We consider optimal control problems for the flow of gas or fresh water in pipe networks as well as drainage or sewer systems in open canals. The equations of motion are taken to be represented by the nonlinear isothermal Euler gas equations, the water hammer equations, or the St. Venant equations for flow. We formulate model hierarchies and derive an abstract model for such network flow proble...

thin-walled hollow steel columns, either circular or box shaped, are commonly used as piers in bridges. recent earthquakes, e.g. hyogoken-nanbu or kobe 1995, on the other hand have shown that these columns are vulnerable to damage when subjected to earthquake loading. this paper presents a new innovative thin-walled hollow steel column fabricated of corrugated plates, “thin-walled steel columns...

In this paper, a novel corrugated structure at the edges of the Vivaldi substrate is presented. Compared with the Vivaldi antenna without corrugated structure, the new structure has a better radiation pattern. While compared with the traditional corrugated structure, the new structure has a better front-to-back ratio (F/B ratio). Properly chosen thickness and dielectric constant of substrate en...

In this paper, we perform surface plasmon-coupled emission studies on Rhodamine 6G molecules embedded in a corrugated structure of a thin film composed of fluorinated silica particles, and a binding medium. Our results show enhancements of photoluminescence due to surface corrugation. By varying the size of the fluorinated silica nanoparticles we were able to control the surface correlation len...

Drainage systems have been routinely used since the early modern surgical era [1], on the grounds that body fluids and necrotic material offer an optimal growth medium for microorganisms [2]. They are also thought to decrease postoperative pain and wound infection. Suction is the preferred modality: a 1988 study showed that a suction tube placed beneath the rectos sheath was significantly super...

The deterministic field scale model DRAINMOD was tested in an experiment on subsurface pipe drainage in the Veneto region, in an environment of NE Italy characterised by the presence of a shallow water table in a flat area. The objective was to determine whether a minimal set of field data would suffice to use DRAINMOD for predictive purposes. The measured water table depth and drain outflow fr...

We present a method of fabricating Ge-doped SiO2 fibers with corrugations around their full circumference for a desired length in the longitudinal direction. The procedure comprises three steps: hydrogenation of Ge-doped SiO2 fibers to increase photosensitivity, recording of Bragg gratings with ultraviolet light to achieve modulation of refractive index, and chemical etching. Finite-length, rad...

Thin-walled hollow steel columns, either circular or box shaped, are commonly used as piers in bridges. Recent earthquakes, e.g. Hyogoken-Nanbu or Kobe 1995, on the other hand have shown that these columns are vulnerable to damage when subjected to earthquake loading. This paper presents a new innovative thin-walled hollow steel column fabricated of corrugated plates, “thin-walled steel columns...

In this paper, we investigate a corrugated mm-scale capillary as a compact accelerating structure in a drive – witness acceleration scheme, and suggest a methodology to measure acceleration of a witness bunch. Two typical measurements and the energy gain in a witness bunch as a function of the distance between bunches are discussed. A corrugated capillary is considered as an accelerator/deceler...