Dynamic Power Splitting Policies for AF Relay Networks with Wireless Energy Harvesting

Wireless energy harvesting (WEH) provides an exciting way to supply energy for relay nodes to forward information for the source-destination pairs. In this paper, we investigate the problem on how the relay node dynamically adjusts the power splitting ratio of information transmission (IT) and energy harvesting (EH) in order to achieve the optimal outage performance. According to the knowledge of channel state information (CSI) at the relay, optimal dynamic power splitting policy with full CSI and partial CSI are both provided. Finally, through simulations, the proposed power splitting policies can improve the outage performances and the policy with full CSI achieves the best performance. It is also shown that the policy with partial CSI can approach the policy with full CSI closely and incurs far less system overhead.Comment: accepted by IEEE ICC 2015 - Workshop on Green Communications and Networks with Energy Harvesting, Smart Grids, and Renewable Energie

Bio-Inspired Micromachined Volumetric Flow Sensor with a Big Dynamic Range for Intravenous Systems

Real-time monitoring of drug delivery in an intravenous infusion system can prevent injury caused by improper drug doses. As the medicine must be administered into the vein at different rates and doses in different people, an ideal intravenous infusion system requires both a low flow rate and large dynamic range monitoring. In this study, a bio-inspired and micromachined volumetric flow sensor is presented for the biomedical application of an intravenous system. This was realized by integrating two sensing units with different sensitivities on one silicon die to achieve a large dynamic range of the volumetric flow rate. The sensor was coated with a parylene layer for waterproofing and biocompatibility purposes. A new packaging scheme incorporating a silicon die into a flow channel was employed to demonstrate the working prototype. The test results indicate that the sensor can detect a volumetric flow rate as low as 2 mL/h, and its dynamic range is from 2 mL/h to 200 mL/h. The sensor performed better than the other two commercial sensors for low-flow detection. The high sensitivity, low cost, and small size of this flow sensor make it promising for intravenous applications

An insight into the mechanism and evolution of shale reservoir characteristics with over-high maturity

AbstractOver-high maturity is one of the most vital characteristics of marine organic-rich shale reservoirs from the Lower Paleozoic in the south part of China. The organic matter (OM) in shale gas reservoirs almost went through the entire thermal evolution. During this wide span, a great amount of hydrocarbon was available and numerous pores were observed within the OM including kerogen and solid bitumen/pyrobitumen. These nanopores in solid bitumen/pyrobitumen can be identified using SEM. The imaging can be dissected and understood better based on the sequence of diagenesis and hydrocarbon charge with the shape of OM and pores. In terms of the maturity process showed by the various typical cases, the main effects of the relationship between the reservoir porosity and organic carbon abundance are interpreted as follows: the change and mechanism of reservoirs properties due to thermal evolution are explored, such as gas carbon isotope from partial to complete rollover zone, wettability alteration from water-wet to oil-wet and then water-wet pore surface again, electrical resistivity reversal from the increasing to decreasing stage, and nonlinearity fluctuation of rock elasticity anisotropy. These indicate a possible evolution pathway for shale gas reservoirs from the Lower Paleozoic in the southern China, as well as the general transformation processes between different shale reservoirs in thermal stages

The Spirit of Individualism: Avant-Garde Art in Shanghai 1979-1989

This thesis is a study of avant-garde art in Shanghai from 1979 to 1989 and the role that it played in contemporary art in mainland China in the 1980s. The artists and art administrators discussed in this thesis, I argue, were at the forefront of the development of contemporary art in China through artistic experimentations and institutional engagement in avant-garde art activities. Contemporary Chinese art emerged in the international arena in the early 1990s and began to attract the attention of art professionals and collectors. It went on to become a strong force globally in the first decade of the new millennium. Its emergence in this timeframe mirrors another Chinese phenomenon -- that of the revitalisation of Shanghai to lead China's economic development trajectory onto the world stage. These Chinese phenomena signify the 1980s, the decade following the end of the Cultural Revolution in 1976, through unprecedented political and economic reforms with their transforming impact on art and culture, as being critical to the study of contemporary art in China. Shanghai, with its semi-colonial, political, economic and cultural history, including the strong legacy of the early twentieth-century modernist art movement, has played a vital role in China's modernisation and presents itself as a unique case in the evolution of contemporary art in China. Art historians and critics, both in China and internationally in recent years, have been increasingly interested in exploring contemporary Chinese art in the 1980s. From my observations and my research findings, avant-garde art in Shanghai in the 1980s has nevertheless been neglected in the discourse and still lacks in-depth scholarly study. This thesis is intended to fill this lacuna in the narratives of China's contemporary art history. It is based on empirical evidence from my personal experiences as a practising artist in Shanghai during this period, my long-term friendship with key artists and art administrators and writers, and extensive new research I have undertaken. In this thesis, Shanghai avant-garde art in the 1980s is examined through case studies of the Shanghai Art Museum and six artists: Zhang Jianjun, Li Shan, Yu Youhan, Chen Zhen, Cai Guoqiang and Gu Wenda. I argue that the essence of avant-garde art in Shanghai in the 1980s was the quality of individualism displayed by artists who resisted the collectivist ethos in China in this period. These artists also retained strong historical connections to the early twentieth-century modernist art movement in Shanghai. I demonstrate in the thesis that these elements have been overlooked in the national and international discourse on contemporary Chinese art and that this has resulted in inadequate representations of the Shanghai avant-garde art in the decade of the 1980s in the art historiography of contemporary China

Characterization of the complete chloroplast genome of Clinopodium chinense (Labiatae), a medicinal plant in southwest of China

Clinopodium chinense is a medicinal plant commonly used in southwest of China. In this study, we sequenced the complete chloroplast (cp) genome sequence of C. chinense to investigate its phylogenetic relationship in the family Labiatae. The chloroplast genome of C. chinense was 151,989 bp in length with 37.8% overall GC content, including a large single copy (LSC) region of 83,189 bp, a small single copy (SSC) region of 17,642 bp and a pair of inverted repeats (IRs) of 25,579 bp. The cp genome contained 113 genes, including 80 protein coding genes, 29 tRNA genes, and 4 rRNA genes. The phylogenetic analysis indicated Clinopodium was closely related to Mentha

The complete chloroplast genome sequence of the medicinal plant Elsholtzia rugulosa Hemsl (Labiatae)

Elsholtzia rugulosa is a medicinal plant commonly used in southwest of China. In this study, we sequenced the complete chloroplast (cp) genome sequence of E. rugulosa to investigate its phylogenetic relationship in the family Labiatae. The chloroplast genome of E. rugulosa was 151,952 bp in length with 37.9% overall GC content, including a large single copy (LSC) region of 83,056 bp, a small single copy (SSC) region of 17,526 bp, and a pair of inverted repeats (IRs) of 25,685 bp. The cp genome contained 113 genes, including 80 protein-coding genes, 29 tRNA genes, and 4 rRNA genes. The phylogenetic analysis indicated Elsholtzia was closely related to Perilla

Versatile Approach of Silicon Nanofabrication without Resists: Helium Ion-Bombardment Enhanced Etching

Herein, we report a helium ion-bombardment enhanced etching method for silicon nanofabrication without the use of resists; furthermore, we demonstrate its unique advantages for straightforward fabrication on irregular surfaces and prototyping nano-electro-mechanical system devices, such as self-enclosed Si nanofluidic channels and mechanical nano-resonators. This method employs focused helium ions to selectively irradiate single-crystal Si to disrupt the crystal lattice and transform it into an amorphous phase that can be etched at a rate 200 times higher than that of the non-irradiated Si. Due to the unique raindrop shape of the interaction volumes between helium ions and Si, buried Si nanofluidic channels can be constructed using only one dosing step, followed by one step of conventional chemical etching. Moreover, suspended Si nanobeams can be fabricated without an additional undercut step for release owing to the unique raindrop shape. In addition, we demonstrate nanofabrication directly on 3D micro/nano surfaces, such as an atomic force microscopic probe, which is challenging for conventional nanofabrication due to the requirement of photoresist spin coating. Finally, this approach can also be extended to assist in the etching of other materials that are difficult to etch, such as silicon carbide (SiC)

Bio-Inspired Micromachined Volumetric Flow Sensor with a Big Dynamic Range for Intravenous Systems

Real-time monitoring of drug delivery in an intravenous infusion system can prevent injury caused by improper drug doses. As the medicine must be administered into the vein at different rates and doses in different people, an ideal intravenous infusion system requires both a low flow rate and large dynamic range monitoring. In this study, a bio-inspired and micromachined volumetric flow sensor is presented for the biomedical application of an intravenous system. This was realized by integrating two sensing units with different sensitivities on one silicon die to achieve a large dynamic range of the volumetric flow rate. The sensor was coated with a parylene layer for waterproofing and biocompatibility purposes. A new packaging scheme incorporating a silicon die into a flow channel was employed to demonstrate the working prototype. The test results indicate that the sensor can detect a volumetric flow rate as low as 2 mL/h, and its dynamic range is from 2 mL/h to 200 mL/h. The sensor performed better than the other two commercial sensors for low-flow detection. The high sensitivity, low cost, and small size of this flow sensor make it promising for intravenous applications

Design and analysis of a multiple sensor units vector hydrophone

Inspired by the hairy structure of fish neuromast, a multiple sensor units (multi-unit) vector hydrophone is proposed in the paper, which integrates multiple sensor units on one chip according to bionics. Its sensitivity and signal noise ratio (SNR) are theoretically analyzed compared with the hydrophone which has only one sensor unit. In order to verify the correctness of the theory, a 4-unit vector hydrophone has been fabricated. For experiments, the comparative calibration experiment is used to validate the theoretical analysis of sensitivity and fast fourier transform algorithm (FFT) is used to process the experiment data to verify the theoretical analysis of SNR. The results show that the sensitivity of the 4-unit hydrophone is improved by 11.8 dB and the SNR is improved by 1.9 dB on average, which is correlated with the theoretical analysis