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81.
The effects of treatment of commercial prepress-solvent extracted and direct-solvent extracted cottonseed mares with several chemical agents and solvents were studied. The analytical results for “free” and “total” gossypol of the finished meals show that treatment with aliphatic amines, followed by extraction with a suitable solvent, removed large proportions of the “free” as well as “bound” gossypol. This reduction of “free” and “bound” gossypol was accompanied, in some experiments, by an increase in the nitrogen solubility and available lysine, as compared with the results obtained with the untreated air-dried marcs. The available lysine contents of the treated mares was significnatly correlated with the nitrogen solubility in 0.02N aqueous NaOH. One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.  相似文献   
82.
The reuse of scientific knowledge obtained from one investigation in another investigation is basic to the advance of science. Scientific investigations should therefore be recorded in ways that promote the reuse of the knowledge they generate. The use of logical formalisms to describe scientific knowledge has potential advantages in facilitating such reuse. Here, we propose a formal framework for using logical formalisms to promote reuse. We demonstrate the utility of this framework by using it in a worked example from biology: demonstrating cycles of investigation formalization [F] and reuse [R] to generate new knowledge. We first used logic to formally describe a Robot scientist investigation into yeast (Saccharomyces cerevisiae) functional genomics [f1]. With Robot scientists, unlike human scientists, the production of comprehensive metadata about their investigations is a natural by-product of the way they work. We then demonstrated how this formalism enabled the reuse of the research in investigating yeast phenotypes [r1 = R(f1)]. This investigation found that the removal of non-essential enzymes generally resulted in enhanced growth. The phenotype investigation was then formally described using the same logical formalism as the functional genomics investigation [f2 = F(r1)]. We then demonstrated how this formalism enabled the reuse of the phenotype investigation to investigate yeast systems-biology modelling [r2 = R(f2)]. This investigation found that yeast flux-balance analysis models fail to predict the observed changes in growth. Finally, the systems biology investigation was formalized for reuse in future investigations [f3 = F(r2)]. These cycles of reuse are a model for the general reuse of scientific knowledge.  相似文献   
83.
CSIRO has recently developed a real-time roof monitoring system for underground coal mines and successfully tried the system in gate roads at Ulan Mine. The system integrated displacement monitoring, stress monitoring and seismic monitoring in one package. It included GEL multianchor extensometers, vibrating wire uniaxial stress meters, ESG seismic monitoring system with microseismic sensors and high-frequency AE sensors. The monitoring system automated and the data can be automatically collected by a central computer located in an underground nonhazardous area. The data are then transferred to the surface via an optical fiber cable. The real-time data were accessed at any location with an Internet connection. The trials of the system in two tailgates at Ulan Mine demonstrate that the system is effective for monitoring the behavior and stability of roadways during longwall mining. The continuous roof displacement/stress data show clear precursors of roof falls. The seismic data (event count and locations) provide insights into the roof failure process during roof fall.  相似文献   
84.
85.
The purpose of this work is to predict elastic and thermodynamic properties of chromium-based alloys based on first-principles calculations and to demonstrate an appropriate computational approach to develop new materials for high-temperature applications in energy systems. In this study, Poisson ratio is used as a screening parameter to identify ductilizing additives to the refractory alloys. The results predict that elements such as Ti, V, Zr, Nb, Hf, and Ta show potential as ductilizers in Cr while Al, Ge, and Ga are predicted to decrease the ductility of Cr. Experimental evidence, where available, validates these predictions. The purpose of this work is to predict elastic and thermodynamic properties of chromium-based alloys based on first-principles calculations and to demonstrate an appropriate computational approach to develop new materials for high-temperature applications in energy systems. In this study, Poisson ratio is used as a screening parameter to identify ductilizing additives to the refractory alloys. The results predict that elements such as Ti, V, Zr, Nb, Hf, and Ta show potential as ductilizers in Cr while Al, Ge, and Ga are predicted to decrease the ductility of Cr. Experimental evidence, where available, validates these predictions.  相似文献   
86.
We have developed an automatic method to monitor the AVHRR instrument sensitivity over time in the short-wave reflective channels to ensure that trends in the data series obtained by this instrument are real and not sensor artefacts.Our radiometric calibration method uses the Multivariate Alteration Detection (MAD) algorithm to statistically select invariant features over land areas from multiple image-pairs that are compared to assess changes in the instrument's calibration. This method requires no a priori regional knowledge and is globally applicable. A calibrated time series from Pseudo-Invariant Features located in central Australia are shown to have long-term trends removed. The resulting MAD-based calibration has a root mean squared error of ∼ 5-6% for both channels 1 and 2 and is in alignment with other approaches.  相似文献   
87.
88.
While quality assessment is essential for testing, optimizing, benchmarking, monitoring, and inspecting related systems and services, it also plays an essential role in the design of virtually all visual signal processing and communication algorithms, as well as various related decision-making processes. In this pa-per, we first provide an overview of recently derived quality assessment approaches for traditional visual signals (i.e., 2D im-ages/videos), with highlights for new trends (such as machine learning approaches). On the other hand, with the ongoing development of devices and multimedia services, newly emerged visual signals (e.g., mobile/3D videos) are becoming more and more popular. This work focuses on recent progresses of quality metrics, which have been reviewed for the newly emerged forms of visual signals, which include scalable and mobile videos, High Dynamic Range (HDR) images, image segmentation results, 3D images/videos, and retargeted images.  相似文献   
89.
The question of whether stable, active metamaterials can be created is addressed, both through a discussion of absolute instability and an analysis of a transmission line that produces dispersion analogous to that of the familiar split-ring resonator/wire-based metamaterial. The gain is introduced using negative conductance diodes and it is shown that the frequency bandwidth controls the stability window. The diodes are located as lumped elements in the unit cell. It is demonstrated that the production of an, active, negative phase (left-handed) frequency window, with spatial amplification is possible. The paper then goes on to assume that since loss can be controlled in this way special types of solitons can be created from phase and loss compensation and they could be the basis of future computational devices. The candidates selected are diffraction-managed spatial solitons and their basic properties are displayed numerically.  相似文献   
90.
An online programming examination was used to assess undergraduates who had learned Java for two terms. The advantages are that the students are assessed on what they have to do in practice, rather than on their theoretical knowledge, and that the marking load on the examiner is drastically reduced. The style of question used and the results of the examination are analyzed.  相似文献   
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