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BlockHDFS:Blockchain-integrated Hadoop distributed file system for secure provenance traceability

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Blockchain(Research and Applications) 2021年第4期2卷 30-36页

作者： Viraaji mothukuri Sai S.Cheerla Reza m.Parizi Qi Zhang Kim-kwang Raymond Choo College of Computing and Software Engineering Kennesaw State UniversityKennesawGA30144USA IBm Thomas J.Research Center Yorktown HeightsNY10598USA Department of Information Systems and Cyber Security University of Texas at San AntonioSan AntonioTX78249USA

Hadoop Distributed File System(HDFS)is one of the widely used distributed file systems in big data analysis for frameworks such as *** allows one to manage large volumes of data using low-cost commodity ***,vulnerabilities in HDFS can be exploited for nefarious *** reinforces the importance of ensuring robust security to facilitate file sharing in Hadoop as well as having a trusted mechanism to check the authenticity of shared *** is the focus of this paper,where we aim to improve the security of HDFS using a blockchain-enabled approach(hereafter referred to as BlockHDFS).Specifically,the proposed BlockHDFS uses the enterprise-level Hyperledger Fabric platform to capitalize on files'metadata for building trusted data security and traceability in HDFS.

关键词： Big data Hadoop Blockchain Hyperledger fabric Hadoop distributed file system(HDFS) Traceability Security Privacy

Inhibitory effects of polysaccharides isolated from Phellinus gilvus on benzo(a)pyrene-induced forestomach carcinogenesis in mice

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World Journal of Gastroenterology 2005年第4期11卷 577-579页

作者： Jae-Sung Bae kwang-Ho Jang Hyunee Yim Seung-Chun Park hee-Kyung Jin College of Veterinary medicine Kyungpook National University Daegu 702-701 Republic of Korea Department of Pathology Ajou University School of medicine Suwon Republic of Korea

AIm: Although polysaccharides from Phellinus mushrooms are a well-known material with anti-tumor properties, there is no information about the effect of polysaccharides from Phellinus gilvus (PG) on tumor. The modulating effect of polysaccharides isolated from PG on the benzo(a)pyrene (BaP)-induced forestomach carcinogenesis in ICR female mice was investigated in this ***: A forestomach carcinogenesis model was established in 40 ICR female mice receiving oral administration of BaP for 4 wk. The mice were randomly assigned to 4 groups (10 each). The mice in each group were treated with sterile water or PG for 4 and 8 wk (SW4,PGW4, SW8, and PGW8 groups). Eight or 12 wk after the first dose of BaP, forestomachs were removed for histopathological and RT-PCR ***: In histopathological changes and RT-PCR analysis, sterile water-treated mice showed significant hyperplasia of the gastric mucosa with a significantly increased expression of mutant p53 mRNA compared to mice treated with PG for 8 ***: Polysaccharides isolated from PG may inhibit BaP-induced forestomach carcinogenesis in mice bydown-regulating mutant p53 expression.

关键词： Forestomach carcinogenesis Phellinus gilvus Polysaccharides p53 Gene

A systematic literature review of blockchain cyber security

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Digital Communications and Networks 2020年第2期6卷 147-156页

作者： Paul J.Taylor Tooska Dargahi Ali Dehghantanha Reza m.Parizi Kim-kwang Raymond Choo School of Computing Science&EngineeringUniversity of SalfordManchesterUK Cyber Science Lab School of Computer ScienceUniversity of GuelphOntarioCanada Department of Software Engineering and Game Development Kennesaw State UniversityMariettaGA30060USA Department of Information Systems and Cyber Security University of Texas at San AntonioSan AntonioTX78249USA

Since the publication of Satoshi Nakamoto's white paper on Bitcoin in 2008,blockchain has(slowly)become one of the most frequently discussed methods for securing data storage and transfer through decentralized,trustless,peer-to-peer *** research identifies peer-reviewed literature that seeks to utilize blockchain for cyber security purposes and presents a systematic analysis of the most frequently adopted blockchain security *** findings show that the Internet of Things(IoT)lends itself well to novel blockchain applications,as do networks and machine visualization,public-key cryptography,web applications,certification schemes and the secure storage of Personally Identifiable Information(PII).This timely systematic review also sheds light on future directions of research,education and practices in the blockchain and cyber security space,such as security of blockchain in IoT,security of blockchain for AI data,and sidechain security.

关键词： Blockchain Smart contracts Cyber security Distributed ledger technology IoT Cryptocurrency Bitcoin

micro-accelerometer Based on Vertically movable Gate Field Effect Transistor

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Nano-micro Letters 2015年第3期7卷 282-290页

作者： Heung Seok Kang Kang-hee Lee Dong-Youk Yang Byoung hee You In-Hyouk Song Korea Atomic Energy Research Institute LOGTECH Co. Ltd 914 Gumgang Hightech Valley 1st Department of Engineering Technology Texas State University601 University Dr. San Marcos TX 78666 USA

A vertically movable gate field effect transistor(VmGFET) is proposed and demonstrated for a microaccelerometer application. The VmGFET using air gap as an insulator layer allows the gate to move on the substrate vertically by external forces. Finite element analysis is used to simulate mechanical behaviors of the designed structure. For the simulation, the ground acceleration spectrum of the 1952 Kern County Earthquake is employed to investigate the structural integrity of the sensor in vibration. Based on the simulation, a prototype VmGFET accelerometer is fabricated from silicon on insulator wafer. According to current–voltage characteristics of the prototype VmGFET, the threshold voltage is measured to be 2.32 V, which determines the effective charge density and the mutual transconductance of1.545910-8C cm-2and 6.59 m A V-1, respectively. The device sensitivity is 9.36–9.42 m V g-1in the low frequency,and the first natural frequency is found to be 1230 Hz. The profile smoothness of the sensed signal is in 3 d B range up to1 k Hz.

关键词： mEmS micro-accelerometer Suspended gate FET Vertically movable gate FET VmGFET

Relative-Position Estimation Based on Loosely Coupled UWB–ImU Fusion for Wearable IoT Devices

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Computers, materials & Continua 2023年第4期75卷 1941-1961页

作者： A.S.m.Sharifuzzaman Sagar Taein Kim Soyoung Park hee Seh Lee Hyung Seok Kim Sejong University Seoul05006Korea Samsung Advanced Institute of Technology Suwon16678Korea

Relative positioning is one of the important techniques in collaborativerobotics, autonomous vehicles, and virtual/augmented reality (VR/AR)applications. Recently, ultra-wideband (UWB) has been utilized to calculaterelative position as it does not require a line of sight compared to a camerato calculate the range between two objects with centimeter-level ***, the single UWB range measurement cannot provide the relativeposition and attitude of any device in three dimensions (3D) because oflacking bearing information. In this paper, we have proposed a UWB-ImUfusion-based relative position system to provide accurate relative positionand attitude between wearable Internet of Things (IoT) devices in 3D. Weintroduce a distributed Euler angle antenna orientationwhich can be equippedwith the mobile structure to enable relative positioning. moving average andmin-max removing preprocessing filters are introduced to reduce the standarddeviation. The standard multilateration method is modified to calculate therelative position between mobile structures. We combine UWB and ImUmeasurements in a probabilistic framework that enables users to calculatethe relative position between two nodes with less error. We have carried outdifferent experiments to illustrate the advantages of fusing ImU and UWBranges for relative positioning systems. We have achieved a mean accuracy of0.31m for 3D relative positioning in indoor line of sight conditions.

关键词： Relative position UWB ImU trilateration IoT bayesian filter

Efficient electron extraction of SnO_(2) electron transport layer for lead halide perovskite solar cell

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npj Computational materials 2020年第1期6卷 836-843页

作者： Junu Kim kwang S.Kim Chang Woo myung Center for Superfunctional materials Department of PhysicsSchool of Natural ScienceUlsan National Institute of Science and Technology(UNIST)Ulsan 44919Korea Center for Superfunctional materials Department of ChemistrySchool of Natural ScienceUlsan National Institute of Science and Technology(UNIST)Ulsan 44919Korea

SnO_(2) electron transport layer(ETL)has been spotlighted with its excellent electron extraction and stability over TiO_(2) ETL for perovskite solar cells(PSCs),rapidly approaching the highest power conversion ***,how... 详细信息

关键词： ETL layer perovskite

microalgae Scenedesmus obliquus as renewable biomass feedstock for electricity generation in microbial fuel cells （mFCs）

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Frontiers of Environmental Science & Engineering 2014年第5期8卷 784-791页

作者： Sanath KONDAVEETI kwang Soon CHO Ramesh KAKARLA Booki mIN Department of Environmental Science and Engineering Kyung Hee University Gyeonggi-do 446-701 Republic of Korea

Renewable algae biomass, Scenedesmus obliquus, was used as substrate for generating electricity in two chamber microbial fuel cells （mFCs）. From polarization test, maximum power density with pretreated algal biomass was 102mW·m^2 （951mW·m^3） at current generation of 276mA·m^-2. The individual electrode potential as a function of current generation suggested that anodic oxidation process of algae substrate had limitation for high current generation in mFC. Total chemical oxygen demand （TCOD） reduction of 74% was obtained when initial TCOD concentration was 534mg · L^-1 for 150 h of operation. The main organic compounds of algae oriented biomass were lactate and acetate, which were mainly used for electricity generation. Other byproducts such as propionate and butyrate were formed at a negligible amount. Electrochemical Impedance Spectroscopy （EIS） analysis pinpointed the charge transfer resistance （112Ω ） of anode electrode, and the exchange current density of anode electrode was 1214 nA·cm^-2.

关键词： microbial fuel cell (mFC) algae bioelectricity substrate volatile fatty acid biomass COD removalefficiency

Inexpensive synthesis of a high-performance Fe3O4-SiO2-TiO2 photocatalyst： magnetic recovery and reuse

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Frontiers of Chemical Science and Engineering 2016年第3期10卷 405-416页

作者： Nadir Abbas Godlisten N. Shao Syed m. Imran muhammad S. Haider hee Taik Kim Department of Chemical Engineering Hanyang University Ansan-si Gyeonggi-do 426-791 Republic of Korea Department of Civil and Environmental Engineering Hanyang University Ansan-si Gyeonggi-do 426-791 Republic of Korea Department of Chemical Engineering University of Gujrat HH Campus Punjab Pakistan

A sol-gel technique has been developed for the synthesis of a magnetite-silica-titania （Fe3O4-SiO2-TiO2） tertiary nanocomposite with improved photocatalytic properties based on the use of inexpensive titania and silica precursors. The exceptional photocatalytic activity of the resulting materials was demonstrated by using them to photocatalyze the degradation of methylene blue solution. The best formulation achieved 98% methylene blue degradation. An interesting feature of the present work was the ability to magnetically separate and reuse the catalyst. The efficiency of the catalyst remained high during two reuses. The synthesized nanomaterials were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEm）, transmission electron micro- scopy （TEm）, Fourier transform infrared （FTIR） spectro- scopy, ultra-violet-visible spectroscopy, diffuse reflectance spectroscopy, and thermogravimetric analysis. XRD ana- lysis revealed the formation of multicrystalline systems of cubic magnetite and anatase titania crystals. SEm and TEm characterization revealed well-developed and homo- geneously dispersed particles of size less than 15 nm. FTIR spectra confirmed the chemical interaction of titania and silica. It was further noticed that the optical properties of the prepared materials were dependent on the relative contents of their constituent metal oxides.

关键词： sol-gel photocatalysis magnetic recovery,TiO2 Fe3O4 SiO2

On the Classification of Positive Quaternionic Khler manifolds with b_4=1

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Acta mathematica Sinica,English Series 2010年第5期26卷 875-884页

作者： Jin Hong KIm hee Kwon LEE Department of mathematical Sciences Korea Advanced Institute of Science and Technology Guseong-dong

Let m be a positive quaternionic Kahler manifold of dimension 4m. We already showed that if the symmetry rank is greater than or equal to [m/2] ＋ 2 and the fourth Betti number b4 is equal to one, then m is isometric to HPm. The goal of this paper is to report that we can improve the lower bound of the symmetry rank by one for higher even-dimensional positive quaternionic Kahler manifolds. Namely, it is shown in this paper that if the symmetry rank of m with b4（m） = 1 is greater than or equal to m/2 ＋ 1 for m ≥ 10, then m is isometric to HPm. One of the main strategies of this paper is to apply a more delicate argument of Frankel type to positive quaternionic Kahler manifolds with certain symmetry rank.

关键词： positive quaternionic Kahler symmetry