plant.

  2. DistMap: A Toolkit for Distributed Short Read Mapping on a Hadoop Cluster

    OpenAIRE

    Ram Vinay Pandey; Christian Schlötterer

    2013-01-01

    With the rapid and steady increase of next generation sequencing data output, the mapping of short reads has become a major data analysis bottleneck. On a single computer, it can take several days to map the vast quantity of reads produced from a single Illumina HiSeq lane. In an attempt to ameliorate this bottleneck we present a new tool, DistMap - a modular, scalable and integrated workflow to map reads in the Hadoop distributed computing framework. DistMap is easy to use, currently support...

  3. On the road for a full-grown green gas market. State-of-the-art and points of action

    International Nuclear Information System (INIS)

    Various platforms operate within the SenterNovem programme Creative Energy. In a previous document an outline is given of the vision of the working group Decentralized gas appliances of the Platform New Gas, in which the following aspects of the various promising innovative gas appliances are indicated: the development stage, the intended energy saving, the CO2 reduction, the bottlenecks for large scale market introduction and the solutions for these bottlenecks. In this report an overview is given of what has been realized so far, new developments with regard to green gas and the further ambitions of the working group. [mk].

  4. Load test for the database system of SACLA

    International Nuclear Information System (INIS)

    We performed load test on the database system of MADOCA for SACLA. The database system was consisted of many components, such as server computers, storage system, network, client workstations. Each component was selected to meet the requirements from SACLA operation. However the system has not tested as one system. The actual servers were used at the load test to ensure the system performance. The bottle-neck of the system was also investigated. The resolute shows the system has appropriate ability and the memory of primary database server was the bottle-neck of the system. (author)

  5. Implementing controlled-unitary operations over the butterfly network

    Energy Technology Data Exchange (ETDEWEB)

    Soeda, Akihito; Kinjo, Yoshiyuki; Turner, Peter S. [Department of Physics, Graduate School of Science, The University of Tokyo, Tokyo (Japan); Murao, Mio [Department of Physics, Graduate School of Science, The University of Tokyo, Tokyo, Japan and NanoQuine, The University of Tokyo, Tokyo (Japan)

    2014-12-04

    We introduce a multiparty quantum computation task over a network in a situation where the capacities of both the quantum and classical communication channels of the network are limited and a bottleneck occurs. Using a resource setting introduced by Hayashi [1], we present an efficient protocol for performing controlled-unitary operations between two input nodes and two output nodes over the butterfly network, one of the most fundamental networks exhibiting the bottleneck problem. This result opens the possibility of developing a theory of quantum network coding for multiparty quantum computation, whereas the conventional network coding only treats multiparty quantum communication.

  6. Reproductive dominance of pasture trees in a fragmented tropical forest mosaic

    Science.gov (United States)

    Aldrich; Hamrick

    1998-07-01

    Tropical forest fragmentation threatens biodiversity, yet basic information on population responses for major groups such as plants is lacking. Hypervariable genetic markers were used to reconstruct a population-level pedigree in fragmented tropical forest for the tree Symphonia globulifera. Though seedlings occurred only in remnant forest, the pedigree showed that most seedlings had been produced by sequentially fewer adults in pasture, creating a genetic bottleneck. The pedigree also implicated shifts in the foraging of animals that disperse pollen and seed in a secondary constriction of the bottleneck. These results suggest that tropical conservation strategies should anticipate complex, cryptic responses to fragmentation. PMID:9651242

  7. pXCube云模型的任务划分技术(英文)

    Institute of Scientific and Technical Information of China (English)

    赵亚伟

    2011-01-01

    Query efficiency is bottleneck of XML data cube aggregate query. pXCube is a kind of XML data cube model based on path calculation. Join operations are avoided in this model, but the query efficiency of fact cell is become a new bottleneck. This paper focuses on parallel technology of cloud computing to improve query efficiency of pXCube. Mixed partitioning strategy for fact and dimensions is applied in pXCube cloud model, and the same partitioned vector is adopted. Query parallel algorithm of pXCube cloud ...

  8. Massive Parallelization of Multibody System Simulation

    Directory of Open Access Journals (Sweden)

    Michael Valášek

    2012-01-01

    Full Text Available This paper deals with the decrease in CPU time necessary for simulating multibody systems by massive parallelization. The direct dynamics of multibody systems has to be solved by a system of linear algebraic equations. This is a bottleneck for the efficient usage of multiple processors. Simultaneous solution of this task means that the excitation is immediately spread into all components of the multibody system. The bottleneck can be avoided by introducing additional dynamics, and this leads to the possibility of massive parallelization. Two approaches are described. One is a heterogeneousmultiscale method, and the other involves solving a system of linear algebraic equations by artificial dynamics.

  9. Quasi-Rents and Pricing Gas in Mexico

    OpenAIRE

    Juan Rosellon; Dagobert L. Brito

    2008-01-01

    In 1997, the Comisión Reguladora de Energía of Mexico implemented a netback rule for linking the Mexican natural gas price to the Texas price. At the time, the Texas price reflected a reasonably competitive market. Since that time, there have been dramatic increases in the demand for natural gas and there are various bottlenecks in the supply of natural gas. As a result, the price of natural gas in Texas now reflects the quasi-rents created by these bottlenecks. This paper addresses the optim...

  10. Implementing controlled-unitary operations over the butterfly network

    International Nuclear Information System (INIS)

    We introduce a multiparty quantum computation task over a network in a situation where the capacities of both the quantum and classical communication channels of the network are limited and a bottleneck occurs. Using a resource setting introduced by Hayashi [1], we present an efficient protocol for performing controlled-unitary operations between two input nodes and two output nodes over the butterfly network, one of the most fundamental networks exhibiting the bottleneck problem. This result opens the possibility of developing a theory of quantum network coding for multiparty quantum computation, whereas the conventional network coding only treats multiparty quantum communication

  11. Beam injection into RHIC

    International Nuclear Information System (INIS)

    During the RHIC sextant test in January 1997 beam was injected into a sixth of one of the rings for the first time. The authors describe the injection zone and its bottlenecks. They report on the commissioning of the injection system, on beam based measurements of the kickers and the application program to steer the beam

  12. Increasing mobile radiography productivity.

    Science.gov (United States)

    Wong, Edward; Lung, Ngan Tsz; Ng, Kris; Jeor, Patrick

    2013-01-01

    Mobile radiography using computed radiography (CR) cassettes is a common equipment combination with a workflow bottleneck limited by location of CR readers. Advent of direct digital radiography (DDR) mobile x-ray machines removes this limitation by immediate image review and quality control. Through the use of key performance indicators (KPIs), the increase in efficiency can be quantified. PMID:23986937

  13. Large-Scale Transportation Network Congestion Evolution Prediction Using Deep Learning Theory

    OpenAIRE

    Ma, Xiaolei; Yu, Haiyang; Wang, YunPeng; Wang, Yinhai

    2015-01-01

    Understanding how congestion at one location can cause ripples throughout large-scale transportation network is vital for transportation researchers and practitioners to pinpoint traffic bottlenecks for congestion mitigation. Traditional studies rely on either mathematical equations or simulation techniques to model traffic congestion dynamics. However, most of the approaches have limitations, largely due to unrealistic assumptions and cumbersome parameter calibration process. With the develo...

  14. Capture technologies: Improvements and promising developments

    NARCIS (Netherlands)

    Blomen, E.; Hendriks, C.; Neele, F.

    2009-01-01

    In this status report we want to provide a comprehensive overview of the current status and promising technologies of CO2 capture by means of a literature review, in-house knowledge and interviews. We describe the technology, bottlenecks towards implementation and potential use. The results will be

  15. Sanmenxia strives to create aluminum industrial base

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>Contradiction between rich alumina resource and relatively weak electrolytic aluminum production capacity is the "bottleneck" inhibiting development of aluminum industry in San-menxia. During the period of "11th Five-Year Development", Sanmenxia will relay on its

  16. Co-infection dynamics of a major food-borne zoonotic pathogen in chicken

    DEFF Research Database (Denmark)

    Skanseng, Beate; Trosvik, Pal; Zimonja, Monika;

    2007-01-01

    A major bottleneck in understanding zoonotic pathogens has been the analysis of pathogen co-infection dynamics. We have addressed this challenge using a novel direct sequencing approach for pathogen quantification in mixed infections. The major zoonotic food-borne pathogen Campylobacter jejuni...

  17. Phantom jam avoidance through in-car speed advice

    NARCIS (Netherlands)

    Suijs, L.C.W.; Wismans, L.J.J.; Krol, L.; Berkum, van E.C.

    2015-01-01

    The existence of phantom jams can be explained following the definition of Kerner & Konhäuser (1993) who state that a phantom jam occurs without the existence of a physical bottleneck and is caused by the imperfect driving style of road users under metastable traffic conditions. In order to prevent

  18. Microfluidic approaches to rapid and efficient aptamer selection

    OpenAIRE

    Lin, Hui; Zhang, Weiting; Jia, Shasha; Guan, Zhichao; Yang, Chaoyong James; Zhu, Zhi

    2014-01-01

    With their advantages as molecular recognition elements, aptamers have been extensively studied and used for bioanalytical and biomedical applications. However, the process of enrichment and screening of aptamers remains a bottleneck for aptamer development. Recently, microfluidic methods have been increasingly used for rapid and efficient aptamer selection, showing their remarkable advantages over conventional methods. This review briefly introduces aptamers and their advantages. The convent...

  19. Decoding the Disciplines: An Approach to Scientific Thinking

    Science.gov (United States)

    Pinnow, Eleni

    2016-01-01

    The Decoding the Disciplines methodology aims to teach students to think like experts in discipline-specific tasks. The central aspect of the methodology is to identify a bottleneck in the course content: a particular topic that a substantial number of students struggle to master. The current study compared the efficacy of standard lecture and…

  20. Dynamic Process Planning: A Hybrid Modeling Approach for Real Time Production Scheduling

    OpenAIRE

    Butz, Florian

    2014-01-01

    Background Developments in the manufacturing environment such as shifting markets, emerging technologies and increasing competition require fundamental changes. One aspect is the integration of the activities process planning and process scheduling with the objective to balance resource loading, avoid bottlenecks and lower resource utilization. Method One approach to integrate process planning and scheduling is computer simulation. A manufacturing process of Supreme Precision Manufacturin...

  1. Temporal genetic variation as revealed by a microsatellite analysis of European sardine ( Sardina pilchardus) archived samples

    DEFF Research Database (Denmark)

    Ruggeri, Paolo; Splendiani, Andrea; Bonanomi, Sara;

    2012-01-01

    ) that explain the genetic diversity variation, while the same parameters turned out to be more stable in the southern samples. In addition, we detected the presence of a genetic bottleneck and low effective population size ( Ne) values in several northern samples. Even if the northern and southern...

  2. Mobility2.0: co-operative ITS systems for enhanced electric vehicle mobility

    NARCIS (Netherlands)

    Heijenk, G.; Dimitrova, D.C.; Brogle, M.; Braun, T.; Heijenk, G.J.

    2013-01-01

    Mobility2.0 will develop and test an in-vehicle commuting assistant for FEV mobility, resulting in more reliable and energy-efficient electro-mobility. In order to achieve a maximum impact, Mobility2.0 takes an integrated approach of ad- dressing the main bottlenecks of urban FEV mobility: range anx

  3. Gargalos à Expansão da Produção e Comercialização do Algodão Agroecológico. O Caso de uma Associação de Produtores Familiares no Nordeste do Brasil

    Directory of Open Access Journals (Sweden)

    Luis Carlos Zucatto

    2015-01-01

    Full Text Available BOTTLENECKS TO THE EXPANSION OF PRODUCTIONAND COMMERCIALIZATION OF AGRO-ECOLOGICAL COTTON:THE FAMILY FARMERS ASSOCIATION IN NORTHEAST BRAZIL CASEAbstractThis study aims to identify bottlenecks to the expansion of production and commercialization ofagro-ecological cotton produced by Family farmers in the Northeast of Brazil associated to the ADEC(Association for Educational and Cultural Development, Taua – Ceará. In conducting the study weobserved a qualitative approach in collecting data through interviews and the Web Pages of organiza-tions involved in this activity. As main results, the study suggests that buyers of Adec agroecologicalcotton are companies that make up the Justa Trama Network and Veja (French company that usesthe product for the production of shoes and clothing with fair trade appeals. There are evidencesthat the scale would constitute a relevant bottleneck for the expansion of production and marketingof this product. The production regularity, in the Adec, is strongly influenced by farmers turnover inagroecological cotton production, as well as climate issues. Already, the lack of formation for floatingcapital would be a major bottleneck for production financing. The price at the time of the data collection,was R$ 25.00 per arroba and watches since 2006. The main contribution of the study highlights theStrategy for Agroecology and Market Group, which is articulated as an innovative element in relationto the form of organization of agroecological cotton production and pricing for the same.

  4. Mainly talks about the traffic jams and management countermeasures

    OpenAIRE

    Zhu Kai

    2015-01-01

    With the economic development of China's large and medium-sized cities and city scale expands unceasingly, city traffic congestion problem is also growing, has become a bottleneck hindering the development of the city further. At present, governance urban traffic problem is the first strategic task of traffic congestion. Congestion, maximizing efficiency, convenient travel is to be solved.

  5. Tumor Microenvironment: A New Treatment Target for Cancer

    OpenAIRE

    Ming-Ju Tsai; Wei-An Chang; Ming-Shyan Huang; Po-Lin Kuo

    2014-01-01

    Recent advances in cancer therapy encounter a bottleneck. Relapsing/recurrent disease almost always developed eventually with resistance to the initially effective drugs. Tumor microenvironment has been gradually recognized as a key contributor for cancer progression, epithelial-mesenchymal transition of the cancer cells, angiogenesis, cancer metastasis, and development of drug resistance, while dysregulated immune responses and interactions between various components in the microenvironment ...

  6. Genetic parameters of productive and reproductive traits in Cinta Senese pig

    Directory of Open Access Journals (Sweden)

    O. Franci

    2010-01-01

    Full Text Available Cinta Senese breed, as other local breeds, suffered a bottleneck during the last century which produced a high level of inbreeding with a reduction of the productive and above all reproductive performances; average inbreeding coefficient of the piglets born in 2003 was 0.14 (Gandini and Gallo, 2004.

  7. Human demographic history: refining the recent African origin model.

    Science.gov (United States)

    Excoffier, Laurent

    2002-12-01

    Recent studies of large portions of the human genome support a recent origin of modern humans from an African stock after a bottleneck of moderate size followed by a range expansion out of Africa. Under this simple scenario, patterns of molecular diversity suggest that balancing selection could be more prevalent than positive selection in coding regions. PMID:12433581

  8. Identifying pathways for improving household food self-sufficiency outcomes in the hills of Nepal

    Science.gov (United States)

    Maintaining and improving food security in mountain regions is an ongoing challenge. There are many facets to the problem, including comparatively high levels of system diversity and crop-livestock integration, challenging terrain and transportation bottlenecks, declining labor availability due to o...

  9. Exploring Marine Environments To Unravel Tolerance Mechanisms To Relevant Compounds

    DEFF Research Database (Denmark)

    Machado, Henrique; Cavaleiro, Mafalda; Nørholm, Morten;

    2015-01-01

    major bottlenecks of this approach. Since then, tolerance engineering of microbial cell factories along with metabolic pathway engineering has been one of the main research focuses. Microorganisms with natural tolerance to relevant compounds, such as ρ-coumaric, glutaric and isobutyric acids were...

  10. Sustainable Development in the Core Water Resource Area of the Central Route of the South-to-North Water Transfer Project

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    With continued population growth and accelerated industrialization and urbanization, water shortages and water quality deterioration have become a bottleneck restraining global socioeconomic progress. In China, water resources are unevenly distributed, with abundance in the south and scarcity in the north. Every year, a loss of nearly 100 billion yuan is incurred by water shortages in the north.

  11. Breakdown and high-field reliability issues in heterojunction FETs for microwave power amplification

    OpenAIRE

    Menozzi, R.

    2000-01-01

    High-field reliability issues connected with hot electron and impact ionization are typically the reliability bottleneck of power FETs for microwave and millimeter-wave applications. This work deals with some aspects of this problem, from characterization and accelerated stressing techniques to the physical degradation mechanisms, using power AlGaAs/GaAs HFETs as a test vehicle.

  12. Assessing Researcher Interdisciplinarity: A Case Study of the University of Hawaii NASA Astrobiology Institute

    OpenAIRE

    Gowanlock, Michael G.; Gazan, Rich

    2012-01-01

    In this study, we combine bibliometric techniques with a machine learning algorithm, the sequential Information Bottleneck, to assess the interdisciplinarity of research produced by the University of Hawaii NASA Astrobiology Institute (UHNAI). In particular, we cluster abstract data to evaluate Thomson Reuters Web of Knowledge subject categories as descriptive labels for astrobiology documents, assess individual researcher interdisciplinarity, and determine where collaboration opportunities m...

  13. Electric power wheeling and dealing: Technological considerations for increasing competition. Volume 2. Contractor documents, Part B

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    The report reviews the technologies for electric power transmission and how it is employed by utilities. Contents: Case studies on increasing transmission access; Case studies of transmission bottlenecks; Technological considerations in proposed scenarios for increasing competition in the electric utility industry; Technical background and considerations in proposed increased wheeling, transmission access and non-utility generation.

  14. A Benchmarking Algorithm to Determine Minimum Aggregation Delay for Data Gathering Trees and an Analysis of the Diameter-Aggregation Delay Tradeoff

    Directory of Open Access Journals (Sweden)

    Natarajan Meghanathan

    2015-07-01

    Full Text Available Aggregation delay is the minimum number of time slots required to aggregate data along the edges of a data gathering tree (DG tree spanning all the nodes in a wireless sensor network (WSN. We propose a benchmarking algorithm to determine the minimum possible aggregation delay for DG trees in a WSN. We assume the availability of a sufficient number of unique CDMA (Code Division Multiple Access codes for the intermediate nodes to simultaneously aggregate data from their child nodes if the latter are ready with the data. An intermediate node has to still schedule non-overlapping time slots to sequentially aggregate data from its own child nodes (one time slot per child node. We show that the minimum aggregation delay for a DG tree depends on the underlying design choices (bottleneck node-weight based or bottleneck link-weight based behind its construction. We observe the bottleneck node-weight based DG trees incur a smaller diameter and a larger number of child nodes per intermediate node; whereas, the bottleneck link-weight based DG trees incur a larger diameter and a much lower number of child nodes per intermediate node. As a result, we observe a complex diameter-aggregation delay tradeoff for data gathering trees in WSNs.

  15. Energetic hydrogen in Brazil: subsidies for competitiveness police, 2010-2025. Critical and sensitive technologies in priority sectors; Hidrogenio energetico no Brasil: subsidios para politicas de competitividade, 2010-2025. Tecnologias criticas e sensiveis em setores prioritarios

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-08-15

    The report presents an introduction to the hydrogen technology, with proposals of incentives for hydrogen economy, hydrogen production, hydrogen logistic development and hydrogen use systems with relation to the internacional and national environment, considerations, bottlenecks and proposals and a synthetic chart of recommendations.

  16. Case studies on the use of biotechnologies and on biosafety provisions in four African countries

    OpenAIRE

    Black, R; F. Fava; Mattei, N.; Robert, Vincent; Seal, S; Verdier, Valérie

    2011-01-01

    This review is based on a study commissioned by the European Commission on the evaluation of scientific, technical and institutional challenges, priorities and bottlenecks for biotechnologies and regional harmonisation of biosafety in Africa. Biotechnology was considered within four domains: agricultural biotechnologies ('Green'), industrial biotechnologies and biotechnologies for environmental remediation ('White'), biotechnologies in aquaculture ('Blue') and biotechnologies for healthcare (...

  17. Effects of increasing docosahexaenoic acid and arachidonic acid in brood diets of monodactylus sebae on fecundity, egg and larval quality, and egg fatty acid composition

    Science.gov (United States)

    Monodactylus sebae is a popular euryhaline ornamental fish species with limited aquaculture production. One of the bottlenecks to their commercial production has been knowledge of broodstock nutritional requirements. Therefore, three brood diets were formulated and fed to M. sebae brood to determine...

  18. Dynamic Line Rating - Technologies and Challenges of PMU on Overhead Lines: A Survey

    DEFF Research Database (Denmark)

    Alvarez, David; Silva, Filipe Miguel Faria da; Bak, Claus Leth;

    2016-01-01

    This article reviews direct and indirect methods developed for dynamic line rating on overhead lines, and their applications (reduction of bottlenecks, congestion costs, load shedding, among others) in the operation and control of power systems as smart grid technology. Besides, four elements for...

  19. Making Biological Sense of GWAS Data: Lessons from the FTO Locus.

    Science.gov (United States)

    Herman, Mark A; Rosen, Evan D

    2015-10-01

    GWAS have yielded many candidate loci for complex diseases like obesity, but interpreting the biological context of these findings has been difficult. Claussnitzer et al. (2015) use a sophisticated combination of bioinformatic and experimental approaches to address this bottleneck for variants in the FTO locus that associate with obesity. PMID:26445508

  20. Inbreeding depression is purged in the invasive insect Harmonia axyridis

    Science.gov (United States)

    Invaders face a genetic barrier when they pass through bottlenecks in population size, which can reduce genetic diversity and increase inbreeding among close relatives. Although low fitness among consanguineous offspring, or inbreeding depression, is widespread, why it is that invaders appear not to...