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FIsH AssEMBLAGE REsPONsEs TO DIFFERENT sECONDARY CHANNEL DEsIGNs IN THE LOWER MIssIssIPPI RIVER,u.s.a.:A TEMPLATE FOR RIVER REsTORATION

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水生生物学报 2018年第6期42卷 1089-1106页

作者： KAIsER Joseph E. sMITH shannon C.F. sCHRAMM Jr.,HAROLD L. EGGLETON Michael A. Department of Aquaculture and Fisheries University of Arkansas at Pine Bluff1200 N.UniversityMail Slot 4912Pine BluffArkansas 71601U.S.A u.s.Geological survey Mississippi Cooperative Fish and Wildlife Research UnitMississippi State University

The lower Mississippi River(LMR) has been heavily modified for multiple human purposes such as navigation, flood control, and bank stabilization. However, the LMR simultaneously supports a diverse fish fauna that includes recreational and commercial fisheries. Due to river training and diversion structures constructed during the past 80 years, the historic characteristics of the LMR have been drastically altered and have likely influenced fishes and fisheries in the system. One common restoration measure used throughout the LMR has been to "notch" wing-dike structures that close secondary(side) river channels. Dike notching allows year-round flows through secondary channels, which enhances habitat diversity and promotes biological productivity at the ecosystem scale. Although notching is presumed good for LMR fishes and other biota, few studies have examined its effects on fish assemblages. In this study, fish assemblages were sampled at seven LMR secondary channels spanning from river kilometer(rkm) 628(Lou.s.ana-Mississippi, u.s.a.) upstream to rkm 1504(Missouri-Kentucky, u.s.a.). Four secondary channels were termed "permanent"(i.e.,with notched dikes) while three secondary channels were termed "temporary"(i.e., without notched dikes).Fishes were sampled by boat-mounted electrofishing conducted during falling and low stages from1995—1997. Fish assemblages differed between permanent and temporary secondary channels, and varied somewhat between falling and low stages. Gizzard shad(Dorosoma cepedianum), threadfin shad(D. petenense), and white bass(Morone chrysops) demonstrated consistent preferences for low-current conditions associated with temporary secondary channels. Conversely, blue catfish(Ictalurus furcatus), flathead catfish(Pylodictis olivaris), and freshwater drum(Aplodinotus grunniens) were more associated with permanent secondary channels. Future restoration strategies in the LMR should consider dike notching and resultant maintenance of permanent seconda

关键词： Mississippi River secondary channels Dikes Fish assemblages River restoration River rehabilitation

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Nucleation barrier of fcc(γ)→hcp(ε) martensitic transformation in Fe-based alloys

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science China(Technological sciences) 2004年第1期47卷 121-128页

作者： HuANG Xing CHEN shipu school of Materials science and Engineering Shanghai Jiao Tong University Shanghai 200030 China School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai 200030 China

Based on the dislocation theory and Olson's stacking fault model, a model describing the nucleation of an hcp(ε) martensite embryo at low-angle grain boundary is proposed with the influence of external stress field taken into account. The dependences of temperature (T), shear stress (τ) and dislocation density at grain boundary on the martensite nucleation in FeMnsi based alloy, as an example, are numerically simulated. It has been shown that there exist the subcritical and critical embryos during the course of ε-phase nucleation. The free energy difference between them is just the energy barrier of embryo growth. Depending on T and τ. the characteristic embryo sizes may vary in wide ranges and decreases with increasing σ and decreasing T. The energy condition of martensitic transformation at M s and critical shear stress (τc) is discussed from the viewpoint of kinetics and thus the TEM observed result that stacking fault energy is not zero at M s temperature is reasonably explained. Besides, it is predicted that the high dislocation density at grain boundary can promote the nucleation of fcc→hcp transformation in Fe-based alloys.

关键词： martensitic transformation, stacking fault mechanism, nucleation, energy barrier, temperature, stress, dislocation density.

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Dependences of longleaf pine(Pinus palustris) natural reproduction on environments above ground

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Journal of Forestry Research 2014年第3期25卷 565-570页

作者： Qiuju Guo Dexiang Wang Xunru Ai Lan Yao College of Forestry and Horticulture Hubei University for Nationalities College of Forestry Northwest A&F University

We studied relations between natural seedling reproduction and above ground environment in a longleaf pine ecosystem. Forty-eight 0.05 ha circular plots were sampled under single-tree selection, group-tree selection and control stands in three main longleaf pine areas in south Alabama, usA. We measured six above-ground environment factors, viz. canopy closure, stand density, basal area, average tree height, understory cover and PAR under canopy. We employed forward, back-ward and stepwise selection regression to produce one model. Three main variables：canopy closure, stand density and basal area, were left in the model; light, PAR and understory cover were not incorporated into the model at the 0.10 significance level. Basal area was a positive pa-rameter, while canopy closure and stand density were negative parame-ters. Canopy closure was the main parameter in the model. The model proved to be meaningful, and has potential to provide useful guidance for future work.

关键词： seedling reproduction number selection regression analysis model

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Optical gravitational wave detectors on the ground and in space:theory and technology

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Research in Astronomy and Astrophysics 2010年第10期10卷 956-1004页

作者： Jean-Yves Vinet ARTEMIs Observatoire de la Cte d'Azur université de Nice-sophia Antipolis 06304 NICE France

Major predictions of General Relativity, unforeseen at the beginning of the preceding century, are now under investigation. The existence of black holes of any mass from tens to billions of solar masses is now established, and the physics around these objects begins to be studied through direct observations in a wide electromagnetic spectrum from visible light to X-rays. General relativity, however, provides an extra medium which carries more information on the regions of intense gravitational field, namely gravitational waves （GWs）. Due to their extremely weak coupling to matter, GWs are precisely generated in those regions of spacetime undergoing strong curvature, which is very exciting for modern astrophysics. On the other hand, this weak coupling makes it difficult for GWs to cause appreciable effects in human made instruments. This is why technology of GW detectors took such a long time to reach a sensitivity level consistent with GW amplitudes predicted by theoretical models of sources. In the present status, apart from resonant solid detectors, two large interferometric antennas （LIGO in the usA and the French-Italian Virgo） are beginning to produce data, and a joint EsA-NAsA space mission, resulting from a wide effort of European and American groups, is reaching a crucial approval phase. The aim of the present review is to give the theoretical bases of GW detectors using light.

关键词： gravitation -- gravitational waves -- interferometry

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Tectonic Implications of Paleomagnetic Results From upper silurian series Along the Hexi Corridor, Gansu, China

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science China Chemistry 1993年第6期36卷 720-728页

作者：孟自芳 Robert s. Coe Lanzhou Institute of Geology Academia Sinica Lanzhou 730000 PRC university of California at santa Cruz USA

Characteristic directions of remanent magnetization of 38 samples from upper silurian series (Hanxia Formation) along the Hexi Corridor passed fold test at a 99% confidence level. The corresponding paleopole is located at 45.1°N, 5.5°E (A_(95)= 4.7°, κ=25.1), close to the Late Permian pole for this area (41.4°N, 358.6°E; A_(95)= 4.3°, κ=26.6). However, there appears an obvious difference between paleolatitudes for these two stages (6°±). Based on paleomagnetic data, it can be deduced that the Hexi Corridor had probably been the western extension of the North China Block by the time of Late silurian and kept being tectonically mobile compared with the principal parts of the North China Block. In addition, paleomagnetic data reveal that the Hexi Corridor experienced a southward displacement of about 600 km during the Late Paleozoic Era.

关键词： Hexi Corridor upper silurian series southward displacement.

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Ordering and Reordering of Nanophase FeAl intermetallics synthesized by Mechanical Alloying

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Chinese Physics Letters 1996年第11期13卷 851-854页

作者： TAN Qi Department of Materials science and Engineering University of Illinois at Urbana-Champaign 105 South Goodwin AvenueUrbanaIL61801U.S.A.

Nanophase B_(2)-FeAl intermetallics was directly synthesized by room temperature ball milling and heat *** atomic ordering can be realized when compositional shift during milling is compensated and can be accelerated by heat *** ordered nanophase FeAl can be obtained by atomic reordering during annealing at temperatures below 500℃,which results in no significant grain growth.

关键词： intermetallics grain Alloying

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Measurement of friction coefficient in aluminum sheet warm forming

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Journal of Harbin Institute of Technology(New series) 2005年第3期12卷 328-330页

作者：郭正华李志刚黄重九董湘怀 state Key Lab of Plastic Forming simulation and Die &Mold Technology Huazhong university of science and Technology Wuhan 430074 China

Aluminum alloy sheets are used more and more to manufacture auto panels. Because the friction behavior is very complicated, it is necessary to study the friction during the aluminum sheet warm forming process. The author has designed a new probe sensor based on an online tribotest method which directly measures friction coefficient in the forming process. Experiments of cup drawing have been conducted and the friction coefficients under different forming conditions have been measured. The results indicate that the forming parameters, such as forming temperature, blankholding force and lubrication status have great effect upon the friction coefficient.

关键词： probe sensor tribotest method aluminum sheet warm forming friction coefficient

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Minimum energy optimal external torque control of human binocular vision

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Control Theory and Technology 2020年第4期18卷 431-458页

作者： Bijoy K.Ghosh Bhagya Athukorallage Department of Mathematics and statistics Texas Tech UniversityLubbockTX 79409-1042USA school of Automation Engineering University of Electronic Science and Technology of ChinaChengduSichuan 610054China

In this paper,we consider eyes from the human binocular system,that simultaneously gaze on stationary point targets in space,while optimalal skipping from one target to the next,by rotaing their individual gaze *** head is assume fixed on the torso and the rotaing gaze direction of the two eyes are assumed restricted to pass through a point in the visual *** is further assumed that,individullly the rotations of the two eyes satisfy the well known Listing's *** formulate and study acombined optimal gaze rotation for the two eyes,by constructing a single Riemanmian metric,on the asociaced parameter *** goal is to optimally rotate so that the convergent gaze changes between two pre-specified target points in a finite time interval[0,1].The cost function we choose is the total energy,measured by the L2?norm,of the six extenal torques on the binocular *** torque functions are synthesized by solving an associated*two-point boundary value *** paper demonstrates,via simulation,the shape of the optimal gaze trajectory of the focused point of the bin-ocular *** Euclidean distance between the initial and the final point is compared to the arc:length of the optimal *** consumed *** computed for diferent eye movement chores and discussed in the *** simulation we observe that certain eye movement maneuvers are energy fficicnt and demonstrate that the optimal external torque is a linear function in *** also explore and conclude that spitting an arbitry opimal eye movement into optimal vergence and version components is not energy fficient although this is how the human oculomotor control seems to *** gaze tajectories and opimal extermal torque functions reported in this paper is new.

关键词： Binocular vision Riemamian gcometry Optimal control Human eye movement

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synthesis of N1-substituted-3-aryl-4-alkyl-4, 5-dihydro-1H-1-pyra-zolethiocarboxamide as Novel small Molecule Inhibitors of Cysteine Protease of ***

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Chinese Chemical Letters 2002年第11期13卷 1043-1046页

作者： ChunGuO XiaoHuiDu 等 schoolofPharmaceuticalEngineering ShenyangPharmaceuticalUniversityShenyang110016 schoolofPharmacy UniversityofCaliforniaSanFranciscoCA94143U.S.A

A series of N1-substituted-3-aryl-4-alkyl-4, 5-dihydro-1H-1-pyrazolethiocarboxamide were prepared from the Mannich bases of aryl ketones in good yields. some derivatives were found to be active against the cysteine p... 详细信息

关键词： N1-substituted-3-aryl-4-alkyl-4 5-dihydro-1H-1-pyrazolethiocarboxamide synthesis T.cruzi. cysteine protease inhibitor.

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Comparison of deep convolutional neural network classifiers and the effect of scale encoding for automated pavement assessment

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第2期10卷 258-275页

作者： Elham Eslami Hae-Bum Yun Department of Civil Environmental and Construction EngineeringUniversity of Central FloridaOrlandoFL 32816USA

Deep learning has received a growing interest in recent years for detecting different types of pavement distresses and automating pavement condition assessment.A proper choice of deep learning models is key for successful pavement assessment *** this study,we first present a comprehensive experimental comparison of state-of-the-art image classification models to evaluate their performances on 11 pavement objects *** experiments are conducted in different dimensions of comparison,including deep classifier architecture,effects of network depth,and computational *** convolutional neural network(CNN)classifiers widely used in transportation applications,including VGG16,VGG19,ResNet50,DenseNet121,and a generic CNN(as the control model),are tested with a comprehensive pixel-level annotated dataset for 11 different distress and non-distress classes(uCF-PAVE 2017).In addition,we investigate a simple yet effective approach of encoding contextual information with multi-scale input tiles to classify highly random pavement objects in size,shape,intensity,texture,and *** comparison results show that the multi-scale approach significantly improves the classification accuracy for all compared deep classifiers at a negligible extra computational ***,we provide recommendations of how to improve the classification performance of deep CNNs for automated pavement condition assessment based on the comparison results.

关键词： Road damage detection Automated pavement condition assessment Convolutional neural networks Deep learning Multi-class classification

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