PoW-BC: A PoW Consensus Protocol Based on Block Compression

( Bin Yu ),( Xiaofeng Li ),( He Zhao ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.4

Proof-of-Work (PoW) is the first and still most common consensus protocol in blockchain. But it is costly and energy intensive, aiming at addressing these problems, we propose a consensus algorithm named Proof-of-Work-and-Block-Compression (PoW-BC). PoW-BC is an improvement of PoW to compress blocks and adjust consensus parameters. The algorithm is designed to encourage the reduction of block size, which improves transmission efficiency and reduces disk space for storing blocks. The transaction optimization model and block compression model are proposed to compress block data with a smaller compression ratio and less compression/ decompression duration. Block compression ratio is used to adjust mining difficulty and transaction count of PoW-BC consensus protocol according to the consensus parameters adjustment model. Through experiment and analysis, it shows that PoW-BC improves transaction throughput, and reduces block interval and energy consumption.

MPC-based FTC with FDD against Actuator Faults of UAVs

Bin Yu,Youmin Zhang,Yaohong Qu 제어로봇시스템학회 2015 제어로봇시스템학회 국제학술대회 논문집 Vol.2015 No.10

The increasing development of unmanned aerial vehicles (UAVs) and the requirements of high autonomy and safety levels require that the controller of UAVs should possess fault-tolerant/reconfigurable function to accommodate unpredicted situations such as actuator faults, sensor faults, or aircraft damage. This paper addresses the partial loss of control effectiveness (LOE) of actuators in a quadrotor UAV using model predictive control (MPC) with terminal constraints, which allows to track a reference command even if in the presence of actuator faults. The proposed faulttolerant control system (FTCS) adopts MPC technique to design fault-tolerant controller and state-augmented Kalman filter (SAKF) to achieve fault detection and diagnosis (FDD) function. Simulation results based on a quadrotor UAV demonstrate that the proposed fault-tolerant controller has a good performance in accommodating actuator faults.

레이더 흡수특성이 있는 저적외선 방출 복합섬유의 제조 및 특성 연구

Bin Yu,Lu Qi 한국고분자학회 2006 폴리머 Vol.30 No.2

Optimal Amplify-and-Forward Scheme for Parallel Relay Networks with Correlated Relay Noise

Binyue Liu,Ye Yang 한국전자통신연구원 2014 ETRI Journal Vol.36 No.4

This paper studies a parallel relay network where therelays employ an amplify-and-forward (AF) relayingscheme and are subjected to individual power constraints. We consider correlated effective relay noise arising frompractical scenarios when the relays are exposed tocommon interferers. Assuming that the noise covarianceand the full channel state information are available, weinvestigate the problem of finding the optimal AF schemein terms of maximum end-to-end transmission rate. It isshown that the maximization problem can be equivalentlytransformed to a convex semi-definite program, which canbe efficiently solved. Then an upper bound on themaximum achievable AF rate of this network is providedto further evaluate the performance of the optimal AFscheme. It is proved that the upper bound can beasymptotically achieved in two special regimes when thetransmit power of the source node or the relays issufficiently large. Finally, both theoretical and numericalresults are given to show that, on average, noisecorrelation is beneficial to the transmission rate —whether the relays know the noise covariance matrix or not.

A Lifetime Estimation Method of MMC Submodules Based on the Combination of FEA and Physical Lifetime Model

Binyu Wang,Jianpeng Wang,Dingkun Ma,Laili Wang,Fengtao Yang,Xinying Li,Youbo Tan 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

Due to a series of advantages compared with other existing power converters, modular multilevel converters (MMCs) have been widely used in the last decade. However, in some applications, such as the offshore wind power transmission, the MMC submodules (SMs) are subjected to harsh operating environment and adverse mission profiles which can easily lead to failures in the solder layers of IGBT modules. Therefore, the lifetime estimation is very important to predict the reliability of MMC. This paper studies the fundamental-frequency thermal cycles and proposes a lifetime estimation method of MMC SMs based on the combination of finite element analysis (FEA) and the physical lifetime model. This method provides a deeper physical description of the failure mechanism and considers the thermal coupling among the chips, which make the lifetime calculation more accurate. The simulation time of FE in this research is acceptable. The distribution of lifetime is presented in the form of a colorful cloud map, rather than a single number, from which we can know the most vulnerable part of the solder layers. This can help us find the appropriate measures to improve the reliability of MMC SMs. In this paper, the principle and reliability issues of MMC are first analyzed. Second, the loss of the SM is calculated through simulation and curve fitting. Then, a 3D finite element (FE) model of MMC SM is developed and the FE simulation is performed. Finally, the lifetime of the SM is obtained based on the FEA results and Morrow lifetime model.

Rhombohedraleorthorhombic phase coexistence and electrical properties of Ta and BaZrO3 co-modified (K, Na)NbO3 lead-free ceramics

Binyu Zhang,Jiagang Wu,Xiaopeng Wang,Xiaojing Cheng,Jianguo Zhu,Dingquan Xiao 한국물리학회 2013 Current Applied Physics Vol.13 No.8

The BaZrO3 and Ta have been used to improve piezoelectric properties of (K, Na)NbO3 ceramics by the construction of the phase boundary, and (1 x)K0.48Na0.52(Nb0.95Ta0.05)O3exBaZrO3 [(1 x)KNNTexBZ]ceramics were prepared by the conventional solid-state method. The effect of BZ content on their phase structure, microstructure, and electrical properties has been investigated. A rhombohedral and orthorhombic phase coexistence has been observed in the compositional range of 0.05 x 0.07. With increasing BZ content, their Tc and Toet values decrease gradually, and the dielectric constant increases linearly. The ceramic with x ¼ 0.06 exhibits an enhanced piezoelectric behavior (d33 w 193 pC/N and kp w 32.6%) because of the coexistence of two phases together with a dense microstructure. As a result,the construction of a rhombohedral and orthorhombic phase boundary is an effective way to improve the piezoelectric properties of KNN-based ceramics.

Expression of microRNAs associated with oxidative stress in the hippocampus of piglets

Binyu Yang,Hongyuan Mei,Fuyuan Zuo,Ling Gan 한국유전학회 2017 Genes & Genomics Vol.39 No.7

Oxidative stress is associated with human diseases and the developmental retardation of animals. The hippocampus is particularly vulnerable to oxidative stress. MicroRNAs (miRNAs), expressed largely in the mammalian brain, are emerging as robust players and have been implicated in many cellular processes. The present study investigated the sub-tissue specificity of miRNA expression in the dorsal hippocampus (DH) and ventral hippocampus (VH) and evaluated the effects of oxidative stress induced by iron dextran (FeDex) treatment on miRNA expression in the DH and VH of pigs using RNA-sequencing technology and bioinformatics, respectively. The results demonstrated that the injection of FeDex significantly increased the levels of several markers of oxidative stress in serum of Rongchang piglets, which indicated that oxidative stress was successfully induced. Sub-tissue specificity was displayed with 54 differentially expressed miRNAs between the VH and DH. The induced oxidative stress emphasized 59 and 46 differentially expressed miRNAs in the DH and VH, respectively. GO and KEGG pathway analyses revealed that the predicted targets of these differentially expressed miRNAs were involved in the pathways that regulate the expression of genes associated with nervous system development, immune response and oxidative stress, which not only revealed the ability of miRNAs to influence complex gene networks in the DH and VH but also further corroborated the successful induction of oxidative stress. Collectively, the results of this study provide a valuable basis for future studies aimed at contributions of miRNAs induced by oxidative stress in growth retardation and neurodegenerative diseases of animals and human.

Design of Distributed Beamforming for Dual-Hop Multiple-Access Relay Networks

Binyue Liu 한국전자통신연구원 2014 ETRI Journal Vol.36 No.4

This paper studies a dual-hop multiple-access relaynetwork where two independent source nodes transmitinformation to a common destination node with the aid ofmultiple single-antenna amplify-and-forward relays. Eachrelay node is subject to an individual power constraint. Wefocus on the design of distributed beamforming schemesfor the relays to support the transmission raterequirements of the two sources. To this end, we firstcharacterize the achievable rate region for this networkvia solving a sequence of corner point optimizationproblems proposed in this paper. We also develop severallow-complexity suboptimal schemes in closed form. Twoinner bounds of the achievable rate region aretheoretically shown to be approximately optimal in twospecial scenarios. Finally, numerical results demonstratethe effectiveness of our proposed approaches.

A Fluorenone Alkaloid from Caulophyllum robustum Maxim. with Anti-myocardial Ischemia Activity

Sicen Wang,Binyu Wen,Na Wang,Juntian Liu,Langchong He 대한약학회 2009 Archives of Pharmacal Research Vol.32 No.4

A new fluorenone alkaloid (caulophine) was isolated from the radix of Caulophyllum robustumMaxim. (collected from the Qinling mountains) using cell membrane chromatography as the screening method. Caulophine was identified as 3-(2-(dimethylamino)ethyl)-4,5-dihydroxy-1,6-dimethoxy-9H-fluoren-9-one based on physicochemic and spectroscopic analyses, particularly by NMR spectroscopic data (i.e., COSY, HMQC, HMBC, NOESY). Caulophine possessed anti-myocardial ischemia activity.

The effect of iron dextran on the transcriptome of pig hippocampus

Ling Gan,Binyu Yang,Hongyuan Mei 한국유전학회 2017 Genes & Genomics Vol.39 No.1

The chain of events resulting from oxidative stress is still barely understood. The hippocampus is particularly vulnerable to oxidative stress. With the emergence of high-throughput sequencing, many different biological components can be discovered simultaneously. Using RNA-seq technology, we conducted a whole-transcriptome analysis of the hippocampi of piglets exposed to iron dextran (FeDex), a potent inducer of oxidation stress. The total hippocampal RNA from the piglets was sequenced, and 11.5 Gb of sequencing data were obtained. Regulatory molecules involved in oxidative stress were determined through the identification of 362 differentially expressed genes (DEGs). The functional analysis revealed that these DEGs were primarily involved in the defense response and responses to external stimuli. Furthermore, 76 neuropeptide gene transcripts and 60 neuropeptide receptor gene transcripts were identified in the hippocampus. Of these transcripts, the mRNA levels of six neuropeptide genes were significantly changed. Overall, this study describes the first use of RNA-seq to elucidate the transcriptomic changes in the piglet hippocampus caused directly by the injection of iron dextran, which enabled the characterization of the transcriptional response triggered by oxidative stress.