3,046,812 research outputs found
International Conference on Irrigation Management Transfer, Wuhan, China, 20-24 September 1994. Vol.3. Draft conference papers.
Irrigation managementIrrigation systemsFarmer participationPrivatizationSocial aspectsFarmers' associationsWater users' associationsTrainingPolicyFarmer participationEconomic aspectsFarmer managed irrigation systemsIrrigation programsRehabilitationWater resource management
Application of Electrical Properties to Differentiate Lard From Tallow and Palm Oil
This study aimed to differentiate lard from tallow and palm oil based on its electrical properties, namely conductance, impedance and capacitance. These properties were measured at spectra frequencies of 4.20 to 5.00 MHz in room temperature (26-27 oC). Statistic multivariate that consist on principal component analysis (PCA) and cluster analysis (CA) were used to evaluate the data. The results showed that lard and tallow can be differentiated using whole parameters electrical properties of materials. On the other hand, lard and palm oil can only be differentiated using part of the material electrical properties. Good performance of differentiation process was obtained using PCA model at 4.91 to 4.98 MHz. The first two components of PCA, which was derived from conductance, impedance and capacitance, contributed more than 90% of the total variances. CA showed that lard and tallow are different groups based on the Euclidean distance of each electrical properties. This technique can be potentially developed as an electrical sensor for differentiation lard to tallow and palm oil
Electrical Conductivity Protocol
The purpose of this resource is to measure the conductivity of water at a freshwater hydrology site. Students calibrate and take electrical conductivity measurements using an electrical conductivity meter. Students estimate the total dissolved solids from the electrical conductivity measurements. Educational levels: Intermediate elementary, Middle school, High school, Primary elementary
Acousto-electrical speckle pattern in Lorentz force electrical impedance tomography
Ultrasound speckle is a granular texture pattern appearing in ultrasound
imaging. It can be used to distinguish tissues and identify pathologies.
Lorentz force electrical impedance tomography is an ultrasound-based medical
imaging technique of the tissue electrical conductivity. It is based on the
application of an ultrasound wave in a medium placed in a magnetic field and on
the measurement of the induced electric current due to Lorentz force. Similarly
to ultrasound imaging, we hypothesized that a speckle could be observed with
Lorentz force electrical impedance tomography imaging. In this study, we first
assessed the theoretical similarity between the measured signals in Lorentz
force electrical impedance tomography and in ultrasound imaging modalities. We
then compared experimentally the signal measured in both methods using an
acoustic and electrical impedance interface. Finally, a bovine muscle sample
was imaged using the two methods. Similar speckle patterns were observed. This
indicates the existence of an "acousto-electrical speckle" in the Lorentz force
electrical impedance tomography with spatial characteristics driven by the
acoustic parameters but due to electrical impedance inhomogeneities instead of
acoustic ones as is the case of ultrasound imaging
Apparatus for measuring electrical properties of materials
Resistance of sample is measured with aid of usual electrical test instruments applied to electrical contacts provided at ram and anvil assemblies. Temperature differential is established between ram and anvil for measurement of Seebeck coefficient. Voltage generated across sample is detected at electrical contacts
A communication model of broadcast in wormhole-routed networks on-chip
This paper presents a novel analytical model to compute communication latency of broadcast as the most fundamental collective communication operation. The novelty of the model lies in its ability to predict the broadcast communication latency in wormhole-routed architectures employing asynchronous multi-port routers scheme. The model is applied to the Quarc NoC and its validity is verified by comparing the model predictions against the results obtained from a discrete-event simulator developed using OMNET++
Lorentz Force Electrical Impedance Tomography
This article describes a method called Lorentz Force Electrical Impedance
Tomography. The electrical conductivity of biological tissues can be measured
through their sonication in a magnetic field: the vibration of the tissues
inside the field induces an electrical current by Lorentz force. This current,
detected by electrodes placed around the sample, is proportional to the
ultrasonic pressure, to the strength of the magnetic field and to the
electrical conductivity gradient along the acoustic axis. By focusing at
different places inside the sample, a map of the electrical conductivity
gradient can be established. In this study experiments were conducted on a
gelatin phantom and on a beef sample, successively placed in a 300 mT magnetic
field and sonicated with an ultrasonic transducer focused at 21 cm emitting 500
kHz bursts. Although all interfaces are not visible, in this exploratory study
a good correlation is observed between the electrical conductivity image and
the ultrasonic image. This method offers an alternative to detecting
pathologies invisible to standard ultrasonography
A daily representation of Great Britain's energy vectors : Natural gas, electricity and transport fuels
In much of Europe there is a strong push to decarbonise energy demands, including the largest single end-use demand – heat. Moving heat demands over to the electrical network poses significant challenges and the use of hybrid energy vector and storage systems (heat and electrical storage) will be a critical component in managing this transition. As an example of these challenges (facing many developed countries), the scale of recently available daily energy flows through the UK’s electrical, gas and transport systems are presented. When this data is expressed graphically it illustrates important differences in the demand characteristics of these different vectors; these include the quantity of energy delivered through the networks on a daily basis, and the scale of variability in the gas demand over multiple timescales (seasonal, weekly and daily). As the UK proceeds to migrate heating demands to the electrical network in its drive to cut carbon emissions, electrical demand will significantly increase. Additionally, the greater variability and uncertainty shown in the gas demand will also migrate to the electrical demand posing significant difficulties for the maintenance of a secure and reliable electrical system in the coming decades. The paper concludes an analysis of the different means of accommodating increasingly volatile electricity demands in future energy networks
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