EXPERIMENTAL STUDY OF REACTIVITY AND MORPHOLOGICAL CHANGE OF FE-BASED CHEMICAL LOOPING PARTICLE IN CYCLIC REDUCTION-OXIDATION REACTIONS

Coal, an abundant and stable energy source, is playing an important role in current and future global energy supplies. Therefore, there is intensive research currently focusing on coal-conversion in a high-efficiency and environmentally-friendly way. The Chemical Looping Processes (CLPs) developed at The Ohio State University, can achieve H2 and power generation from coal with 100% CO2 capture. It uses Fe-based particles (Fe2O3) as oxygen carrier to capture and release oxygen in a cyclic manner, while coal-derived syngas (CO + H2) can be converted into high-temperature heat for power generation with 100% CO2 capture. It is widely believed that particle sintering is the main reason that cause of morphological deterioration and reactivity decay of pure Fe2O3 solids. Hence, most current efforts are put on anti-sintering and optimization of reaction condition. In this study, the exact solid deactivation mechanism was explored in order to achieve optimal particle development strategies. Reaction time, reaction temperature, and reduction-oxidation reaction cycle were the three factors studied to examine their individual effects on the resulting solid properties. The data showed that longer reaction time, lower reaction temperature, and multiple cyclic reactions would decrease a particle’s surface area, pore volume, and corresponding reactivity. This structural change is a complex process which involves multiple factors in the cyclic reaction, such as the solid’s inherent properties, solid-phase ionic transfer, and reaction condition. This study provides a better understanding of the deactivation mechanism of Fe-based chemical looping particles. It also has a pronounced influence and instructive significance to the future of particle development.College of Engineering, The Ohio State UniversityNo embarg

On Capacity and Delay of Multi-channel Wireless Networks with Infrastructure Support

In this paper, we propose a novel multi-channel network with infrastructure support, called an MC-IS network, which has not been studied in the literature. To the best of our knowledge, we are the first to study such an MC-IS network. Our proposed MC-IS network has a number of advantages over three existing conventional networks, namely a single-channel wireless ad hoc network (called an SC-AH network), a multi-channel wireless ad hoc network (called an MC-AH network) and a single-channel network with infrastructure support (called an SC-IS network). In particular, the network capacity of our proposed MC-IS network is $\sqrt{n \log n}$ times higher than that of an SC-AH network and an MC-AH network and the same as that of an SC-IS network, where $n$ is the number of nodes in the network. The average delay of our MC-IS network is $\sqrt{\log n/n}$ times lower than that of an SC-AH network and an MC-AH network, and $\min\{C_I,m\}$ times lower than the average delay of an SC-IS network, where $C_I$ and $m$ denote the number of channels dedicated for infrastructure communications and the number of interfaces mounted at each infrastructure node, respectively. Our analysis on an MC-IS network equipped with omni-directional antennas only has been extended to an MC-IS network equipped with directional antennas only, which are named as an MC-IS-DA network. We show that an MC-IS-DA network has an even lower delay of $\frac{c}{\lfloor \frac{2\pi}{\theta}\rfloor \cdot C_I}$ compared with an SC-IS network and our MC-IS network. For example, when $C_I=12$ and $\theta=\frac{\pi}{12}$, an MC-IS-DA network can further reduce the delay by 24 times lower that of an MC-IS network and reduce the delay by 288 times lower than that of an SC-IS network.Comment: accepted, IEEE Transactions on Vehicular Technology, 201

Depth Assisted Full Resolution Network for Single Image-based View Synthesis

Researches in novel viewpoint synthesis majorly focus on interpolation from multi-view input images. In this paper, we focus on a more challenging and ill-posed problem that is to synthesize novel viewpoints from one single input image. To achieve this goal, we propose a novel deep learning-based technique. We design a full resolution network that extracts local image features with the same resolution of the input, which contributes to derive high resolution and prevent blurry artifacts in the final synthesized images. We also involve a pre-trained depth estimation network into our system, and thus 3D information is able to be utilized to infer the flow field between the input and the target image. Since the depth network is trained by depth order information between arbitrary pairs of points in the scene, global image features are also involved into our system. Finally, a synthesis layer is used to not only warp the observed pixels to the desired positions but also hallucinate the missing pixels with recorded pixels. Experiments show that our technique performs well on images of various scenes, and outperforms the state-of-the-art techniques

A pilot study of intralesional ranibizumab on pterygium vascularity, size and recurrence rate

Introduction: Pterygium is a common eye disorder in Malaysia due to the country’s location near to the equator. Recent study has found that vascular endothelial growth factor (VEGF) is present in great amount in pterygium epithelium especially in its head compared to normal conjunctiva suggesting that VEGF is involved in the angiogenesis and proliferative fibrovascular growth of pterygium. Thus, anti-VEGF has been proposed as an off-label adjunct to pterygium surgery. Objective: To evaluate the vascularity and size of primary pterygium after intralesional ranibizumab injection and the recurrence rate following sutureless pterygium surgery. Methodology: Patients presenting for primary pterygium excision who fulfilled our inclusion and exclusion criteria were identified. They were then randomised into treatment and control groups. Treatment group was injected with intralesional ranibizumab (0.3 mg/0.03 mL) 1 week prior to surgery. Anterior segment photographs were taken before and 1 week after the injection. Changes in pterygium vascularity (percentage of pterygium area covered by vessels) and size (percentage of cornea area covered by pterygium) were measured using image analysis software, Image J. 1 week after ranibizumab injection, both treatment and control groups underwent pterygium excision and conjunctiva autograft adhesion with fibrin glue. Patients were followed-up for 1 year to monitor for recurrence and complication. Results: 36 patients (18 each group) completed the study. Mean change in pterygium vascularity was 1.48 (4.65)% while pterygium size was 0.28 (2.71) %. Both reductions were not statistically significant (p = 0.195 and 0.672 respectively). Recurrence rate in treatment group was 22.2% (n = 4) while controlled group was 16.7% (n = 3). Recurrence rate between groups was not statistically significant (p > 0.950). Conclusion: Single intralesional injection of ranibizumab (0.3 mg/0.03 mL) did not reduce the pterygium vascularity and size significantly in 1 week time. Pre-operative intralesional ranibizumab did not reduce pterygium recurrence rate

A Comparison study of the implementation of digital camera’s RAW and JPEG and scanner’s TIFF file formats, and color management procedures for inkjet textile printing applications

The objective of this research was to evaluate the results and characteristics of utilizing different image file formats in inkjet textile printing. Two format files derived from digital camera (JPEG and RAW format files) and two TIFF format files derived from scanning the transparency films were sent through color management processes and adjustment procedures. These images files were then rendered on 100% cotton fabric using an inkjet textile printer. The evaluation and analysis of the image files and textile patterns were based on visual assessment and measured values. The end result of this experiment was mainly to evaluate the image resolution, color difference, density and texture reproduction; specifically, outlining the advantages and disadvantages between different file formats for digital textile printing application. The investigation indicated that the JPEG, RAW, and TIFF format files appeared to have discrepancy in the original image file, and also had difference in color accuracy when reproducing on cotton fabric, but showed similar results in printable density range, print contrast, and texture reproduction. Photographing in the RAW file format and then converting to the TIFF file format ensures the image of having robust editing capability and precise print result in color accuracy. If using JPEG file format, users must caution the posterization phenomenon and discontinuous tone problem. For transparency film, either scanning in original size and then applying interpolation twice from the original size or scanning directly in target size results in similar performance. However, to achieve color accuracy, users should consider utilizing digital camera and avoid using film in the workflow. The digital textile printing provides a new and easier approach and lowers the boundary for entering the textile printing industry. This technology makes the product customization and one-of-a-kind short run become possible. However, when entering this field, the new users certainly will encounter the problems immediately related to the different image file formats. This research offers a resolution to answer the question about different file formats

Towards supramolecular heterojunctions : self-assembled hydrogen-bonded architectures for organic photovoltaic devices

Ces travaux ont pour but la conception et la synthèse de composants moléculaires photo-et électro-actifs programmés l’auto-organiser en hétérojonctions supramoléculaires actives en conversion photovoltaïque. L’utilisation de fullerène (C60) et d'oligothiophène portant des motifs de reconnaissances moléculaires par liaisons hydrogène permet la conception d’architectures supramoléculaires en ruban, optimisées pour la séparation et la transport de charges efficaces. L’étude de monocouches auto-assemblées portant des groupes de reconnaissance moléculaires permet de structurer la couche active et augmente la réponse photovoltaïque des dispositifs. La fabrication de cellules solaires organiques à l’état solide avec ces matériaux auto-assemblées a également été étudiée.The aim of this research is to focus on the implementation of supramolecular self-assembly of photo-and electro-active components programmed to self-organize into molecular heterojunctions for efficient light-to-electrical energy conversion. The incorporation of fullerene and oligothiophene appended with complementary hydrogen-bonding molecular recognition motifs allows the design of supramolecular architectures engineered to achieve efficient charge separation and transport. In addition, the incorporation of self-assembled monolayers bearing hydrogen-bonding molecular recognition end-groups on electrode surface further enhances the photovoltaic response of the functional supramolecular devices. The fabrication of solid-state organic solar cells with the self-assembled photoactive materials also has been investigated