Corresponding regions for shadow restoration in satellite high-resolution images

ABSTRACT

High spatial resolution images available by satellites such as Ikonos, Quickbird, and WorldView-2 provide more information for remote sensing applications, such as object detection, classification, change detection, and object mapping. The presence of shadow reduces the amount of information that can be extracted and consequently makes these applications more difficult or even impossible. In this article, a shadow restoration approach for high-resolution satellite images is proposed. The approach detects the shadow area and segments the image into regions according to the land surface type. Then, shadow restoration is carried out for each region based on the degree of correspondence between shadow and neighbouring non-shadow regions. The proposed approach is applied to study areas from Ikonos and WorldView-2 satellite images. A comparison to the standard approaches for shadow restoration is performed, and an accuracy assessment is carried out by visual inspection and land-cover classification. The results show that the enhanced shadow regions using the proposed approach have better appearances and are highly compatible with their surrounding non-shadow regions. In addition, the overall accuracy is higher than those of the standard approaches.     

Voice Data Entry (VDE) training and Implementation Strategies

Current effort at Kennedy Space Center (KSC) involves implementation of voice data entry in the thermal Tile Processing System (TPS). Large amounts of data collection and recording along with the advancement in voice recognition and speech synthesis justified the introduction of a voice data entry system in support of TPS.

This paper presents a training and an implementation strategies for the VDE System in TPS at KSC. Training Strategies are tailored to different levels of the target population with varying objectives for the training sessions. Training scenarios and training manuals are designed to support the objectives of each session. A unique feature of the VDE is the fact that the “system” also needs to be trained for specific users.

Implementation strategy calls for parallel implementation for the current manual system over a period of four consecutive missions. This would be followed by gradual phasing out of the current manual system and phasing in of the VDE system over a span of three missions.

The methodologies used and the developed strategies can be used for the introduction of new technologies in general, and that related to voice and speech recognition in particular.     

Objective Site Characterization Using Clustering of Piezocone Data

Cluster analysis is a statistical method for grouping similar mathematical data sets and is used herein for delineating geostratigraphy from piezocone penetration test data. In terms of site characterization, clustering is an improvement over other statistical methods because no preliminary estimation of the inherent groups within the analyzed data is needed, and no overlapping is permitted between identified clusters. Clustering can accommodate single or multivariables and no data filtering is required. Its application to defining stratigraphic interfaces is illustrated using five case studies with layered profiles. Clustering is able to detect major changes within the stratigraphy not apparent by visually examining the trends of piezocone data or by available cone soil classification methods.     

Association Equation of State for Hydrogen-Bonded Substances

An association equation of state (AEOS) has been proposed for hydrogen-bonded compounds. To obtain this AEOS, the compressibility factor was assumed to consist of two parts: the physical part due to physical interactions of molecules; and the chemical part due to molecular association by hydrogen bonding of molecules. The physical part of the compressibility factor was represented by the MMM EOS for non-polar compounds proposed by Mohsen-Nia et al., Fluid Phase Equilib. 206 , 27-39 (2003), and the chemical part of the compressibility factor was deduced by proposing a molecular association model of infinite series.     

Effect of FGM core on dynamic response of a buried sandwich cylindrical shell in poroelastic soil to harmonic body waves

The two-dimensional dynamic interaction of progressive plane seismic waves with an arbitrarily thick, isotropic, and functionally graded cylindrical shell of infinite extent embedded in a boundless fluid-saturated porous elastic medium is investigated. The inhomogeneous shell is approximated by a laminate model, for which the solution is expected to gradually approach the exact one as the number of layers increases. Continuity of the displacement and stress components at the interfaces of neighboring layers is applied to form a system global transfer matrix, ultimately leading to determination of the modal scattering and transmission coefficients. The analytical results are illustrated with numerical examples in which an air-filled steel–zirconia FGM shell, buried in a water-saturated Ridgefield Sandstone formation, is insonified by fast compressional or shear waves at normal incidence. The effects of material compositional gradient and FGM layer thickness on the basic dynamic field quantities are evaluated and discussed. Limiting cases are considered and good agreements with the solutions available in the literature are obtained.     

Role of nano‐size SiO2 additive on the thermal behavior of cyanoacrylate nanocomposite

Nowadays, solvent‐free, one‐part cyanoacrylate adhesive is widely used in medicine and dentistry. According to a literature survey done by the authors, there are few papers concentrated on the role of nano‐sized particles on the thermal behavior of cyanoacrylate glue. Thus the main goal of the current research focused on clarifying the role of nano‐sized SiO₂ on the thermal behavior of cyanoacrylate. Thermal behavior of all materials including cyanoacrylate and its nanocomposites was studied by using Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) methods. The results of DSC analysis showed that an increase in the amount of nano‐sized SiO₂ results in decreases in the duration of cyanoacrylate curing, energy release during polymerization, and incubation time of polymerization. Furthermore, the results of TGA tests illustrated that the weight loss of cyanoacrylate strongly depends on the contents of both caffeine and SiO₂. In fact, an increase in nano‐sized SiO₂ content increases the degradation temperature of cyanoacrylate. J. VINYL ADDIT. TECHNOL., 2010. © 2010 Society of Plastics Engineers     

Analysis of MTHFR and MTRR Gene Polymorphisms in Iranian Ventricular Septal Defect Subjects

Ventricular septal defect (VSD) is one of the most common types of congenital heart defects (CHD). There are vivid multifactorial causes for VSD in which both genetic and environmental risk factors are consequential in the development of CHD. Methionine synthase reductase (MTRR) and methylenetetrahydrofolate reductase (MTHFR) are two of the key regulatory enzymes involved in the metabolic pathway of homocysteine. Genes involved in homocysteine/folate metabolism may play an important role in CHDs. In this study; we determined the association of A66G and C524T polymorphisms of the MTRR gene and C677T polymorphism of the MTHFR gene in Iranian VSD subjects. A total of 123 children with VSDs and 125 healthy children were included in this study. Genomic DNA was extracted from the buccal cells of all the subjects. The restriction fragment length polymorphism polymerase chain reaction (PCR-RFLP) method was carried out to amplify the A66G and C524T polymorphism of MTRR and C677T polymorphism of MTHFR genes digested with Hinf1, Xho1 and Nde1 enzymes, respectively. The genotype frequencies of CC, CT and TT of MTRR gene among the studied cases were 43.1%, 40.7% and 16.3%, respectively, compared to 52.8%, 43.2% and 4.0%, respectively among the controls. For the MTRR A66G gene polymorphism, the genotypes frequencies of AA, AG and GG among the cases were 33.3%, 43.9% and 22.8%, respectively, while the frequencies were 49.6%, 42.4% and 8.0%, respectively, among control subjects. The frequencies for CC and CT genotypes of the MTHFR gene were 51.2% and 48.8%, respectively, in VSD patients compared to 56.8% and 43.2% respectively, in control subjects. Apart from MTHFR C677T polymorphism, significant differences were noticed (p < 0.05) in C524T and A66G polymorphisms of the MTRR gene between cases and control subjects.     

Wear Behavior of Multiwalled Carbon Nanotube/AZ31 Composite Obtained by Friction Stir Processing

Multiwalled carbon nanotubes were homogenously dispersed into a magnesium alloy (AZ31) using friction stir processing. The microstructural features, mechanical behaviors including microhardness, and wear properties were investigated. The results showed a significant improvement in wear resistance in the friction stir-processed AZ31 alloy containing multiwalled carbon nanotubes compared to that of the as-received alloy. This was attributed to its higher microhardness and lower coefficient of friction due to the presence of finer matrix grains and uniform dispersion of multiwalled carbon nanotubes.     

Is technological change biased toward energy? A multi-sectoral analysis for the French economy

Since the adoption and implementation of new technologies has an important influence on the structure and performance of the economy in both developed and developing countries, many research papers are devoted to the technology–economy nexus. Motivated by the fact that the impact of technical progress on the demand for different production factors may vary depending on the bias of the technological change, in this paper, by estimating a translog cost-share system and using state-space modeling technique, we investigate to what extent the direction of technical change is biased toward energy and away from other factors. By applying this methodology to the French economy for the period 1978–2006 the obtained results suggest that: first, technical change has a non-neutral impact on factor demands; second, capital-saving technical progress is present in the majority of the sectors studied; third, energy demand has increased in all sectors but electricity and gas. These findings may have important policy implications for environmental and energy issues in France.