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A Hybrid of Smartphone Camera and Basestation Wide-area Indoor Positioning Method

  • Jiao, Jichao;Deng, Zhongliang;Xu, Lianming;Li, Fei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.2
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    • pp.723-743
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    • 2016
  • Indoor positioning is considered an enabler for a variety of applications, the demand for an indoor positioning service has also been accelerated. That is because that people spend most of their time indoor environment. Meanwhile, the smartphone integrated powerful camera is an efficient platform for navigation and positioning. However, for high accuracy indoor positioning by using a smartphone, there are two constraints that includes: (1) limited computational and memory resources of smartphone; (2) users' moving in large buildings. To address those issues, this paper uses the TC-OFDM for calculating the coarse positioning information includes horizontal and altitude information for assisting smartphone camera-based positioning. Moreover, a unified representation model of image features under variety of scenarios whose name is FAST-SURF is established for computing the fine location. Finally, an optimization marginalized particle filter is proposed for fusing the positioning information from TC-OFDM and images. The experimental result shows that the wide location detection accuracy is 0.823 m (1σ) at horizontal and 0.5 m at vertical. Comparing to the WiFi-based and ibeacon-based positioning methods, our method is powerful while being easy to be deployed and optimized.

Semi-supervised Multi-view Manifold Discriminant Intact Space Learning

  • Han, Lu;Wu, Fei;Jing, Xiao-Yuan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.9
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    • pp.4317-4335
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    • 2018
  • Semi-supervised multi-view latent space learning is gaining considerable popularity recently in many machine learning applications due to the high cost and difficulty to obtain the large amount of label information of data. Although some semi-supervised multi-view latent space learning methods have been presented, there is still much space for improvement: 1) How to learn latent discriminant intact feature representations by employing data of multiple views; 2) How to exploit the manifold structure of both labeled and unlabeled point in the learned latent intact space effectively. To address the above issues, we propose an approach called semi-supervised multi-view manifold discriminant intact space learning ($SM^2DIS$) for image classification in this paper. $SM^2DIS$ aims to seek a manifold discriminant intact space for data of different views by making use of both the discriminant information of labeled data and the manifold structure of both labeled and unlabeled data. Experimental results on MNIST, COIL-20, Multi-PIE, and Caltech-101 databases demonstrate the effectiveness and robustness of our proposed approach.

Sensitivity Enhancement of Polyaniline Sensor to Volatile Organic Compounds (휘발성유기화합물가스에 대한 폴리아닐린 센서의 감도 향상)

  • Yu, Joon-Boo;Liu, Fei;Lim, Jeong-Ok;Byun, Hyung-Gi;Huh, Jeung-Soo
    • Korean Journal of Materials Research
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    • v.17 no.8
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    • pp.433-436
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    • 2007
  • Nano-structured polyaniline have been synthesized by interfacial polymerization method at room temperature. An aqueous solution of aniline in chloroform and another solution of ammonium peroxydisulfate in doping acid were prepared at different times terminated with methanol at room temperature. SEM, UV-vis were used to characterize the polyaniline with regard to their morphology and structure. The diameter and length of polyaniline can be controlled by the reaction time. Nano-structured polyaniline were found to have superior sensitivity for volatile organic compounds(VOCs). As the reaction time to increase from 30minute to 2hours the sensitivity were decreased to VOCs vapors. The sensitivity of Nano-structured polyaniline sensor appeared to VOCs better than the sensitivity of chemical synthesis sensors. The sensitivity of Nano-structured polyaniline sensor improved benzene vapors.

Monte Carlo shielding evaluation of a CSNS Multi-Physics instrument

  • Liang, Tairan;Shen, Fei;Yin, Wen;Xu, Juping;Yu, Quanzhi;Liang, Tianjiao
    • Nuclear Engineering and Technology
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    • v.51 no.8
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    • pp.1998-2004
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    • 2019
  • The Multi-Physics (MP) instrument is one of 20 neutron spectrometers planned in the China Spallation Neutron Source (CSNS). This paper presents a shielding calculation for the MP instrument using Monte Carlo codes MCNPX and FLUKA. First, the neutrons that escape from the CSNS decoupled water moderator and are delivered to the beam line of the MP instrument are calculated to use as the source term of the shielding calculation. Then, to validate the calculation method based on multiple variance reduction techniques, a cross check between MCNPX and FLUKA codes is performed by comparing the calculation results of the dose rate distribution on a simplified beam line model. Finally, a complete geometry model of the MP instrument is set up, and the primary parameters for the shielding design are obtained according to the calculated dose rate map considering different worst-case scenarios.

Efficient and Selective Construction of Pyrrolo[3,2-d]pyrimidine Derivatives

  • He, Ping;Wu, Jing;Hu, Yang-Gen;Li, Zai-Fang;Hou, Qiu-Fei;Wang, Yan-Ling;Zhao, Kun;Zhang, Erli
    • Bulletin of the Korean Chemical Society
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    • v.35 no.2
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    • pp.617-621
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    • 2014
  • An efficient and selective method for the synthesis of ethyl 2-amino/aryloxy-3-aryl-4-oxo-5-phenyl-4,5-dihydro-3H-pyrrolo[3,2-d]pyrimidine-7-carboxylate derivatives has been developed. The main process involved the reaction of diethyl 1-phenyl-3-((triphenylphosphoranylidene)amino)-1H-pyrrole-2,4-dicarboxylate and aromatic isocyanates, followed by addition of amines/phenols in the presence of catalytic amount of sodium ethoxide or solid potassium carbonate.

P-Selectin-mediated Acute Inflammation Can Be Blocked by Chemically Modified Heparin, RO-Heparin

  • Gao, Yanguang;Li, Na;Fei, Rui;Chen, Zhihong;Zheng, Sheng;Zeng, Xianlu
    • Molecules and Cells
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    • v.19 no.3
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    • pp.350-355
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    • 2005
  • Selectins are carbohydrate-binding cell adhesion molecules that play a major role in the initiation of inflammatory responses. Heparin can bind to P-selectin, and its anti-inflammatory property is mainly due to inhibition of P-selectin. However, the strong anticoagulant activity of heparin limits its clinical use. We prepared periodate-oxidized, borohydride-reduced heparin (RO-heparin) by chemical modification and tested its anticoagulant and anti-inflammatory activities. Activated partial thromboplastin time (aPTT) assays showed that, compared with heparin, RO-heparin had greatly reduced anticoagulant activity. Intravenous administration of this compound led to reduction in the peritoneal infiltration of neutrophils in a mouse acute inflammation model. In vitro cell adhesion experiments demonstrated that the effect of RO-heparin on inflammatory responses was mainly due to inhibiting the interaction of P-selectin with its ligands. These results indicate that RO-heparin may be a safer treatment for inflammation than heparin, especially when selectin is targeted.

Improvement on the Laminated Busbar of NPC Three-Level Inverters based on a Supersymmetric Mirror Circulation 3D Cubical Thermal Model

  • He, Feng-You;Xu, Shi-Zhou;Geng, Cheng-Fei
    • Journal of Power Electronics
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    • v.16 no.6
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    • pp.2085-2098
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    • 2016
  • Laminated busbars with a low stray inductance are widely used in NPC three-level inverters, even though some of them have poor performances in heat equilibrium and overvoltage suppression. Therefore, a theoretical method is in need to establish an accurate mathematical model of laminated busbars and to calculate the impedance and stray inductance of each commutation loop to improve the heat equilibrium and overvoltage suppression performance. Firstly, an equivalent circuit of a NPC three-level inverter laminated busbar was built with an analysis of the commutation processes. Secondly, on the basis of a 3D (three dimensional) cubical thermal model and mirror circulation theory, a supersymmetric mirror circulation 3D cubical thermal model was built. Based on this, the laminated busbar was decomposed in 3D space to calculate the equivalent resistance and stray inductance in each commutation loop. Finally, the model and analysis results were put into a busbar design, simulation and experiments, whose results demonstrate the accuracy and feasibility of the proposed method.

A Study on the Teaching Method of Korean Pronunciation for the Chinese Learners (중국인 초급 학습자의 한국어 발음 교육 연구 - 자음과 모음을 중심으로 -)

  • Jiang, Fei
    • Korean Educational Research Journal
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    • v.40 no.2
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    • pp.35-56
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    • 2019
  • This study is concentrated to search for the effective teaching method of Korean pronunciation as one of Korean language teaching for the chinese. Pronunciation is the most basic factor in the use of language. pronunciation is the basic factor for learners to judge the fluency and accuracy of the target language in the process of communication. but people usually learn the second- language when they are adults, who are surely influenced by mother language. Therefore, it is the main purpose of this thesis to seek vocal sound system and phonological phenomena in Korean and Chinese and figure out the common and difference of these two languages through contrastive analysis.

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Recent Developments in Piezoelectric Crystals

  • Zhang, Shujun;Li, Fei;Yu, Fapeng;Jiang, Xiaoning;Lee, Ho-Yong;Luo, Jun;Shrout, T.R.
    • Journal of the Korean Ceramic Society
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    • v.55 no.5
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    • pp.419-439
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    • 2018
  • Piezoelectric materials are essential parts of the electronics and electrical equipment used for consumer and industrial applications, such as ultrasonic piezoelectric transducers, sensors, actuators, transformers, and resonators. In this review, the development of piezoelectric materials and the figures of merit for various electromechanical applications are surveyed, focusing on piezoelectric crystals, i.e., the high-performance relaxor-$PbTiO_3$-based perovskite ferroelectric crystals and nonferroelectric high-temperature piezoelectric crystals. The uniqueness of these crystals is discussed with respect to different usages. Finally, the existing challenges and perspective for the piezoelectric crystals are discussed, with an emphasis on the temperature-dependent properties, from cryogenic temperatures up to the ultrahigh-temperature usage range.

Active Distribution System Planning Considering Battery Swapping Station for Low-carbon Objective using Immune Binary Firefly Algorithm

  • Shi, Ji-Ying;Li, Ya-Jing;Xue, Fei;Ling, Le-Tao;Liu, Wen-An;Yuan, Da-Ling;Yang, Ting
    • Journal of Electrical Engineering and Technology
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    • v.13 no.2
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    • pp.580-590
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    • 2018
  • Active distribution system (ADS) considering distributed generation (DG) and electric vehicle (EV) is an effective way to cut carbon emission and improve system benefits. ADS is an evolving, complex and uncertain system, thus comprehensive model and effective optimization algorithms are needed. Battery swapping station (BSS) for EV service is an essential type of flexible load (FL). This paper establishes ADS planning model considering BSS firstly for the minimization of total cost including feeder investment, operation and maintenance, net loss and carbon tax. Meanwhile, immune binary firefly algorithm (IBFA) is proposed to optimize ADS planning. Firefly algorithm (FA) is a novel intelligent algorithm with simple structure and good convergence. By involving biological immune system into FA, IBFA adjusts antibody population scale to increase diversity and global search capability. To validate proposed algorithm, IBFA is compared with particle swarm optimization (PSO) algorithm on IEEE 39-bus system. The results prove that IBFA performs better than PSO in global search and convergence in ADS planning.