Strain analysis of moving objects using a Fourier transform grid method

There is no good method to measure the shape and the strain distributions of a structure changing with time. We have previously proposed the Fourier transform grid method (FTGM) to measure the three-dimensional shape and surface strain distributions of stationary objects by analysing the two-dimensional grating images recorded with two cameras. In the stereoscopic method, it is very important to determine the accurate geometric parameters of the camera system. In this paper, the positions and the directions of cameras are accurately determined using the FTGM applied to images of a reference object on which a two-dimensional grating is drawn. Applications for analysing shape and strain distributions of vibrating rubber plates and a moving human skin are shown.     

Developing maintainable expert systems using case-based reasoning

Abstract: Maintainability problems associated with traditional software systems are exacerbated in rule-based systems. The very nature of that approach — separation of control knowledge and data-driven execution — hampers maintenance. While there are widely accepted techniques for maintaining conventional software, the same is not true for rule-based systems. In most situations, both a knowledge engineer and a domain expert are necessary to update the rules of a rule-based system. This paper presents, first, an overview of the software engineering techniques and object-oriented methods used in maintaining rule-based systems. It then discusses alternate paradigms for expert system development. The benefits of using case-based reasoning (from the maintenance point of view) are illustrated through the implementation of a case-based scheduler. The main value of the scheduler is that its knowledge base can be modified by the expert without the assistance of a knowledge engineer. Since changes in application requirements can be given directly to the system by the expert, the effort of maintaining the knowledge base is greatly reduced.     

Bioactivity of antifouling paints based on organotin toxicants

This paper discusses the bioactivity of antifouling paints based on organotin toxicants, such as tributyltin fluoride (TBTF) and triphenyltin fluoride (TPTF). These compounds were used alone or mixed as the main toxicant in formulations. The use of TPTF or mixtures of TPTF and TBTF, with vinyl binders, led to paints with satisfactory bioactivity during a 24 months immersion period. With the same binders, TBTF alone provided only 12 months of antifouling protection. The correlation coefficients calculated from the fouling attachment values and the rosin content in the binder showed that the bioactivity of the tested formulations depended on the solubility of the toxicant in sea water and on the composition and solubility of the binders.     

Recovering spectral data from natural scenes with an RGB digital camera and colored filters

Many spectral‐recovery methods using RGB digital cameras assume the underlying smoothness of illuminant and reflectance spectra, and apply low‐dimensional linear models. The aim of the present work was to test whether a direct‐mapping method could be used instead of a linear‐models approach to recover spectral radiances and reflectances from natural scenes with an RGB digital camera and colored filters. In computer simulations, a conventional RGB digital camera with up to three colored filters was used to image scenes drawn from a hyperspectral image database. Three measures were used to evaluate recovery with the direct‐mapping method: goodness‐of‐fit, root‐mean‐square error, and a color‐difference metric. It was found that with two and three filters both spectral radiances and reflectances could be recovered sufficiently accurately for many practical applications. With little increase in computational complexity, an RGB camera and a few colored filters can provide significantly better recovery of natural scenes than an RGB camera alone. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 352–360, 2007     

阳泉市煤矿采空区地质因素对公路的破坏

介绍了阳泉市煤矿采空区对公路建设所造成的危害，对其上覆岩层变形破坏的地质因素及其破坏机理作了分析，指出应该采取各种措施减少对公路的破坏。     

Stress distribution on [100] Si wafer mapped by novel I-V analysis of MOS tunneling diodes

The current-voltage (I-V) characteristics of metal-oxide-semiconductor tunneling diodes distributed over a 3-in Si wafer were analyzed to investigate the stress distribution on the wafer. Generally, the substrate injection saturation current (J/sub sat/) decreases as the gate injection leakage current (J/sub g/) increases, the latter being dominated by oxide thickness via a trap related mechanism. A universal curve to fit all analyzed data was found and it is suggested that devices with extremely high (low) J/sub sat/ at a given J/sub g/ should be located in areas of the silicon lattice with relatively high external compressive (tensile) stress because of the stress-induced bandgap variation effect. The mapped locations of the highly stressed devices on a 3-in [100] Si wafer correspond to the patterns of slips caused by thermal stress during rapid thermal processing, as described in previous reports.     

Temperature dependence of hydrogenated amorphous silicon thin-film transistors

The temperature dependence characteristics of hydrogenated amorphous silicon thin-film transistors were investigated. The results indicate that as the temperature was increased, the threshold voltage and the field-effect mobility were first increased, and then decreased, which may be controlled by different mechanisms at low and high temperatures. In addition, if the temperature was higher than 420 K, the Fermi level was promoted to the degenerate-like states, the current channel always existed due to the temperature effect, and the threshold voltage became negative.