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The model tree (MT) approach, a data mining technique used to analyse relationships between input and output variables in a disordered and large database, was adopted in this study to predict sediment discharge with field measurement data. The derived models were analysed for accuracy according to the goodness of fit based on training, testing, and modelling processes. When the flow velocity, depth, water surface slope, channel width, and median bed material were selected as the river's system variables, the model results of sediment discharge resembled the measured values. The results demonstrate that developing and using the sediment discharge estimation with the MT constitutes the most effective method if long-term sediment data are of sufficient validity. [ABSTRACT FROM AUTHOR]

In this paper, we extend two important notions, weighted average method and Mann's iterative method, in the study of convex feasibility problem for general maps defined on p-uniformly convex metric spaces. Then we prove the Δ-convergence theorems for the weighted average sequence and the Mann's alternating sequence in p-uniformly convex metric spaces. [ABSTRACT FROM AUTHOR]

The results of an experimental study on the flow characteristics around a groin structure of various geometries and permeabilities are presented. The impermeable rectangular, the permeable pile, and the triangular-shaped groins are considered. The velocity fields were observed using large-scale particle image velocimetry, whereas the maximum velocities were measured using an acoustic Doppler velocimeter. An increased velocity at the groin tip and a broad range of the recirculation zones were observed for the impermeable rectangular groin. For the permeable pile groin, the velocity at the groin tip, the vortex strength, and the scale of the recirculation zone tended to decrease as the openings between the piles increased. Also, the triangular-shaped groin formed narrower and longer recirculation zones compared with the permeable pile groin of identical cross-sectional flow area. These quantitative findings on the flow patterns for groins of various geometries and permeabilities are practically important to design and evaluate their performance in field applications. [ABSTRACT FROM PUBLISHER]

Dye-sensitized solar cells (DSSCs) were prepared with a poly(ethylene glycol) (PEG) electrolyte using various metallophthalocyanines (MPcs) as an additive. The DSSC device using MPcs has higher power conversion efficiency than that without MPcs, due to decrease of electron transfer distance by the interface adsorption between TiO2 film and PEG electrolyte. The best result on power conversion efficiency was 4.18% in DSSC device using InOHPc. The open-circuit voltage (Voc) was 0.70 V, the short-circuit current density (Jsc) was 10.20 mA/cm2, and the Fill Factor (FF) was 0.58. The addition of MPcs as an additive is useful to improve the performances of DSSC devices such as Voc, Jsc, and power conversion efficiency. [ABSTRACT FROM AUTHOR]

The dye-sensitized solar cell devices using PEDOT:PSS films as counter electrodes have the lower production cost and more simple fabrication process than devices using Pt counter electrode. To enhance the power conversion efficiency of devices, we fabricated DSSC devices using thermal treated poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) as counter electrodes. The power conversion efficiency of DSSC device using a counter electrode based PEDOT:PSS film treated at 45°C for 720 min achieved a value of 3.22%. [ABSTRACT FROM AUTHOR]

A response from Joongu Kang, Hongkoo Yeo, Sungjung Kim and Un Ji to the letter to the editor regarding their article "Permeability effects of single groin on flow characteristics," in a 2011 issue is presented.