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1.
High user interaction capability of mobile devices can help improve the accuracy of mobile visual search systems. At query time, it is possible to capture multiple views of an object from different viewing angles and at different scales with the mobile device camera to obtain richer information about the object compared to a single view and hence return more accurate results. Motivated by this, we propose a new multi-view visual query model on multi-view object image databases for mobile visual search. Multi-view images of objects acquired by the mobile clients are processed and local features are sent to a server, which combines the query image representations with early/late fusion methods and returns the query results. We performed a comprehensive analysis of early and late fusion approaches using various similarity functions, on an existing single view and a new multi-view object image database. The experimental results show that multi-view search provides significantly better retrieval accuracy compared to traditional single view search.  相似文献   
2.
A general synthesis procedure is given for a versatile signal flow graph realization of a general transfer function by using current differencing buffered amplifier (CDBA). The proposed configuration uses n+1 CDBAs, n capacitors and at most 2n+4 resistors. This number of resistors can be reduced to n+1 for special cases. The circuit is eligible to obtain a variety of transfer characteristics with the same common denominator polynomial, and it is easily converted to different modes of operations. It is straightforward to find the values of the passive elements from the coefficients of the transfer function to be realized. Simulations results are obtained by using commercially available active component AD844 and CMOS technology as well. All of these make the proposed circuit attractive.  相似文献   
3.
How to design the pilot tones that are used in channel estimation has a significant effect on the estimation performance. To achieve good performance in least square (LS) algorithm, we propose the artificial bee colony (ABC) algorithm for optimizing the placement of pilot tones in MIMO–OFDM systems. We also derive the upper bound of mean square error of LS estimation with the help of Gerschgorin disc theorem for fitness function of ABC algorithm. The results show that designing pilot tones using the ABC algorithm outperforms other considered placement strategies in terms of high system performance and low computational complexity.  相似文献   
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In this study, temperature distribution in a CCD coated piston used in an HCCI engine was investigated and was guided by existing experimental results. A model based on experimental observations obtained from the experiments at Shell research center was developed by using finite element technique to investigate 3D thermal analyses for both clean and deposited piston. Effect of the CCD thickness on the temperature distribution was analyzed by comparing the results from the clean piston and deposited one. It was observed that the deposited surface temperature increases with increasing the thickness in a decreasing rate. Both aluminum and steel piston compared with each other in respect to the maximum temperature for the same CCD thicknesses, which were tn = 9 and tm = 30 in micro meters. Compared to the clean piston, maximum temperature on the top surface of the aluminum and steel metals diminish 6 °C and 9 °C respectively, because of CCD's relatively low heat transfer coefficient.  相似文献   
7.
In this article, a general all‐pole current transfer function synthesis procedure using current backward transconductance amplifiers (CBTAs) is proposed. The proposed configuration uses n current backward transconductance amplifiers and n grounded capacitors as the only type of passive elements. The circuit is eligible to realize any all‐pole transfer characteristics with a given strictly Hurwitz (stable) denominator polynomial. Further, it is straightforward to find the values of the passive elements from the coefficients of this polynomial by using the Routh–Hurwitz algorithm as in the realization of a two‐element kind passive network synthesis. In this sense and as far as the author's knowledge, it is the only active structure that can be synthesized like a passive two‐element kind Cauer circuit. The simulations that are performed using PSPICE exhibit satisfactory results coherent with the theory. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
8.
Determination of biogenic amines in sucuk   总被引:1,自引:0,他引:1  
The biogenic amines content of sucuk (Turkish dry fermented sausage) were determined on 30 samples obtained from retail markets and butchers in Turkey. Also, pH and aw values, microbiological properties, and NPN levels of these samples were analyzed. The most important biogenic amines were tyramine (range 2.4–676 mg/kg), followed by putrescine varied from not detected to 364 mg/kg. Histamine content was under 50 mg/kg in 80% of the samples while it was over 100 mg/kg in only one sample. Tryptamine was detected in 16 of 30 samples in the range of 1.2–82.3 mg/kg.

Lactic acid bacteria, Micrococcus/Staphylococcus and Enterobacteriaceae counts of samples varied from 2.84 to 8.85 log cfu/g, <2.00 to 6.74 log cfu/g, and <2.00 to 5.04 log cfu/g, respectively. pH values were varied between 4.53 and 6.29 while water activity (aw) were measured to be between 0.761 and 0.960. NPN values were determined to be between 1.47% and 4.10%. Generally, total amine content was high in samples that had high NPN levels.  相似文献   

9.
The effects of probiotics (Lactobacillus acidophilus and Bifidobacterium lactis), packaging (vacuum, 50% N2 + 50% CO2 or 100% CO2), storage temperature (4 and 10 °C) and storage time (90 d) on lipid oxidation, colour and microbial properties of sliced dry fermented sausage ‘sucuk’, which has a long storage time at low temperatures, was investigated. Probiotic‐added samples showed a significant reduction in the thiobarbituric acid‐reactive substances (TBARS) values compared with a control and starter culture groups. The analysis showed that control groups had the highest pH and that the pH was not affected by packaging or storage temperature. Probiotic use had a significant effect on total aerobic bacteria, lactic acid bacteria and Micrococcus/Staphylococcus counts, and bacterial counts decreased with storage time. The Enterobacteriaceae count was below detectable levels (<2.00 CFU g−1) throughout the storage period. The storage temperatures had no effect on the microbial counts. Packaging had a significant effect on lactic acid bacteria, and the highest value was determined with 50% N2 + 50% CO2. The addition of probiotics and the storage time resulted in a significant decrease of colour values (L*, a* and b*). Copyright © 2005 Society of Chemical Industry  相似文献   
10.
Eukaryotic elongation factor 2 (eEF-2) can undergo ADP-ribosylation in the absence of diphtheria toxin. The binding of free ADP-ribose and endogenous transferase-dependent ADP-ribosylation were distinct reactions for eEF-2, as indicated by different findings. Incubation of eEF-2 tryptic fragment 32/33 kDa (32F) with NAD was ADP-ribosylated and gave rise to the covalent binding of ADP-ribose to eEF-2. 32F was revealed to be at the C-terminal by Edman degradation sequence analysis. In our study, the elution of 32F from SDS-PAGE was ADP-ribosylated both in the presence and absence of diphtheria toxin. These results suggest that endogenous ADP-ribosylation of 32F might be related to protein synthesis. This modification appears to be important for the cell function.  相似文献   
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