1000 resultados para Efficient stabilizer


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While Histograms of Oriented Gradients (HOG) plus Support Vector Machine (SVM) (HOG+SVM) is the most successful human detection algorithm, it is time-consuming. This paper proposes two ways to deal with this problem. One way is to reuse the features in blocks to construct the HOG features for intersecting detection windows. Another way is to utilize sub-cell based interpolation to efficiently compute the HOG features for each block. The combination of the two ways results in significant increase in detecting humans-more than five times better. To evaluate the proposed method, we have established a top-view human database. Experimental results on the top-view database and the well-known INRIA data set have demonstrated the effectiveness and efficiency of the proposed method. (C) 2010 Elsevier B.V. All rights reserved.

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A facile and efficient one-pot synthesis of substituted cyclophosphamidic chlorides and their analogues has been developed from readily available enaminones, 2-arylamino-3-acetyl-5,6-dihydro4H-pyrans.

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A faccile and efficient one-pot synthesis of highly substituted thiophenes has been developed and employed for the preparation of a small focused library. Treatment of 1,3-dicarbonyl compounds 1 with CS2 in the presence of K2CO3 in DMF at room temperature, followed by stepwise addition of alkyl bromides 2 and methylene active bromides 3, provided via intramolecular cyclization 2,3,4,5-tetrasubstituted thiophenes 4 in yields of 77-94%. This protocol, combining construction and modification of the thiophene ring, increases the structural diversity of final products from readily available materials. A mechanism for the one-pot synthesis of thiophenes of type 4 has been proposed. A small focused library of thiophenes is prepared using the sequential addition of reagents to achieve unique substitution in the 2 and 5 position of the thiophene ring

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A facile and efficient one-pot synthesis of polysubstituted pyridin-2(1H)-ones from a variety of beta-oxo amides under Vilsmeier conditions is described, and a mechanism involving sequential halogenation, formylation and intramolecular nucleophilic cyclization is proposed

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Efficient and divergent one-pot synthesis of fully substituted 1H-pyrazoles and isoxazoles from cyclopropyl oximes based on reaction conditions selection is reported. Under Vilsmeier conditions (POCl3/DMF), substituted 1H-pyrazoles were synthesized from 1-carbamoyl, 1-oximyl cyclopropanes via sequential ring-opening, chlorovinylation, and intramolecular aza-cyclization. In the presence of POCl3/CH2Cl2, substituted isoxazoles were obtained from the cyclopropyl oximes via ring-opening and intramolecular nucleophilic vinylic substitution (SNV) reactions

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A facile and efficient synthesis of substituted alpha-alkylidene-beta-lactams have been developed via a NaOH-promoted intramolecular aza-Michael addition of alpha-carbamoyl, alpha-(1-chlorovinyl) ketene-S,S-acetals and subsequent nucleophilic vinylic substitution (SNV) reaction in alcoholic aqueous media. (C) 2008 Elsevier Ltd. All rights reserved.

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Nanocrystalline Tm3+-doped La2O3 phosphors were prepared through a Pechini-type sol-gel process. X-ray diffraction, field-emission scanning electron microscopy, photoluminescence, and cathodoluminescence spectra were utilized to characterize the synthesized phosphors. Under the excitation of UV light (234 nm) and low-voltage electron beams (1-3 kV), the Tm3+-doped La2O3 phosphors show the characteristic emissions of Tm3+(D-1(2), (1)G(4)-F-3(4), H-3(6) transitions).

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A bipolar transport compound, 2,5-bis(4-(9-(2-ethylhexyl)-9H-carbazol-3-yl) phenyl)-1,3,4-oxadiazole (CzOXD), incorporating both electron-and hole-transport functionalities, was synthesized and fully characterized by H-1 NMR, C-13 NMR, elemental analysis and mass spectrometry. Its thermal, electrochemical, electronic absorption and photoluminescent properties were studied

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The efficiencies of red organic light-emitting diode (OLED) using tris-(8-hydroxy-quinoline)aluminum (Alq(3)) as host and 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) as dopant were greatly increased by adding a small amount (0.3 wt%) of Ir compound, iridium(III) bis(3-(2-benzothiazolyl)-7-(diethylamino)-2H-1-benzopyran-2-onato-N-',C-4) (acetyl acetonate) (Ir(C6)(2)(acac)), as a sensitizer

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Characteristics of white organic light-emitting devices based on phosphor sensitized fluorescence are improved by using a multiple-emissive-layer structure, in which a phosphorescent blue emissive layer is sandwiched between red and green&yellow ones. In this device, bis[(4,6-difluorophenyl)-pyridinato-N,C-2] (picolinato), bis(2,4-diphenyl-quinoline) iridium (III) acetylanetonate, fac bis (2-phenylpyridine) iridium, and 5,6,11,12-tetraphenylnaphthacene are used as blue, red, green, and yellow emitters, respectively.

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We report a high molar extinction coefficient organic sensitizer for high efficiency dye-sensitized solar cells. In combination with a solvent-free ionic liquid electrolyte, we have demonstrated a similar to 7% cell showing an excellent stability measured under the thermal and light soaking dual stress. This is expected to have an important practical consequence on the production of flexible, low-cost, and lightweight DSC based on plastic matrix.

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An efficient O-arylation of phenols and aliphatic alcohols with aryl halides was developed that uses an air-stable copper(I) complex as the catalyst. This arylation reaction can be performed in good yield in the absence of Cs2CO3. A variety of functional groups are compatible with these reaction conditions with low catalyst loading levels.

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A convenient and efficient synthesis of substituted dihydrofurans is developed via ring-enlargement of 1-dimethylaminopropenoyl-1-carbamoyl/benzoyl cycloproparres catalyzed by ammonium acetate in acetic acid with high regio- and stereoselectivity. Some of the newly synthesized substituted dihydrofurans are subjected to further synthetic transformation in the presence of NaOH (aq) in ethanol to afford the corresponding 5-aryl-2,3-dihydrofuro[3,2-c]pyfidin-4(5H)-ones in high yields.

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A facile and efficient one-pot synthesis of halogenated pyridin-2(1H)-ones from a series of readily available enaminones under Vilsmeier conditions is described, and a mechanism involving sequential halogenation, formylation, and intramolecular nucleophilic cyclization is proposed.