Analyses Leakage Magnetic Field of DC biased transformer with Magnetic Circuit Method

Chen Yinghui,Lu Tiebing,Li Lin,Zhao zhibing,Cheng zhiguang,Wangjianmin 한국자기학회 2008 한국자기학회 학술연구발표회 논문개요집 Vol.- No.-

Preparation and Properties of Water-Resistant Antibacterial Curcumin/Silver Composite Nanofiber

Meiping Chen,Chao Ma,Change Zhou,Zhiguang Li,Rong Li 한국섬유공학회 2023 Fibers and polymers Vol.24 No.11

The water-resistant antibacterial PVA nanofibers containing curcumin (Cur) and silver nanoparticles (AgNPs) were prepared by electrospinning, and the AgNps were prepared by in situ reduction in the spinning solution. The prepared PVA nanofibers were measured by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectrophotometer (FT-IR). The breathable, hygroscopic, antibacterial, anti-inflammatory, and antioxidants functions of the prepared nanofibers were evaluated. The results indicated that the prepared nanofiber membrane has high swelling rate, moisture permeability, good mechanical properties, good biocompatibility, anti-inflammatory, antioxidant, and bacteriostatic activities with no cytotoxicity. Curcumin and AgNPs in the prepared nanofiber have effect on antibacterial activity and wound healing. The functionalized silver nanoparticles developed have effective activities against both Gram-negative bacteria and Gram-positive bacteria. In short, Cur/AgNPs composite nanofibers can be used as a potential medical dressing with antibacterial, anti-inflammatory, and antioxidant properties.

CAWR: Buffer Replacement with Channel-Aware Write Reordering Mechanism for SSDs

Ronghui Wang,Zhiguang Chen,Nong Xiao,Minxuan Zhang,Weihua Dong 한국전자통신연구원 2015 ETRI Journal Vol.37 No.1

A typical solid-state drive contains several independent channels that can be operated in parallel. To exploit this channel-level parallelism, a variety of works proposed to split consecutive write sequences into small segments and schedule them to different channels. This scheme exploits the parallelism but breaks the spatial locality of write traffic; thus, it is able to significantly degrade the efficiency of garbage collection. This paper proposes a channel-aware write reordering (CAWR) mechanism to schedule write requests to different channels more intelligently. The novel mechanism encapsulates correlated pages into a cluster beforehand. All pages belonging to a cluster are scheduled to the same channels to exploit spatial locality, while different clusters are scheduled to different channels to exploit the parallelism. As CAWR covers both garbage collection and I/O performance, it outperforms existing schemes significantly. Trace-driven simulation results demonstrate that the CAWR mechanism reduces the average response time by 26% on average and decreases the valid page copies by 10% on average, while achieving a similar hit ratio to that of existing mechanisms.

Impact test of a centrifugal pump used in nuclear power plant under aircraft crash scenario

Huang, Tao,Chen, Mengmeng,Li, Zhongcheng,Dong, Zhanfa,Zhang, Tiejian,Zhou, Zhiguang Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.6

Resisting an accidental impact of large commercial aircrafts is an important aspect of advanced nuclear power plant (NPP) design. Especially after the 9·11 event, some regulations were enacted, which required the design of NPPs should consider the accidental impact of large commercial aircrafts. Normal working of equipment is important for stopping reactor under an impact when an NPP is in operation. However, there is a lack of reliable analysis and research on the impact test of nuclear prototype equipment. Therefore, in order to study the response of the equipment under high acceleration impact, a centrifugal pump is selected as the research object to perform the impact test. A horizontal half-sinusoidal pulse wave was applied to the working pump. The test results show that the horizontal response of the motor and flange is greater compared to other parts, as well as the vertical response of the coupling. The stress response of the pump body support and motor support is high, hence these parts should be considered in the design of the pump. Finally, combined with the damage and stress evaluation results of the pump under different amplitudes, the ultimate impact acceleration that the pump can withstand is given.

Fine-Grained Access Control for Cloud Data Sharing by Secure and Efficient Attribute-Revocable Ciphertext-Policy Attribute-Based Encryption

Nyamsuren Vaanchig,Wei Chen,Zhiguang Qin 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.10

Nowadays, more and more users outsource their data to third party cloud storage servers for the purpose of sharing, so cloud data sharing becomes one of the popular services offered by cloud service providers. However, the third party storage servers in cloud data sharing systems, which are not fully trusted by data owners, make access control to the shared data a challenging issue. Although Ciphertext-Policy Attribute-Based Encryption (CP-ABE) is an emerging cryptographic solution for this issue, dealing with dynamic changes to users' access privileges (attribute revocation) in its practical applications as cloud data sharing systems is a real challenge. To overcome this challenge, we propose a fine-grained access control scheme for cloud data sharing systems by designing secure and efficient attribute-revocable CP-ABE scheme. Our scheme only allows non-revoked users in the attribute group to update their secret key by themselves using their unique key-update keys and the ciphertexts are updated by minimally trusted cloud server using a ciphertext-update key. Compared with the existing access controls achieved by attribute-revocable CP-ABE schemes, our proposed access control scheme reduces the trust degree of the cloud server in the attribute revocation mechanism. Furthermore, the analysis indicates that our access control scheme is more secure and efficient to apply to practical scenarios.

Fabrication of Stable Fluorine-Free Hydrophobic Cotton Fabrics with Prominent Antibacterial Property

Fengyi Qian,Meiping Chen,Zhiguang Li,Change Zhou,Rong Li,Xuehong Ren 한국섬유공학회 2023 Fibers and polymers Vol.24 No.11

Multifunctional cotton fabrics with antibacterial property and hydrophobicity were prepared using surface modification. Cotton fabrics were treated with the coating solution containing N-halamine compound poly[5,5-dimethyl-3-(3’-triethoxysilylpropyl) hydantoin] (PSPH) and TiO2 nanoparticles, followed by treated with polydimethylsiloxane (PDMS) to reduce the surface energy of cotton fabrics. The prepared cotton fabrics were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier transform infrared (FT-IR) spectra, X-ray photoelectron spectroscopy (XPS), and X-ray diffractometry (XRD). After chlorination, the prepared cotton fabrics exhibited excellent hydrophobicity with contact angle of 143°. The antibacterial results demonstrated that the prepared cotton fabrics had excellent antibacterial activity and could completely inactivate 4.54 cfu/sample of S.aureus and 4.92 cfu/sample of E. coli O157:H7 within 30 min of contact. The treated cotton fabrics also possessed robust stability under washing, UV light irradiation, and abrasion. Moreover, the breaking strength and air permeability of cotton fabric could maintain to the required values for practical application after treatment.

The Antibacterial and Hydrophobic Cotton Fabrics Constructed by Multifunctional Polysiloxane and TiO2 Nanoparticles

Fengyi Qian,Meiping Chen,Change Zhou,Zhiguang Li,Rong Li,Xuehong Ren 한국섬유공학회 2023 Fibers and polymers Vol.24 No.2

Multifunctional polysiloxane was synthesized by introducing N-halamine compound precursor and stearyl methacrylateinto polyhydromethylsiloxane, and characterized by Fourier transform infrared (FT-IR) and 1H nuclear magnetic resonance(NMR). Cotton fabrics with antibacterial and hydrophobic properties were prepared via a simple one-pot method with thesynthesized polysiloxane and rutile TiO2nanoparticles. The prepared cotton fabrics was characterized by scanning electronmicroscopy (SEM), FT-IR, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The results demonstratedthat prepared cotton fabrics could inactivate 3.9 × 106cfu/sample of S. aureus and 4.8 × 106cfu/sample of E. coli O157:H7within 30 min of contact time, and the water contact angle of the treated fabrics was 133°. The prepared cotton fabrics alsoexhibited excellent stability against 50 abrasion cycles. After 50 washing cycles, 72% of the chlorine content on preparedcotton fabrics could be recovered after rechlorination. And the antibacterial hydrophobic cotton fabrics loaded with TiO2possessed higher UV stability than cotton fabrics only treated with PTSAMS-Cl. Furthermore, the breaking strength ofantibacterial hydrophobic cotton fabrics was decreased while the wrinkle resistance was improved.

Overexpression of miR-155-5p Inhibits the Proliferation and Migration of IL-13-Induced Human Bronchial Smooth Muscle Cells by Suppressing TGF-β-Activated Kinase 1/MAP3K7-Binding Protein 2

Yujia Shi,Xingli Fu,Qi Cao,Zhengdao Mao,Yi Chen,Yun Sun,Zhiguang Liu,Qian Zhang 대한천식알레르기학회 2018 Allergy, Asthma & Immunology Research Vol.10 No.3

Purpose: Molecular mechanisms leading to asthma is still ill-defined. Though the function of microRNAs (miRNAs) in asthma was previously reported, the involvement of miR-155 in important features of this disease remains unknown. The present study was designed to uncover the probable involvement of miR-155-5p in the proliferation and migration of IL-13-induced human bronchial smooth muscle cells (BSMCs) and the intrinsic regulatory mechanism. Methods: The effects of different concentrations of IL-13 on the proliferation and migration of BSMCs as well as the expression of miR-155-5p and its predicted target transforming growth factor (TGF)-β-activated kinase 1/MAP3K7-binding protein 2 (TAB2) were investigated. The effects of miR-155-5p on the proliferation and migration of interleukin (IL)-13-induced BSMCs was determined in vitro using BSMCs transfected with miR-155 mimic/inhibitor and induced by a high concentration of IL-13. The quantitative real-time polymerase chain reaction (qRT-PCR) was employed for determining the expression of miR-155-5p and TAB2. Western blotting was applied to analyze the expression of TAB2 at the protein level. Cell proliferation and migration were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Transwell assays, respectively. Results: The proliferation and migration of BSMCs were dose-dependently increased with IL-13 treatment. Contrariwise, IL-13 dose-dependently inhibited the expression of miR-155-5p in BSMCs. Mechanistic studies showed that inhibition of miR-155-5p further promoted the stimulatory effects of IL-13, whereas overexpression of miR-155 significantly inhibited these effects. In silico studies and luciferase reporter assays indicated that TAB2 was a negatively regulated miR-155-5p target. Conclusions: These results suggested that miR-155-5p-inhibit the IL-13-induced proliferation and migration of BSMCs by targeting TAB2 and that the IL-13/miR-155/TAB2 pathway could serve as a therapeutic target for pulmonary diseases, especially asthma.