Co doping induced structural and optical properties of sol-gel prepared ZnO thin films

Cataloged from PDF version of article.The preparation conditions for Co doping process into the ZnO structure were studied by the ultrasonic spray pyrolysis technique. Structural and optical properties of the Co:ZnO thin films as a function of Co concentrations were examined. It was observed that hexagonal wurtzite structure of ZnO is dominant up to the critical value, and after the value, the cubic structural phase of the cobalt oxide appears in the X-ray diffraction patterns. Every band-edge of Co:ZnO films shifts to the lower energies and all are confirmed with the PL measurements. Co substitution in ZnO lattice has been proved by the optical transmittance measurement which is observed as the loss of transmission appearing in specific region due to Co2+ characteristic transitions. © 2014 Elsevier B.V. All rights reserved

iMAPPER: Interaction-guided Scene Mapping from Monocular Videos

Next generation smart and augmented reality systems demand a computational understanding of monocular footage that captures humans in physical spaces to reveal plausible object arrangements and human-object interactions. Despite recent advances, both in scene layout and human motion analysis, the above setting remains challenging to analyze due to regular occlusions that occur between objects and human motions. We observe that the interaction between object arrangements and human actions is often strongly correlated, and hence can be used to help recover from these occlusions. We present iMapper, a data-driven method to identify such human-object interactions and utilize them to infer layouts of occluded objects. Starting from a monocular video with detected 2D human joint positions that are potentially noisy and occluded, we first introduce the notion of interaction-saliency as space-time snapshots where informative human-object interactions happen. Then, we propose a global optimization to retrieve and fit interactions from a database to the detected salient interactions in order to best explain the input video. We extensively evaluate the approach, both quantitatively against manually annotated ground truth and through a user study, and demonstrate that iMapper produces plausible scene layouts for scenes with medium to heavy occlusion. Code and data are available on the project page

{CurveFusion}: {R}econstructing Thin Structures from {RGBD} Sequences

We introduce CurveFusion, the first approach for high quality scanning of thin structures at interactive rates using a handheld RGBD camera. Thin filament-like structures are mathematically just 1D curves embedded in R^3, and integration-based reconstruction works best when depth sequences (from the thin structure parts) are fused using the object's (unknown) curve skeleton. Thus, using the complementary but noisy color and depth channels, CurveFusion first automatically identifies point samples on potential thin structures and groups them into bundles, each being a group of a fixed number of aligned consecutive frames. Then, the algorithm extracts per-bundle skeleton curves using L1 axes, and aligns and iteratively merges the L1 segments from all the bundles to form the final complete curve skeleton. Thus, unlike previous methods, reconstruction happens via integration along a data-dependent fusion primitive, i.e., the extracted curve skeleton. We extensively evaluate CurveFusion on a range of challenging examples, different scanner and calibration settings, and present high fidelity thin structure reconstructions previously just not possible from raw RGBD sequences

Amyloid Inspired Self-Assembled Peptide Nanofibers

Cataloged from PDF version of article.Amyloid peptides are important components in many degenerative diseases as well as in maintaining cellular metabolism. Their unique stable structure provides new insights in developing new materials. Designing bioinspired selfassembling peptides is essential to generate new forms of hierarchical nanostructures. Here we present oppositely charged amyloid inspired peptides (AIPs), which rapidly self-assemble into nanofibers at pH 7 upon mixing in water caused by noncovalent interactions. Mechanical properties of the gels formed by selfassembled AIP nanofibers were analyzed with oscillatory rheology. AIP gels exhibited strong mechanical characteristics superior to gels formed by self-assembly of previously reported synthetic short peptides. Rheological studies of gels composed of oppositely charged mixed AIP molecules (AIP-1 + 2) revealed superior mechanical stability compared to individual peptide networks (AIP-1 and AIP-2) formed by neutralization of net charges through pH change. Adhesion and elasticity properties of AIP mixed nanofibers and charge neutralized AIP-1, AIP-2 nanofibers were analyzed by high resolution force− distance mapping using atomic force microscopy (AFM). Nanomechanical characterization of self-assembled AIP-1 + 2, AIP-1, and AIP-2 nanofibers also confirmed macroscopic rheology results, and mechanical stability of AIP mixed nanofibers was higher compared to individual AIP-1 and AIP-2 nanofibers self-assembled at acidic and basic pH, respectively. Experimental results were supported with molecular dynamics simulations by considering potential noncovalent interactions between the amino acid residues and possible aggregate forms. In addition, HUVEC cells were cultured on AIP mixed nanofibers at pH 7 and biocompatibility and collagen mimetic scaffold properties of the nanofibrous system were observed. Encapsulation of a zwitterionic dye (rhodamine B) within AIP nanofiber network was accomplished at physiological conditions to demonstrate that this network can be utilized for inclusion of soluble factors as a scaffold for cell culture studies. Copyright © 2012 American Chemical Societ

Feasibility Investigation of Upgrading Gravel Road to Otta Seal Surface: an Economic Analysis Approach

The Norwegian Road Authorities desired that a surface treatment be cost-effective to provide a faster return on investment, perform (as perceived by the road user) in a manner similar to conventional bituminous surfacing, and comply with the following requirements: • Be cheap and easy to implement • Utilize locally-available aggregates • Be impervious to prevent water incursion into moisture-susceptible base material • Be very flexible, durable, and easy to maintain. Such a bituminous surface treatment, referred to as in 1963, and initial field trials were carried out during 1963-1965 in the Otta Valley, Norway. Although Nordic countries, Asia, Africa, New Zealand, and South America have continued to see increasing use of Otta seal (1), its use in the US is currently rather limited due to a lack of knowledge and of the empirical design approach associated with this technique that requires evaluation of trial or demonstration sections before deployment. Minnesota, South Dakota, and Iowa are the only states that have currently completed Otta seal projects in the US, and a summary discussion of MN’s and SD’s experiences with Otta seal is given in this section (2, 3). In this paper, the life cycle cost of surfacing and maintaining an upgraded gravel road to an Otta seal coated surface over a one-mile generic road in Minnesota was evaluated through deterministic and stochastic life-cycle cost analysis (LCCA). Since various road and highway agencies in Minnesota have implemented Otta seal and provided access to the historical cost records needed to complete this study, Minnesota was chosen for a case study for conducting the analysis