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931.
Hirofumi Fukuyama Jens Leth Hougaard Kazuyuki Sekitani Jianming Shi 《The Journal of the Operational Research Society》2016,67(1):9-19
We investigate the basic monotonicity properties of least-distance (in)efficiency measures on the class of non-convex FDH (free disposable hull) technologies. We show that any known FDH least-distance measure violates strong monotonicity over the strongly (Pareto-Koopmans) efficient frontier. Taking this result into account, we develop a new class of FDH least-distance measures that satisfy strong monotonicity and show that the developed (in)efficiency measurement framework has a natural profit interpretation. 相似文献
932.
Shinji Sakai Tetsu Yamaguchi Ryan Anugrah Putra Rie Watanabe Masaaki Kawabe Masahito Taya Koei Kawakami 《Journal of Sol-Gel Science and Technology》2012,61(2):374-380
Electrospun ultrafine silica fibers were calcined at 150–800 °C. The relation of calcination temperature to the ability to
form biomimetic apatite in a simulated body fluid solution (SBF) was evaluated. The largest apatite particles, formed on non-calcined
fibers after 1 week of soaking in SBF, were 10 μm in diameter, had a narrow size distribution (coefficient of variation 9%),
and were similar to pearls on string. The particles size decreased with increasing calcination temperature below 250 °C and
the particles formed on the fibers calcined at 250 °C were 4.5 μm in diameter. No particles were found on those calcined above
500 °C. By using a concentrated SBF at 1.5-times higher ionic concentrations than SBF, the size of apatite microparticles
increased about 50%. The fibrous substrate covered with apatite particles was effective for osteoblastic differentiation of
pre-osteoblastic cells. 相似文献
933.
Dr. Akira Fusano Shuhei Sumino Satoshi Nishitani Takaya Inouye Keisuke Morimoto Dr. Takahide Fukuyama Prof. Ilhyong Ryu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(30):9415-9422
The atom‐transfer carbonylation reaction of various alkyl iodides thereby leading to carboxylic acid esters was effectively accelerated by the addition of transition‐metal catalysts under photoirradiation conditions. By using a combined Pd/hν reaction system, vicinal C‐functionalization of alkenes was attained in which α‐substituted iodoalkanes, alkenes, carbon monoxide, and alcohols were coupled to give functionalized esters. When alkenyl alcohols were used as acceptor alkenes, three‐component coupling reactions, which were accompanied by intramolecular esterification, proceeded to give lactones. Pd‐dimer complex [Pd2(CNMe)6][PF6]2, which is known to undergo homolysis under photoirradiation conditions, worked quite well as a catalyst in these three‐ or four‐component coupling reactions. In this metal/radical hybrid system, both Pd radicals and acyl radicals are key players and a stereochemical study confirmed the carbonylation step proceeded through a radical carbonylation mechanism. 相似文献
934.
This paper describes the traveling tournament problem, a well-known benchmark problem in the field of tournament timetabling.
We propose a new lower bound for the traveling tournament problem, and construct a randomized approximation algorithm yielding
a feasible solution whose approximation ratio is less than 2+(9/4)/(n−1), where n is the number of teams. Additionally, we propose a deterministic approximation algorithm with the same approximation ratio
using a derandomization technique. For the traveling tournament problem, the proposed algorithms are the first approximation
algorithms with a constant approximation ratio, which is less than 2+3/4. 相似文献
935.
Katusi Fukuyama 《Monatshefte für Mathematik》2013,171(1):33-63
The law of the iterated logarithm for discrepancies of {θ k x} is proved for θ < ?1. When θ is not a power root of rational number, the limsup equals to 1/2. When θ is an odd degree power root of rational number, the limsup constants for ordinary discrepancy and star discrepancy are not identical. 相似文献
936.
937.
Atsuyuki Sorimachi Shinji Tokonami Yasutaka Omori Tetsuo Ishikawa 《Radiation measurements》2012,47(6):438-442
This paper describes how humidity, wind and ambient aerosols in air influence the detection responses of passive detectors. Two types of alpha track detectors based on a passive radon (222Rn)–thoron (220Rn) discriminative measurement technique were used: the Raduet and Radopot detectors that were developed and calibrated by the National Institute of Radiological Sciences, Japan. The initial experiment showed that the infiltration rate of 220Rn onto sponges with a high air exchange rate for the Raduet detectors was one third lower than that onto filters for the Radopot detectors. Little distinct dependence on humidity was observed for the 222Rn detection responses of both detectors. For 220Rn, the detection responses of both detectors for the high air exchange rate seemed to decrease slightly at high humidity conditions. The 220Rn detection responses of the Radopot detectors had little influence from wind speed. The 220Rn detection responses of the Raduet detectors for the high air exchange rate seemed to decrease at low wind speeds. Furthermore, there was little difference between the detection responses in the presence and absence of ambient aerosol particles because the ambient aerosols were filtered out during their passive diffusion through the sponges and filters for the Raduet and Radopot detectors, respectively. 相似文献
938.
939.
Shunsuke Takahashi Shohei Kawasaki Koji Yamaguchi Hidefumi Miyata Hirofumi Kurita Takeshi Mizuno Shun-ichi Matsuura Akira Mizuno Masahiko Oshige Shinji Katsura 《Journal of fluorescence》2013,23(4):635-640
We developed two labeling methods for the direct observation of single-stranded DNA (ssDNA), using a ssDNA binding protein and a ssDNA recognition peptide. The first approach involved protein fusion between the 70-kDa ssDNA-binding domain of replication protein A and enhanced yellow fluorescent protein (RPA-YFP). The second method used the ssDNA binding peptide of Escherichia coli RecA labeled with Atto488 (ssBP-488; Atto488-IRMKIGVMFGNPETTTGGNALKFY). The labeled ssλDNA molecules were visualized over time in micro-flow channels. We report substantially different dynamics between these two labeling methods. When ssλDNA molecules were labeled with RPA-YFP, terminally bound fusion proteins were sheared from the free ends of the ssλDNA molecules unless 25-mer oligonucleotides were annealed to the free ends. RPA-YFP-ssλDNA complexes were dissociated by the addition of 0.2 M NaCl, although complex reassembly was possible with injection of additional RPA-YFP. In contrast to the flexible dynamics of RPA-YFP-ssλDNA complexes, the ssBP-488-ssλDNA complexes behaved as rigid rods and were not dissociated even in 2 M NaCl. 相似文献
940.
Shinji Kawsaki Fujio Okino Hidekazu Touhara 《Molecular Crystals and Liquid Crystals》2013,570(1):629-633
Abstract In situ x-ray diffraction experiments of the fluorinated fullerenes, C60F x (x = 0, 36 and 48) at high temperatures have been undertaken. The structural phase transformation of C60F48 was observed at about 358 K. It was also found that the lattice parameters of the low temperature phase of C60F48 show anomalous change at about 310 K. The thermal expansion coefficients of the fluorinated fullerenes were determined by using the change of the lattice parameters with temperature. 相似文献