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91.
Young-Woo Lee Byong-Hun Ahn 《Engineering Management, IEEE Transactions on》1991,38(3):237-244
A hierarchical weapon systems valuation model framework is discussed and the applicability of the analytic hierarchy process (AHP) in establishing relative values of military weapon systems is investigated. The model is a modified version of the weapon effectiveness index/weighted unit value method (WEI/WUV), a conventional method of static valuation of ground weapon systems as well as a combat unit's force potential. The hierarchical structures gives some unique features to the application of AHP. A calibration study for the model with AHP-based pairwise comparisons has been conducted for some weapon systems in Korea. Its results confirm the applicability and practicality of the 1-9 scale AHP by group judgments in measuring the relative values of weapons 相似文献
92.
93.
Antimicrobial susceptibility and coagulase gene typing of Staphylococcus aureus isolated from bovine clinical mastitis cases in Turkey 总被引:1,自引:0,他引:1
The objectives of this study were to determine antimicrobial resistance patterns of Staphylococcus aureus strains isolated from bovine clinical mastitis cases and to subtype the strains by polymerase chain reaction (PCR) technique based on coagulase gene polymorphism. Two hundred sixty-five S. aureus isolates collected from individual animals in different herds (n = 235) from 1995 to 2004 were tested for susceptibility to penicillin, ampicillin, amoxicillin-clavulanate, oxacillin, oxytetracycline, enrofloxacin, kanamycin-cephalexin, and trimethoprim-sulfamethoxazole using the agar disc diffusion test. Strains were also tested for β-lactamase production. A total of 29.8% of the strains were susceptible to all antimicrobial agents tested. The highest resistance was observed in 63.3% of the strains against β-lactam antibiotics, penicillin and ampicillin. Oxytetracycline resistance was observed in 27.9% of the strains, either alone or in combination with β-lactams. No resistance was detected for amoxicillin-clavulanate, oxacillin, enrofloxacin and kanamycin-cephalexin. β-Lactamase production and resistance to β-lactam antibiotics were usually correlated. Resistance against β-lactams increased from 43.5% in 1995 to 58 to 77% from 1999 to 2004.One hundred twenty-five strains were examined for coagulase gene polymorphism. The isolates were subtyped into 4 types by coagulase gene-based PCR. A predominant 1000-bp PCR product was observed in 60.8% of the isolates typed. The results indicate that a few coagulase gene types of S. aureus are responsible for the majority of bovine clinical mastitis cases in one province of Central Anatolia region, Turkey. 相似文献
94.
Kyoung Soo Yook Soon Ok Jeon Chul Woong Joo Jun Yeob Lee Myung Seop Kim Hong Seok Choi Seok Jong Lee Chang-Wook Han Yoon Heung Tak 《Organic Electronics》2009,10(4):681-685
A high efficiency pure white phosphorescent organic light-emitting diode was developed by combining a deep blue emitting phosphorescent dopant material with red/green phosphorescent emitting materials. A simple stack structure of blue/red:green was used and tris((3,5-difluoro-4-cyanophenyl)pyridine) iridium was used as a deep blue emitting phosphorescent dopant. A pure white emission with a color coordinate of (0.29, 0.31) and a very high current efficiency of 28 cd/A was obtained after managing the device architecture of the all phosphorescent white devices. 相似文献
95.
The device performances of spin-coated and stamp transfer printed devices were compared. There was little difference of morphology between the spin-coated and stamp transfer printed devices. However, the stamp transfer printing process was better than the spin-coating process in terms of current density, light-emitting efficiency and lifetime. In particular, the lifetime of the stamp transfer printed device was doubled compared with that of the spin-coated device. 相似文献
96.
Soon Ok Jeon Kyoung Soo Yook Chul Woong Joo Hyo Suk Son Sang Eok Jang Jun Yeob Lee 《Organic Electronics》2009,10(5):998-1000
High efficiency red phosphorescent organic light-emitting diodes have been developed using a spirobenzofluorene type phosphine oxide (SPPO2) as a host material. The SPPO2 had a high glass transition temperature of 119 °C and a smooth surface morphology with a surface roughness less than 1 nm. The red device with the SPPO2 as a host showed a quantum efficiency of 14.3% with a current efficiency of 20.4 cd/A. 相似文献
97.
Hong Kyoon Choi Mun Ho Kim Sang Hyuk Im O Ok Park 《Advanced functional materials》2009,19(10):1594-1600
Hexagonally arrayed structures of colloidal crystals with uniform surface are a good candidate for master molds to be used in soft lithography. Here, the fabrication of periodically arrayed nanostructures using poly(dimethylsiloxane) (PDMS) molds based on three‐dimensionally (3D) ordered colloidal crystals is reported. A robust, high‐quality 3D colloidal‐crystal master molds is prepared using the colloidal suspension containing a water‐soluble polymer. The surface patterns of the 3D colloidal crystals can then be transferred onto a polymer film via soft lithography, by means of the replication of the surface pattern with PDMS. Various hexagonally arrayed nanostructure patterns can be fabricated, including close‐packed and non‐close‐packed 2D arrays and honeycomb structures by the structural modification of the 3D colloidal‐crystal templates. The replicated hexagonally arrayed structures can also be used as templates for producing colloidal crystals with 2D superlattices. 相似文献
98.
Young-Ok Park Keon-Wang Lee Young-Woo Rhee 《Journal of Industrial and Engineering Chemistry》2009,15(1):36-39
The CuMnOx catalysts were deep coated into polysulfonamide felts by vacuum suction to simultaneously remove the particulate and nitrogen oxides. This filter consists of a high temperature foam layer as a surface layer, a catalytic pleated felt as a medium layer and glassfiber fabric layer with high temperature phenol resin as a final layer. In this study, the effects of catalyst loading on the pleated felt, operating temperature on nitrogen oxides reduction with NH3 were mainly investigated. Tests were conducted at operating temperature range from 150 to 250 °C and at face velocity of 1 m/min. Within these ranges, NO removal efficiency was over 90% at the catalyst loading of 350 g/m2 and 200 °C. 相似文献
99.
100.
Chang HW Sung Y Kim KH Nam YD Roh SW Kim MS Jeon CO Bae JW 《Environmental science & technology》2008,42(16):6058-6064
A crucial problem in the use of previously developed genome-probing microarrays (GPM) has been the inability to use uncultivated bacterial genomes to take advantage of the high sensitivity and specificity of GPM in microbial detection and monitoring. We show here a method, digital multiple displacement amplification (MDA), to amplify and analyze various genomes obtained from single uncultivated bacterial cells. We used 15 genomes from key microbes involved in dichloromethane (DCM)-dechlorinating enrichment as microarray probes to uncover the bacterial population dynamics of samples without PCR amplification. Genomic DNA amplified from single cells originating from uncultured bacteria with 80.3-99.4% similarity to 16S rRNA genes of cultivated bacteria. The digital MDA-GPM method successfully monitored the dynamics of DCM-dechlorinating communities from different phases of enrichment status. Without a priori knowledge of microbial diversity, the digital MDA-GPM method could be designed to monitor most microbial populations in a given environmental sample. 相似文献