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61.
Vision tracking has significant potential for tracking resources on large scale, congested construction sites, where a small number of cameras strategically placed around the site could replace hundreds of tracking tags. The correlation of vision tracking 2D positions from multiple views can provide the 3D position. However, there are many 2D vision trackers available in the literature, and little information is available on which one is most effective for construction applications. In this paper, a comparative study of various vision tracker categories is carried out, to identify which one is most effective in tracking construction resources. Testing parameters for evaluating categories of trackers are identified, and benefits and limitations of each category are presented. The most promising trackers are tested using a database of construction operations videos. The results indicate the effectiveness of each tracker in relation to each parameter of the test, and the most suitable tracker needed to research effective 3D vision trackers of construction resources. 相似文献
62.
63.
Siwoo Park Ki-Choon Choi Minghao Fang Yung Chul Lim Young-Mi Jeon Jeong-Chae Lee 《Food science and biotechnology》2011,20(4):1125-1131
This study used in vitro and in vivo experimental models to investigate the anti-inflammatory potential of the butanol fraction of red bean ethanol extract (BF-RBEE), which contains the biologically active molecule catechin-7-β-d-glucopyranoside. Treatment with BF-RBEE inhibited nitric oxide production in lipopolysaccharide (LPS)-stimulated macrophages through suppression of extracellular signalregulated kinase and IκBα activation. In an in vivo murine sepsis model, oral administration of BF-RBEE improved mouse survival. Specifically, the survival rate of mice injected with LPS was 0 and 40% in ICR and BALB/c mice, respectively, whereas the survival of mice co-treated with BF-RBEE was 100% in both mouse types. This increase in survival with the BF-RBEE administration was correlated with decreased tumor-necrosis factor-α and interferon-γ and increased interleukin-10. Oral administration of BF-RBEE also inhibited total and ovalbumin-specific IgE production in experimental mice. These results suggest the possible usefulness of red beans in the treatment of inflammatory diseases. 相似文献
64.
XIN Ying GONG WeiZhi & ZHANG JingYin Innopower Superconductor Cable Co. Ltd. E.Rongchang Rd. Longsheng Industrial Park Beijing Economic & Technological Development Area Beijing China 《中国科学:信息科学(英文版)》2010,(4)
A superconductor has zero resistance at the superconducting state. This unique property creates many exceptional phenomena, of which some are known and the others are not. Our experiments with multilayer high temperature superconductor (HTS) cable samples revealed a new phenomenon that alternating current had a tendency to flow in the inner and outer layers of the cables. We attribute the cause of this phenomenon to the electromagnetic interaction in an infinite electrical conductivity medium and term it su... 相似文献
65.
Jong-Yul Kim Kyeong-Jun MunHyung-Su Kim June Ho Park 《International Journal of Electrical Power & Energy Systems》2011,33(8):1457-1461
In recent studies, PSO algorithm is applied to solve OPF problem. However, population based optimization method requires higher computing time to find optimal point. This shortcoming is overcome by a straightforward parallelization of PSO algorithm. The developed parallel PSO algorithm is implemented on a PC-cluster system with 8 Intel Pentium IV 2 GHz processors. The proposed approach has been tested on the test systems. The results showed that computing time of parallelized PSO algorithm can be reduced by parallel processing without losing the quality of solution. 相似文献
66.
Chae-Seon Hong Hyeong-Ho Park Hyung-Ho Park Ho Jung Chang 《Journal of Electroceramics》2009,22(4):353-356
Low-temperature crystallized ZnO thin film was achieved by sol–gel process using zinc acetate dihydrate and 2-methoxyethanol
as starting precursor and solvent, respectively. Ag nanoparticles were prepared with uniform size at 4.4 nm by spontaneous
reduction method of Ag 2-ethylhexanoate in dimethyl sulfoxide (DMSO). The optical and electrical properties of ZnO thin films
containing various contents of Ag-nanoparticles were monitored. Light scattering and charge emission and scattering behaviors
of Ag nanoparticles in ZnO film were found. The incorporation of Ag nanoparticles into Al-doped ZnO film was also investigated.
The optical transmittance was not degraded but the increase of electrical sheet resistance was found. The effect of Al-dopant
on the transmittance and electrical sheet resistance of ZnO film was found too great to distinguish the positive effect of
the incorporation of Ag nanoparticles into Al-doped ZnO thin films. 相似文献
67.
Y W Park 《Journal of dairy science》1990,73(11):3059-3067
Thirty varieties of commercial goat milk cheeses collected from 13 manufacturers in 11 states of the US were evaluated. Concentration profiles of basic nutrients, major and trace minerals, their correlations, and mineral ratios in the caprine cheeses were determined to compare nutritional parameters among the varieties. Mean percentage of moisture, fat, protein, and ash for plain soft, semi-soft, hard, pepper, garlic, and herb cheeses were 59.8, 22.5, 18.9, 1.74; 43.2, 28.5, 26.2, 2.83; 27.4, 32.3, 25.4, 3.58; 57.3, 22.9, 21.6, 1.32; 64.3, 18.3, 16.7, 1.34; 59.1, 21.8, 17.3, 1.60, respectively. Ranges of mean concentrations (mg/100 g wet basis) of S, P, K, Mg, Ca, Na, Cl, Fe, Al, Mn, Cu, and Zn were: 2.00 to 8.05; 192 to 785; 7.03 to 103; 10.3 to 78.0; 57.1 to 1035; 225 to 924; 96.0 to 1260; .52 to 8.73; .47 to 22.1; .08 to .40; .44 to 1.32; .49 to 4.13, respectively. Twenty of the 30 varieties were very high or high moisture cheeses, which would suggest slow coagulation as the major mode of fabrication. Wide variations in the concentrations of P, K, Ca, Na, Cl, Fe, Al, and Zn were found among and within varieties of the cheeses. High concentrations and variations in Fe and Al in the cheeses indicate a significant possibility of uptake of these elements into the products during farmstead manufacturing processes. Percentage of moisture was negatively and significantly (P less than .05 or P less than .01) correlated with the concentrations of ash, fat, protein, and most of the minerals. Percentage of ash was positively and significantly correlated with the concentrations of macrominerals but negatively and less correlated with concentrations of Fe, Al, Mn, and Cu. The Na:K ratio was the highest of the five mineral ratios. Differences were significant for Ca:P, Ca:Mg, and Na:K ratios among the six types of goat cheese tested. 相似文献
68.
Young-Hwan You Cheol-Hee Park Dae-Ki Hong Sung-Jin Kang Kyeung-Hak Seo Jin-Woong Cho 《Communications Letters, IEEE》2003,7(4):159-161
In this letter, a multi-phased CDMA system employing a variable spreading gain (VSG) approach is proposed for high-rate applications, based on four algorithms for selecting a multi-code set. From simulation results, in addition to simple receiver structure thanks to level clipping, the multi-phased VSG CDMA system provides an high bit rate transmission, while maintaining an acceptable performance degradation. 相似文献
69.
A novel multifunctional transceiver for chip-to-chip optical interconnects operating at 2.5 Gbit/s is proposed, which shares a common block between a receiver and a transmitter. This transceiver provides four conversion functions - electrical-to-optical, optical-to-optical, optical-to-electrical, and electrical-to-electrical - depending on the selection switch on a single chip. The whole chip integrated in 0.18 /spl mu/m CMOS occupies an area measuring 0.82/spl times/0.82 mm/sup 2/. 相似文献
70.
Jongdeog Kim Quan Le Munseob Lee Hark Yoo Dong‐Soo Lee Chang‐Soo Park 《ETRI Journal》2009,31(5):622-624
This letter presents a compact 2.5 Gb/s burst‐mode receiver using the first reported monolithic amplifier IC developed with 0.25 …m SiGe BiCMOS technology. With optimum avalanche photodiode gain, the receiver module can obtain a fast response, high sensitivity and wide dynamic range, satisfying the overhead timing and various power specifications for a 2.5 Gb/s next‐generation passive optical network (PON), as well as a legacy 1.25 Gb/s PON in the upstream. 相似文献