Exploitation of SAR data for measurement of ocean currents and wave velocities

Methods of extracting information on ocean currents and wave orbital velocities from SAR data by an analysis of the Doppler frequency content of the data are discussed. The theory and data analysis methods are discussed, and results are presented for both aircraft and satellite (SEASAT) data sets. A method of measuring the phase velocity of a gravity wave field is also described. This method uses the shift in position of the wave crests on two images generated from the same data set using two separate Doppler bands. Results of the current measurements are pesented for 11 aircraft data sets and 4 SEASAT data sets

Evaluation of ERIM optically processed SEASAT SAR data

The results of three studies on the radiometric and geometric properties of optically processed SEASAT SAR imagery are summarized. The accuracy with which the image scale can be predicted based upon a knowledge of the SAR platform and recording system parameters and the processor characteristics was evaluated. The considerations involved in making radiometric measurements from image films, the use of point targets for calibrating the effects of Doppler spectrum shifts on the radiometric calibration of the SAR image data over extended swath lengths was evaluate

A risky bet: Climate change and the EU’s microprudential framework of banks

Banking regulation and supervision have a key role to play in realizing the EU’s climate change objectives. In this article, we analyse the EU-level initiatives currently underway to decarbonize the banking system, in particular with regard to the microprudential rulebook. We document how regulators work hard to fit climate policy into the existing objectives of the microprudential framework. We also assess whether these efforts are likely to be successful by sketching two ways forward, which involve their own distinct hazards. The first is a ‘Deferential Transition’, which sees policymakers rely on banks and external rating providers to develop adequate internal risk management procedures while taking a largely agnostic approach as to what methodologies are appropriate. If this is the way forward, we see a number of risks: banks have a clear incentive to downplay risk, while large financial institutions gain a significant advantage and the division of responsibility between banks and supervisors becomes blurred. We also outline the scenario of a ‘Guided Transition’, in which regulators provide fine-grained guidance on the future that banks should anticipate. Although we broadly think this approach is the more effective route to greening EU banking, we also see challenges of an entirely different sort: regulators will unavoidably face political choices and EU lawmakers will need to consider issues of legality, legitimacy, and accountability. In this regard, we argue, the EU faces a risky bet

Studies on the amount and composition of digesta flowing through the duodenum of dairy cows. 2. Sites of net absorption of magnesium and calcium from the alimentary tract.

Two cows were fitted with re-entrant duodenal cannulas, and four with T-piece duodenal annulas. Balance trials were carried out, the cows receiving either a winter ration, or freshly-mown herbage. Direct measurements were made of the flow of digesta, and of the amounts of Mg and Ca in both duodenal and faecal samples. Also indirect measurements were made of these parameters, using polyethylene glycol and chromium sesquioxide indicators. Net Ca absorption was restricted to the intestines, and, at high Mg intake, net Mg absorption was also largely intestinal, though too large an error attached to the indirect measurement of Mg absorption rates for reliable conclusions to be drawn. There was considerable secretion of Ca proximal to the duodenum. (Abstract retrieved from CAB Abstracts by CABI’s permission

Terrestrial carbon sinks for the United States Predicted from MODIS satellite data and ecosystem modeling

A simulation model based on satellite observations of monthly vegetation cover from the Moderate Resolution Imaging Spectroradiometer (MODIS) was used to estimate monthly carbon fluxes in terrestrial ecosystems of the conterminous United States over the period 2001-04. Predicted net ecosystem production (NEP) flux for atmospheric CO2 in the United States was estimated as annual net sink of about +0.2 Pg C in 2004. Regional climate patterns were reflected in the predicted annual NEP flux from the model, which showed extensive carbon sinks in ecosystems of the southern and eastern regions in 2003-04, and major carbon source fluxes from ecosystems in the Rocky Mountain and Pacific Northwest regions in 2003-04. As demonstrated through tower site comparisons, net primary production (NPP) modeled with monthly MODIS enhanced vegetation index (EVI) inputs closely resembles both the measured high- and low-season carbon fluxes. Modeling results suggest that the capacity of the NASA Carnegie Ames Stanford Approach (CASA) model to use 8-km resolution MODIS EVI data to predict peak growing season uptake rates of CO2 in irrigated croplands and moist temperate forests is strong

Nitrate poisoning in cattle. 3. The relationship between nitrate intake with hay or fresh roughage and the speed of intake on the formation of methemoglobin.

For part 2 see NAR/B 48, 238. 3. In 40 feeding experiments during about 5 years dry or lactating Friesian cows weighing 415 to 670 kg and 3 to 8 years old were given diets of hay, grass pellets, turnips or freshly mown grass in 2 meals daily. During experiments blood from the jugular vein was sampled every 15 min. Cows were induced to increase nitrate intake by being given at least 4 meals of roughage rich in nitrate before blood was sampled. There was a positive relation between nitrate intake and methaemoglobin per cent of total Hb but there were differences within and between different roughages in formation of methaemoglobin. With similar nitrate intake and speed of intake, more Hb was converted into methaemoglobin with hay than with freshly mown grass. That was related to the speed at which the nitrate taken with the roughage was released in the rumen as a substrate for the rumen flora. When hay was soaked in distilled water 80% of the nitrate in the cells diffused into the water within 20 min. With turnip and grass chopped to about 1 cm, 30% of the nitrate diffused into the water within 20 min. (Abstract retrieved from CAB Abstracts by CABI’s permission

Nitrate poisoning in cattle. 7. Prevention.

Results are summarized from 44 feeding trials with dry or lactating cows fed hay, pre-wilted grass silage or freshly mown grass with or without concentrates. As nitrate content of the forage increased, the moment at which the highest methaemoglobin (MHb) concentration occurred was delayed. As the MHb peak increased, more time was required to reduce MHb to normal values of 2-3%. Dry matter (DM) intake varied with type of forage. Consumption of 1.1 kg DM/100 kg bodyweight required 2 hours with hay or silage and 3.5 h with fresh grass. The relationship between nitrate intake and the formation of MHb in the blood was used to calculate the amount of forage that may be consumed per meal without causing symptoms of nitrate poisoning. Hay and pre-wilted silage with a nitrate content of up to 0.75% in the DM may be given ad lib. Indoor feeding of freshly mown grass with a nitrate content of up to 1.5% may also be given with restriction. Under grazing conditions, grass with a nitrate content of 2% in DM was safe without restriction. Nitrate poisoning may also be prevented by inhibiting nitrate reduction in the rumen by a daily dose of tungsten (wolfram). However, all potential hazards of this prophylactic treatment need to be examined before its use under practical conditions can be recommended. (Abstract retrieved from CAB Abstracts by CABI’s permission

Design of a ring resonator-based optical beam forming network for phased array receive antennas

A novel squint-free ring resonator-based optical beam forming network (OBFN) for phased array antennas (PAA) is proposed. It is intended to provide broadband connectivity to airborne platforms via geostationary satellites. In this paper, we present the design of the OBFN and its control system. Our goal is to deliver large bandwidth Ku-band connectivity between antennas, mount conformal to the airplane fuselage and on a geostationary satellite, respectively.This way it would be possible to bring live DVB-S television to airplane passengers. In this paper, we present recent research conducted on a 4 × 1 ring resonator-based OBFN test set-up. This OBFN has four optical input ports and one optical output port. It is tuned to provide the desired signal combination with optimal constructive interference between the modulated input signals from the PAA. Therefore, combining circuitry and delay elements are required. The OBFN is tuned by electrically heating tunable true time delay (TTD) elements. These are built using optical ring resonators (ORRs). By cascading multiple ORRs with different resonance frequencies, it is possible to create a TTD with a large bandwidth. Optical beam forming is used because it provides advantages over traditional beam forming methods. These advantages are: large bandwidth, EMI resistance, and, when integrated onto a single chip, compactness and low costs. The OBFN is created using planar optical waveguide technology and consists of the following building blocks: waveguides, Mach-Zehnder interferometers, (MZIs) couplers and ORRs. The tuning of the OBFN is done by an electronic control system using a microcontroller. Communication with a PC is possible using USB. To our knowledge, this is the first integrated ORR-based OBFN circuit for PAA satellite reception