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This paper introduced an XML-based unified user interface system which implemented under Sun Microsystems's J2EE architecture. It is a multiple user interface system that user can access through Web browsers, PDA, and even cellular phones. First, we will dilate the main idea of this system and we will introduce XML technology and J2EE architecture that used in this system, and then a brief introduction in WAP (Wireless Application Protocol) technology. Second, we will introduce our related work. Third, we will introduce our work in the system. Finally, express our conclusions, and future work.

This paper presents three approximate Riemann solver schemes, namely: the flux vector splitting (FVS), the flux difference splitting (FDS), and the Osher scheme. Originally used to solve the Euler equations in aerodynamic problems, these Riemann solvers based on the characteristic theory are used in the finite volume method (FVM) for solving the two-dimensional shallow water equations. The three solvers are compared in this paper according to theoretical development, difference schemes, practical applications to shock wave problems, and sensitivity analysis on the computational stability of the methods. The effects of changes in bed elevations on the solutions are also investigated. Comparison of numerical and analytical solutions indicates that very good agreement can be obtained by all three approximate Riemann solvers. Differences in accuracy, computer time, and numerical stability among the three schemes are not significant. For practical purposes, all of them can satisfactorily simulate the hydraulic phenomena in subcritical and supercritical flows as well as in smooth and discontinuous flows, especially shock wave modeling. These solvers are useful for studying levee failure or dam break due to extreme flood events, or the sudden opening or closing of sluice gates in a channel.

The paper presents a two‐dimensional unsteady‐flow model, RBFVM‐2D, based on the finite‐volume method with a combination of unstructured triangular and quadrilateral grids in a river‐basin system. The attractive feature of this model is that it calculate of the mass and momentum flux across each side of elements as a Riemann problem, which is solved using the Osher scheme. This feature enables this model to deal with the wetting and drying processes for flood‐plain and wetland studies, dam breaking phenomena involving discontinuous flows, subcritical and supercritical flows, and other cases. The computations of tributary inflows and regulated flows through gates, weirs, and culverts or bridges are also included. Sample applications of this model to two dam‐break problems showed fairly satisfactory results. Also, this model was applied to a portion of the Kissimmee River Basin in Florida for flow simulations and the results agreed well with the field and laboratory data in a physical‐model study of this ri...

The use of derived distributions to predict flood frequency is relatively new and requires refinement and improvement. This paper reports another effort to obtain and test a derived flood‐frequency distribution, applicable to small watersheds in which overland flow is considered an important runoff component. Watersheds are conceptualized as first‐order streams with two symmetrical planes. The kinematic wave theory is used to obtain expressions to compute peak discharge and time to peak, as functions of effective precipitation variables and watershed parameters, for four different runoff cases. These cases are formulated according to whether or not there is concentration on the overland flow plane and in the stream. Some of these expressions are subsequently improved using regression analysis and kinematic wave simulated results. The probabilistic model for rainfall characteristics and the infiltration model are taken from results presented previously in the literature for other derived flood‐frequency di...

A 76-year-old man with previous sigmoid colon resection for adenocarcinoma had low back pain for 2 months. Whole-body bone scintigraphy showed multiple focal Tc-99m methylene diphosphonate (MDP)-avid lesions in both rib cages and 3 lumbar vertebrae, indicating metastases. F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) imaging was performed for further evaluation of this possible metastatic disease and demonstrated the lumbar and costal metastases and several hypermetabolic areas in the pelvic bones, multiple thoracic vertebrae, both shoulders, and the right femur. Histopathologic examination of the right-sided iliac crest, however, revealed multiple myeloma.

Electrochemical and ellipsometric measurements of the effect of octylamine addition to potassium hydrogen phthalate (KHP) solution on the formation of passive films on iron were made. It w...

The physical basis of the linkage between magnitude and timing of channel flow hydrographs and drainage network morphometry is reviewed. Small Hortonian and structurally Hortonian networks are analysed using numerical runoff simulation. For Hortonian networks the variability of the geometry of individual channels and subcatchments within each Strahler order has generally little effect upon the overall character of the hydrograph in channels of higher order. If the network is also structurally Hortonian, the analysis of the simultaneous formation, travel, and concentration of the hydrographs in all channels of the network can be simplified to a sequence of one representative hydrograph per channel order. This approach is used in this study. Three major runoff processes control the flow hydrograph characteristics: the overland flow process which determines the water supply to the drainage network; the channel flow process which translates the hydrograph in space and time; and the drainage network process which concentrates and magnifies the flow at the junctions of the drainage network. Functional relations for the hydrograph peak, timing, and flow velocity are presented. For a given uniform rainfall and infiltration rate, the peak of the channel flow hydrograph is shown to increase geometrically with channel order, and its magnitude is directly related to the bifurcation ratio. The travel time of the peak also increases geometrically with channel order, and it is directly related to the channel length ratio over velocity ratio. The flow velocity of the peak changes in a downstream direction as a function of the bifurcation and slope ratio. It was also found that for negligible channel storage the channel flow and drainage network processes do not contribute significantly to the observed nonlinear response of a watershed to precipitation.

Two of the distributions most widely used in flood magnitude modeling are the Gumbel type 1 extreme-value distribution and the log Pearson type 3. These represent two fundamentally different assumptions about distribution tail behavior in that extreme events from the log Pearson type 3 distribution follow the Gumbel type 2 extremal distribution. This paper compares these two assumptions by comparing flood predictions by the type 1 and type 2 models. For the Gumbel type 1 distribution the ratio of xn1 the magnitude of a flood with a return period n1, to xn2, the magnitude for a shorter return period n2, can be estimated by an upper bound which is In n1/ln n2. It is shown that the ratio of xn1/xn2 from the type 2 distribution is always greater than that from the type 1, approximated by (n1/n2)1/k. An analysis of flow data collected in the United States indicates that in the majority of cases the best fitting type 2 distribution does not have a finite variance and often not even a finite mean. The impact of this on statistical data analysis is discussed.

Two different types of meander patterns are found on the sediment beds of straight alluvial channels with nonerodible banks. The first type occurs when the Froude number of the flow is close to 1 and the ratio between the depth and the width of the flow is within a certain range. This pattern probably results from surface waves on the water. The second type of pattern has alternating scour holes and occurs predominantly when water is flowing between rough banks. It is shown how this pattern can be caused by the difference between the shear stresses at the two sides of the flow cross section.

Critical conditions for the occurrence of snow avalanches are first reviewed and summarized. Physical descriptions of slab avalanche, powder avalanche and mature powder avalanche are given. A two-dimensional dynamic model based on a fluid mechanics principle to describe snow avalanche is introduced. The vertical distribution of pressure forces above ground are estimated from this model based on some of the empirical relationships determined by A. Voellmy [18]. Finally, the estimations of the anticipated forces by a snow avalanche on a proposed bridge are given.

In order to promote cultural and scientific exchange, the American Geophysical Union has invited a delegation from the Society of Hydraulic Engineers of the People's Republic of China to visit the United States. This team, led by Pao-Ling Li, Deputy Minister of the Ministry of Water Conservancy and Electric Power, will probably visit the U.S. Weather Service, the U.S. Geological Survey, the Bureau of Reclamation, the U.S. Army Corps of Engineers, California Institute of Technology, Colorado State University, the University of Iowa, Harvard, and the Massachusetts Institute of Technology during May and June 1980. This tour reciprocates a visit to the People's Republic of China by a team of American engineers and scientists in September and October 1978. Our team was led by J. F. Kennedy, Director of the Institute of Hydraulic Research at the University of Iowa, and included C. L Chiu, Professor of Civil Engineering, University of Pittsburgh; R. Clark, Associate Director of the U.S. Weather Service; J. E. Glover, Chief of the River Division, Waterways Experiment Station, U.S. Army Corps of Engineers; A. S. Harrison, Head of the Technical Engineering Branch, Mississippi River Division, U.S. Army Corps of Engineers; D. Louie, Chief Hydraulic Engineer, Harza Engineering Company; N. Matalas, Staff Hydrologist, Water Resources Division, U.S. Geological Survey; C. F. Nordin, Water Resources Division, U.S. Geological Survey; E. L. Pemberton, Head of the Sedimentation Section, U.S. Bureau of Reclamation; A. R. Robinson, Staff Scientist, Science and Education Administration, U.S. Department of Agriculture; and myself.