Adaptive-and-Resolvable Fractional Repetition Codes Based on Hypergraph

Tiantian Wang,Jing Wang,Haipeng Wang,Jie Meng,Chunlei Yu,Shuxia Wang 한국인터넷정보학회 2023 KSII Transactions on Internet and Information Syst Vol.17 No.4

Fractional repetition (FR) codes can achieve exact uncoded repair for multiple failed nodes, with lower computational complexity and bandwidth overhead, and effectively improve repair performance in distributed storage systems (DSS). The actual distributed storage system is dynamic, that is, the parameters such as node storage overhead and number of storage nodes will change randomly and dynamically. Considering that traditional FR codes cannot be flexibly applied to dynamic distributed storage systems, a new construction scheme of adaptive-and-resolvable FR codes based on hypergraph coloring is proposed in this paper. Specifically, the linear uniform regular hypergraph can be constructed based on the heuristic algorithm of hypergraph coloring proposed in this paper. Then edges and vertices in hypergraph correspond to nodes and coded packets of FR codes respectively, further, FR codes is constructed. According to hypergraph coloring, the FR codes can achieve rapid repair for multiple failed nodes. Further, FR codes based on hypergraph coloring can be generalized to heterogeneous distributed storage systems. Compared with Reed-Solomon (RS) codes, simple regenerating codes (SRC) and locally repairable codes (LRC), adaptive-and-resolvable FR codes have significant advantages over repair locality, repair bandwidth overhead, computational complexity and time overhead during repairing failed nodes.

Design of 39-GHz Up- and Down-Conversion Mixers for 5G mmWave TDD Applications

Wang Yi-Yang,Duan Haipeng,He Long,Wu Xu,Wang Dongming,Li Lianming 한국전자파학회 2023 Journal of Electromagnetic Engineering and Science Vol.23 No.2

This article presents fully integrated 39-GHz bidirectional up- and down-conversion mixers for 5G millimeter-wave (mmWave) applications. Fabricated in a 65-nm CMOS process with a 1.2-V supply voltage, the up- and down-conversion mixers consume 39 and 43 mW, respectively. For 5G time-division duplexing (TDD) operation, intermediate-frequency (IF)/local-oscillator (LO)/radio-frequency (RF) T/R switches are introduced. For better isolation and low insertion loss between the up- and down-conversion mixer, a series-shunt singlepole double-throw (SPDT) structure and an equivalent lumped λ/4 transmission line are proposed for IF and RF T/R switches, respectively. To realize compact area and wide bandwidth, a transformer-based matching network is adopted in this design. Targeting multi-channel phased array applications, the measurement result shows that the up-conversion mixer achieves a 2.5-dB peak conversion gain with 6.5 GHz 3-dB bandwidth. Including the insertion loss of the switch and IF signal routing, at the maximum gain of 36.5 GHz, the up-conversion mixer achieves an output 1-dB gain compression point (OP1dB) of 2.5 dBm. Furthermore, the down-conversion mixer achieves a 5-dB peak conversion gain with a 9.7-GHz 3-dB bandwidth.

A Keyword Filters Method for Spam via Maximum Independent Sets

HaiLong Wang,FanJun Meng,HaiPeng Jia,JinHong Cheng,Jiong Xie 보안공학연구지원센터 2013 International Journal of Smart Home Vol.7 No.3

Determination of meaty peptide in enzymatic hydrolyzate of beef protein by HPLC-MS

Yanping Wang,Songrong Zeng,Xiaojia Bai,Weili Lin,Ming Yang,Haipeng Xing 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.5

The purpose of this study is to detect beefy meaty peptide (BMP) in beef hydrolyzate. The synthesized BMP is used as a standard sample in the study. High performance liquid chromatography (HPLC)/ion trap electrospray ionization mass spectrometry (ESI-MS) with UV detection was applied in qualitative analysis of the peptides. Six beef protein enzymatic hydrolyzate samples were separated on a Surveyor HPLC system through a SUPELCO Discovery® C18 analytical column (5 μm, 15 cm×2.1 mm i.d.). The column was eluted at a flow rate of 0.2 mL/min in a linear gradient elution mode of acetronitrile-water solution with 0.1% trifluoroacetic acid. The concentration of acetronitrile was increased from 5% to 50% in 40 minutes. A Finnigan LCQ Advantage MAX instrument was used as detector to analyze with ESI-MS and ESI-MS/MS in positive mode. Among the six samples of beef protein enzymatic hydrolysate, the BMP is detected and confirmed in sample No.4 with a higher intensity of characteristic peak and is further investigated by ESI-MS/MS. As a result, BMP exists in sample No.4. The study proves that HPLC-ESI-MS/MS is a simple, rapid, sensitive method to analyze target peptides from complex polypeptides

Experimental and numerical research on cavitating flows around axisymmetric bodies

Wei Haipeng,Fu Song,Wu Qin,Huang Biao,Wang Guoyu 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.11

We investigated the cavitating flows around different axisymmetric bodies based on experiments and numerical simulation. In the numericalsimulation, the multiphase Reynolds averaged Navier Stokes equations (RANS) were solved via the commercial computationalfluid dynamics code CFX. The modified k-w SST turbulence model was used along with the transport equation-based cavitation model. In the experiments, a high-speed video technique was used to observe the unsteady cavitating flow patterns, and the dynamic force measurementsystem was used to measure the hydrodynamics of the axisymmetric bodies under different cavitation conditions. Results areshown for the hemisphere bodies, conical bodies and blunt bodies. Reasonable agreements were obtained between the computational andexperimental results. The results show that for the hemispherical body, the cavity consists of quasi-steady transparent region and unsteadyfoggy water-vapor mixture region, which contains small-scale vortices and is dominated by bubble clusters, causing irregulardisturbances at the cavity interfaces. The curvature at the front of the conical body is larger, resulting in that the flow separates at theshoulder of the axisymmetric body. The cavity stretches downstream and reaches to a fixed cavity length and shape. For blunt bodies, theincipient cavitation number is larger than that for the hemispherical body. A large cloud cavity is formed at the shoulder of the blunt bodyin the cores of vortices in high shear separation regions and the re-entrant jet does not significantly interact with the cavity interface whenit moves upstream. As to the dynamic characteristics of unsteady cavitating flows around the axisymmetric bodies, the pulsation frequencyfor the hemispherical body is larger than that for the blunt body. For the hemispherical body, the pulsation is mainly caused bythe high-frequency, small-scale shedding at the rear end of the cavity, while for the blunt body, the main factor for the pulsation frequencyis the periodically shedding of large-scale vortex cavities.

Assessment of supervision monitoring for radiation environment around the typical research reactors in China

Sa Li,Haipeng Wang,Yanxia Zhang 한국원자력학회 2021 Nuclear Engineering and Technology Vol.53 No.12

The supervision mode, monitoring basis and monitoring scheme of radiation environment monitoringconcerning typical research reactors in China were investigated in this study. Summary and analysis wereconcluded of the present situation of supervised monitoring of radiation environment, such as monitoring objects, points, frequency and so on, based on the relevant data of monitoring points of fourtypical research reactors in China. Some experiences and existing problems were analyzed concerningthe supervised monitoring of China's research reactors. Tips on topics related to strengthen the monitoring of radiation environment around the research reactors has noted.

FINITE p-GROUPS WHOSE NON-CENTRAL CYCLIC SUBGROUPS HAVE CYCLIC QUOTIENT GROUPS IN THEIR CENTRALIZERS

Zhang, Lihua,Wang, Jiao,Qu, Haipeng Korean Mathematical Society 2015 대한수학회보 Vol.52 No.2

In this paper, we classified finite p-groups G such that $$C_G(x)/<x>$$ is cyclic for all non-central elements $x{\in}G$. This solved a problem proposed By Y. Berkovoch.

Surface Coating of Polytetrafluoroethylene with Extracellular Matrix and Anti-CD34 Antibodies Facilitates Endothelialization and Inhibits Platelet Adhesion Under Sheer Stress

Lei Chen,Haipeng He,Mian Wang,Xiaoxi Li,Henghui Yin 한국조직공학과 재생의학회 2017 조직공학과 재생의학 Vol.14 No.4

Expanded polytetrafluoroethylene (ePTFE) polymers do not support endothelialization because of nonconductive characteristics towards cellular attachment. Inner surface modification of the grafts can improve endothelialization and increase the long-term patency rate of the ePTFE vascular grafts. Here we reported a method of inner-surface modification of ePTFE vascular graft with extracellular matrix (ECM) and CD34 monoclonal antibodies (CD34 mAb) to stimulate the adhesion and proliferation of circulating endothelial progenitor cells on ePTFE graft to enhance graft endothelialization. The inner surface of ECM-coated ePTFE grafts were linked with CD34 mAb in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) solution and the physicochemical properties, surface morphology, biocompatibility, and hemocompatibility of the grafts were studied. The hydrophilicity of CD34 mAb-coated graft inner surface was significantly improved. Fourier transform infrared spectroscopy analysis confirmed ECM and CD34 mAb cross-linking in the ePTFE vascular grafts with our method. Scanning electron microscopy analysis showed protein layer covering uniformly on the inner surface of the modified grafts. The cell-counting kit-8 (CCK-8) assay confirmed that the modified graft has no obvious cytotoxicity. The modified graft showed a low hemolytic rate (0.9%) in the direct contact hemolysis test, suggesting the modification improved hemocompatibility of biopolymers. The modification also decreased adhesion of platelets, while significantly increased the adhesion of endothelial cells on the grafts. We conclude that our method enables ePTFE polymers modification with ECM and CD34 mAb, facilitates endothelialization, and inhibits platelet adhesion on the grafts, thus may increase the long-term patency rate of the prosthetic bypass grafts.

Android Permissions Management at App Installing

Sujit Biswas,Wang Haipeng,Javed Rashid 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.3

Android based smartphone users’ privacy has been a hot issue recently in public concerns due to various instances of security attacks and privacy leakage on Android platform. Android existing security has been built upon a permission based mechanism which restricts critical resources accesses of third-party Android applications. This permission based security system is widely assessed for its major control of application permissions and critical management of permissions by developers, marketers, and end-users. Considering the critical management of permissions some previous research papers proposed automatic permission management tools. But those automatic tools never assessed end user’s expectation about permissions perfectly. This paper presents a tool, SDroid (Secured anDroid) that assesses the best permissions management based on end users opinion. SDroid evaluates requested permissions and allow users selectively grant permissions considering his/her knowledge level depending on the opinion.

Least squares sieve estimation of mixture distributions with boundary effects

Mihee Lee,Ling Wang,Haipeng Shen,Peter Hall,Guang Guo,J.S. Marron 한국통계학회 2015 Journal of the Korean Statistical Society Vol.44 No.2

In this study, we propose two types of sieve estimators, based on least squares (LS), for probability distributions that are mixtures of a finite number of discrete atoms and a continuous distribution under the framework of measurement error models. This research is motivated by the maximum likelihood (ML) sieve estimator developed in Lee et al. (2013). We obtain two types of LS sieve estimators through minimizing the distance between the empirical distribution/characteristic functions and the model distribution/characteristic functions. The LS estimators outperform the ML sieve estimator in several aspects: (1) they need much less computational time; (2) they give smaller integrated mean squared error; (3) the characteristic function based LS estimator is more robust against mis-specification of the error distribution. We also use roughness penalization to improve the smoothness of the resulting estimators and reduce the estimation variance. As an application of our proposed LS estimators, we use the Framingham Heart Study data to investigate the distribution of genetic effects on body mass index. Finally asymptotic properties of the LS estimators are investigated.