One of the most frequently used methods in image processing is thresholding. This can be a highly efficient means of aiding the interpretation of images. A new technique suitable for segmenting both gray-level and color images is presented in this paper. The proposed approach is a multithresholding technique implemented by a Principal Component Analyzer (PCA) and a Kohonen Self-Organized Featur...

Objective: Mesenteric ischaemia is an uncommon (,1%) but serious complication of cardiac surgery associated with a mortality .50%. Predictors of this complication are not well defined, and diagnosis can be difficult and prompt surgical intervention can be lifesaving. Methods and results: In a retrospective case-note analysis from May 1994 through to May 2000, we identified mesenteric ischaemia ...

This study investigates the validity of purchasing power parity (PPP) hypothesis as a long run equilibrium condition for thirteen Asia Pacific economies using a generalized error correction model. The results of the generalized dynamic specification appear to support PPP for more countries than do standard tests for unit roots. Out of the thirteen bilateral exchange rates, evidence of PPP is fo...

In this paper we present a heuristic to reconstruct nonsmooth curves with multiple components. Experiments with several input data reveals the effectiveness of the algorithm in contrast with the other competing algorithms.  2001 Elsevier Science B.V. All rights reserved.

Mercury emission and speciation of coal-fired power plants in China S. Wang, L. Zhang, G. Li, Y. Wu, J. Hao, N. Pirrone, F. Sprovieri, and M. P. Ancora Department of Environmental Science and Engineering, and State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China CNR – Institute of Atmospheric Pollution Research, Via Salaria Km 29....

Ð Collaborative learning of visual information with computers can be particularly beneficial for acquiring complex and abstract knowledge. This article describes a computer-supported collaborative visual learning environment called TurtleGraph that was designed to assist learners in capturing the concept of recursion as well as recursive programming skills. In this distributed learning environm...

The accumulation of damage within a structure due to service loading or environmental conditions is a random phenomenon. Continuum damage mechanics (CDM) enables macroscopic manifestations of damage to be related to microscopic defects and discontinuities present within a material. This permits margins of safety to be assessed prior to the time at which damage becomes visible or detectable. Und...

Three major depositional basins (the Gdansk, Bornholm and Eastern Gotland basins) of the Baltic Proper, which together account for .50% of the depositional areas in the entire Baltic Sea, have accumulated increased amounts of sediment and organic carbon during the last 50 years, as is shown in Pb-dated sediment cores. The shallow Arkona Basin has had constant accumulation rates and rate increas...