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31.
Pınar Duygulu Volkan Atalay 《International Journal on Document Analysis and Recognition》2002,5(1):17-27
In this paper, we present a logical representation for form documents to be used for identification and retrieval. A hierarchical
structure is proposed to represent the structure of a form by using lines and the XY-tree approach. The approach is top-down
and no domain knowledge such as the preprinted data or filled-in data is used. Geometrical modifications and slight variations
are handled by this representation. Logically identical forms are associated to the same or similar hierarchical structure.
Identification and the retrieval of similar forms are performed by computing the edit distances between the generated trees.
Received: August 21, 2001 / Accepted: November 5, 2001 相似文献
32.
H. Huseyin Ozturk 《国际能源研究杂志》2005,29(10):937-944
This paper presents an experimental determination of energy requirement for greenhouse heating. The overall heat loss coefficient, heat input, the control factor for air‐tightness, the rate of heat loss and the thermal screen effectiveness were calculated. The relationships between the overall heat loss coefficient and the wind speed, and the outside temperature were modelled, including the measured and calculated values. It was found that the thermal screen effectiveness was 16 and 19.8% for the polyethylene (PE) and polyester screens, respectively. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
33.
This paper is concerned with the static and dynamic bifurcation phenomena exhibited by a nonlinear autonomous system in the vicinity of a double-zero eigenvalue. It is demonstrated analytically that such a coincident critical point is often located on the intersection of the divergence and flutter boundaries of the system. The analysis is performed via a new 'unification technique' which is based on an intrinsic perturbation procedure. The new approach is capable of yielding information about stability of solutions as well as incipient and secondary bifurcations. Indeed, the stability properties of the system and secondary Hopf bifurcations are discussed conveniently, and explicit results concerning post-critical solutions are presented. An illustrative example is analysed. 相似文献
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36.
Saricimen Huseyin Kahraman Ramazan Malaibari Zuhair Abdur Rauf Md. 《Protection of Metals and Physical Chemistry of Surfaces》2018,54(5):926-933
Protection of Metals and Physical Chemistry of Surfaces - The objective of this study was to characterize the surfaces of the steel products produced locally during their exposure to the industrial... 相似文献
37.
Electrospun nylon 6,6 nanofibers functionalized with cyclodextrins for removal of toluene vapor 下载免费PDF全文
Functional nylon 6,6 nanofibers incorporating cyclodextrins (CD) were developed via electrospinning. Enhanced thermal stability of the nylon 6,6/CD nanofibers was observed due to interaction between CD and nylon 6,6. X‐ray photoelectron spectroscopy and attenuated total reflectance Fourier transform infrared spectroscopy studies indicated the existence of some CD molecules on the surface of the nanofibers. Electrospun nylon 6,6 nanofibers without having CD were ineffective for entrapment of toluene vapor from the environment, whereas nylon 6,6/CD nanofibrous membranes can effectively entrap toluene vapor from the surrounding by taking advantage of the high surface‐volume ratio of nanofibers with the added advantage of inclusion complexation capability of CD presenting on the nanofiber surface. The modeling studies for formation of inclusion complex between CD and toluene were also performed by using ab initio techniques. Our results suggest that nylon 6,6/CD nanofibrous membranes may have potential to be used as air filters for the removal of organic vapor waste from surroundings. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41941. 相似文献
38.
Huseyin Cankaya Reyhane Kilci Alphan Sennaroglu Emel Yilgor Iskender Yilgor 《应用聚合物科学杂志》2010,117(1):378-383
Novel, polymeric UV‐to‐visible converters were prepared by doping elastomeric poly(ether‐urethaneurea) copolymers with 5–25% by weight of ErCl3 6H2O, corresponding to Er3+ concentrations of 2.19 to 10.86% by weight. When excited in the UV at 355 nm, the doped films generated a very broad, continuous visible luminescence between 400 and 750 nm. Preparation and spectroscopic characterization of the samples are discussed in detail. The color coordinates, color temperature, color rendering index of the samples, and the degree of overlap of their emission bands with the spectral response of the eye were determined. The color rendering index of samples is in the 57–70 range. The sample containing 2.19% by weight of Er3+ was found to give the color coordinates closest to the white‐source region and the highest color rendering index. The color temperatures of the samples were in the 5093–5540 K range. Overlap between the emission bands and the spectral response of the eye improved with increasing erbium concentration. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
39.
Ferhat Yücedag Cigdem Atalay‐Oral Sibel Erkal Ahmet Sirkecioglu Djursun Karasartova Fikret Sahin Serife Birgül Tantekin‐Ersolmaz Fatma Seniha Güner 《应用聚合物科学杂志》2010,115(3):1347-1357
As an alternative to petroleum‐based polyol, hydroxyl containing material was prepared from linseed oil for polyurethane synthesis. Hexamethylene di‐isocyanate (HMDI) and/or 4, 4′‐methylene diphenyl di‐isocyanate (MDI) were used as isocyanate source. The polymerization reaction was carried out without catalyst. Polymer films were prepared by casting‐evaporation technique. The MDI/HMDI‐based polyurethane and its films had higher Tg and better thermal property than that of the HMDI‐based one because of the existence of benzene ring in the polymer chain. Static water contact angle was determined to be 74° and 77.5° for HMDI and MDI/HMDI‐based films, respectively. Water adsorption was found to be around 2.6–3.6% for both films. In vitro degradation of polyurethanes in phosphate buffered saline at 37°C was investigated by gravimetric method. Fourier transform infrared spectroscopy and scanning electron microscopy were used for confirmation of degradation on the polymer surface. The degradation rate of the HMDI‐based polyurethane film was found higher than that of the MDI/HMDI‐based film. Both the direct contact method and the MMT test were applied for determination of cytotoxicity of polymer films, and the polyurethane films investigated here was not cytotoxic. Silver‐containing films were prepared using Biocera A® as filler and were screened for their antibacterial performance against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and/or Bacillus subtilis. The films prepared with and without Biocera A® exhibited antibacterial activity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
40.
Medine Güllüce Münevver Skmen Fikrettin ahin Atalay Skmen Ahmet Adigüzel Hakan
zer 《Journal of the science of food and agriculture》2004,84(7):735-741
The in vitro antimicrobial and antioxidant activities of the essential oil and methanolic extract of Micromeria fruticosa ssp serpyllifolia as well as the composition of the essential oil were examined. The essential oil exhibited activity against 14 bacteria, three fungi and a yeast, with minimal inhibitory concentration (MIC) values ranging from 31.25 to 125 µl ml?1, whilst the methanolic extract was inactive. Antioxidant activity was measured by two methods, namely scavenging of the free radical DPPH and inhibition of linoleic acid oxidation. The methanolic extract exhibited significant antioxidant activity in both assays, providing 50% inhibition at 70.9 ± 0.5 µg ml?1 concentration in the DPPH assay and inhibiting linoleic acid oxidation to 59% at 2 mg ml?1 concentration, whilst the essential oil showed activity only at higher concentrations. The gallic acid equivalent total phenolic content of the methanolic extract was found to be 55.2 ± 2.00 µg mg?1 dry weight extract (5.5% w/w). The chemical composition of the hydrodistilled essential oil was analysed by means of GC/MS. Twenty‐nine constituents were identified, the main ones being piperitenone (50.61%) and pulegone (29.19%). Copyright © 2004 Society of Chemical Industry 相似文献