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801.
802.
Digant Gupta Christopher G Lis Sadie L Dahlk Jessica King Pankaj G Vashi James F Grutsch Carolyn A Lammersfeld 《Nutrition journal》2008,7(1):19
Background
Bioelectrical Impedance (BIA) derived phase angle is increasingly being used as an objective indicator of nutritional status in advanced cancer. Subjective Global Assessment (SGA) is a subjective method of nutritional status. The objective of this study was to investigate the association between BIA derived phase angle and SGA in advanced colorectal cancer. 相似文献803.
Song Xiao-chun Huang Song-ling Zhao Wei 《Russian Journal of Nondestructive Testing》2007,43(5):326-331
Magnetization is the key to inspection of a tank floor via the magnetic-flux-leakage (MFL) technique. In order to optimize
the magnetic circuit of the MFL detector and obtain the best detection effects, the influences of the magnet size on the floor
magnetization condition, the gap magnetic flux density, and the magnetic force were studied with the help of the finite element
method (FEM) and the effects of some other parameters, such as the magnet pole spacing and pole-piece thickness, on the signal-to-noise
ratio were analyzed. The simulation results indicate that variation of the magnet width affects the magnetization much more
than variation of the magnet thickness and that the detector can reach a trade-off between the magnetization effects and the
driving force when the magnet is about 30 mm thick and 40 mm wide. On condition that the floor has reached its magnetizing
saturation, an increase in the magnet-pole spacing and the pole-piece thickness can improve the testing sensitivity and the
signal-to-noise ratio.
The text was submitted by the authors in English. 相似文献
804.
Cloning of observables, unlike standard cloning of states, aims at copying the information encoded in the statistics of a
class of observables rather then on quantum states themselves. In such a process the emphasis is on the quantum operation
(evolution plus measurement) necessary to retrieve the original information. We analyze, for qubit systems, the cloning of
a class generated by two noncommuting observables, elucidating the relationship between such a process and joint measurements.
This helps in establishing an optimality criterion for cloning of observables. We see that, even if the cloning machine is
designed to act on the whole class generated by two noncommuting observables, the same optimal performances of a joint measurement
can be attained. Finally, the connection with state dependent cloning is enlightened. 相似文献
805.
806.
Zusammenfassung Dieser Artikel beschreibt einige Erfahrungen und typische Problemstellungen mit Textmining in der Medizin und gibt einen Einblick
in aktuelle und zukünftige Herausforderungen in Forschung & Entwicklung. Interessant ist n?mlich, dass auch im ,,Multimedia-Zeitalter“
die meiste Information immer noch als ,,Text“ vorliegt. Mithilfe von statistischen und linguistischen Verfahren wird mit sogenannter
,,Textmining-Software“ versucht, aus Freitexten Information ,,heraus zu schürfen“ (deshalb ,,Textmining“). Allerdings ist
es damit noch nicht genug. Der n?chste Schritt besteht darin, die Information sowohl nutzbar als auch brauchbar zu machen.
Die jeweiligen End-Benutzerinnen und End-Benutzer müssen in die Lage versetzt werden, auf der Basis der gewonnenen Information
deren Wissen zu erweitern. In unserem konkreten Fall sollen damit Entscheidungen im Rahmen ?rztlichen Handelns unterstützt
werden. Probleml?sungen in diesem Bereich erfordern eine holistische Sicht- und Herangehensweise. Daher wird es immer wichtiger,
Erkenntnisse aus Informatik und Psychologie zusammenflie?en zu lassen und auf systemischer Ebene technologisch umzusetzen. 相似文献
807.
Shiue-Lung Chen Shui-Jinn Wang Kai-Ming Uang Tron-Min Chen Wei-Chi Lee Bor-Wen Liou 《Photonics Technology Letters, IEEE》2007,19(6):351-353
Through the use of selective nickel (Ni) electroplating, patterned laser liftoff technique, and surface roughing of the top n-GaN epilayer, a novel process for the fabrication of vertical-structured metal-substrate GaN-based light-emitting diodes (VM-LEDs) to avoid difficulties in Ni substrate dicing and improve device yield was proposed and demonstrated. In conjunction with a sidewall passivation with SiO2 and keeping the size of epilayer smaller than that of Ni island, a considerable improvement in yield and device performance were shown. As compared to conventional lateral-structured GaN-based LEDs, VM-LEDs show an increase in light output power about 174% at 350 mA with a significant decrease in forward voltage from 3.5 to 3.17 V 相似文献
808.
根据高性混凝土的水化特性、物理力学特性及自收缩特性,分析了高性能混凝土早期开裂机理和影响早期开裂的主要因素.并结合工程实例,借助混凝土温度和应力有限元仿真计算方法分析研究了表面适度保温和水管冷却技术在高性能混凝土温控防裂中的应用效果.研究结果表明,表面适度保温与水管冷却相结合能有效降低混凝土的内外温差,减小混凝土早期表面拉应力与后期内部拉应力,防裂效果明显,对类似的工程具有借鉴作用. 相似文献
809.
Junwei Fu Zhengbiao Zhang Zhenping Cheng Jian Zhu Wei Zhang Xiulin Zhu 《Polymer Bulletin》2008,61(3):287-297
A novel reversible addition-fragmentation chain transfer (RAFT) reagent bearing triphenylamine (TPA)
group, 4-diphenylamino-dithiobenzoic acid benzyl ester (DDABE), was designed and synthesized. It was used
in the RAFT polymerizations of styrene (St) and methyl acrylate (MA) to prepare end-functionalized polymers.
The results of the polymerization showed that the RAFT polymerizations could be well controlled using DDABE
as the RAFT agent. Number-average molecular weight (Mn,GPC) increased linearly
with monomer conversion, and molecular weight distributions were relatively narrow (PDI<
1.50). The results of chain-extension reaction, 1H NMR spectra and UV/Vis
spectra confirmed that most of the polymers chains were end-capped by the functional triphenylamine
(TPA) groups. The effect of feed molar ratios of St/DDABE/AIBN on polymerization was investigated. 相似文献
810.
The cellulose solvent dimethyl sulfoxide (DMSO)/tetrabutylammonium fluoride trihydrate (TBAF) was
successfully applied as reaction medium for the synthesis of allyl cellulose by conversion of the polymer
with allyl chloride in the presence of solid NaOH. Samples with degree of substitution from 0.50 to 2.98
were accessible by varying the molar ratio anhydroglucose unit:allyl chloride:NaOH and reaction time. DMSO/TBAF
was found to be an efficient reaction medium for the preparation of highly functionalized samples from spruce
sulfite pulp with degree of polymerization of about 500 even in a scale of 50 g. The allyl cellulose samples
were characterized by means of FTIR- and NMR spectroscopy. Size exclusion chromatography revealed negligible
polymer degradation during synthesis and purification of the samples. 相似文献