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171.
Tabata S Iida K Kimura K Iwasaki Y Nakazato M Kamata K Hirokado M 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2008,49(2):100-105
Methods using high-performance liquid chromatography with fluorescence detection (HPLC-FL) and using liquid chromatography with tandem mass spectrometry (LC/MS/MS) were developed for simultaneous determination of ochratoxin A (OTA), ochratoxin B (OTB) and citrinin (CIT) in cereal, fruit, and coffee products. The samples were extracted with ethyl acetate under an acidic condition, and then cleaned up with liquid-liquid separation. The test solutions were analyzed by reverse-phase HPLC-FL and LC/MS/MS. Mass spectral acquisition was performed in positive ion mode by applying multiple reaction monitoring. The performances of both detectors were almost equivalent. The recoveries of OTA and OTB were 87-111%, and that of CIT were 70-88%. The limits of quantification (S/N> or =10) of OTA, OTB and CIT was 0.1 mug/kg or less. These methods were considered to be useful for the determination of the three mycotoxins at low levels (0.1 microg/kg). 相似文献
172.
Optimizing two-pass connected-component labeling algorithms 总被引:5,自引:0,他引:5
We present two optimization strategies to improve connected-component labeling algorithms. Taking together, they form an efficient
two-pass labeling algorithm that is fast and theoretically optimal. The first optimization strategy reduces the number of
neighboring pixels accessed through the use of a decision tree, and the second one streamlines the union-find algorithms used
to track equivalent labels. We show that the first strategy reduces the average number of neighbors accessed by a factor of
about 2. We prove our streamlined union-find algorithms have the same theoretical optimality as the more sophisticated ones
in literature. This result generalizes an earlier one on using union-find in labeling algorithms by Fiorio and Gustedt (Theor
Comput Sci 154(2):165–181, 1996). In tests, the new union-find algorithms improve a labeling algorithm by a factor of 4 or
more. Through analyses and experiments, we demonstrate that our new two-pass labeling algorithm scales linearly with the number
of pixels in the image, which is optimal in computational complexity theory. Furthermore, the new labeling algorithm outperforms
the published labeling algorithms irrespective of test platforms. In comparing with the fastest known labeling algorithm for
two-dimensional (2D) binary images called contour tracing algorithm, our new labeling algorithm is up to ten times faster
than the contour tracing program distributed by the original authors.
Kesheng Wu is a staff computer scientist at Lawrence Berkeley National Laboratory. His work primarily involves data management, data analyses and scientific computing. He is the lead developer of FastBit bitmap indexing software for searching over large datasets. He also led the development of a software package call TRLan, which computes eigenvalues of large symmetric matrices on parallel machines. He received a Ph.D. in computer science from the University of Minnesota, an M.S. in physics from the University of Wisconsin-Milwaukee, and a B.S. in physics from Nanjing University, China. His homepage on the web is . Ekow Otoo holds a B.Sc. degree in Electrical Engineering from the University of Science and Technology, Kumasi, Ghana, and a Ph.D. degree in Computer Science from McGill University, Montreal, Canada. From 1987 to 1999, he was a tenured faculty at Carleton University, Ottawa, Canada. He has served as a consultant to Bell Northern Research, and the GIS Division, Geomatics Canada. He is presently a consultant with Mathematical Sciences Research Institute, Ghana, and a staff scientist/engineer, LBNL, Berkeley. He is a member of the ACM and IEEE. His research interests include database management, data structures, algorithms, parallel and distributed computing. Kenji Suzuki received his Ph.D. degree from Nagoya University in 2001. In 2001, he joined Department of Radiology at University of Chicago. Since 2006, he has been Assistant Professor of Radiology, Medical Physics, and Cancer Research Center. His research interests include computer-aided diagnosis, machine learning, and pattern recognition. He published 110 papers including 45 journal papers. He has served as an associate editor for three journals and a referee for 17 journals. He received Paul Hodges Award, RSNA Certificate of Merit Awards, Cancer Research Foundation Young Investigator Award, and SPIE Honorable Mention Award. He is a Senior Member of IEEE. 相似文献
Kenji SuzukiEmail: |
Kesheng Wu is a staff computer scientist at Lawrence Berkeley National Laboratory. His work primarily involves data management, data analyses and scientific computing. He is the lead developer of FastBit bitmap indexing software for searching over large datasets. He also led the development of a software package call TRLan, which computes eigenvalues of large symmetric matrices on parallel machines. He received a Ph.D. in computer science from the University of Minnesota, an M.S. in physics from the University of Wisconsin-Milwaukee, and a B.S. in physics from Nanjing University, China. His homepage on the web is . Ekow Otoo holds a B.Sc. degree in Electrical Engineering from the University of Science and Technology, Kumasi, Ghana, and a Ph.D. degree in Computer Science from McGill University, Montreal, Canada. From 1987 to 1999, he was a tenured faculty at Carleton University, Ottawa, Canada. He has served as a consultant to Bell Northern Research, and the GIS Division, Geomatics Canada. He is presently a consultant with Mathematical Sciences Research Institute, Ghana, and a staff scientist/engineer, LBNL, Berkeley. He is a member of the ACM and IEEE. His research interests include database management, data structures, algorithms, parallel and distributed computing. Kenji Suzuki received his Ph.D. degree from Nagoya University in 2001. In 2001, he joined Department of Radiology at University of Chicago. Since 2006, he has been Assistant Professor of Radiology, Medical Physics, and Cancer Research Center. His research interests include computer-aided diagnosis, machine learning, and pattern recognition. He published 110 papers including 45 journal papers. He has served as an associate editor for three journals and a referee for 17 journals. He received Paul Hodges Award, RSNA Certificate of Merit Awards, Cancer Research Foundation Young Investigator Award, and SPIE Honorable Mention Award. He is a Senior Member of IEEE. 相似文献
173.
Kenji Goto Takuya Kawashima Nobuo Tanabe 《Solar Energy Materials & Solar Cells》2006,90(18-19):3251-3260
We developed new heat-resisting transparent conductive oxide (TCO) films with resistivity of 1.4×10−4 Ω cm, an optical transmittance of above 80% (at 550 nm) and heat-resisting temperature at above 600 °C. The TCO films consists of fluorine-doped tin oxide films coated on indium–tin oxide films. They were prepared by a spray pyrolysis deposition method on glass substrates. The 100×100 mm2 dye-sensitized solar cells (DSCs) were prepared with the TCO films. An energy conversion efficiency of the DSC was improved drastically in comparison to the case with conventional TCO films. 相似文献
174.
Thronsen Elisabeth Mørkeseth Hanne Marioara Calin D. Minakuchi Kazuhiro Katsumi Tetsuya Marthinsen Knut Matsuda Kenji Holmestad Randi 《Metallurgical and Materials Transactions A》2022,53(9):3296-3310
Metallurgical and Materials Transactions A - The effect of 0.03 and 0.08 at. pct Fe additions on the formation of secondary phases in an Al–1.1Mg–0.5Cu–0.3Si at. pct alloy was... 相似文献
175.
填充热丝激光窄间隙焊接的实验研究 总被引:2,自引:0,他引:2
将填充热丝应用到高光束质量、长焦距的光纤激光窄间隙焊接中,不锈钢母材通过激光加热,镍基焊丝通过电流加热,有效利用复合热源的优势,提高了焊丝过渡稳定性和熔覆效率。通过高速摄像机对送丝过程进行在线观察,分析工艺参数对焊丝过渡的影响。研究不锈钢和镍基合金异种金属窄间隙焊接接头的凝固组织,并对焊缝金属进行元素分布扫描。研究发现,由焊丝电流和送丝速度等工艺参数决定的送丝稳定性是影响填充热丝激光焊接质量的最主要因素。对于窄间隙焊接,采用与间隙宽度相当的离焦光斑激光热导焊,可形成较好的侧壁熔合,由熔融金属曲面和侧壁构成的激光反射是侧壁熔合的主要原因。焊缝冷却速度较快,焊缝金属的凝固组织呈明显的对生生长,在坡口侧壁附近其生长方向与侧壁近似垂直,焊缝不存在宏观偏析。在间隙底部直角处容易出现未熔合现象,采用底部圆弧过渡的U型坡口后,可较好地解决底部未熔合问题,获得了无宏观缺陷的焊接接头。 相似文献
176.
Carbon nanotubes (CNTs) were produced by laser ablation of a graphite composite target in argon and nitrogen ambient gas. To investigate the effect of nitrogen gas on CNTs formation, the plasma plume was examined using optical emission spectroscopy. The vibrational temperature of C2 molecules was estimated by fitting of a Swan band spectrum. The temperature in N2 ambient gas is lower than that in Ar ambient gas. In a nitrogen atmosphere, the spectrum intensity of C2 Swan band was enhanced and CN violet system was also observed. Soot collected in the reaction tube was observed using FE-SEM and TEM. The soot deposited in the nitrogen gas contained more bundled CNTs than those in Ar ambience. 相似文献
177.
Hiroaki Nakamura Naomichi Hatano Ryōen Shirasaki Naomi Hirayama Kenji Yonemitsu 《Journal of Electronic Materials》2011,40(5):601-605
We consider thermoelectric effects in a pseudo-one-dimensional electron gas (P1DEG) with a spin–orbit interaction (SOI). The
SOI splits the dispersion relation of the P1DEG into subbands with an energy gap. We find quantum oscillations in transport
coefficients, which coincide with the locations of the subband edges, as a function of the electrochemical potential. 相似文献
178.
179.
Domain characteristics such as domain shape, domain switching, and etching rate at Z-surfaces of lithium niobate (LN) single crystals are comprehensively studied from the chemical bonding viewpoint. The present work shows that the domain characteristics are closely correlated to anisotropic bonding behaviors of constituent ions, which may be regarded as a microscopic reflection of detailed conditions of the chemical bonding geometry and strength of Li+ and Nb5+ cations in the LN crystallographic frame. 相似文献
180.
We address the problem of permutation ambiguity in blind separation of multiple mixtures of multiple images (resulting, for instance, from multiple reflections through a thick grass plate or through two overlapping glass plates) with unknown mixing coefficients. In this paper, first we devise a generalized multiple correlation measure between one gray image and a set of multiple gray images and derive a decorrelation-based blind image separation algorithm. However, many blind image separation methods, including this algorithm, suffer from a permutation ambiguity problem that the success of the separation depends upon the selection of permutations corresponding to the orders of the update operations. To solve the problem, we improve the first algorithm above by decorrelating the mixtures while searching for the appropriate update permutation using a pruning technique. We show its effectiveness through experiments with artificially mixed images and real images. 相似文献