Robust Ground Target Detection by SAR and IR Sensor Fusion Using Adaboost-Based Feature Selection

Long-range ground targets are difficult to detect in a noisy cluttered environment using either synthetic aperture radar (SAR) images or infrared (IR) images. SAR-based detectors can provide a high detection rate with a high false alarm rate to background scatter noise. IR-based approaches can detect hot targets but are affected strongly by the weather conditions. This paper proposes a novel target detection method by decision-level SAR and IR fusion using an Adaboost-based machine learning scheme to achieve a high detection rate and low false alarm rate. The proposed method consists of individual detection, registration, and fusion architecture. This paper presents a single framework of a SAR and IR target detection method using modified Boolean map visual theory (modBMVT) and feature-selection based fusion. Previous methods applied different algorithms to detect SAR and IR targets because of the different physical image characteristics. One method that is optimized for IR target detection produces unsuccessful results in SAR target detection. This study examined the image characteristics and proposed a unified SAR and IR target detection method by inserting a median local average filter (MLAF, pre-filter) and an asymmetric morphological closing filter (AMCF, post-filter) into the BMVT. The original BMVT was optimized to detect small infrared targets. The proposed modBMVT can remove the thermal and scatter noise by the MLAF and detect extended targets by attaching the AMCF after the BMVT. Heterogeneous SAR and IR images were registered automatically using the proposed RANdom SAmple Region Consensus (RANSARC)-based homography optimization after a brute-force correspondence search using the detected target centers and regions. The final targets were detected by feature-selection based sensor fusion using Adaboost. The proposed method showed good SAR and IR target detection performance through feature selection-based decision fusion on a synthetic database generated by OKTAL-SE.1146Ysciescopu

Thermal and plasma-enhanced ALD of Ta and Ti oxide thin films from alkylamide precursors

We investigated the thermal and plasma-enhanced atomic layer deposition (PE-ALD) of tantalum and titanium oxides from representative alkylamide precursors, Ta(NMe2)(5) (pentakis(dimethylamino)Ta, PDMAT) and Ti(NMe2)(4) [tetrakis(dimethylamido)Ti, TDMAT]. ALD of Ta2O5 by PDMAT with water or oxygen plasma produced pure Ta2O5 films with good self-saturation growth characteristics. However, incomplete self-saturation was observed for TiO2 ALD from TDMAT. The film properties including microstructure, chemical composition, and electrical properties are discussed focusing on the comparative studies between thermal and PE-ALD processes for both oxides. The results indicate that the PDMAT is a promising precursor for both thermal and PE-ALD of Ta2O5.open117474sciescopu

The effects of nitrogen profile and concentration on negative bias temperature instability of plasma enhanced atomic layer deposition HfOxNy prepared by in situ nitridation

We have prepared plasma enhanced-atomic layer deposition HfOxNy thin films by in situ nitridation using nitrogen/oxygen mixture plasma and studied the effects of nitrogen contents and profiles on the negative bias temperature instability (NBTI). The nitrogen depth profiles and concentrations were controlled by changing the exposure sequences and the nitrogen to oxygen flow ratio, respectively. The best immunity to NBTI degradations was obtained for the nitrogen to oxygen ratio of 2:1 when nitrogen atoms are incorporated away from the high k/Si interface. We propose a dielectric degradation mechanism based on the reaction-diffusion model in which nitrogen plays a role of hydrogen generator at the interface and diffusion barrier in the bulk film. (c) 2008 American Institute of Physics. [DOI: 10.1063/1.2978360]open111012sciescopu

Electrical properties of atomic layer deposition HfO2 and HfOxNy on si substrates with various crystal orientations

The use of high-k gate oxide on Si substrates with alternative orientations is expected to contribute for the fabrication of high mobility devices. In this paper, the interfacial and electrical properties of the plasma enhanced atomic layer deposition (PE-ALD) HfO2 and HfOxNy gate oxides on Si substrates with three different crystal orientations, (001), (011), and (111),were comparatively studied. While PE-ALD HfO2 films were prepared using oxygen plasma as a reactant, PE-ALD HfOxNy films were prepared by in situ nitridation using oxygen/nitrogen mixture plasma. For all crystal orientations, in situ nitridation using oxygen/nitrogen mixture plasma improved electrical properties producing lower leakage currents and smaller equivalent oxide thickness values. Both HfO2 and HfOxNy films have shown the lowest leakage current and interface state density on Si (001), whereas the poorest electrical properties were obtained on Si (111). The results are discussed based on the experimental results obtained from various analytical techniques, including I-V, C-V, conductance methods, and X-ray photoelectron spectroscopy. (C) 2008 The Electrochemical Society.open111818sciescopu

Atomic scale nitrogen depth profile control during plasma enhanced atomic layer deposition of high k dielectrics

Nitrogen incorporation produces several benefits in the performance of high k gate oxides. However, since too much nitrogen incorporation at the interface of gate dielectric can result in device degradation, the atomic scale control of nitrogen depth profile is desirable. In this study, the authors have improved electrical properties and interface properties by depth profile control of in situ nitrogen incorporation during plasma enhanced atomic layer deposition. The best electrical properties in terms of hysteresis, equivalent oxide thickness, and interface states were obtained when the nitrogen is incorporated in the middle of the thin film, which has not been achievable by other techniques.open111719sciescopu

Age differences in social comparison tendency and personal relative deprivation

We examined age-related differences in social comparison orientation and personal relative deprivation (PRD). In Study 1, participants (N = 1,290) reported their tendencies to engage in social comparisons and PRD. Older adults reported lower levels of social comparison tendency and PRD, and social comparison tendency mediated the relation between age and PRD. The findings reported in Study 1 were replicated in Study 2 using a sample of participants between the ages of 18 to 30 (n = 180) and 60+ years old (n = 176). Our findings provide evidence that older adults report lower levels of social comparison tendency that, in turn, relate to lower levels of PRD.This research was funded by a grant from the Leverhulme Trust (RPG-2013-148).This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.paid.2015.08.00

Structural Characterization of Anticancer Drug Paclitaxel and Its Metabolites Using Ion Mobility Mass Spectrometry and Tandem Mass Spectrometry

Paclitaxel (PTX) is a popular anticancer drug used in the treatment of various types of cancers. PTX is metabolized in the human liver by cytochrome P450 to two structural isomers, 3'-p-hydroxypaclitaxel (3p-OHP) and 6 alpha-hydroxypaclitaxel (6 alpha-OHP). Analyzing PTX and its two metabolites, 3p-OHP and 6 alpha-OHP, is crucial for understanding general pharmacokinetics, drug activity, and drug resistance. In this study, electrospray ionization ion mobility mass spectrometry (ESI-IM-MS) and collision induced dissociation (CID) are utilized for the identification and characterization of PTX and its metabolites. Ion mobility distributions of 3p-OHP and 6 alpha-OHP indicate that hydroxylation of PTX at different sites yields distinct gas phase structures. Addition of monovalent alkali metal and silver metal cations enhances the distinct dissociation patterns of these structural isomers. The differences observed in the CID patterns of metalated PTX and its two metabolites are investigated further by evaluating their gas-phase structures. Density functional theory calculations suggest that the observed structural changes and dissociation pathways are the result of the interactions between the metal cation and the hydroxyl substituents in PTX metabolites.1155Ysciescopu

Polymeric biomaterials for the delivery of platinum-based anticancer drugs

Since cisplatin, cis-diamminedichloroplatinum(II), received FDA approval for use in cancer treatment in 1978, platinum-based drugs have been one of the most widely used drugs for the treatment of tumors in testicles, ovaries, head and neck. However, there are concerns associated with the use of platinum-based anticancer drugs, owing to severe side effects and drug resistance. In order to overcome these limitations, various drug-delivery systems have been developed based on diverse organic and inorganic materials. In particular, the versatility of polymeric materials facilitates the tuning of drug-delivery systems to meet their primary goals. This review focuses on the progress made over the last five years in the application of polymeric nanoparticles for the delivery of platinum-based anticancer drugs. The present article not only describes the fundamental principles underlying the implementation of polymeric nanomaterials in platinum-based drug delivery, but also summarizes concepts and strategies employed in the development of drug-delivery systems.open112519Ysciescopu

Atomic layer deposition of Ta-based thin films: Reactions of alkylamide precursor with various reactants

The growth mechanisms and film properties of atomic layer deposition (ALD) Ta-based thin films were investigated from alkylamide precursor [Ta(NMe2)(5), (PDMAT)]. The reactions of PDMAT with various reactants including water, NH3, Oxygen, and hydrogen plasma were studied and the resulting film properties were investigated by various analysis techniques. For TaN ALD from NH3 and H plasma, the films were contaminated by considerable amount of carbon, while the Ta2O5 deposited from water and O plasma were quite pure. Also, nitrogen was incorporated for ALD from PDMAT and H plasma, while no nitrogen incorporation was observed for O-plasma based plasma enhanced-ALD of Ta2O5 except at high deposition temperature over 300 degrees C. The results were comparatively discussed focusing on the differences in growth mechanism depending on reactants. (c) 2006 American Vacuum Society.open113639sciescopu

Migration of atmospheric convection coupled with ocean currents pushes El Nino to extremes

The warm phase of El Nino-Southern Oscillation can grow much stronger than the cold phase, but the associated dynamics are not well understood. Here we show that the anomalous zonal advection of warm water is the major process that pushes El Nino to extremes and that this anomalous advection results from the coupling of oceanic currents with eastward migration of the atmospheric convection; a greater zonal advection is associated with a greater extent of the eastward migration. By contrast, there is a limited extent for westward migration during La Nina. Climate models that successfully simulate the amplitude asymmetry display a systematic linkage of a greater longitudinal movement of the convection center with a stronger zonal advection and greater El Nino amplitude. In a warming world, the longitudinal migration of convection response increases, as does the role of zonal advection, increasing the frequency of future extremes of El Nino.△1132Ysciescopu