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101.
C.F. Cheung W.B. Lee W.M. Wang Y. Wang W.M. Yeung 《Expert systems with applications》2011,38(5):5245-5258
Management of unstructured information, such as emails, is vital for supporting knowledge work in professional services. However, the conventional way for managing unstructured information is inadequate as the knowledge work and associated tasks are becoming more complex, are dynamically changing with time and involve multiple concepts. This paper attempts to address the inadequacy, deficiency and limitations of the methods presently used to elicit knowledge from masses of unstructured information. These methods rely heavily on manpower, are time consuming and costly. With the development of a multi-faceted and automatic knowledge elicitation system (MAKES) manpower, time and cost can be dramatically reduced. The MAKES integrates the processes of collecting data, classifying unstructured information, modelling knowledge flow and social network analysis, and makes all of these actions into a connected process to audit unstructured information automatically. This audit is based on specific search criteria, search keywords, and the user behaviours of the knowledge workers. The unstructured information is automatically organized, classified and presented in a multi-facet taxonomy map. New concepts and knowledge are uncovered, analyzed and updated continuously from the incoming unstructured information, using a purpose-built knowledge elicitation algorithm named self-associated concept mapping (SACM). The capability and advantages of the MAKES are demonstrated through a successful trial implementation and a verification test conducted in an electronics trading company. Encouraging results have been achieved and a number of potential advantages have been realized. The area of application in this first deployment is based on an email-intensive organization and the proposed study will contribute to the advancement of methods and tools for managing other kinds of unstructured information. 相似文献
102.
A circuit that, combined with one or two commercially available digital signal processing (DSP) chips, may implement all voice-band modem standards from 300 b/s to 14.4 kb/s, in full or half duplex operation including echo-cancelling standards, is presented. All analog functions and all non-DSP digital functions are performed by the circuit. Good dynamic range with low distortion in the analog circuitry is maintained while designing for a high-density digital process with high-quality capacitors. Such a process can be used to achieve an area-efficient circuit. The circuit has been implemented in a 1.2-μm CMOS double-poly, double-metal process, operates off a single 5-V supply, and measures only 63 kmil2 (40.7 mm2) 相似文献
103.
Mammalian 'regulators of G protein signaling' (RGS proteins) help shut off G-protein-mediated signaling by GTPase activation. But new evidence shows that RGS proteins can also speed up the activation of signaling. The combined effect is a change in signaling kinetics without a decrease in signaling intensity. 相似文献
104.
105.
An objective method for the assessment of levelness of dyed materials has been established. The relative unlevelness index developed takes account of the coefficients of variation of reflectance measured over the visible spectrum, with appropriate consideration of human vision sensitivity. It was found that the index demonstrated good correlation with the visual levelness assessment. 相似文献
106.
Inward rectifier K+ channels control the cell's membrane potential and neuronal excitability. We report that the IRK3 but not the IRK1 inward rectifier K+ channel activity is inhibited by m1 muscarinic acetylcholine receptor. This m1 modulation cannot be accounted for by protein kinase C, Ca2+, or channel phosphorylation, but can be mimicked by Mg2+. Based on quantitative analyses of IRK3 and two different IRK1 mutant channels bestowed with sensitivity to m1 modulation, we suggest that the resting Mg2+ level causes chronic inhibition of IRK3 channels, and m1 receptor stimulation may lead to an increase of cytoplasmic Mg2+ concentration and further channel inhibition, due to the ability of Mg2+ to lead these channels into a prolonged inactivated state. 相似文献
107.
Genghis Khan (Gek) as a putative effector for Drosophila Cdc42 and regulator of actin polymerization
The small GTPases Cdc42 and Rac regulate a variety of biological processes, including actin polymerization, cell proliferation, and JNK/mitogen-activated protein kinase activation, conceivably via distinct effectors. Whereas the effector for mitogen-activated protein kinase activation appears to be p65PAK, the identity of effector(s) for actin polymerization remains unclear. We have found a putative effector for Drosophila Cdc42, Genghis Khan (Gek), which binds to Dcdc42 in a GTP-dependent and effector domain-dependent manner. Gek contains a predicted serine/threonine kinase catalytic domain that is 63% identical to human myotonic dystrophy protein kinase and has protein kinase activities. It also possesses a large coiled-coil domain, a putative phorbol ester binding domain, a pleckstrin homology domain, and a Cdc42 binding consensus sequence that is required for its binding to Dcdc42. To study the in vivo function of gek, we generated mutations in the Drosophila gek locus. Egg chambers homozygous for gek mutations exhibit abnormal accumulation of F-actin and are defective in producing fertilized eggs. These phenotypes can be rescued by a wild-type gek transgene. Our results suggest that this multidomain protein kinase is an effector for the regulation of actin polymerization by Cdc42. 相似文献
108.
SR Kleeberger RC Levitt LY Zhang M Longphre J Harkema A Jedlicka SM Eleff D DiSilvestre KJ Holroyd 《Canadian Metallurgical Quarterly》1997,17(4):475-478
Through a survey of all departments of pediatrics, neurology and neuropathology in Germany, we calculated the incidence of all major forms of leukodystrophy. Only diagnoses based on specific biochemical tests in association with typical findings and/or neuroradiologically proven white matter involvement were accepted. In accordance with these strict criteria, 617 cases of leukodystrophy were found (incidence of all forms: app. 2.0/100,000). Minimal incidence was estimated at 0.8/100,000 for adrenoleukodystrophy/adrenomyeloneuropathy (ALD/AMN), 0.6/100,000 for metachromatic leukodystrophy (MLD), and 0.6/100,000 for Krabbe disease. Thus ALD/AMN is apparently underdiagnosed in Germany. A considerable proportion of leukodystrophies could not be classified in spite of adequate diagnostic procedures in experienced centers. 相似文献
109.
110.
CC Szeto CC Chow GT Ko KY Li VT Yeung CS Cockram 《Canadian Metallurgical Quarterly》1997,73(855):39-40
A 22-year-old Chinese man, a HBsAg carrier, presented with relapse of thyrotoxic Graves' disease complicated by thrombocytopenia and hepatitis. Platelet count and liver enzymes gradually improved following successful treatment of the thyrotoxicosis with radioactive iodine. Possible pathogenetic links and therapeutic implications are discussed. 相似文献