960 resultados para Angola Benguela Front
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Three surveys were carried out in anchovy spawning periods in southern Yellow Sea in May and June 2001, and June 2002. Chlorophyll a (Chl-a) concentration, bacterioplankton abundance, biomass and their variations along the zone of tidal fronts were investigated. The results showed that (1) high Synechococcus abundance distributed more often in frontal area and middle-surface layer of a stratified zone; and (2) the maximal abundance of bacteria occurred in stratified and mixed zone. 2006 Elsevier B.V. All rights reserved.
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O sistema de cultivo em consórcio de fruteiras com outras culturas, sejam anuais, semiperenes ou perenes, constitui uma boa alternativa para propriedades rurais e uma importante forma de recuperação de áreas degradadas. O objetivo deste trabalho foi avaliar o comportamento de bananeira, cv. D'Angola, em monocultivo e consorciada com açaizeiro, Euterpe precatoria, em diferentes espaçamentos, no primeiro ciclo de produção. Para tanto, foi instalado um experimento seguindo um delineamento em blocos casualizados completos com quatro repetições e seis plantas por parcela. Os tratamentos foram: T1 ? bananeira em 3 m x 3 m (1.111 plantas ha-1); T2 ? bananeira em 3 m x 2 m (1.666 plantas ha-1) com açaizeiro em 3 m x 4 m (833 plantas ha-1); T3 ? bananeira em 3 m x 3 m (1.111 plantas ha-1) com açaizeiro em 3 m x 4 m (833 plantas ha-1); T4 ? bananeira em 4 m x 2 m x 2 m (1.666 plantas ha-1) com açaizeiro em 6 m x 3 m (555 plantas ha-1) e T5 ? bananeira em 4 m x 2 m x 2 m (1.666 plantas ha-1) com açaizeiro em 4 m x 2 m x 3 m (1.111 plantas ha-1). O sistema de cultivo da bananeira terra consorciada com açaizeiro em diferentes espaçamentos pode ser considerado como boa alternativa no primeiro ciclo, pois não apresentou interferência nas características de desenvolvimento, de produção e qualidade física dos frutos. Os plantios mais adensados propiciaram maiores produtividades no primeiro ciclo da cultura.
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O espaçamento é um dos principais fatores para aumento de produtividade, sem ocasionar perdas de qualidade de frutos da bananeira, e varia em função das condições de clima e solo da região. Quando a bananeira é cultivada em maiores densidades, aproveita-se melhor a área disponível e o uso da mão de obra é otimizado. Na banana-comprida o espaçamento ideal evita a competição por água, luz e nutrientes, sem comprometer os rendimentos potenciais da cultura.
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74 Front Street is intended as a musical response to the work of American sculptor Fred Sandback (1943-2003), in particular his string sculptures which are intentionally uncomplicated, minimal and strikingly beautiful. The relationship between these string works and music is rather distinct; indeed, before formally studying sculpture Sandback made a number of string instruments. He has said that his string works evolved from a desire to rid art of excessive decoration and, while there are instances of activity in 74 Front Street, much of the piece aims to reflect the simplicity of Sandback’s work.
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4.171 JCR (2013) Q1, 6/81 Sport sciences
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In this paper, a prototype of miniaturized, low power, bi-directional wireless sensor node for wireless sensor networks (WSN) was designed for doors and windows building monitoring. The capacitive pressure sensors have been developed particularly for such application, where packaging size and minimization of the power requirements of the sensors are the major drivers. The capacitive pressure sensors have been fabricated using a 2.4 mum thick strain compensated heavily boron doped SiGeB diaphragm is presented. In order to integrate the sensors with the wireless module, the sensor dice was wire bonded onto TO package using chip on board (COB) technology. The telemetric link and its capabilities to send information for longer range have been significantly improved using a new design and optimization process. The simulation tool employed for this work was the Designerreg tool from Ansoft Corporation.
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In the last decade, we have witnessed the emergence of large, warehouse-scale data centres which have enabled new internet-based software applications such as cloud computing, search engines, social media, e-government etc. Such data centres consist of large collections of servers interconnected using short-reach (reach up to a few hundred meters) optical interconnect. Today, transceivers for these applications achieve up to 100Gb/s by multiplexing 10x 10Gb/s or 4x 25Gb/s channels. In the near future however, data centre operators have expressed a need for optical links which can support 400Gb/s up to 1Tb/s. The crucial challenge is to achieve this in the same footprint (same transceiver module) and with similar power consumption as today’s technology. Straightforward scaling of the currently used space or wavelength division multiplexing may be difficult to achieve: indeed a 1Tb/s transceiver would require integration of 40 VCSELs (vertical cavity surface emitting laser diode, widely used for short‐reach optical interconnect), 40 photodiodes and the electronics operating at 25Gb/s in the same module as today’s 100Gb/s transceiver. Pushing the bit rate on such links beyond today’s commercially available 100Gb/s/fibre will require new generations of VCSELs and their driver and receiver electronics. This work looks into a number of state‐of-the-art technologies and investigates their performance restraints and recommends different set of designs, specifically targeting multilevel modulation formats. Several methods to extend the bandwidth using deep submicron (65nm and 28nm) CMOS technology are explored in this work, while also maintaining a focus upon reducing power consumption and chip area. The techniques used were pre-emphasis in rising and falling edges of the signal and bandwidth extensions by inductive peaking and different local feedback techniques. These techniques have been applied to a transmitter and receiver developed for advanced modulation formats such as PAM-4 (4 level pulse amplitude modulation). Such modulation format can increase the throughput per individual channel, which helps to overcome the challenges mentioned above to realize 400Gb/s to 1Tb/s transceivers.
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This thesis is a study of how the Gerald Ford administration struggled to address a perceived loss of US credibility after the collapse of Vietnam, with a focus on the role of Secretary of State Henry Kissinger in the formulation, implementation and subsequent defence of US Angolan policy. By examining the immediate post-Vietnam period, this thesis shows that Vietnam had a significant impact on Kissinger’s actions on Angola, which resulted in an ill conceived covert operation in another third world conflict. In 1974, Africa was a neglected region in Cold War US foreign policy, yet the effects of the Portuguese revolution led to a rapid decolonization of its African territories, of which Angola was to become the focus of superpower competition. After South Vietnam collapsed in April 1975, Kissinger became fixated on restoring the perceived loss of US prestige, Angola provided the first opportunity to address this. Despite objections from his advisors, Kissinger methodically engineered a covert program to assist two anti-Marxist guerrilla groups in Angola. As the crisis escalated, the media discovered the operation and the Congress decided to cease all funding. A period of heated tensions ensued, resulting in Kissinger creating a new African policy to outmanoeuvre his critics publicly, while privately castigating them to foreign leaders. This thesis argues that Kissinger’s dismissal of internal dissent and opposition from the Congress was influenced by what he perceived as bureaucrats being affected by the Vietnam syndrome, and his obsession with restoring US credibility. By looking at the private and public records – as expressed in government meetings and official reports, US newspaper and television coverage and diplomatic cables – this thesis addresses the question of how the lessons of Vietnam failed to influence Kissinger’s actions in Angola, but the lessons of Angola were heavily influential in the construction of a new US-African policy.
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The large seasonal migration of the transition zone chlorophyll front (TZCF) is of interest because a number of marine fauna, both commercial and endangered, appear to track it. Herein we examine the physical dynamics driving this seasonal migration of the TZCF. Vertical processes, traditionally viewed as controlling the dynamical supply of nutrients to surface waters, prove insufficient to explain seasonal variations in nutrient supply to the transition zone. Instead, we find that the horizontal Ekman transport of nutrients from higher latitudes drives the TZCF's southward migration. The estimated horizontal transport of nitrate supports up to 40% of new primary productivity in the region annually and nearly all of new primary productivity in the winter. The significance of horizontal advection to the North Pacific transition zone supports revising the paradigm that nutrients are supplied to surface waters from below. © 2010 by the American Geophysical Union.
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Electrodeposition is a widely used technique for the fabrication of high aspect ratio microstructures. In recent years, much research has been focused within this area aiming to understand the physics behind the filling of high aspect ratio vias and trenches on substrates and in particular how they can be made without the formation of voids in the deposited material. This paper reports on the fundamental work towards the advancement of numerical algorithms that can predict the electrodeposition process in micron scaled features. Two different numerical approaches have been developed, which capture the motion of the deposition interface and 2-D simulations are presented for both methods under two deposition regimes: those where surface kinetics is governed by Ohm’s law and the Butler–Volmer equation, respectively. In the last part of this paper the modelling of acoustic forces and their subsequent impact on the deposition profile through convection is examined.
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No abstract is available for this article.
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The position and structure of the North Atlantic Subtropical Front is studied using Lagrangian flow tracks and remote sensing (AVHRR imagery: TOPEX/POSEIDON altimetry: SeaWiFS) in a broad region ( similar to 31 degree to similar to 36 degree N) of marked gradient of dynamic height (Azores Current) that extends from the Mid-Atlantic Ridge (MAR), near similar to 40 degree W, to the Eastern Boundary ( similar to 10 degree W). Drogued Argos buoy and ALACE tracks are superposed on infrared satellite images in the Subtropical Front region. Cold (cyclonic) structures, called storms, and warm (anticyclonic) structures of 100-300 km in size can be found on the south side of the Subtropical Front outcrop, which has a temperature contrast of about 1 degree C that can be followed for similar to 2500 km near 35 degree N. Warmer water adjacent to the outcrop is flowing eastward (Azores Current) but some warm water is returned westward about 300 km to the south (southern Counterflow). Estimates of horizontal diffusion in a Storm (D=2.2t10 super(2) m super(2) s super(-1)) and in the Subtropical Front region near 200 m depth (D sub(x)=1.3t10 super(4) m super(2) s super(-1), D sub(y)=2.6t10 super(3) m super(2) s super(-1)) are made from the Lagrangian tracks. Altimeter and in situ measurements show that Storms track westwards. Storms are separated by about 510 km and move westward at 2.7 km d super(-1). Remote sensing reveals that some initial structures start evolving as far east as 23 degree W but are more organized near 29 degree W and therefore Storms are about 1 year old when they reach the MAR (having travelled a distance of 1000 km). Structure and seasonality in SeaWiFS data in the region is examined.