Three-dimensional Inkjet Printed Solid Oxide Electrochemical Reactors. I. Yttria-stabilized zirconia Electrolyte

Solid oxide fuel cell (SOFC) and electrolyser (SOE) performances can be enhanced significantly by increasing the densities of (electrode | electrolyte | pore) triple phase boundaries and improving geometric reproducibility and control over composite electrode | electrolyte microstructures, thereby also aiding predictive performance modelling. We developed stable aqueous colloidal dispersions of yttria-stabilized zirconia (YSZ), a common SOFC electrolyte material, and used them to fabricate 2D planar and highly-customisable 3D microstructures by inkjet printing. The effects of solids fraction, particle size, and binder concentration on structures were investigated, and crack-free, non-porous electrolyte planes were obtained by tailoring particle size and minimising binder concentration. Micro-pillar arrays and square lattices were printed with the optimised ink composition, and a minimum feature size of 35 μm was achieved in sintered structures, the smallest published to-date. YSZ particles were printed and sintered to a 23 μm thick planar electrolyte in a Ni-YSZ|YSZ|YSZ-LSM|LSM electrolyser for CO2 splitting; a feed of 9:1 CO2:CO mixture at 1.5 V and 809 °C produced a current density of −0.78 A cm−2 even without more complex 3D electrode | electrolyte geometries

Energy management system and pervasive service-oriented networks

In this work, we study the energy management system (EMS) in the customer domain of the Smart Grid. We discuss the desired features and design issues, highlight the characteristics and identify the challenges. To address the challenges, we propose the innovative framework of Pervasive Service-Oriented Networks (PERSON). The core idea is to utilize a heterogeneous network as the information infrastructure, abstract the functionalities into services, and deploy context-aware intelligence to address the system dynamics. Furthermore, based on the framework of PERSON, we implement a powerful yet cost-effective EMS. The effectiveness of the EMS is demonstrated by a demand response application. ©2010 IEEE.published_or_final_versionThe 1st IEEE International Conference on Smart Grid Communications (SmartGridComm 2010), Gaithersburg, MD., 4-6 October 2010. In Proceedings of the 1st SmartGridComm, 2010, p. 1-

Hybrid cargo-level tracking system for logistics

In this paper, we propose a hybrid cargo-level tracking system for logistics. We highlight the special system requirements, discuss the design issues and identify the design principles. Then we propose an innovative hybrid system. As far as we know, this is the first system that exploits both infrastructure-based and infrastructure-less positioning schemes for practical cargo-level tracking. Compared with existing systems, the proposed system provides a ubiquitous cargo-level tracking solution with enhanced availability, reliability, and lower total costs. © 2010 IEEE.published_or_final_versionThe 71st IEEE Vehicular Technology Conference (VTC2010-Spring), Taipei, Taiwan, 16-19 May 2010. In Proceedings of 71st IEEE-VTC (Spring), 2010, p. 1-

Adaptive video transmission for OFDMA systems

An adaptive framework is proposed for multi-user video transmission over orthogonal frequency division multiple access (OFDMA) systems. Utilizing the channel knowledge, a two-step heuristic sub-carrier assignment algorithm is proposed to achieve unequal error protection for the video data. The approach also solves the fairness issue among different users that may be caused by varying channel quality on different sub-carriers. Meanwhile, multi-user channel gain is also achieved. The proposed framework significantly improves the video transmission quality with little extra computational complexity and system overhead. ©2007 IEEE.published_or_final_versio

Adaptive sub-channel allocation based UEP for video transmission in space-time coded OFDM systems

In this work, we introduce the idea of adaptive sub-channel allocation based unequal error protection (ASCA-UEP) to a space-time block coded orthogonal frequency division multiplexing (STBC-OFDM) system. In such a system, UEP is realized by adaptively allocating and transmitting high-priority and low-priority video data over high-quality and low-quality sub-channels, respectively. Further, we propose two ASCA-UEP schemes in a time division duplex (TDD) system: a receiver-based scheme and a transmitter-based scheme. Analysis and simulation results demonstrate that ASCA-UEP greatly enhances the quality of video reception, and the transmitter-based scheme is more robust to uplink channel noise than the receiver-based scheme, and is thus preferred when the receiver is power-constrained and the transmitter has sufficient power.published_or_final_versio

Unequal error protection for MIMO systems with a hybrid structure

We propose a hybrid multiple-input-multiple-output (MIMO) architecture to implement unequal error protection (UEP) for video delivery in MIMO systems. On the transmitter side, some of the transmit antennas are used to implement transmit diversity for delivering video data with high priority, while others are employed for spatial multiplexing to transmit video data with low priority. On the receiver side, a hybrid signal detection mechanism is adopted to separate and decode the mixed data. The goal is to exploit the diversity gain to provide better protection to the high priority data, while transmitting the low priority data with spatial multiplexing to achieve high data rate. Analysis and simulation results demonstrate that the proposed UEP mechanism significantly enhances the quality of video reception with a high spectrum efficiency. © 2006 IEEE.published_or_final_versio

The effect of interaction between Lipoprotein Lipase and ApoVLDL-II genes on fat and serum biochemical levels

Body weight, abdominal fat weight and serum biochemical levels were determined from lean and fat chicken breeds at 12 weeks of age. Single nucleotide polymorphism (SNP) in apoVLDL-II and lipoprotein lipase genes was screened by PCR-SSCP and detected by direct sequencing. Lipoprotein lipase gene frequency was found to be significantly different (P < 0.01) in lean chicken whereas it was non-significantly different in fat chicken. SNP in apoVLDL-II and lipoprotein lipase genes significantly (P< 0.05) affected body weight and fat weight. Similarly their interaction significantly (P < 0.05) affected body weight and fat weight. However, no significant difference was observed in the percentage of abdominal fat. SNP in apoVLDL-II and lipoprotein lipase genes significantly (P < 0.05) affected total cholesterol and high density lipoprotein. More likely, the interaction of apoVLDL-II and lipoprotein lipase significantly affect total cholesterol, triglyceride, high density lipoprotein, very low density lipoprotein and low density lipoprotein

An Efficient Approximate kNN Graph Method for Diffusion on Image Retrieval

The application of the diffusion in many computer vision and artificial intelligence projects has been shown to give excellent improvements in performance. One of the main bottlenecks of this technique is the quadratic growth of the kNN graph size due to the high-quantity of new connections between nodes in the graph, resulting in long computation times. Several strategies have been proposed to address this, but none are effective and efficient. Our novel technique, based on LSH projections, obtains the same performance as the exact kNN graph after diffusion, but in less time (approximately 18 times faster on a dataset of a hundred thousand images). The proposed method was validated and compared with other state-of-the-art on several public image datasets, including Oxford5k, Paris6k, and Oxford105k

Detecting dynamic communities in opportunistic networks

In opportunistic networks, communities of mobile entities may be utilized to improve the efficiency of message forwarding. However, identifying communities that are dynamically changing in mobile environment is non-trivial. Based on random walk on graphs, in this paper we present a community detection algorithm that takes into account the aging and weight of contacts between mobile entities. Our idea originates from message-forwarding operations in opportunistic networks. We evaluate the algorithm on both computer-generated networks and real-world human mobility traces. The result shows that our proposed algorithm can find the communities and detect the changes in their structures over time. © 2009 IEEE.published_or_final_versionThe 1st International Conference on Ubiquitous and Future Networks (ICUFN 2009), Hong Kong, China, 7-9 June 2009. In Proceedings of the 1st ICUFN, 2009, p. 159-16

Reactive interface formation and Co-induced (√7×√7 ) superstructure on a GaN(0001) pseudo- (1×1 ) substrate surface

Deposition of Co on GaN(0001) pseudo- (1×1) surface at room temperature by molecular-beam epitaxy is studied by low-energy electron diffraction, scanning-tunneling microscopy and first-principles total energy calculations. Reactive interface formation where the deposited Co reacts with Ga on GaN substrate forming CoGax (x∼2) compound or alloy can be inferred from surface morphology evolution and mass consideration. At an intermediate coverage about 0.4 monolayers, a specific (√7×√7) surface structural phase develops, as observed by both low-energy electron diffraction and scanning tunneling microscopy studies. First-principles total energy calculations suggest that the (√7×√7) structure is induced by Co-trimers located slightly below the topmost Ga adlayer of the substrate. © 2010 The American Physical Society.published_or_final_versio