A Framework for Moving Least Squares Method with Total Variation Minimizing Regularization

In this paper, we propose a computational framework to incorporate regularization terms used in regularity based variational methods into least squares based methods. In the regularity based variational approach, the image is a result of the competition between the fidelity term and a regularity term, while in the least squares based approach the image is computed as a minimizer to a constrained least squares problem. The total variation minimizing denoising scheme is an exemplary scheme of the former approach with the total variation term as the regularity term, while the moving least squares method is an exemplary scheme of the latter approach. Both approaches have appeared in the literature of image processing independently. By putting schemes from both approaches into a single framework, the resulting scheme benefits from the advantageous properties of both parties. As an example, in this paper, we propose a new denoising scheme, where the total variation minimizing term is adopted by the moving least squares method. The proposed scheme is based on splitting methods, since they make it possible to express the minimization problem as a linear system. In this paper, we employed the split Bregman scheme for its simplicity. The resulting denoising scheme overcomes the drawbacks of both schemes, i.e., the staircase artifact in the total variation minimizing based denoising and the noisy artifact in the moving least squares based denoising method. The proposed computational framework can be utilized to put various combinations of both approaches with different properties together.     

Microstructural Evidence for Diffusion-Driven Tetragonal-to-Orthorhombic Phase Transformation in Y-Ba-Cu-O Superconductor

Microstructures of Y-Ba-Cu-O superconductor were observed using a polarized microscope. Orthorhombic and tetragonal phases were easily distinguished by the optical etching with cross-polarized light. In the specimen cooled rapidly in oxygen, it was possible to see the path of oxygen diffusion by observing the variation of the twin concentration. At the boundary between transformed and untransformed materials, evidence for diffusion-driven transformation could be clearly seen.     

Synthesis of biodegradable PU/PEGDA IPNs having micro-separated morphology for enhanced blood compatibility

Summary New biodegradable hydrophobic polyurethane (PU)/hydrophilic poly (ethylene glycol) diacrylate (PEGDA) IPN was simultaneously synthesized with changing the molecular weight of PEGDA to investigate the effect of crosslinking density on the degree of phase separation. PU was modified using biodegradable poly(-caprolactone)diol and the hydroxy group of PEG was substituted to crosslinkable acrylate group having double bond, which induce photo-polymerization. The sturucture of PEGDA was confirmed by NMR. Because the reaction rate of PEGDA was faster than that of PU, the continuous matrix of the micro-separated PU/PEGDA IPNs having amphiphilic character was made of hydrophilic PEGDA-rich phase. All IPNs have sea-island morphology resulting from the suppressed phase separation. The effect of the degree of phase separation on blood compatibility was investigated.     

Temperature effect on the permeation through poly(2-hydroxyethyl methacrylate) membrane

The temperature dependence of permeability through highly syndiotactic poly(2-hydroxyethyl methacrylate) [P(HEMA)] membrane is reported for highly polar organic solutes such as ureas, methyl substituted ureas and amides, and for NaCl and Na₂SO₄. The membranes used were equilibrated in distilled water at each temperature before measurements. From the linear correlationship between the excess heat capacities, ?C_p^o(excess) in aqueous solution at infinite dilution and the permeability parameter PM^1/3, it is found that the water structure perturbing capability of the polar organic solutes is a controlling factor in the permeation mechanism at relatively low temperature, where P(HEMA) membrane has higher water content and more structured water. In addition, it is found that the poor separation for urea of cellulose acetate membrane in the reverse osmosis practice is due to the higher water structure-breaking capability of urea.     

Corrosion resistance of austenitic stainless steel separator for molten carbonate fuel cell

STS310S and SC-STS310S (simultaneously co-deposited chromium and aluminum onto 310S austenitic stainless steel substrate by pack-cementation process) were used as separator materials on the cathode side of a molten carbonate fuel cell. With the STS310S, corrosion proceeded via three steps; a formation step of unstable corrosion product, a protection step against corrosion until breakaway, and an advance step of corrosion after breakaway. The final corrosion product was LiFeO₂ and the loss of mass was 6.5 mg/cm² after a corrosion test of 480 hr at 650°C. The SC-STS310S showed more effective corrosion resistance, however, than did common STS310S. There was especially no corrosion loss on the SC-STS310S after the 480 hr corrosion test. It is anticipated that it will be very useful as an alternative separator on the cathode side off the MCFC in the future.     

Video-based weathering gallery

We present a simple and effective method for constructing a gallery that consists of weathering effect elements called time-dependent appearance manifolds (TDAMs). Since TDAMs are computed from sample video clips showing dynamic weathering phenomena, they represent very smooth changes in the appearance of weathered pixels over time. Once a gallery with a variety of weathering effects is prepared, users can interactively choose and apply the predefined effects onto the surface of 3D graphic models and then finally assign the most appropriate one. This video-based weathering method can be implemented with very simple algorithms and it supports predictable, intuitive, and natural effects. Our system allows users to produce photorealistic augmented videos that include 3D graphic models weathered by our method. Moreover, users can easily enhance the realism of the augmented videos by manipulating rendering parameters such as the degree of weathering, texturing, lighting, and shadowing through user-friendly graphical user interfaces (GUIs).     

An online fault tolerant actor-critic neuro-control for a class of nonlinear systems using neural network HJB approach

In this paper, we propose an actor-critic neuro-control for a class of continuous-time nonlinear systems under nonlinear abrupt faults, which is combined with an adaptive fault diagnosis observer (AFDO). Together with its estimation laws, an AFDO scheme, which estimates the faults in real time, is designed based on Lyapunov analysis. Then, based on the designed AFDO, a fault tolerant actor- critic control scheme is proposed where the critic neural network (NN) is used to approximate the value function and the actor NN updates the fault tolerant policy based on the approximated value function in the critic NN. The weight update laws for critic NN and actor NN are designed using the gradient descent method. By Lyapunov analysis, we prove the uniform ultimately boundedness (UUB) of all the states, their estimation errors, and NN weights of the fault tolerant system under the unpredictable faults. Finally, we verify the effectiveness of the proposed method through numerical simulations.     

Perceived Visual Complexity and Visual Search Performance of Automotive Instrument Cluster: A Quantitative Measurement Study

Advancements in technology have spurred the development of new in-vehicle applications. Drivers are faced with different driving contexts due to an increase in the number of devices that provide a wealth of diverse information. However, such a scenario can cause drivers to become distracted. Therefore, research on how the presentation of visual information can affect drivers’ performance is important. In this study, an analysis of quantifiable measurements that affect drivers’ perception of visual complexity and visual search performance was conducted. A questionnaire was administered to assess subjective perception of visual complexity, and a user experiment using eye tracking was designed to explore participants’ visual search performance. The results of subjective visual complexity perception and visual search performance suggested that some objective measurement variables were significantly related only to perceived visual complexity, whereas others affected both subjective and behavioral measurements. Thus it is possible to predict which quantifiable measurement variables affect subjective perception of visual complexity and which affect visual search performance. Therefore, this study allows understanding and explaining of perception of visual complexity by quantifiable measurements and the different ways by which these measurements affect visual search performance.     

Understanding Usability and User Experience of Web-Based 3D Graphics Technology

As Web-based interactive 3D graphics (Web 3D), popularly referred to as Virtual Reality, continue to become more affordable, research and development groups in various fields have been adopting Web 3D technology. In addition to simulation of 3D content, the ability to instantly display alternative looks has been recognized as an innovative way to improve communication in such fields as product design, architecture, and e-commerce. Despite substantial adoption of Web 3D, how and how much the technology benefits target users as well as the providers who choose to adapt the Web 3D technology are not well understood. Previous research has established that interactive 3D graphics provide users with unique human–computer interaction (HCI). However, little is known about how users experience the Web 3D graphics technology and how user–system interaction contributes to system usability. The purpose of this study is to build new knowledge of the user experience with interactive-3D graphics systems used for product demonstration. By testing the impact of the technology on the user–system interaction and usability and comparing this impact with that of conventional two-dimensional (2D) graphics, this study tries to better understand the Web 3D technology from an interdisciplinary view of technology acceptance, sense of presence, and HCI. The study investigated how system usability is affected by HCI in the context of a furniture-style preference survey. The results of the study display the clear advantage for Web 3D for usability and show that perceived usefulness and sense of presence both mediate the effect of the technology treatment on the usability outcomes. The contribution of this study is that it includes empirical data to show how Web 3D benefits users when adopted in the context of a product demonstration and how the advantage is obtained through the user's interaction with the Web 3D technology.