1,644 research outputs found
Drying cut fruits with recirculated air for energy savings
The main focus of this study was to test the feasibility of saving energy while drying fruit by recirculating drying air at a constant rate. Four recirculation rates (0, 25, 50, and 75%) were used to dry peaches and apples. For these treatments, the amount of energy consumed, the moisture removed, and the total drying times were measured. Three quantitative parameters (color, shelf-life, and sugar content) were used to determine the final quality of the dried fruit.
For both fruits tested, total energy consumption showed very significant differences among recirculation rates (with 75% recirculation requiring the least energy). The 75% recirculation rate produced an energy savings over no recirculation of approximately 53% for drying peaches and 46% for drying apples. The total processing times, however, were nearly the same for all recirculation rates. In general, no substantial losses occurred in the product quality for fruits subjected to the higher recirculation rates as compared to those subjected to no recirculation. The results of this experiment helped to decide an optimal fixed recirculation rate for maximizing the energy savings without causing destruction in the product quality. By optimizing the energy saved, fruit dehydrators may be improved to produce dried fruits at a lower cost
Supercritical carbon dioxide extraction of lipids from Pythium irregulare
Lipids that contain polyunsaturated fatty acids (PUFA) have therapeutic value. Supercritical carbon dioxide extraction of PUFA from the lower fungi, Pythium irregulare was attempted for freeze-dried material in the presence of an aqueous phase. Extraction showed some success at moisture contents up to 30% (wb) and with the addition of a novel CO2 -philic surfactant. Equilibrium and kinetic data are presented. Equilibrium data were taken for the fungal oil in a flow-through apparatus at a low flow rate for two isotherms (40 and 60°C) over a pressure range of 13.7 to 27.5 MPa. Equilibrium data were also taken for pure naphthalene at 40°C to test the system. The compressed-gas model utilizing the Peng-Robinson equation of state was then applied to the data. The kinetic data portrayed three types of mass transfer behavior including an initial surface-film regime where pseudo steady-state conditions prevailed, a diffusion-controlled regime where unsteady-state conditions were evident and a temporary transition region. For tests with extraction times of 5 to 6 hours, data for the diffusion-controlled region were modeled with an analytical solution to Fick\u27s Second Law assuming the particles were spherical shaped. The models worked well for both equilibrium and kinetic data, however the physical property values for the equilibrium data were altered substantially to obtain a reasonable fit with the compressed-gas model
“speaking base approbious words”: Speech Representation in Early Modern English Witness Depositions
This is the author's accepted manuscript. Copyright 2016, John Benjamins Publishing Company, Contact the publisher for permission to re-use or reprint the material in any form.This article explores the representation of speech in Early Modern English witness depositions. We demonstrate
that Semino and Short’s (2004) framework of description, which has for the most part been used in explorations
of present-day texts, is generally applicable to our historical data. Our study shows that factors such as the
importance of the evidence cited and the clarity of the deposition narrative were crucial considerations in
representing speech in different contexts
Solar Enablement Initiative in Australia: Report on Efficiently Identifying Critical Cases for Evaluating the Voltage Impact of Large PV Investment
The increasing quantity of PV generation connected to distribution networks
is creating challenges in maintaining and controlling voltages in those
distribution networks. Determining the maximum hosting capacity for new PV
installations based on the historical data is an essential task for
distribution networks. Analyzing all historical data in large distribution
networks is impractical. Therefore, this paper focuses on how to time
efficiently identify the critical cases for evaluating the voltage impacts of
the new large PV applications in medium voltage (MV) distribution networks. A
systematic approach is proposed to cluster medium voltage nodes based on
electrical adjacency and time blocks. MV nodes are clustered along with the
voltage magnitudes and time blocks. Critical cases of each cluster can be used
for further power flow study. This method is scalable and can time efficiently
identify cases for evaluating PV investment on medium voltage networks
Big-bang nucleosynthesis revisited
The homogeneous big-bang nucleosynthesis yields of D, He-3, He-4, and Li-7 are computed taking into account recent measurements of the neutron mean-life as well as updates of several nuclear reaction rates which primarily affect the production of Li-7. The extraction of primordial abundances from observation and the likelihood that the primordial mass fraction of He-4, Y(sub p) is less than or equal to 0.24 are discussed. Using the primordial abundances of D + He-3 and Li-7 we limit the baryon-to-photon ratio (eta in units of 10 exp -10) 2.6 less than or equal to eta(sub 10) less than or equal to 4.3; which we use to argue that baryons contribute between 0.02 and 0.11 to the critical energy density of the universe. An upper limit to Y(sub p) of 0.24 constrains the number of light neutrinos to N(sub nu) less than or equal to 3.4, in excellent agreement with the LEP and SLC collider results. We turn this argument around to show that the collider limit of 3 neutrino species can be used to bound the primordial abundance of He-4: 0.235 less than or equal to Y(sub p) less than or equal to 0.245
PC-CUBE: A Personal Computer Based Hypercube
PC-CUBE is an ensemble of IBM PCs or close compatibles connected in the hypercube topology with ordinary computer cables. Communication occurs at the rate of 115.2 K-band via the RS-232 serial links. Available for PC-CUBE is the Crystalline Operating System III (CrOS III), Mercury Operating System, CUBIX and PLOTIX which are parallel I/O and graphics libraries. A CrOS performance monitor was developed to facilitate the measurement of communication and computation time of a program and their effects on performance. Also available are CXLISP, a parallel version of the XLISP interpreter; GRAFIX, some graphics routines for the EGA and CGA; and a general execution profiler for determining execution time spent by program subroutines. PC-CUBE provides a programming environment similar to all hypercube systems running CrOS III, Mercury and CUBIX. In addition, every node (personal computer) has its own graphics display monitor and storage devices. These allow data to be displayed or stored at every processor, which has much instructional value and enables easier debugging of applications. Some application programs which are taken from the book Solving Problems on Concurrent Processors (Fox 88) were implemented with graphics enhancement on PC-CUBE. The applications range from solving the Mandelbrot set, Laplace equation, wave equation, long range force interaction, to WaTor, an ecological simulation
Analysing end-user energy rescheduling intentions using signal detection theory
AbstractTwo interfaces, co-created by designers and people living in eco-villages, were tested for their effects on end-user energy-use rescheduling intentions. When analysed with Signal Detection Theory both interfaces were implicated in biased user responses, but in opposite directions. Despite some favourable behavioural effects the majority of the 75 respondents chose not to reschedule their energy-use behaviours no matter what interface was displayed. The paper provides a demonstration of the role of behavioural factors in the apparently simple task of providing more information to energy-users on the assumption behaviour will change
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