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| 1 | EROSION RATES ON UPLAND AREAS IN THE MIDSOUTH USA显示文摘This study documents the erosivity of rainfall, the high erodibility of soils, and reduction in annualand storm soil loss rates by conservation tillage at Holly Springs, Mississippi. Holly Springs is innorthern Mississippi in the Midsouth United States. Rainfall characteristic data and runoff dare wereexarmined for single storms and for cultivated fallow conditions for Loring (Typic Fragiudalfs) andLexington (Typic Paleudlfs) soils during 1963 through 1968 using data from 135 single storm events.Rainfall erosion index (EI) was the best single estimator among those rainfall characteristics studied to estimatC siol loss during the storms. Soil losses from a cultivated fallow plot were greater than 20 imaduring each of 10 storms. Average annual rainfall of 1314 mm and rainfall erosion index of 6315 MJmm (ha h)-1 during 1958 to 1976 for the 303-square kilometer Pigeon Roost Watershed near HollySprings, Mississippi illustrated the high erosivity of rainfall. Conservation tillage cropping systems forcom (grain and silage), soybean, cotton, and sorghum from 1974 to 1990 at Holly Springs effectivelycontrolled erosion, especially as compared to conventional-till. Soil losses from agricultural landpreviously under conventional-till were dramatically reduced. Cropping and management factor (SLR)values derived from selected large storms provided good estimates of annual SLR values for use in theuniversal soil loss equation. | K. C. McGregor R. F. Cullum C. K. Mutchler( Agricultural Engineer, Agricultural Engineer, and Research Hydraulic Engineer (Collaborator), respectively, withthe USDA-ARS, National Sedimentation Laboratory, Oxford, MS, USA ) | 2000 | International Journal of Sediment Research2000，15，2： | 6 |
| 2 | EFFECTIVE DISCHARGE CALCULATION GUIDE显示文摘This paper presents a procedure for calculating the effective discharge for rivers with alluvial channels. An alluvial river adjusts the bankfull shape and dimensions of its channel to the wide range of flows that mobilize the boundary sediments. It has been shown that time-averaged river morphology is adjusted to the flow that, over a prolonged period, transports most sediment. This is termed the effective discharge. The effective discharge mayo be calculated provided that the necessary data are available or can be synthesized. The procedure for effective discharge calculation presented here is designed to have general applicability, have the capability to be applied consistently, and represent the effects of physical processes responsible for determining the channel. dimensions. An example of the calculations necessary and applications of the effective discharge concept are presented. | D. S. BIEDENHARN,C. R. THORNE, P.J.SOAR. ,R.D.HEY, and C. C. WATSONS 1 Engineer, U.S. Army Corps of Engineers, Waterways Experiment Station, Vicksburg, MS 39180, USA. 2Professor School of Geography, University of Nottingham, Nottingham NG7 2RD, UK. 3 Prof | 2001 | International Journal of Sediment Research2001，16，4： | 5 |
| 3 | MATHEMATICAL MODELS FOR LIQUID-SOLID TWO-PHASE FLOW显示文摘The governing equations, interphase actions, constitutive relations and turbulence closures of the twofluid model and diffusion model for the liquid-solid two-phase flow are studied in this paper. The pressure actions in and between two phases are analyzed, and the governing equations of the two-fluid model are conveniently closed by adding the interphase pressure-difference force into the pressure terms of momentum equations. The constitutive relations for the liquid-solid mixture in the diffusion model are given by the models of Newtonian fluid and Bingham fluid, and the Bingham relation of shear stress and deformation rate for the single-directional shear flow of the mixture is extended to a general form for the multi-directional shear flow. The equation for the interphase velocity difference, which is used to close the generalized diffusion model, is derived from the momentum equations of two-fluid model and then simplified to more useful forms. For the turbulent flow, the mean movement equations of the two-fluid model and diffusion model are derived by using Reynolds averaging method. The closure techniques for the mean movement equations on the levels of zero-order turbulence model and κ-ε turbulence model are suggested. This paper presents the general basis of the mathematical models, which is to be followed by their validations and applications in the near future. | Weiming Wu and Sam S.Y. Wang National Center for Computational Hydroscience and Engineering, The University of Mississippi, MS 38677, U.S.A. | 2000 | International Journal of Sediment Research2000，15，3： | 5 |
| 4 | PROCESSES OF EPHEMERAL GULLY EROSION显示文摘The formation of ephemeral gullies can significantly increase soil loss from agricultural lands and severely impact farm productivity. Erosion prediction technology and conservation management techniques would be greatly improved if the contribution from ephemeral gullies could be more accurately quantified. Field research in Mississippi, U.S.A. and Spain has revealed three categories of ephemeral gullies. Classic ephemeral gullies formed by concentrated flow erosion from runoff occurring within the same field. Drainage ephemeral gullies formed by concentrated flow erosion from runoff originating from areas upstream of where the gully occurs. Discontinuity ephemeral gullies formed in areas where management practices have created a sudden change in slope, such as field boundaries adjacent to roads.Despite the large differences in climate, watershed size, hydrology, and geography, the ephemeral gullies observed in Spain were morphologically similar to those in Mississippi. Using an experimental flume,ephemeral gully erosion proceeded primarily through bed incision, gully widening, and bank steepening,and total sediment load depended upon whether the flow was detachment- or transport-limited. | Javier Casali(Department of Projects and Rural Engineering, Public University of Navarra, 31006 Pamplona, Navarra, Spain) SeaN J. Bennett(National Sedimentation Laboratory, USDA-ARS, P.O. Box 1157, Oxford, MS 38655, USA)Kerry M. Robinson(Plant Science and | 2000 | International Journal of Sediment Research2000，15，1： | 4 |
| 5 | A Study of the Characteristics of Consumers' Behavior under the Web Environmen显示文摘The development of Internet has made shopping online possible. But while we are focusing ourselves on the environment design, plan for the information structures and items or business scales, another important factor has been ignored, that is, the changes of the characteristics of consumers behavior under the web environment. Because we are not able to make the exact online marketing strategy according to the changes of consumers behavior, and although many online shops have been opened, we are not able to get big sales. This article emphasises the analysis of the environment for on line transactions, attampts to investigate the basic modes for information movement and on line shopping of those consumers under the web environment, study the influence on consumers brought by Internet, the shopping styles and their characteristics. | LIU Li (Department of Management Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210003, P.R.China)Biography:\ LIU Li (1958-), male, from Hunan Province, received MS degree in management from Northeast University in 1990, associ | 2001 | The Journal of China Universities of Posts and Telecommunications2001，8，1： | 3 |
| 6 | OPTIMAL MODE OF SEDIMENT TRANSPORT BY SHALLOW FLOWS IN UPLAND AREAS显示文摘Soil erosion and sediment movement are serious problems of upland areas of a watershed. In these areas,most of the eroded sediment is transported in overland flows; either in shallow or in concentrated flowsituations. These flows are usually associated with nonlinear waves, generally known as 'roll waves' inthe hydraulic engineering literature. Under suitable hydraulic conditions, these waves contain a significantfraction of the total kinetic energy of the flow regime. Hence, the waves act as the primary energy sourcein transporting eroded sediment in shallow flows on steep slopes. Our laborat0ry experiments undercontrolled condition suggest that modulation of the roll waves is effected by the addition of increasingamouflts of sediment in the flow. The optimal condition in the sediment transport rate is reached whenmost of the available wave energy is consumed in carrying the sediment. A related set of experiments ongravitational flows of dry granular material show that the evolving scales of sediment waves are intrinsicto the transport mechanism of the solid phase. | D. PAL S. N. PRASAD (Department of Civil Engineering, University of Mississippi, University, MS 38677, USA.) M. J. M. ROMKENS(USDA ARS National Sedimentation Laboratory, Oxford, MS 38655, USA.) | 2000 | International Journal of Sediment Research2000，15，2： | 3 |
| 7 | Finger pulp reconstruction with free dorsoulnar artery perforator ( DUAP) flap显示文摘 | Simsek T Engin MS Aslan 0 | 2011 | J Reconstr Microsurg2011，27，9： | 1 |
| 8 | Expression profiling of ascorbic acid-related genes during tomato fruit develop- ment and ripening and in response to stress conditions显示文摘 | Ioannidi E KaIamaki MS Engineer C | 2009 | J Exp Bot2009，60，： | 1 |
| 9 | SEDIMENT YIELD-SURFACE TOPOGRAPHY RELATIONSHIPS FOR SELECTED MISSISSIPPI SOILS显示文摘Microtopography is an important surface characteristic of upland areas that affect erosion processes of detachment, transport, and runoff Yet, little quantitative information is available about the relationship between surface microtopography and sediment yield. A laboraory rainfall simulation study was conducted to determine for four different erosion susceptible soils the changes in surface microtopography and sediment yield during a series of 6 to 8 rainstorms of 0.75 h duration and 60 mm h-1 intensity each. The soils chosen were the Ap-materials of a Grenada sil (Glossic Fragiudalfs), Atwood sil (Typic Paleudalfs), and a Forestdale sicl (Typic Ochraqualfs), as well as the C-material, a Glauconitic sediment, of a Ruston sil (Typic Paleudalfs). Soil beds were prepared in a flume with a seedbed-like surface condition. Before all and after each rainstorm, the surface microtopography was determined using a laser microreliefmeter. Microtopography, expressed in terms of the mean local topographic gradient, and runoff data indicate a very similar pattern among the four soils. The data show an initially rapid increase in the sediment concenttation, which reached quickly a maximum and then gradually decreased to a near constant value at the end of the storm series. Sediment yield followed closely the sediment concentration trend due to a near constant runoff rate. Surface microtopography changed rapidly during the first rainstorm but then decreased more gradual to an approximate constant value for most of the later rainstorms in the sequence. Three distinct phases in the sediment yieldmicrotopography relationship are recognized: (1) a preponding phase, (2) a post ponding-increased sediment yield phase, and (3) a post ponding-decreased sediment yield phase. These phases reflect changes in the relative importance of soil erosion processes of roughness dissipation, rill development,and soil surface matrix stabilization. | M. J. M. ■(USDA-ARS National Sedimentation Laboratory, Oxford, MS 38655)K. Helming (ZALF, Muencheberg, Germany)S. N. Prasad(Dept. of Civil Engineering, University of Mississippi, University, MS 38677 | 2000 | International Journal of Sediment Research2000，15，1： | 1 |
| 10 | Finger pulp reconstruction with free dorsoulnar perforator (DUAP) flap显示文摘 | Simsek T Engin MS Asian O | 2011 | J Reconstr Microsurg2011，27，9： | 1 |
| 11 | Transscleral fixation of a single piece hydrophilic foldable acrylic intraocular lens 显示文摘 | Taskaplili M Gulkilik G Engin G Kocabora MS Yilmazli C Ozsutcu M | 2007 | Can J Ophthalmol2007，42，2： | 1 |
| 12 | End-to-end microvascular anastomosis in the rat carotid artery using continuous horizontal mattress sutures显示文摘 | Sim?ek T Eroglu L Engin MS | 2006 | J Reconstr Microsurg2006，22，8： | 1 |
| 13 | Finger pulp reconstruc- tion with free dorsoulnar artery perforator(DUAP) flap 显示文摘 | Simsek T Engin MS Aslan O | 2011 | J Reconstr Microsurg2011，27，9： | 1 |
| 14 | Finger pulp Recon- struction with free dorsoulnar artery perforator (DUAP) flap 显示文摘 | Simsek T Engin MS Aslan O | 2011 | J Reconstr Microsurg2011，27，9： | 1 |
| 15 | A physically-based integrated numerical model for flow,upland erosion,and contaminant transport in surface-subsurface systems显示文摘This paper presents a physically-based integrated hydrologic model that can simulate the rain-fall-induced 2D surface water flow, 3D variably saturated subsurface flow, upland soil erosion and transport, and contaminant transport in the surface-subsurface system of a watershed. The model couples surface and subsurface flows based on the assumption of continuity conditions of pressure head and exchange flux at the ground, considering infiltration and evapotranspiration. The upland rill/interrill soil erosion and transport are simulated using a non-equilibrium transport model. Contaminant transport in the integrated surface and subsurface domains is simulated using advection-diffusion equations with mass changes due to sediment sorption and desorption and exchanges between two domains due to infiltration, diffusion, and bed change. The model requires no special treatments at the interface of upland areas and streams and is suitable for wetland areas and agricultural watersheds with shallow streams. | HE ZhiGuo1 & WU WeiMing2 1 Department of Hydraulic and Ocean Engineering, Zhejiang University, Hangzhou 310058, China 2 National Center for Computational Hydroscience and Engineering, University of Mississippi, Oxford, MS 38677, USA | 2009 | Science China(Technological Sciences)2009，52，11： | 0 |
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