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31.
Wake M. Bossert R. Carson J. Coulter K. Delchamps S. Gourlay S. Jaffery T.S. Kinney W. Koska W. Lamm M.J. Strait J. Sims R. Winters M. 《IEEE transactions on magnetics》1992,28(1):141-144
The quench behaviors of 10 model dipole magnets for the Superconducting Super Collider (SSC) have been studied. Horizontally split yoke, vertically split yoke, and the latest 50 mm diameter design were compared with regard to the quench characteristics. The excitation results showed a good progress of the R&D program. SSC magnets can now be built with no training to the required field of 6.65 T at 4.3 K 相似文献
32.
The odd-skipped (odd) gene, which was identified on the basis of a pair-rule segmentation phenotype in mutant embryos, is initially expressed in the Drosophila embryo in seven pair-rule stripes, but later exhibits a segment polarity-like pattern for which no phenotypic correlate is apparent. We have molecularly characterized two embryonically expressed odd-cognate genes, sob and bowel (bowl), that encode proteins with highly conserved C2H2 zinc fingers. While the Sob and Bowl proteins each contain five tandem fingers, the Odd protein lacks a fifth (C-terminal) finger and is also less conserved among the four common fingers. Reminiscent of many segmentation gene paralogues, the closely linked odd and sob genes are expressed during embryogenesis in similar striped patterns; in contrast, the less-tightly linked bowl gene is expressed in a distinctly different pattern at the termini of the early embryo. Although our results indicate that odd and sob are more likely than bowl to share overlapping developmental roles, some functional divergence between the Odd and Sob proteins is suggested by the absence of homology outside the zinc fingers, and also by amino acid substitutions in the Odd zinc fingers at positions that appear to be constrained in Sob and Bowl 相似文献
33.
The objective of this study is to study the pharmacokinetics of imipenem-cilastatin in patients with anuria related to multiorgan failure during continuous venovenous hemodialysis (CVVHD) at a fixed blood flow rate of 60 ml/min, fixed dialysate flow rate of 20 ml/min, and drainage flow rate of 1-3 mil/min. A prospective open label study was designed in an intensive care unit in a university hospital. Six patients who required mechanical ventilation and inotropic agents and exhibited acute anuric renal failure were examined. Intravenous imipenem-cilastatin, 500/500 mg, was administered over 30 mins. Blood samples were obtained from the inlet and the outlet of the dialyzer and dialysate samples from the outlet before and at 0.0, 0.5, 1.0, 2.0, 3.0, 6.0, 9.0, and 12.0 hrs after infusion ended. The peak and trough concentrations of imipenem were 32.47 +/- 6.69 micrograms/ml and 1.12 +/- 0.46 micrograms/ml, respectively, whereas those of cilastatin were 50.05 micrograms/ml +/- 14.80 and 9.53 +/- 3.25 micrograms/ml, respectively. The half life was 2.79 +/- 0.3 hr for imipenem, and 6.67 +/- 0.93 hr for cilastatin. Total body clearance of imipenem was 89.4 +/- 17.5 ml/min, including the clearance by CVVHD of 18.7 +/- 1.2 ml/min, and corresponding values for cilastatin were 31.7 +/- 9.0 ml/min and 13.7 +/- 3.4 ml/min. In conclusion, in patients with anuria, the elimination of imipenem-cilastatin was constant during CVVHD. The recommended regimen in patients with anuria who receive CVVHD in this setting was estimated as intravenous imipenem-cilastatin, 500/500 mg, every 12 hrs. 相似文献
34.
Improvements in computer-aided design (CAD) tools can significantly increase designer productivity, since the ability to explore a variety of possible designs quickly and effectively is essential for a designer. Using an optimization tool, systematic exploration of design spaces can be achieved readily. The general goal of the work presented here is to aid design by combining the strengths of optimization techniques with those of CAD systems. The specific objective of this paper is to introduce goal directed geometry (GDG) as a computational framework for parametric design, aiding the formulation of engineering problems with geometric considerations and their solution with a multi-objective optimization package. Using GDG, What if questions can be posed and answered in a systematic fashion. Specific issues to be addressed include the development of a general parametric design problem formulation, development of static and dynamic geometric non-interference constraints for use in this formulation, and investigation of the efficacy of the adaptive linear programming (ALP) multiobjective optimization algorithm in solving such problems. Two examples are presented, one each to illustrate the use of the static and dynamic non-interference constraints. Results demonstrate that the GDG formulation can be applied readily to a wide variety of parametric design problems. Additionally, the ALP algorithm successfully navigates around geometric constraints, although care must be taken when linearizing highly non-linear design spaces. 相似文献
35.
Improving quality of software product line by analysing inconsistencies in feature models using an ontological rule‐based approach 下载免费PDF全文
In software product line engineering, feature models (FMs) represent the variability and commonality of a family of software products. The development of FMs may introduce inaccurate feature relationships. These relationships may cause various types of defects such as inconsistencies, which deteriorate the quality of software products. Several researchers have worked on the identification of defects due to inconsistency in FMs, but only a few of them have explained their causes. In this paper, FM is transformed to predicate‐based feature model ontology using Prolog. Further, first‐order logic is employed for defining rules to identify defects due to inconsistency, the explanations for their causes, and suggestions for their corrections. The proposed approach is explained using an FM available in Software Product Line Online Tools repository. It is validated using 26 FMs of discrete sizes up to 5,543 features, generated using the FeatureIDE tool and real‐world FMs. Results indicate that the proposed methodology is effective, accurate, and scalable and improves software product line. 相似文献
36.
Caitlin L. Lippitt Douglas A. Stow Dar A. Roberts Lloyd L. Coulter 《International journal of remote sensing》2018,39(3):655-683
Identifying habitats that should be protected from further disturbance or conversion and isolating high-risk areas is a focus of community habitat plans in southern California shrublands. Larger wildfires are occurring at shorter intervals in recent decades, contributing to degradation and conversion of shrubland vegetation. Multitemporal remote-sensing approaches can bridge the gap between vegetation mapping and field sampling in habitats where frequent quantification and mapping of vegetation growth forms over large extents is required. The objective of this study is to examine the reliability and stability of a multiple endmember spectral mixture analysis (MESMA) approach with moderate spatial resolution imagery for monitoring changes in growth form fractional cover in shrubland habitats. Estimates from visual interpretation of high spatial resolution image were used as reference data for validating MESMA-derived maps and as basis for providing complementary monitoring protocols that may be accurate and cost-effective across multiple scales. Growth form proportions modelled in burned and unburned management areas compare well with expected fractional cover in mature and regenerating shrublands. In the management areas recovering from fire, herbaceous cover fraction exceeded 0.40 for all three study dates, suggesting that large portions of those management areas may already be invaded. From 2008 to 2011 overall herbaceous cover fraction in shrubland area increased by 2%. Herbaceous cover fraction was modelled with an overall mean absolute error (MAE) of 0.08, a smaller percentage than the percentage of herbaceous cover change recorded in areas recovering from fire (increase in herbaceous cover fraction from 0.09 to 0.13). This MESMA approach would be effective for quantifying changes in fractional cover that exceed 0.10, providing a way to delineate and quantify herbaceous invasions and expansions following disturbance or succession. 相似文献
37.
H. David Coulter 《Microscopy research and technique》1986,4(4):315-328
A freezing apparatus has been developed for bringing blocks of tissue into contact with a block of sapphire chilled to 17°K. A toggle linkage minimizes rebound by slowing the rate of approach of the tissue to the cold surface to a velocity of zero. A glove box limits condensation on the surface of the sapphire, and a miniature moist chamber protects the specimen from drying and premature freezing. About 50 blocks of tissue can be frozen in an hour and a half by using 5 liters of liquid helium. The tissue is then frozendried at controlled temperature, fixed with OsO4 vapor, and infiltrated with epoxy resin in a simple bench-top freeze-drier without breaking vacuum. About two-thirds of the blocks are useful for electron microscopy. Brain tissue frozen and dried by using these methods retains enough immunoreactivity for enkephalin in plastic sections to permit its detection with immunohistochemistry by using both the light microscope (with immunofluorescence) and the electron microscope (with colloidal gold). 相似文献
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39.
Well‐defined multiarmed star random and block copolymers of ε‐caprolactone with l ‐lactide with controlled molecular weights, low polydispersities, and precise numbers of arms were synthesized by the ring‐opening polymerization of respective cyclic ester monomers. The polymers were characterized by 1H‐NMR and 13C‐NMR to determine their chemical composition, molecular structure, degree of randomness, and proof of block copolymer formation. Gel permeation chromatography was used to establish the degree of branching. Star‐branched random copolymers exhibited lower glass‐transition temperatures (Tg's) compared to a linear random copolymer. When the star random copolymers were melt‐blended with poly(l ‐lactic acid) (PLA), we observed that the elongation of the blend increased with the number of arms of the copolymer. Six‐armed block copolymers, which exhibited higher Tg's, caused the maximum improvement in elongation. In all cases, improvements in the elongation were achieved with no loss of stiffness in the PLA blends. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43267. 相似文献