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991.
Unattended fingerprint identification systems need to reject input attempts by a replica. Previously, we proposed detecting the color changes of a finger during an input action as a signature of liveliness. To improve its reliability, a dual-LED imaging system is investigated. It employs two LEDs with peak emissions at 530 and 630 nm to cover the spectral ranges where live fingers show characteristic changes. Using nine types of replicas and the live fingers of 42 participants, we have recorded and analyzed 153 input trials. The two groups of data are successfully separated by some defined criteria. 相似文献
992.
A new surface profiling algorithm called the local model fitting (LMF) method is proposed. LMF is a single-shot method that employs only a single image, so it is fast and robust against vibration. LMF does not require a conventional assumption of smoothness of the target surface in a band-limit sense, but we instead assume that the target surface is locally constant. This enables us to recover sharp edges on the surface. LMF employs only local image data, so objects covered with heterogeneous materials can also be measured. The LMF algorithm is simple to implement and is efficient in computation. Experimental results showed that the proposed LMF method works very well. 相似文献
993.
Shuji Kijima Masashi Kiyomi Yoshio Okamoto Takeaki Uno 《Theoretical computer science》2010,411(26-28):2591-2601
We discuss the problems to list, sample, and count the chordal graphs with edge constraints. The objects we look at are chordal graphs sandwiched by a given pair of graphs where we assume that at least one of the input graphs is chordal. The setting is a natural generalization of chordal completions and deletions. For the listing problem, we give an efficient algorithm running in polynomial time per output with polynomial space. As for the sampling problem, we give two clues that indicate that a random sampling is not easy. The first clue is that we show #P-completeness results for counting problems. The second clue is that we give an instance for which a natural Markov chain suffers from an exponential mixing time. These results provide a unified viewpoint from algorithms’ theory to problems arising from various areas such as statistics, data mining, and numerical computation. 相似文献
994.
995.
Natural killer (NK) T cells are well known to play important roles in both tumor rejection and the defense against infectious. Therefore, the antitumor potential of NKT cell-activating antigens have been the focus for the development of NKT cell-based immunotherapies. Up to now, several studies have revealed that the administrations of glycolipids (e.g. α-galactosylceramide) can successfully treat certain metastatic tumors. However, liver injuries appeared upon the application of these antigens. We previously examined the potential of using β-glucosylceramide (β-GlcCer) to inhibit tumor metastasis to the liver. The aim of this study was to determine the antimetastatic effects of β-GlcCer and its impact on the activation of NKT cells. Intraperitoneal administration of β-GlcCer enhanced the production of interferon-γ from hepatic lymphocytes containing NKT cells, and increased the cytotoxicity of hepatic lymphocytes against tumor cells. Moreover, β-GlcCer administration suppressed the hepatic metastasis of tumors in wild type (WT) mice, but not in CD1d (-/-) or Jα18 (-/-) mice. The drawback associated with the other glycolipids in liver injury was not noted in WT mice treated with the continuous daily administration of β-GlcCer for 2 weeks. The present study demonstrated that β-GlcCer treatment activates invariant NKT cells, thus resulting in the inhibition of tumor metastasis. 相似文献
996.
Plant‐derived 3‐deoxyanthocyanidins are photochromic materials that are coloured under ultraviolet (UV) irradiation and decoloured under light‐shielded storage. In this study, the optimised solvent composition is investigated to enhance the photochromic performance of luteolinidin, a 3‐deoxyanthocyanidin derivative. The visible absorbance ratio between the solution after UV irradiation and after storage in the dark, an index of photochromic performance, was found to be affected by the pH of the solution, and the value reached a maximum when the pH of the solution was 5.7. The type of organic solvent, which is necessary to dissolve luteolinidin, also affected the photochromic performance. When diethylene glycol or dipropylene glycol was used, the value of the absorbance ratio was especially large. Furthermore, this optimised solvent composition displayed excellent photochromic properties with an extract from the sorghum grain shell containing a large amount of 3‐deoxyanthocyanins. 相似文献
997.
Ryo Ohtani Masashi Arai Akihiro Hori Masaki Takata Shinji Kitao Makoto Seto Susumu Kitagawa Masaaki Ohba 《Journal of Inorganic and Organometallic Polymers and Materials》2013,23(1):104-110
Three porous coordination polymers {Fe(dpa)[Pt(CN)4]·G·nH2O} (1-G; dpa = 1,2-di(4-pyridyl)ethane, G = dpa, bibenzyl (bbz) and stilbene (stb)) have been prepared by using a long and flexible ligand dpa. These compounds formed analogous 3-D elongated Hofmann-type frameworks based on 2-D planar layers extended by Pt–CN–Fe linkages with dpa as flexible pillar ligands. 1-dpa showed a characteristic three-step spin transition (ST) in the temperature range 180–240 K. The ST behavior was reversibly modulated by dehydration and hydration processes in keeping with the three steps. 1-bbz and 1-stb exhibited a gradual three-step ST over the range 80–200 K and an abrupt ST with T c = 163 K. The guest-dependent cooperativity of the ST behavior is discussed by considering the flexibility of the framework and guest molecules. 相似文献
998.
Masashi Iwata 《Korean Journal of Chemical Engineering》2000,17(5):574-578
A novel technique utilizing the gelation reaction of natural polymers has been proposed for the separation of solid from liquid in difficult-to-filter colloidal suspensions. This technique is especially effective in the treatment of colloidal muddy water of high solid concentration, which is often produced as a byproduct of certain construction processes. Colloidal suspensions are mixed with a sodium alginate solution, and this mixture is added to a calcium chloride solution, resulting in the entrapping of colloidal particles by the calcium alginate gel. Gel suspensions are then drained gravitationally, followed by mechanical expression of gel particles. Fundamental aspects of this process are investigated by using sodium bentonite as an experimental material. The alginate-bentonite mixture is added dropwise to the calcium solution. Decreasing the droplet size of the mixture expedites gelation since the diffusion of calcium ions into droplets determines the rate of gelation reactions. Reducing the alginate content expedites expression of the gel since alginate content is inversely proportional to the rate of expression. 相似文献
999.
Toshihiko Yamagishi Hiroshi Akiyama Shinichi Kimura Masashi Toyoda 《Journal of the American Oil Chemists' Society》1989,66(12):1801-1808
The following describes the quantitative determining method for phosphatidylcholine (PC) using the HPLC-RI system which we
have developed. It uses Lichromsorb, Si 60 (10 μm), 4.6 mm × 250 mm as the column and a mobile phase consisting of n-hexane/isopropanol/water
=1:4:1. In this report, we compared data from selected high-purity (60–100 wt%) samples using the HPLC-RI, HPLC-UV and conventional
TLC-P methods.
Under the conditions we described, the HPLC-UV method was somewhat affected by fatty acid compositions. As a result, there
were some inconsistencies in the measured values. However, the HPLC-RI method we propose was applicable to PC from both egg
yolk and soybeans. In addition, the HPLC-RI method produced data which correlated well with data from the TLC-P method, and
this data was highly accurate and exhibited satisfac-tory reproductibility. 相似文献
1000.
Tsuguo Yamaoka Masashi Nishiki Ken'Ichi Koseki Mitsunobu Koshiba 《Polymer Engineering and Science》1989,29(13):856-858
A novel positive resist was prepared by sensitizing poly(p-trimethylsilyloxystyrene) with p-nitro-benzyl-9, 10-diethoxyanthracene-2-sulfonate (NBAS) which was found to be a deep UV bleachable acid precursor. The silylated polymer is converted to alkaline soluble poly(p-hydroxy-styrene) in the presence of acid and a small amount of water. The photoresist gives high resolution positive patterns on imagewise exposure with deep UV light with a sensitivity of 15 mJ/cm2. 相似文献