Discharge estimation in a backwater affected meandering river

Variable effects of backwaters complicate the development of rating curves at hydrometric measurement stations. In areas influenced by backwater, single-parameter rating curve techniques are often inapplicable. To overcome this, several authors have advocated the use of an additional downstream level gauge to estimate the longitudinal surface level gradient, but this is cumbersome in a lowland meandering river with considerable transverse surface level gradients. Recent developments allow river flow to be continuously monitored through velocity measurements with an acoustic Doppler current profiler (H-ADCP), deployed horizontally at a river bank. This approach was adopted to obtain continuous discharge estimates at a cross-section in the River Mahakam at a station located about 300 km upstream of the river mouth in the Mahakam delta. The discharge station represents an area influenced by variable backwater effects from lakes, tributaries and floodplain ponds, and by tides. We applied both the standard index velocity method and a recently developed methodology to obtain a continuous time-series of discharge from the H-ADCP data. Measurements with a boat-mounted ADCP were used for calibration and validation of the model to translate H-ADCP velocity to discharge. As a comparison with conventional discharge estimation techniques, a stage-discharge relation using Jones formula was developed. The discharge rate at the station exceeded 3300 m3 s-1. Discharge series from a traditional stage-discharge relation did not capture the overall discharge dynamics, as inferred from H-ADCP data. For a specific river stage, the discharge range could be as high as 2000 m3 s-1, which is far beyond what could be explained from kinematic wave dynamics. Backwater effects from lakes were shown to be significant, whereas the river-tide interaction may impact discharge variation in the fortnightly frequency band. Fortnightly tides cannot easily be isolated from river discharge variation, which features similar periodicitie

Transmutation in 90SrF2: A density functional theory study of phase stability in ZrF2

The stability of multiple possible phases of ZrF2 is computed using density-functional theory. Motivated by radioactive samples of fluorite 90SrF2 stored at the Hanford site, we consider β− radioactive decay as the route by which the 90ZrF2 is generated. To find suitable structures for the ZrF2 compound two methodologies are used. The first follows imaginary phonon modes from the fluorite ZrF2 while the second employs random structure searching. Six possible ZrF2 phases are identified; however, none of the structures resemble the lone experimentally reported orthorhombic structure for ZrF2. Although we predict these phases to be less stable (~0.3 eV/f.u.) than a phase-decomposed mixture of β-ZrF4 and Zr metal, they still may be relevant due to the kinetics of formation via radioactive decay and raise questions as to the nature of the ZrF2 structure and the state of the samples at Hanford

What is the impact of food reformulation on individual’s behaviour, nutrient intakes and health status? A systematic review of empirical evidence

Food reformulation aimed at improving the nutritional properties of food products has long been viewed as a promising public health strategy to tackle poor nutrition and obesity. This paper presents a review of the empirical evidence (i.e. modelling studies were excluded) on the impact of food reformulation on food choices, nutrient intakes and health status, based on a systematic search of Medline, Embase, Global Health, and sources of grey literature. Fifty-nine studies (in 35 papers) were included in the review. Most studies examined food choices (n=27) and dietary intakes (n=26). The nutrients most frequently studied were sodium (n=32) and trans-fatty acids (TFA, n=13). Reformulated products were generally accepted and purchased by consumers, which led to improved nutrient intakes in 73% of studies. We also conducted two meta-analyses showing, respectively, a -0.57g/day [95%CI -0.89, -0.25] reduction in salt intake, and an effect size for TFA intake reduction of -1.2, 95% [CI -1.79, -0.61]. Only six studies examined effects on health outcomes, with studies on TFA reformulation showing overall improvement in cardiovascular risk factors. For other nutrients, it remains unclear whether observed improvements in food choices or nutrient intakes may have led to an improvement in health outcomes

Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transpot project-demonstration act system definition

The 1985 ACT airplane is the Final Active Controls Technology (ACT) Airplane with the addition of three-axis fly by wire. Thus it retains all the efficiency features of the full ACT system plus the weight and cost savings accruing from deletion of the mechanical control system. The control system implements the full IAAC spectrum of active controls except flutter-mode control, judged essentially nonbeneficial, and incorporates new control surfaces called flaperons to make the most of wing-load alleviation. This redundant electronic system is conservatively designed to preserve the extreme reliability required of crucial short-period pitch augmentation, which provides more than half of the fuel savings

Variação sazonal do fitoplâncton da região do Saco da Ribeira (lat. 23º30'S; long, 45º07'W), Ubatuba, Brasil

Seasonal changes in phytoplankton populations in the chlorophyll-a concentration and on some environmental factors were studied monthly from June 1974 to September 1975 at Ubatuba, northern coast of São Paulo. Water temperatures ranged from 20ºC in August to 29.5ºC in March and salinities from 33.06 º/.. in March to 35.80 º/.. in January. The maximum salinity value observed in January near the bottom, associated with the thermal stratification found only during this month, seems to indicate an oceanic contribution to the enrichment of the local water mass. Pluviometric values ranged from 37.2 mm in August to 468.5 mm in January. Phytoplankton cell counts fluctuated from 64,000 to 1,028,000 cells/l and chlorophyll-a values varied from 0.52 to 6.86 µg/l. Maximum standing-stock was observed during summer, particularly in March, and it is probably associated with land drainage due to precipitation. A second bloom was observed in September 1975, and it is associated probably with the discontinuous impact of the wind. The phytoplankton populations were dominated by unidentified phytoflagellates, followed by diatoms and dinoflagellates. Nitzchia closterium and Thalassionema nitzschioides, along with Navicula sp., were the most representative species of diatoms. Among the dinoflagellates, Gymnodinium sp. was the most important. Blue-green algae and silicoflagellates were poorly represented. The diatoms Chaetoceros simplex, Chaetoceros spp, Nitzchia longissima, Nitzchia spp, Rhizosolenia delicatula and Rhizosolenia stolterfothi were found with high densities, only during bloom periods. The chlorophyll-a fractionation experiments demonstrated that organisms in size classe smaller than 20 µm represented, for all depths, between 54.93 and 98.15 º/.. of the total phytoplankton population.Estudos sobre a variação sazonal do fitoplâncton e clorofila-a foram desenvolvidos na região de Ubatuba, extremo norte do Estado de São Paulo (Lat. 23º30'S, Long. 45º07'W), através de coletas mensais, durante o período de junho de 1974 a setembro de 1975. Foram também avaliados a temperatura da água, salinidade, oxigênio dissolvido e transparência. Paralelamente, foram obtidos dados pluviométricos da região, referentes ao período considerado. As amostras destinadas aos referidos estudos foram coletadas verticalmente, em três níveis de profundidade: superfície, profundidade de extinção do disco de Secchi e 60 centímetros acima do fundo. Qualitativamente, as diatomáceas apresentaram-se como o grupo mais diversificado e, em segundo lugar, os dinoflagelados. Quantitativamente, a população fitoplanctônica apresentou-se constituída fundamentalmente por fitoflagelados, seguidos por diatomáceas e dinoflagelados. Cianofíceas e silicoflagelados também estiveram presentes, porém em quantidades muito menores. Excluindo-se os fitoflagelados, as espécies mais representativas da população fitoplanctônica da região foram as diatomáceas Nitzchia closterium, Thalassionema nitzschioides, Navicula sp. e o dinoflagelado Gymnodinium sp. O número máximo de células observado, de um modo geral, ocorreu durante o verão, evidenciado tanto pelas contagens (máximo de 1.028.000 células/litro), como pelas determinações de clorofila-a (máximo de 6,86 µg/1); nesta época, houve um máximo de precipitação pluviométrica e modificação na estabilidade térmica da coluna d'água. Os estudos de fracionamento demonstraram que a fração menor que 20 µm (nanofitoplâncton) é a predominante no fitoplâncton total

Hydrogen Bond Disruption in DNA Base Pairs from 14C Transmutation

Recent ab initio molecular dynamics simulations have shown that radioactive carbon does not normally fragment DNA bases when it decays. Motivated by this finding, density functional theory and Bader analysis have been used to quantify the effect of C → N transmutation on hydrogen bonding in DNA base pairs. We find that 14C decay has the potential to significantly alter hydrogen bonds in a variety of ways including direct proton shuttling (thymine and cytosine), thermally activated proton shuttling (guanine), and hydrogen bond breaking (cytosine). Transmutation substantially modifies both the absolute and relative strengths of the hydrogen bonding pattern, and in two instances (adenine and cytosine), the density at the critical point indicates development of mild covalent character. Since hydrogen bonding is an important component of Watson-Crick pairing, these 14C-induced modifications, while infrequent, may trigger errors in DNA transcription and replication

FRAMEWORK ITIL E INTELIGÊNCIA COMPUTACIONAL NA PADRONIZAÇÃO DO ATENDIMENTO DO SERVICE DESK DE UM HOSPITAL PÚBLICO

Service Desk é onde processos e serviços são projetados de forma a assegurar qualidade e satisfação do cliente. No hospital público estudado existe a falta de padronização no atendimento do Service Desk. Existem modelos que auxiliam no controle de processos e serviços como, por exemplo, o ITIL (Information Technology Infrastructure Library) que é modelo de boas práticas no tratamento de processos e serviços da Tecnologia da Informação. Técnicas da inteligência computacional como Rede Neural Artificial e Sistema Especialista podem ser associadas para padronizar o atendimento no Service Desk. O objetivo deste trabalho foi utilizar o ITIL e aplicar técnicas de inteligência computacional na padronização do atendimento do Service Desk de um hospital público. Duas técnicas foram associadas para atingir o objetivo do trabalho, uma Rede Neural Artificial do tipo Mapa Auto Organizável de Kohonen com um Sistema Especialista na padronização do atendimento ao usuário no Service Desk. do hospital público. Para  realizar os experimentos  utilizou-se uma base de dados de atendimentos com 10.048 registros de ocorrências cadastradas compreendendo o ano de 2002 ao ano de 2012. Concluiu-se que a aplicação do ITIL e da inteligência computacional na padronização no atendimento do Service Desk. foi possível e apresentou resultados interessantes

Flow and Heat Transfer during an Expansion Stroke in a Composite Fluid/Porous System

The purpose of this study is to analyze the fluid flow and heat transfer in a pipe partially filled with porous media and provided with a flat piston during an expansion stroke. In addition to the Navier-Stokes equation for the fluid region, Brinkman-Forchheimer-Lapwood-extended Darcy’s model is introduced into the numerical solver to simulate flow and heat transfer in the porous insert. The heat transfer in porous media is studied by using the assumption of local thermal equilibrium. The discretization procedure is based on Control-Volume-based Finite Element Method. The coupled pressure-velocity equations are solved using the SIMPLER algorithm. This investigation concerns the hydrodynamic characteristics, using the Reynolds numbers and the porosity effects, and the heat transfer characteristics using the heat capacity and the thermal conductivity ratios effects