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丹江口水库蓄水后汉江中下游水文时空变化的定量评估及其生态影响

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长江流域资源与环境 2017年第9期26卷 1476-1487页

作者：柏慕琛班璇 diplas panayiotis 肖飞武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072 水资源安全保障湖北省协同创新中心湖北武汉430072 中国科学院测量与地球物理研究所环境与灾害监测评估湖北省重点实验室湖北武汉430077 Department of Civil and Environmental Engineering Lehigh University

采用变化范围法(RVA)定量研究了丹江口水库蓄水后汉江中下游水文情势的时空变化,评估出汉江干流变化度最大的江段和水文特征指标类别,分析了其对应的生态影响,并针对汉江流域的四大家鱼和水华问题进行了敏感水文指标的变化度分析。结果... 详细信息

采用变化范围法(RVA)定量研究了丹江口水库蓄水后汉江中下游水文情势的时空变化,评估出汉江干流变化度最大的江段和水文特征指标类别,分析了其对应的生态影响,并针对汉江流域的四大家鱼和水华问题进行了敏感水文指标的变化度分析。结果显示:丹江口大坝蓄水后,汉江下游河道流量是中变化度占主导,比例范围为47~63%;水位是高变化度占主导,襄阳站和皇庄站高变化度的水文指标所占比例远大于其它站点,依次为53%和75%,各站水位较蓄水前下降了1~2 m。黄家港站高/低流量脉冲出现的频率减少(变化度为-0.49和-0.62),且持续的时间变短(变化度为-0.87和-0.74)。皇庄站和襄阳站流量和水位的月均值和极值较蓄水前减少,逆转次数在高RVA范围内较蓄水前增加(变化度为1.82)。四大家鱼产卵的敏感水文指标出现频率较蓄水前减少,且为中高变化度。下游河道枯水期流量和水位减小,增加了水华发生几率。

关键词：丹江口大坝蓄水变化范围法水文特征指标时空变化生态效应

REGIME MORPHOLOGY OF EQUILIBRIUM ALLUVIAL CHANNELS

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International Journal of Sediment Research 1999年第2期14卷 187-194页

作者： panayiotis diplas1 (Dept.of Civil Engineering Virginia Polytechnic Institute and State University, Blacksburg VA,24061, USA)

The concept of turbulent diffusion of downstream momentum in the lateral direction is employed here to develop a model for obtaining the shear stress applied by the flow upon the boundary of channels. The resulting equation, together with the equation desrcibing the balances of forces applied on a sediment particle lying on the channel boundary, are solved numerically to calculate the dimensions of equilibrium alluvial channels. More specifically, threshold channels, and channels with static banks and mobile beds are considered here. Such channels are widely used for irrigation, water supply, flood control and other purposes. The center depth and top channel width obtained from the present model compare favorably with the corresponding values measured from natural streams and laboratory flumes that have reached an equilibrium state.

关键词： Equilibrium alluvial channel Regime morphology shear stress Numerical model

长江葛洲坝下游鱼类资源量的关键水文指标识别

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水利水电科技进展 2019年第1期39卷 15-20页

作者：班璇 diplas panayiotis 吕晓蓉肖飞李书娟中国科学院测量与地球物理研究所环境与灾害监测评估湖北省重点实验室湖北武汉430077 Department of Civil and Environmental Engineering Lehigh University 重庆市江北区生态环境监测站重庆430000

采用遗传规划法和相关系数法识别影响鱼类资源量的关键水文指标,结果显示坝下经济鱼类天然捕捞产量与年最大流量、高流量脉冲历时、10月和12月的月均流量正相关;四大家鱼鱼苗丰度与涨水率、7日最大流量、5月和6月的月均流量正相关;中华... 详细信息

采用遗传规划法和相关系数法识别影响鱼类资源量的关键水文指标,结果显示坝下经济鱼类天然捕捞产量与年最大流量、高流量脉冲历时、10月和12月的月均流量正相关;四大家鱼鱼苗丰度与涨水率、7日最大流量、5月和6月的月均流量正相关;中华鲟繁殖群体数量与基流指数和涨水率呈正相关,与年最小流量、日均流量逆转次数负相关。这些水文指标分别反映了流量的量值、变化率和历时等特征对鱼类的影响。建立了关键水文指标与鱼类资源量之间的非线性函数关系式,通过对比计算值与实测值发现遗传规划法的拟合效果明显优于相关系数法,表明遗传规划法更适用于识别影响鱼类资源量的关键水文指标。

关键词：遗传规划法相关系数法经济鱼类中华鲟四大家鱼三峡工程葛洲坝长江

Transcranial direct current stimulation efficacy in trigeminal neuralgia

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World Journal of Clinical Cases 2024年第5期12卷 1036-1038页

作者： Theodoros Fasilis Stylianos Gatzonis panayiotis Patrikelis Stefanos Korfias Athanasia Alexoudi 1^(st) Department of Neurosurgery National and Kapodistrian University of AthensAthens 10676Greece Department of Neurology Neurological Institute of AthensAthens 10676Greece

Trigeminal neuralgia is a severe,disabling pain and its deafferentation remains a challenge for health *** direct current stimulation is a non-invasive stimulation technique which finds new utility in managing ***-fore,the introduction of alternative,non-invasive,safe,and effective methods should be considered in treating patients with trigeminal neuralgia unresponsive to conventional treatment.

关键词： Trigeminal neuralgia Patient-controlled intravenous analgesia Neuromodulation Transcranial direct current stimulation

A Hybrid Immersed Boundary/Coarse-Graining Method for Modeling Inextensible Semi-Flexible Filaments in Thermally Fluctuating Fluids Dedicated to Professor Karl Stark Pister for his 95th birthday

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Computer Modeling in Engineering & Sciences 2021年第12期129卷 1243-1258页

作者： Magdalini Ntetsika panayiotis Papadopoulos Department of Mechanical Engineering University of CaliforniaBerkeleyCA94720-1740USA

A new and computationally efficient version of the immersed boundary method,which is combined with the coarse-graining method,is introduced for modeling inextensible filaments immersed in low-Reynolds number *** is used to represent actin biopolymers,which are constituent elements of the cytoskeleton,a complex network-like structure that plays a fundamental role in shape *** extension of the traditional immersed boundary method to include a stochastic stress tensor is also proposed in order to model the thermal fluctuations in the fluid at smaller *** way of validation,the response of a single,massless,inextensible semiflexible filament immersed in a thermally fluctuating fluid is obtained using the suggested numerical scheme and the resulting time-averaged contraction of the filament is compared to the theoretical value obtained from the worm-like chain model.

关键词： Semiflexible biopolymers immersed boundary method coarse-graining actin filaments fluid-structure interaction thermal fluctuations persistence length

Influence of evenness on the litter-species richness-decomposition relationship in Mediterranean grasslands

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Journal of Plant Ecology 2010年第2期3卷 71-78页

作者： panayiotis G.Dimitrakopoulos Biodiversity Conservation Laboratory Department of EnvironmentUniversity of the AegeanMytileneLesbos GR-81100Greece

Aims Human impacts on natural ecosystems induce changes in their functioning through alterations in species richness,composition and evenness of plant *** litter diversity–decomposition processes studies have only manipulated species richness,ignoring the role of ***,results from a field litterbag experiment are presented to test whether changes in evenness of species distribution in litter mixtures affected the strength of the litter-species richness–decomposition *** Ten herbaceous species abundant in Mediterranean grassland communities and representative of different genera and functional groups were *** richness was directly manipulated to produce litter mixtures of three and six plant species,as well as litter of each individual species *** level of species richness was replicated several times such that each repeat had a different species ***-and six-species litter mixtures were also treated to vary in evenness(three levels).Decomposition rate was assessed by percentage dry weight loss over the 90 days of the *** Findings Decomposition rate was positively related to the linear increase in litter-species richness and was affected by the composition of the litter-species *** rates differed significantly between evenness treatments and moreover,the strength of the positive relationship between litter-species richness and decomposition rate decreased notably in the low-evenness *** effects of evenness on decomposition rate,at different richness levels,were partially explained by the differences in the initial litter mixture’s carbon-to-nitrogen ratio within *** study reveals that shortterm decomposition rate is positively affected by both components of Mediterranean grassland litter-species diversity.

关键词： biodiversity dominance ecosystem functioning old field plant litter mixture

Treatment controversies in a rare case of a simultaneous branch retinal artery and vein occlusion secondary to hyperhomocysteinemia and hypertension

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International Journal of Ophthalmology(English edition) 2018年第12期11卷 2024-2026页

作者： panayiotis Christodoulou Ioannis Katsimpris General Hospital of Patras "Agios Andreas" Ophthalmology Clinic

Dear Editor,Combined vascular occlusions involving retinal arteries and veins have been reported in the past. Combined occlusion of the central retinal vein （CRVO） and artery （CRAO）is well described;. Cilioretinal... 详细信息

关键词： Treatment controversies in a rare case of a simultaneous branch retinal artery and vein occlusion secondary to hyperhomocysteinemia and hypertension Figure NVD FFA

Discussion 7 Slope and Channel Erosion Control

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International Journal of Sediment Research 1999年第2期14卷 353-354页

作者： panayiotis DLPLAS Shaohua Marko HSU

Nonlinear dynamic analysis of multi-base seismically isolated structures with uplift potentialⅡ:verification examples

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Earthquake Engineering and Engineering Vibration 2010年第1期9卷 83-91页

作者： panayiotis C.Roussis Panos C.Tsopelas Michael C.Constantinou Department of Civil and Environmental Engineering University of Cyprus Department of Civil Engineering University of Thessaly Department of Civil Structural and Environmental EngineeringUniversity at BuffaloState University of New York

The work presented in this paper serves as numerical verification of the analytical model developed in the companion paper for nonlinear dynamic analysis of multi-base seismically isolated structures. To this end, two numerical examples have been analyzed using the computational algorithm incorporated into program 3D-BASIS-ME-MB, developed on the basis of the newly-formulated analytical model. The first example concerns a seven-story model structure that was tested on the earthquake simulator at the University at Buflhlo and was also used as a verification example for program SAP2000. The second example concerns a two-tower, multi-story structure with a split-level seismic-isolation system. For purposes of verification, key results produced by 3D-BASIS-ME-MB are compared to experimental results, or results obtained from other structural/finite element programs. In both examples, the analyzed structure is excited under conditions of bearing uplift, thus yielding a case of much interest in verifying the capabilities of the developed analysis tool.

关键词： seismic isolation nonlinear dynamic analysis uplift verification multiple superstructures/bases