Enhancing electrochromic properties of polypyrrole by silsesquioxane nanocages

A new monomer, octa(thiophenephenyl)silsesquioxane (OThiophenePS) was synthesized via click chemistry. The chemical structure of OThiophenePS was characterized by nuclear magnetic resonance (¹H NMR) and Fourier transform infrared (FT-IR) spectroscopies. Electrochemical polymerization of pyrrole with OThiophenePS was performed resulting in polypyrrole-attached, polyhedral oligomeric silsesquioxane (OPS–PPy). The spectroelectrochemical studies show that the electrochromic properties of (OPS–PPy) are superior to those of polypyrrole (PPy). This great improvement can be attributed to the more accessible doping sites and the facile ion movement during the redox switching brought by the loose packing of the PPy chains.     

Semi-Supervised Deep Learning for Multi-Tissue Segmentation from Multi-Contrast MRI

Journal of Signal Processing Systems - Segmentation of thigh tissues (muscle, fat, inter-muscular adipose tissue (IMAT), bone, and bone marrow) from magnetic resonance imaging (MRI) scans is useful...     

Using fuzzy inference system for architectural space analysis

Though architectural space is the main source and the only indispensable component of any architectural construction, in many cases its boundaries are uncertain, leading intuitive spatial design. Creating a mathematical model of architectural space with concrete results will offer many possibilities for design process in analysing spatial organization, independently from in architect's experience and intuitions. This paper presents a fuzzy inference system based spatial analysis model for spatial analysis for architectural design which brings many advantages to design process. The aim of this article is to investigate the potential of a fuzzy system with a Mamdami inference engine, considering different numbers of membership functions. Two venues have been selected and the fuzzy inference system based spatial analysis model is applied. For better judgement, outcomes of the model have been compared to depthmap analysis model. The results of the model indicate that fuzzy inference system based spatial analysis model performs very well, even with the limited and imprecise data. Such prototype can evolve into a tool for identifying spatial formations for improvements during the architectural design process.     

Simultaneously learning actions and goals from demonstration

Our research aim is to develop interactions and algorithms for learning from naïve human teachers through demonstration. We introduce a novel approach to leverage the goal-oriented nature of human teachers by learning an action model and a goal model simultaneously from the same set of demonstrations. We use robot motion data to learn an action model for executing the skill. We use a generic set of perceptual features to learn a goal model and use it to monitor the executed action model. We evaluate our approach with data from 8 naïve teachers demonstrating two skills to the robot. We show that the goal models in the perceptual feature space are consistent across users and correctly recognize demonstrations in cross-validation tests. We additionally observe that a subset of users were not able to teach a successful action model whereas all of them were able to teach a mostly successful goal model. When the learned action models are executed on the robot, the success was on average 66.25 %. Whereas the goal models were on average 90 % correct at deciding on success/failure of the executed action, which we call monitoring.     

A gantry-based tri-modality system for bioluminescence tomography

A gantry-based tri-modality system that combines bioluminescence (BLT), diffuse optical (DOT), and x-ray computed tomography (XCT) into the same setting is presented here. The purpose of this system is to perform bioluminescence tomography using a multi-modality imaging approach. As parts of this hybrid system, XCT and DOT provide anatomical information and background optical property maps. This structural and functional a priori information is used to guide and restrain bioluminescence reconstruction algorithm and ultimately improve the BLT results. The performance of the combined system is evaluated using multi-modality phantoms. In particular, a cylindrical heterogeneous multi-modality phantom that contains regions with higher optical absorption and x-ray attenuation is constructed. We showed that a 1.5 mm diameter bioluminescence inclusion can be localized accurately with the functional a priori information while its source strength can be recovered more accurately using both structural and the functional a priori information.     

TESLA: an extended study of an energy-saving agent that leverages schedule flexibility

This paper presents transformative energy-saving schedule-leveraging agent (TESLA), an agent for optimizing energy usage in commercial buildings. TESLA’s key insight is that adding flexibility to event/meeting schedules can lead to significant energy savings. This paper provides four key contributions: (i) online scheduling algorithms, which are at the heart of TESLA, to solve a stochastic mixed integer linear program for energy-efficient scheduling of incrementally/dynamically arriving meetings and events; (ii) an algorithm to effectively identify key meetings that lead to significant energy savings by adjusting their flexibility; (iii) an extensive analysis on energy savings achieved by TESLA; and (iv) surveys of real users which indicate that TESLA’s assumptions of user flexibility hold in practice. TESLA was evaluated on data gathered from over 110,000 meetings held at nine campus buildings during an 8-month period in 2011–2012 at the University of Southern California and Singapore Management University. These results and analysis show that, compared to the current systems, TESLA can substantially reduce overall energy consumption.     

Template‐Based Synthesis of Aluminum Nitride Hollow Nanofibers Via Plasma‐Enhanced Atomic Layer Deposition

Aluminum nitride (AlN) hollow nanofibers were synthesized via plasma‐enhanced atomic layer deposition using sacrificial electrospun polymeric nanofiber templates having different average fiber diameters (~70, ~330, and ~740 nm). Depositions were carried out at 200°C using trimethylaluminum and ammonia precursors. AlN‐coated nanofibers were calcined subsequently at 500°C for 2 h to remove the sacrificial polymeric nanofiber template. SEM studies have shown that there is a critical wall thickness value depending on the template's average fiber diameter for AlN hollow nanofibers to preserve their shapes after the template has been removed by calcination. Best morphologies were observed for AlN hollow nanofibers prepared by depositing 800 cycles (corresponding to ~69 nm) on nanofiber templates having ~330 nm average fiber diameter. TEM images indicated uniform wall thicknesses of ~65 nm along the fiber axes for samples prepared using templates having ~70 and ~330 nm average fiber diameters. Synthesized AlN hollow nanofibers were polycrystalline with a hexagonal crystal structure as determined by high‐resolution TEM and selected area electron diffraction. Chemical compositions of coated and calcined samples were studied using X‐ray photoelectron spectroscopy (XPS). High‐resolution XPS spectra confirmed the presence of AlN.     

Improvements in microstructural,mechanical, and biocompatibility properties of nano-sized hydroxyapatites doped with yttrium and fluoride

Hydroxyapatite was doped with Y³⁺ (2.5, 5 and 7.5 mol%) and F⁻ (2.5 mol%) ions (2.5YFHA, 5YFHA, 7.5YFHA, respectively) to compare its structural and mechanical properties and cellular response with pure-hydroxyapatite. No second phases were observed by X-ray diffraction spectra of 2.5YFHA. Doped hydroxyapatites had F⁻ bonds in addition to OH⁻ bonds. Hydroxyapatites sintered at 900 and 1100 °C were in nano-size. 7.5YFHA sintered at 1300 °C had the highest microhardness value. 2.5YFHA sintered at 1100 °C had the highest fracture toughness value. MTT viability assays showed high cell attachments on 2.5YFHA. Cell proliferation on 2.5YFHA and 5YFHA sintered at 1100 and 1300 °C was comparable with the control after 5-day culture. The highest ALP production and calcium deposition were observed on all hydroxyapatites sintered at 1100 °C. 2.5YFHA sintered at 1100 °C can be an alternative for hydroxyapatite in orthopedic applications.     

Synthesis and photopolymerization of novel,highly reactive phosphonated-urea-methacrylates for dental materials

An urea methacrylate (1) and two phosphonated methacrylates (2–3) were synthesized from 2-isocyanatoethyl methacrylate (IEM) and benzyl amine (1), diethyl aminomethylphosphonate (2) and diethyl amino(phenyl)methylphosphonate (3). Their photopolymerization rates are notably higher than commercial monomers, despite the presence of only one double bond. Their polymerization rates follow the order 1 ～ 2 > 3 ～ triethylene glycol dimethacrylate (TEGDMA) > 2-hydroxyethyl methacrylate (HEMA). A tendency toward high crosslinking density during thermal bulk polymerizations, low oxygen sensitivity and high conversions with benzophenone during photopolymerization indicated the importance of hydrogen abstraction/chain transfer reactions. It was found that the addition of the monomers to HEMA significantly increased its polymerization rate, proving their utility as replacements for TEGDMA as reactive diluents for 2,2-bis[4-(2-hydroxy-3-methacryloyloxy propyloxy) phenyl] propane (Bis-GMA). Copolymer systems containing 2 and 3 showed improved T_g values compared to Bis-GMA/TEGDMA systems.