نتایج جستجو برای: sources and sinks

تعداد نتایج: 16849795  

Journal: :ژورنال بین المللی پژوهش عملیاتی 0
f. hamzezadeh h. salehi fathabadi

in this article we present an algorithm for converting a network problem with several sources and several sinks including several transfer nodes and condition of supplying the demand of any sink from a particular source to the transportation problem.  towards this end, and considering the very special structure of transportation algorithm, after implementing the shortest path algorithm or solvi...

2006
Piet Groeneboom

Let P1 be a Poisson process of intensity λ1 on the positive x-axis, P2 a Poisson process of intensity λ2 on the positive y-axis, and P a Poisson process of intensity λ1λ2 in the interior of IR +, where P1, P2 and P are independent. Then the extended Hammersley process Lλ1(·, t) with sources and sinks given by P1 and P2, respectively, is distributed as a Poisson point process with intensity λ1 f...

2012
K. J. DAVIS

Recent instrumental deployments of regional observation networks of atmospheric CO2 mixing ratios have been used to constrain carbon sources and sinks using inversion methodologies. In this study, we performed sensitivity experiments using observation sites from the Mid Continent Intensive experiment to evaluate the required spatial density and locations of CO2 concentration towers based on flu...

Journal: :Environmental science & technology 2011
Mark Anthony Browne Phillip Crump Stewart J Niven Emma Teuten Andrew Tonkin Tamara Galloway Richard Thompson

Plastic debris <1 mm (defined here as microplastic) is accumulating in marine habitats. Ingestion of microplastic provides a potential pathway for the transfer of pollutants, monomers, and plastic-additives to organisms with uncertain consequences for their health. Here, we show that microplastic contaminates the shorelines at 18 sites worldwide representing six continents from the poles to the...

2008
Raffaele Ferrari Carl Wunsch

The ocean circulation is a cause and consequence of fluid scale interactions from millimeters to 10,000km. Although the wind field produces a large energy input to the ocean, all but about 10% appears to be dissipated within about 100m of the sea surface, rendering very difficult observations of the energy divergence necessary to maintain the full water column flow. Attention thus shifts to the...

Journal: :Biology letters 2015
Pablo Munguia

Spatially structured habitats challenge populations to have positive growth rates and species often rely on dispersing propagules to occupy habitats outside their fundamental niche. Most marine species show two main life stages, a dispersing stage and a sedentary stage affecting distribution and abundance patterns. An experimental study on Corophium acherusicum, a colonial tube-building amphipo...

2015
A. Ghosh P. K. Patra K. Ishijima T. Umezawa A. Ito D. M. Etheridge S. Sugawara K. Kawamura J. B. Miller E. J. Dlugokencky P. B. Krummel P. J. Fraser L. P. Steele R. L. Langenfelds C. M. Trudinger J. W. C. White B. Vaughn T. Saeki S. Aoki T. Nakazawa

Atmospheric methane (CH4) increased from ∼900 ppb (parts per billion, or nanomoles per mole of dry air) in 1900 to ∼1800 ppb in 2010 at a rate unprecedented in any observational records. However, the contributions of the various methane sources and sinks to the CH4 increase are poorly understood. Here we use initial emissions from bottom-up inventories for anthropogenic sources, emissions from ...

2009
Hyejin Youn Michael T. Gastner Hawoong Jeong

We study the problem of optimizing traffic in decentralized transportation networks, where the cost of a link depends on its congestion. If users of a transportation network are permitted to choose their own routes, they generally try to minimize their personal travel time. In the absence of centralized coordination, such a behavior can be inefficient for society and even for each individual us...

2008
S. Carmi Z. Wu S. Havlin H. E. Stanley

We investigate the electrical current and flow (number of parallel paths) between two sets of n sources and n sinks in complex networks. We derive analytical formulas for the average current and flow as a function of n. We show that for small n, increasing n improves the total transport in the network, while for large n bottlenecks begin to form. For the case of flow, this leads to an optimal n...

2009
Nicolas Gruber Manuel Gloor Sara E. Mikaloff Fletcher Scott C. Doney Stephanie Dutkiewicz Michael J. Follows Markus Gerber Andrew R. Jacobson Fortunat Joos Keith Lindsay Dimitris Menemenlis Anne Mouchet Simon A. Müller Jorge L. Sarmiento Taro Takahashi

[1] We synthesize estimates of the contemporary net air-sea CO2 flux on the basis of an inversion of interior ocean carbon observations using a suite of 10 ocean general circulation models (Mikaloff Fletcher et al., 2006, 2007) and compare them to estimates based on a new climatology of the air-sea difference of the partial pressure of CO2 (pCO2) (Takahashi et al., 2008). These two independent ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید