271.
The Research on Improved Iterative Control Algorithm for Maximum Entropy Model in Electronic Technology
Yongqin, Wei; Yinjing, Guo; Na, Wu ...
Advances in Mechanical and Electronic Engineering
Book Chapter
In the distributed processing, where common labeled data may be not available for designing classifier ensemble, however, an ensemble solution is necessary, traditional fixed decision aggregation ...
could not account for class prior mismatch or classifier dependencies in electronic technology. Previous transductive learning strategies have several drawbacks, e.g., feasibility of the constraints was not guaranteed and heuristic learning was applied. We overcome these problems by developing improved iterative scaling (IIS) algorithm for optimal solution. This method is shown to achieve improved decision accuracy over the earlier approaches in electronic technology.
več
272.
New polymer syntheses. CIX. Biodegradable, alternating copolyesters of terephthalic acid, aliphatic dicarboxylic acids, and alkane diols
Shaik, Abbas-Ali; Richter, Martin; Kricheldorf, Hans R. ...
Journal of polymer science. Part A, Polymer chemistry,
1 October 2001, Letnik:
39, Številka:
19
Journal Article
Copolyesters with an alternating sequence of terephthalic acid and aliphatic dicarboxylic acids were prepared with three different methods. First, dicarboxylic acid dichlorides were reacted with ...
bis(2‐hydroxyethyl)terephthalate (BHET) in refluxing 1,2‐dichlorobenzene. Second, the same monomers were polycondensed at 0–20 °C in the presence of pyridine. Third, dicarboxylic acid dichlorides and silylated BHET were polycondensed in bulk. Only this third method gave satisfactory molecular weights. Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry revealed that the copolyesters prepared by the pyridine and silyl methods might have contained considerable fractions of cyclic oligoesters and polyesters despite the absence of transesterification and backbiting processes. The alternating sequences and thermal properties were characterized with 1H NMR spectroscopy and differential scanning calorimetry measurements, respectively. In agreement with the alternating sequence, all copolyesters proved to be crystalline, but the crystallization was extremely slow slower than that of poly(ethylene terephthalate). A second series of alternating copolyesters was prepared by the polycondensation of silylated bis(4‐hydroxybut‐ yl)terephthalate with various aliphatic dicarboxylic acid dichlorides. The resulting copolyesters showed significantly higher rates of crystallization, and the melting temperatures were higher than those of the BHET‐based copolyesters. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3371–3382, 2001
Biodegradable polyesters with an alternating sequence of terephthalic acid, aliphatic dicarboxylic acids, and aliphatic diols were prepared with three different methods and characterized with respect to their chemical structures and thermal properties.
več
Dostopno za:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
273.
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