Carbodiimide catalysis in cross-linking of cotton cellulose with 1,2,3,4-butanetetracarboxylic acid

This study examined carbodiimde catalysis (cyanamide, dicyandiamide, disodium cyanamide) in the cross-linking of cotton cellulose with 1,2,3,4-butanetetracarboxylic acid (BTCA). Considerable improvement in the smooth drying appearance of the treated cotton substantiated the fact that cellulose cross-linking has been achieved by BTCA in the presence of carbodiimide. Bath pH was a very important factor in determining the performance properties of the treated cotton. Two possible reaction mechanisms were proposed: direct esterification and anhydride intermediate formation. Both pathways involved the formation of urea. Semiquantitative analyses of the spectra obtained by Fourier transform infrared spectroscopy revealed that the cyanamide was somewhat less effective than were dicyandiamide and sodium hypophosphite in esterification efficiency. © 1995 John Wiley & Sons, Inc.     

Ubiquitous-City Integrated Authentication System (UCIAS)

Recently the information and network technologies have been applied to the urban environment. We call this type of a city a ubiquitous-city, or shortly a U-City. Security is an important factor to the success of U-City, by protecting citizen’s private date and by preventing malicious attack to the urban facilities. This paper proposes a U-City Integrated Authentication System (UCIAS), which is a unified authentication model installed in a U-City using the ubiquitous role-based access control protocol—the modified version of the original RBAC protocol. The strong point of UCIAS is fast response time, enhanced scalability and reduced workload, which come from the fact that UCIAS rapidly re-authenticates user inter-domain movements without generating a whole dataset again. We built a simple analytic tool to evaluate UCIAS and the results support our assertion.     

Image-pair-based deblurring with spatially varying norms and noisy image updating

This paper presents a deblurring method that effectively restores fine textures and details, such as a tree’s leaves or regular patterns, and suppresses noises in flat regions using consecutively captured blurry and noisy images. To accomplish this, we used a method that combines noisy image updating with one iteration and fast deconvolution with spatially varying norms in a modified alternating minimization scheme. The captured noisy image is first denoised with a nonlocal means (NL-means) denoising method, and then fused with a deconvolved version of the captured blurred image on the frequency domain, to provide an initially restored image with less noise. Through a feedback loop, the captured noisy image is directly substituted with the initially restored image for one more NL-means denoising, which results in an upgraded noisy image with clearer outlines and less noise. Next, an alpha map that stores spatially varying norm values, which indicate local gradient priors in a maximum-a-posterior (MAP) estimation, is created based on texture likelihoods found by applying a texture detector to the initially restored image. The alpha map is used in a modified alternating minimization scheme with the pair of upgraded noisy images and a corresponding point spread function (PSF) to improve texture representation and suppress noises and ringing artifacts. Our results show that the proposed method effectively restores details and textures and alleviates noises in flat regions.     

A rapid reverse engineering system for reproducing 3D human busts

The most critical problems in the current reverse engineering (RE) are often related to data registration and hole filling. This is because no single scan image is sufficient to describe the entire object since most objects occlude themselves, and some scanned data is likely to be missing on the object. In this paper, we establish a registration and a hole-filling algorithm to solve this problem. The registration module is based upon the standard Iterative Closest Point (ICP) algorithm with some additional heuristics, which help to overcome the limitation of ICP requiring that one of the data scans must be a subset of the other. The aligned triangle mesh is still unsuitable for model reproduction since it often has missing data. The proposed hole filling algorithm reconstructs these missing data with the iterative manner and these data are then smoothed with their neighboring polygonal meshes.We have developed a dedicated system for reproducing a human head and shoulder by using the implemented polygon-based algorithms. The system quickly reconstructs the surface datails of human busts and produces the replica of 3D human model using 4-axis CNC milling machine. Some typical examples are presented to validate the system and further research work is also discussed.     

Reduced order model of three-dimensional Euler equations using proper orthogonal decomposition basis

This study seeks to validate the accuracy and the efficiency of the aerodynamic reduced order model (ROM). In doing this, snapshot data are generated from the full system analysis of a fighter wing problem. From an eigensystem analysis of these snapshots, the basis vector reproducing the behavior of the full system is obtained. The span length, sweep angle, dihedral angle, and spar and rib thickness representing the wing configuration are determined as the input variables. The constructed ROM is applied to the fighter wing problem while varying the input conditions for validation. Subsequently, a comparison of the reduced system with the full system confirmed that the aerodynamic performance is within 4% error and that the L₂ norms are 10⁻⁶ order of the entire flow field. Therefore, the ROM is able to capture the variation of the aerodynamic performance with respect to the input variables. Though there are structural input variables which influence the aerodynamic performance indirectly, the ROM can reproduce the flow field of the full system. Additionally, even if the ROM incurs a high computational cost to generate snapshots, it can represent the behavior of the full system efficiently once the reduced order model is constructed.     

Design and implementation of an augmented reality system using gaze interaction

In this paper, we discuss an interactive optical see-through head-mounted device (HMD) which makes use of a user’s gaze for an augmented reality (AR) interface. In particular, we propose a method to employ a user’s half-blink information for more efficient interaction. Since the interaction is achieved using a user’s gaze and half-blinks, the proposed system can create a more efficient computing environment. In addition, the proposed system can be quite helpful to those who have difficulties in using their hands for conventional interaction methods. The experimental results present the robustness and efficiency of the proposed system.     

Analysis of multiphase space vector pulse-width modulation based on multiple d-q spaces concept

Multiphase motors are usually designed to have the concentrated winding and nonsinusoidal airgap flux density distribution in order to maximize the torque per ampere. This means that the phase voltage of a multiphase motor has the nonsinusoidal waveform. Accordingly, the conventional analysis on a multiphase space vector pulse-width modulation (SVPWM), which is confined to a sinusoidal phase voltage, should be extended to a nonsinusoidal phase voltage. In this paper, based on a multiple d-q spaces concept a novel analysis on a multiphase SVPWM to synthesize an arbitrary nonsinusoidal phase voltage is proposed. Throughout this paper, a five-phase inverter is used as a practical example. The basic concepts can be easily extended to an n-phase inverter.     

Specific interaction of mannosylated glycopolymers with macrophage cells mediated by mannose receptor

Poly[N-p-vinylbenzyl-O-beta-mannopyranosyl-(1-4)-D-gluconamide] (PV-Man) is a polystyrene derivative that contains mannose moieties and interacts with the mannose-receptor-carrying macrophage cell line. To clarify the specific interaction between the PV-Man and the macrophage cell line J774A1, PV-Man polymer labeled with fluorescent fluorescein isothiocyanate (FITC) was used to amonitor the specific interaction, which was visualized by confocal laser microscopy. We found that PV-Man strongly binds to macrophage cells, probably due to a specific interaction mediated by the presence of mannose receptors on the cell membrane. The fluorescence intensity of PV-Man and macrophage cells was up to 7-fold that of any other glycopolymers bound to macrophage cells. Moreover, cellular fluorescence intensity increased significantly with increasing incubation time and polymer concentration. Many macrophage cells strongly express mannose and mannose receptor-related receptors, and receptor-mediated gene transfer via the mannose receptor using a PV-Man glycopolymer is a versatile means of targeted gene delivery into these cells.     

An Integrated Power-Efficient Active Rectifier With Offset-Controlled High Speed Comparators for Inductively Powered Applications

We present an active full-wave rectifier with offset-controlled high speed comparators in standard CMOS that provides high power conversion efficiency (PCE) in high frequency (HF) range for inductively powered devices. This rectifier provides much lower dropout voltage and far better PCE compared to the passive on-chip or off-chip rectifiers. The built-in offset-control functions in the comparators compensate for both turn-on and turn-off delays in the main rectifying switches, thus maximizing the forward current delivered to the load and minimizing the back current to improve the PCE. We have fabricated this active rectifier in a 0.5-μm 3M2P standard CMOS process, occupying 0.18 mm(2) of chip area. With 3.8 V peak ac input at 13.56 MHz, the rectifier provides 3.12 V dc output to a 500 Ω load, resulting in the PCE of 80.2%, which is the highest measured at this frequency. In addition, overvoltage protection (OVP) as safety measure and built-in back telemetry capabilities have been incorporated in our design using detuning and load shift keying (LSK) techniques, respectively, and tested.