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Journal of Thermal Science 2004年第4期13卷 315-320页

作者： A. THAKKER M.El. HEMRY Wave Energy research team Department of Mechanical and Aeronautical Engineering University of Limerick IrelandWave Energy Research Team Department of Mechanical and Aeronautical Engineering University of Limerick Ireland

The objective of this paper is to present the performance comparison of 2D Computational Fluid Dynamics (CFD) analysis with experimental analysis of 0.6 m impulse turbine with fixed guide vanes for both 0.6 and 0.7 hub to tip ratio (H/T). Also the comparison of 2D CFD analysis of the said turbine with different values of H/T ranging from 0.5 to 0.7. A 2D-cascade model was used for CFD analysis while uni-directional steady flow was used for experimental analysis. The blade and guide vane geometries are based on 0.6 m rotor diameter, with optimum profile, and different H/T of 0.5, 0.6 and 0.7. It was concluded from 2D CFD analysis that 0.5 H/T ratio performances was higher than that of 0.6 and 0.7 H/T at peak efficiency and the operational flow range for 0.5 H/T was found to be wider than that of 0.6 and 0.7 H/T ratio.

关键词： wave energy impulse turbine computational fluid dynamics (CFD).

How topography and neighbor shape the fate of trees in subtropical forest restoration:Environmental filtering and resource competition drive natural regeneration

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Forest Ecosystems 2024年第1期11卷 73-86页

作者： Haonan Zhang Xingshuo Zhang Yingying Lv Yanyan Ni Baokun Xu Xiangnan Han Xiao Cao Qingpei Yang Wanggu Xu Zhedong Qian Innovative research team for Forest Restoration Mechanisms Nanjing Institute of Environmental SciencesMinistry of Ecology and Environment(MEE)Nanjing 210042China College of Forestry Jiangxi Agricultural UniversityNanchang 330045China

The structure of plant communities at local scales depends on both the spatial heterogeneity of abiotic environmental factors and the biotic interactions within the ***,although environmental filtering due to microtopographic heterogeneity and resource competition among plants caused by spatial variation in tree density and size are considered to be very important in explaining the mechanisms of community assembly,their effects on the processes of individual mortality and recruitment in natural forest regeneration,as well as their relative contributions,are still poorly *** address this,we established a 12-ha permanent plot in a subtropical evergreen broad-leaved forest area and measured microtopographic variables such as elevation,slope,aspect,and terrain position index(TPI)using a total *** monitored the individual mortality and recruitment in forest natural regeneration through repeated surveys at 5-year *** fitted spatial covariance models to jointly use multiple factors from three groups of variables(microtopographic effect,neighborhood density effects,neighborhood size effects)as explanatory variables to analyze their roles in driving the mortality and recruitment of all individual and 12 dominant species in forest natural regeneration at the neighborhood *** results show that:(1)In the crucial early stages of secondary forest restoration,natural regeneration is influenced by a synergy of environmental filtering,due to microtopographic heterogeneity,and resource competition among plants.(2)For distinct species responses,evergreen dominant species'mortality is largely explained by neighborhood effects,while deciduous species are more affected by topographic ***,the adverse effects of larger conspecific trees on younger trees indicate a pattern of competitive pressure leading to mortality among regenerating trees,such pattern emphasis the influence of parent trees on natural regeneration.(3)As trees g

关键词： Natural regeneration Microtopography Neighborhood effects Mortality and recruitment

Dispersal of invasive species by drifting

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Current Zoology 2011年第6期57卷 818-827页

作者： M.C. VAN RIEL G. VAN DER VELDE A. BIJ DE VAATE Radboud University Nijmegen Institute for Water and Wetland Research Department of Animal Ecology and Ecophysiology Section Aquatic Animal Ecology Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands team Freshwater ecology DLO-Alterra P.O. Box 47 6700 AA Wageningen The Netherlands Netherlands Centre for Biodiversity Naturalis EO. Box 9517 2300 RA Leiden The Netherlands Waterfauna Hydrobiologisch Adviesbureau Oostrandpark 30 8212 AP Lelystad The Netherlands

Drifting can be an effective way for aquatic organisms to disperse and colonise new areas. Increasing connectivity between European large rivers facilitates invasion by drifting aquatic macroinvertebrates. The present study shows that high abundances of invasive species drift in the headstream of the river Rhine. Dikerogammarus villosus and Chelicorophium cur- vispinum represented up to 90% of the total of drifting macroinvertebrates. Drift activity shows seasonal and diel patterns. Most species started drifting in spring and were most abundant in the water column during the summer period. Drift activity was very low during the winter period. Diel patterns were apparent; most species, including D. villosus, drifted during the night. Drifting macroinvertebrates colonised stony substrate directly from the water column. D. villosus generally colonised the substrate at night, while higher numbers of C. curvispinum colonised the substrate during the day. It is very likely that drifting functions as a disper- sal mechanism for crustacean invaders. Once waterways are connected, these species are no longer necessarily dependent on dispersal vectors other than drift for extending their distribution range

关键词： Amphipods Invaders Colonization Drift Daily rhythms Seasonal variation

An Efficient and Spam-Robust Proximity Measure Between Communication Entities

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Journal of Computer Science & Technology 2013年第2期28卷 394-400页

作者： Joo Hyuk Jeon Jihwan Song Jeong Eun Kwon Yoon Joon Lee Man Ho Park Myoung Ho Kim Department of Computer Science Korea Advanced Institute of Science and Technology Biz Solution team SK Telecom Information Technology R&D Center Mobile Communication Convergence research team Electronics and Telecommunications Research Institute

Electronic communication service providers are obliged to retain communication data for a certain amount of time by their local laws. The retained communication data or the communication logs are used in various applications such as crime detection, viral marketing, analytical study, and so on. Many of these applications rely on effective techniques for analyzing communication logs. In this paper, we focus on measuring the proximity between two communication entities, which is a fundamental and important step toward further analysis of communication logs, and propose a new proximity measure called ESP （Efficient and Spam-Robust Proximity measure）. Our proposed measure considers only the （graph- theoretically） shortest paths between two entities and gives small values to those between spam-like entities and others. Thus, it is not only computationally efficient but also spam-robust. By conducting several experiments on real and synthetic datasets, we show that our proposed proximity measure is more accurate, computationally efficient and spam-robust than the existing measures in most cases.

关键词： proximity closeness spam electronic communication

Phase-field model of precipitation processes with coherency loss

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npj Computational Materials 2021年第1期7卷 338-348页

作者： Tian-Le Cheng You-Hai Wen National Energy Technology Laboratory AlbanyORUSA Leidos research Support team AlbanyORUSA

A phase-field model is proposed to simulate coherency loss coupled with microstructure evolution.A special field variable is employed to describe the degree of coherency loss of each particle and its evolution is governed by a Ginzburg-Landau type kinetic *** the sake of computational efficiency,a flood-fill algorithm is introduced that can drastically reduce the required number of field variables,which allows the model to efficiently simulate a large number of particles sufficient for characterizing their statistical features during Ostwald *** model can incorporate size dependence of coherency loss,metastability of coherent particles,and effectively incorporate the underlying mechanisms of coherency loss by introducing a so-called differential energy *** model is applied to simulate coarsening of Al3Sc precipitates in aluminum alloy and comprehensively compared with *** results clearly show how the particle size distribution is changed during coherency loss and affects the coarsening rate.

关键词： coherency alloy microstructure

Identification of a dual functional betulinic acid analog for the treatment of osteoarthritis by phenotypic screening

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Science China Life Sciences 2025年第1期68卷 300-302页

作者： Ze-Min Lin Mai Xiang Wen-Hui Wei Shu-Hui Fan Li Chen Jie Wang Xiao-Qian Yang Chun-Hao Yang Shi-Jun He Jian-Ping Zuo Laboratory of Immunopharmacology State Key Laboratory of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of Sciences School of Pharmacy University of Chinese Academy of Sciences School of Pharmacy Nanjing University of Chinese Medicine State Key Laboratory of Drug research Department of Medicinal ChemistryShanghai Institute of Materia MedicaChinese Academy of Sciences Innovation research Institute of Traditional Chinese Medicine Shanghai University of Traditional Chinese Medicine Experiment Center for Science and Technology Shanghai University of Traditional Chinese Medicine

Dear Editor, Phenotypic drug discovery, which observes compound effects on physiology,has given way to targeting specific molecules, but has revived by using modern methods to find drugs based on therapeutic outcomes in disease models(Vincent et al., 2022). Osteoarthritis(OA) is a prevalent chronic joint disorder, primarily affecting knee joints, with osteoclast activation due to low-grade inflammation resulting in increased bone resorption and structural changes in the joint(Katz et al.,2021).

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Earthquake simulation test of circular reinforced concrete bridge column under multidirectional seismic excitation

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Earthquake Engineering and Engineering Vibration 2006年第1期5卷 103-110页

作者： Junichi Sakai Shigeki Unjoh Earthquake Engineering research team Earthquake Disaster Prevention Research Group Public Works Research InstituteTsukuba Ibaraki 305-8516 Japan

Structures behave multi-directionally when subjected to earthquake excitation. Thus, it is essential to evaluate the effect of multidirectional loading on the dynamic response and seismic performance of reinforced concrete bridge columns in order to develop more advanced and reliable design procedures. To investigate such effects, a 1/4 scaled circular reinforced concrete bridge column specimen was tested under two horizontal and one vertical components of a strong motion that has long duration with several strong pulses. Damage progress of reinforced concrete columns subjected to strong excitation was evaluated from the test. The test results demonstrate that the lateral force response in the principal directions become smaller than computed flexural capacity due to the bilateral flexural loading effects, and that the lateral response is not significantly affected by the fluctuation of the axial force because the horizontal response and axial force barely reached the maximum simultaneously due to difference of the predominant natural periods between the vertical and the horizontal directions. Accuracy of fiber analyses is discussed using the test results.

关键词： multidirectional seismic excitation reinforced concrete bridge columns shake table test nonlinear dynamic analyses fiber analysis

Analyzing Sequential Patterns in Retail Databases

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Journal of Computer Science & Technology 2007年第2期22卷 287-296页

作者： Unil Yun Electronics and Telecommunications research Institute Telematics & USN Research Division LBS/Telematics Convergence Research Team 161 Gajeong-dong Yuseong-gu Daejeon 305-700 Korea

Finding correlated sequential patterns in large sequence databases is one of the essential tasks in data mining since a huge number of sequential patterns are usually mined, but it is hard to find sequential patterns with the correlation. According to the requirement of real applications, the needed data analysis should be different. In previous mining approaches, after mining the sequential patterns, sequential patterns with the weak affinity are found even with a high minimum support. In this paper, a new framework is suggested for mining weighted support affinity patterns in which an objective measure, sequential ws-confidence is developed to detect correlated sequential patterns with weighted support affinity patterns. To efficiently prune the weak affinity patterns, it is proved that ws-confidence measure satisfies the anti-monotone and cross weighted support properties which can be applied to eliminate sequential patterns with dissimilar weighted support levels. Based on the framework, a weighted support affinity pattern mining algorithm （WSMiner） is suggested. The performance study shows that WSMiner is efficient and scalable for mining weighted support affinity patterns.

关键词： data mining sequential pattern mining sequential ws-confidence weighted support affinity

Demographic mechanisms of disturbance and plant diversity promoting the establishment of invasive Lupinus polyphyllus

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Journal of Plant ecology 2017年第3期10卷 510-517页

作者： Miia Jauni Satu Ramula Department of Biology Section of EcologyUniversity of Turku20014 TurkuFinland Aronia Coastal Zone research team Åbo Akademi University and Novia University of Applied SciencesRaseborgsvägen 910600 EkenäsFinland

Aims Community characteristics,such as disturbances and interspecific competition that affect the availability of microsites and resources,contribute to the success or failure of the establishment of exotic plant *** particular,these two community characteristics may have adverse effects on plant emergence and survival,which are particularly important for population establishment and there-fore it may be necessary to consider both these vital rates simul-taneously when assessing demographic ***,we investigated the impacts of disturbance and interspecific compe-tition on the establishment of a perennial invasive herb,Lupinus polyphyllus *** Over the course of 2 years,we conducted an experiment in 10 populations of this species in Finland in which we manipulated the levels of soil *** recorded community charac-teristics(*** number of vascular plant species,vegetation height,and the proportions of bare ground,litter and moss),and observed the emergence and survival of *** individuals in study *** Findings A mild disturbance(breaking the soil surface mechanically)slightly increased seedling emergence but did not affect plant ***,an intense disturbance(vegetation and litter removal)had no effect on seedling emergence,although it significantly increased the proportion of bare ground and,consequently,seedling *** was not affected by the height of the surrounding vegetation,but both seedling emergence and plant survival increased with an increasing number of plant species in the study *** find-ings demonstrate that single disturbance events may considerably promote the establishment of invasive herbs,although the overall effect and demographic mechanisms behind the increased establish-ment are likely to vary depending on disturbance ***,our results suggest that species diversity per se may not be a crucial mechanism for locally preventing the establishment of exoti

关键词： community invasibility interspecific competition invasive species species richness vital rates

Investigating the pharmacological basis and mechanisms of the anti-thrombotic effects of Paeoniae Radix Rubra， both pre- and post-stir-frying with rice wine

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Food Science and Human Wellness 2025年

作者： Jiaxu Zhang Jian Guan Ajiao Hou Wenying Niu Haixue Kuang Liu Yang Hai Jiang Key Laboratory of Basic and Application research of Beiyao， Heilongjiang University of Chinese Medicine， Ministry of Education

Paeoniae Radix Rubra (PRR) is a commonly used traditional Chinese medicine known for promoting blood circulation and alleviating pain. Stir-frying PRR with rice wine enhances its effectiveness in improving blood flow and resolving stasis. To explore the pharmacodynamic basis and mechanisms behind PRR's anti-thrombotic effects—both pre- and post-stir-frying—a comprehensive approach combining pharmacological research， metabolomics， and chemistry was employed. Fraction inter-cross validation experiments， pharmacological assessments， and metabolomic analyses confirm the efficacy of the fraction separation process. Wine-stir-fried PRR (WPRR) shows superior blood activation compared to PRR. PRR mainly affects the TCA cycle and sphingolipid metabolism pathways through its small molecules， enhancing coagulation and fibrinolysis systems' functionality. All the subdivided components of WPRR have anti-thrombotic effects， especially polysaccharides and oligosaccharides. WPRR improves thrombotic conditions in rat blood stasis by modulating arachidonic acid metabolism， TCA cycle， lipid status enhancement， and angiogenesis stimulation while regulating platelet adhesion and aggregation. In conclusion， compared with PRR， the main material basis for the blood-activating efficacy of WPRR has transformed from small molecule compounds to polysaccharide and oligosaccharide components. The action pathways of WPRR in exerting anti-thrombotic efficacy have increased. The polysaccharide components in WPRR might possess considerable potential for being developed into natural anti-thrombotic drugs.

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