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A family of explicit algorithms for general pseudodynamic testing

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Earthquake Engineering and Engineering Vibration 2011年第1期10卷 51-64页

作者： Shuenn-Yih Chang Chi-Wei hsu Department of Civil Engineering Taipei University of Technology (NTUT) NTUT Box 2653

A new family of explicit pseudodynamic algorithms is proposed for general pseudodynamic testing. One particular subfamily seems very promising for use in general pseudodynamic testing since the stability problem for a structure does not need to be considered. This is because this subfamily is unconditionally stable for any instantaneous stiffness softening system, linear elastic system and instantaneous stiffness hardening system that might occur in the pseudodynamic testing of a real structure. In addition, it also offers good accuracy when compared to a general second-order accurate method for both linear elastic and nonlinear systems.

关键词： pseudodynamic test explicit method unconditional stability dominant mode structural dynamics instantaneous degree of nonlinearity

Comparison of capability of time integration methods in capturing dynamic loading

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Earthquake Engineering and Engineering Vibration 2010年第3期9卷 409-423页

作者： Shuenn-Yih Chang Chi-Wei hsu Department of Civil Engineering Taipei University of Technology

Numerical properties of the time integration method proposed by the first author of this paper in 2007 are the same as those of the constant average acceleration method （AAM） for linear elastic systems, except that the capability to capture dynamic loading was not explored. It was found that there were different quadrature equations to predict the next step displacement increment. A modified quadrature equation of this method was derived so that the equation to determine the next step displacement was numerically equivalent to the equation used in the constant AAM. It was verified that the original form of this method, in general, had a better capability to capture dynamic loadings than the constant AAM. This excellent property, in addition to computational efficiency, will help to make this method competitive with general secondorder accurate integration methods.

关键词： equations of motion quadrature equation constant average acceleration method integration methods

Haze formation in China: Importance of secondary aerosol

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Journal of Environmental Sciences 2015年第7期27卷 261-262页

作者： alex K.Y.Lee Department of Chemistry University of Toronto

Air pollution is the world＇s largest single environmental hazard that causes more than a few million premature deaths in 2012（World Health Organization,2014）,particularly in developing countries with rapid industrialization and *** economic growth of China in the last three decades has resulted in serious air pollution problems on both local and regional scales.

关键词： Haze formation in China Importance of secondary aerosol PM

OBLIQUE WATER WAVES IMPACTING ON A THIN POROUS WALL WITH A PARTIAL-SLIPPING BOUNDARY CONDITION

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Journal of Hydrodynamics 2011年第3期23卷 361-371页

作者： hsu Hao-Jen HUANG Liang-Hsiung Department of Civil Engineering and Hydrotech Research Institute National Taiwan University

When an incoming water wave is parallel to a porous breakwater, a paradoxical phenomenon exists in that by strictly following the potential flow boundary condition of normal flux continuity on the interfaces, the water wave permeates the wall completely, regardless of breakwater porosity. To account for this paradoxical phenomenon when solving the problem of water waves obliquely impacting on a thin porous wall, a new partial-slipping boundary condition on the thin porous wall for potential flow is proposed. Analytical results show that when the water wave is parallel to a thin porous wall （i.e., the incident angle equals to 90~）, the transmitted wave side remains quiescent, i.e., the transmitted wave side does not capture any wave energy when no viscous effect exists. This reveals that the above-mentioned paradoxical investigated in this study, which provides proper boundary information. phenomenon disappears. The viscous boundary layer effect is also conditions on a thin porous wall for viscous flows and detailed flow

关键词： oblique linear water wave thin porous wall partial-slipping boundary condition boundary layer

Levels of rhizome endophytic fungi fluctuate in Paris polyphylla *** as plants age

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Plant Diversity 2017年第1期39卷 60-64页

作者： Tao Liu alex Greenslade ShengchaoYang Yunnan Research Center on Good Agricultural Practice for Dominant Chinese Medicinal Materials Yunnan Agricultural University Kunming 650201China Biological Chemistry and Crop Protection Rothamsted Research Harpenden UK

Paris polyphylla var. yunnanensis is an important medicinal plant with abundant saponins that are widely used in the pharmaceuticals industry. It is unclear why the levels of active ingredients increase as these plants age. We speculated that the concentrations of those components in the rhizomes are mediated by fungal endophytes. To test this hypothesis, we took both culture-dependent and-independent(metagenomics) approaches to analyze the communities of endophytic fungi that inhabit those rhizomes in plants of different age classes(four, six, and eight years old). In all, 147 isolates representing 18 fungal taxa were obtained from 270 segments(90 per age class). Based on morphological and genetic characteristics, Fusarium oxysporum(46.55% frequency of occurrence) was the predominant endophyte,followed by Leptodontidium sp.(8.66%) and Trichoderma viride(6.81%). Colonization of endophytic fungi was maximized in the eight-year-old rhizomes(33.33%) when compared with four-year-old(21.21%) and six-year-old(15.15%) rhizomes. Certain fungal species were present only at particular ages. For example,Alternaria sp., Cylindrocarpon sp., Chaetomium sp., Paraphaeosphaeria sporulosa, Pyrenochaeta sp., Penicillium swiecickii, T. viride, and Truncatella angustata were found only in the oldest plants. Analysis of(metagenomics) community DNA extracted from different-aged samples revealed that, at the class level,the majority of fungi had the highest sequence similarity to members of Sordariomycetes, followed by Eurotiomycetes and Saccharomycetes. These results were mostly in accord with those we obtained using culture methods. Fungal diversity and richness also changed over time. Our investigation is the first to show that the diversity of fungi in rhizomes of P. polyphylla var. yunnanensis is altered as plants age, and our findings provide a foundation for future examinations of useful compounds.

关键词： Medicinal plants Endophytic fungi Paris polyphylla var.yunnanensis

On helical behavior of turbulence in the ship wake

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Journal of Hydrodynamics 2013年第1期25卷 83-90页

作者： GOLBRAIKH Ephim EIDELMAN alexander SOLOVIEV alex Physics Department Ben-Gurion University of the Negev Mechanical Engineering Department Ben-Gurion University of the Negev Oceanographic Center NOVA South eastern University

Turbulent ship wake conservation at a long distance is among unsolved problems at present. It is well known that far wakes have a vortical structure and slowly expand with distance. As was obtained by Dubrovin et al., slow expansion of the wake may be related to the distribution of turbulent viscosity in it. In our work we study the effect of helicity in the wake on the behavior of turbulent viscosity. Taking into account the helical nature of the wake, we can clarify the difference between turbulence inside and outside the wake on the one hand and slowing down of its expansion with time on the other hand.

关键词： ship wake turbulent ship wake helical turbulence

Increased salt sensitivity induced by sensory denervation: role of superoxide

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Acta Pharmacologica Sinica 2004年第12期25卷 60-66页

作者： alex F CHEN,Donna H WANG Department of Medicine and Pharmacology & Toxicology Michigan State University East Lansing MI 48824 USA Department of Medicine and Pharmacology & Toxicology Michigan State University East Lansing MI 48824 USA

AIM: To test the hypothesis that production of superoxide in mesenteric resistance arteries is increased and con- tributes to the development of hypertension induced by sensory denervation plus high salt intake. METHODS: Newborn Wistar rats were given capsaicin 50 mg/kg sc on the 1st and 2nd d of life. After weaning, male rats were grouped as follows and treated for 3 weeks with: capsaicin pretreatment plus normal sodium diet (0.5 %, CAP-NS), CAP plus high sodium diet (4 %, CAP-HS), control plus NS (CON-NS), or CON-HS. Both tail-cuff systolic blood pressure and mean arterial pressure (MAP) were measured in each of the groups. Western blot analysis was used for measurement of manganese superoxide dismutase (MnSOD) and endothelial nitric oxide synthase (eNOS) in the mesenteric resistance arteries. Lucigenin chemiluminescence assay was used for superoxide production in the mesenteric resistance arteries. The Griess method was used for measurement of nitrite/nitrate levels in plasma. RESULTS: Both tail-cuff pressure and MAP were higher in CAP-HS compared with CAP-NS, CON-HS, and CON- NS rats (P<0.05). Both MnSOD and eNOS in the mesenteric resistance arteries were increased in CAP-HS compared with CAP-NS, CON-HS, and CON-NS (P<0.05). However, nitrite/nitrate levels in plasma were not different among 4 groups. Acute iv administration of tempol, a membrane-permeable superoxide scavenger, de- creased MAP in both CAP-HS and CON-HS when compared with their respective controls. However, the de- creases of MAP between these two groups were not different. Chronic treatment with tempol failed to prevent the development of hypertension in CAP-HS rats. Superoxideproduction in the mesenteric resistance arteries was increased in CAP-HS compared with CAP-NS, CON-HS, and CON-NS (P<0.05). However, chronic treatment with tempol did not prevent the increase of mesenteric superoxideproduction in CAP-HS rats. CONCLUSIONS: Regardless of increased vascular MnSOD levels, salt

关键词： superoxides tempol afferent neurons capsaicin denervation dietary sodium chloride nitric oxide

Isothermal section of ternary Sn-Zn-Ni phase equilibria at 250℃

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Progress in Natural Science:Materials International 2011年第5期21卷 386-391页

作者： Sinn-wen CHEN Chia-ming hsu Chin-yi CHOU Che-wei hsu Department of Chemical Engineering National Tsing Hua University

Ternary Sn-Zn-Ni alloys were prepared and equilibrated at 250℃for 4-15 *** phases formed in these equilibrated alloys were determined *** isothermal section of Sn-Zn-Ni system was constructed,based on the phase diagrams of the three constituent binary systems and the ternary phase equilibria data,determined in this study and referenced in literatures.12 single-phase regions were identified in the Sn-Zn-Ni ternary system at 250℃,including the three ternary compounds,δ,τ1andτ*** were 13 ternary phase regions and 23 binary phase regions in the 250℃Sn-Zn-Ni isothermal *** solubility of Zn in the binary Sn-Ni compounds is significant,and is 15.1%（mole fraction） in the Ni3Sn phase.

关键词： Pb-free solder phase equilibria Sn-Zn Ni

Detection and interpretation of the Earth's free oscillations excited by the great Sumatra-Andaman earthquake with GGP station data

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Earthquake Science 2011年第2期24卷 151-162页

作者： Houtse hsu Institute of Geodesy and Geophysics Chinese Academy of Sciences

The mode serials of the Earth’s free oscillation provide some important information on the Earth’s deep structure and superconducting gravimeters （SG） can investigate the phenomena of the Earth’s free oscillations with high accuracy. The great Sumatra-Andaman earthquake fully excited the Earth’s free oscillations and these signals were perfectly recorded by five superconducting gravimeters in the globe. After the pre-treatment and spectral analysis on the SG observation data, we obtained the experimented mode serials of the Earth’s free oscillations consisting of 147 modes with GGP station data. These observed modes were themselves some new important data for the study of the Earth’s deep structure. On the basis of the discussions on some checked inner-core-sensitive modes, we distinguished three layers from the inner core, and the boundary of the upper layer was compatible with the formerly known transition zone in the inner core based on seismic body waves and supported that there were the hemispherical variation and very lower shear velocity zone in the lower inner core.

关键词： Sumatra-Andaman earthquake GGP station data Earth’s free oscillation Earth’s inner core core sensitive mode