Structure and Performance Characteristics of Saturated Iron-core Superconducting Fault Current Limiter

Niu, Xiaoye,Chen, Zhili,Wang, Haizhen,Chen, Zhifu,Zhang, Lifeng,Niu, Guojun,Hong, Hui,Xin, Ying 대한전기학회 2014 The Journal of International Council on Electrical Vol.4 No.2

Superconducting fault current limiter (SFCL) is a kind of short-circuit current limiting device for power grid. It's a new application of superconducting technology on power equipments. Saturated Iron-core Superconducting fault current limiter (SISFCL) is one of many types of SFCL. It takes the advantage that no quenching occurs in superconducting wires during fault current limiting process. The immediately reacting and fast recovering are also its main characteristics. The structure and function of SISFCL is similar to that of traditional transformer and current limiting reactor respectively. Based on mature technologies on design and manufacture of iron core and windings of transformers, SISFCL could be made at the same voltage level as traditional transformers. But there are also significant differences between them. SISFCL will offer an effective solution to limit short-circuit current in future HV or EHV power systems because of its peculiar structures and properties. In this paper, we introduce the structure and characteristics of the SISFCL developed by Innopower. It may help readers to understand SISFCL and its enormous application value for power grids.

Synthesis and Properties of Self-healing Metallopolymers with 5-Vinyltetrazole Units and Zn(II)

Mifa Chen,Wenxiang Wang,Hou Chen,Liangjiu Bai,Zhongxin Xue,Donglei Wei,Huawei Yang,Yuzhong Niu 한국고분자학회 2019 Macromolecular Research Vol.27 No.1

The development of reversible and efficient self-healing materials symbolizes an emerging and challenging task in intelligent materials science. In this paper, a facile one-pot and two-step methodology was developed for the preparation of polyacrylonitrile-r-poly(butyl acrylate) (PAN-r-PnBA) and its subsequent modification. Zinc chloride (ZnCl2) was used as a catalyst to modify cyano groups and generate tetrazole groups of PAN-r-PnBA. Simultaneously, ZnCl2 effectively coordinates with the generated tetrazole group for highly self-healing performance. It was demonstrated that the metallopolymers (MPs) exhibited excellent self-healing properties at ambient temperature. The prepared tetrazole-based MPs can be used as a wide range of self-healing materials.

Moisture Content Measurement on Peanuts by using Time Domain Reflectometry

( Sheng Peng Niu ),( Tzu Hua Chen ),( Tse Min Chen ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.1

The Moisture content detection of non-homogeneous materials has always been a challenge, especially for agricultural products with time varied characteristics and specific compositions. For in-shelled peanuts, this research developed a system with which is able to detect moisture content promptly. Peanuts with high quality have to keep dry in all kinds of phases such as harvesting, storage, and processing. To prevent mold from breeding and the spread of aflatoxin, which will influence the value and quality severely, the moisture content of peanuts is a key parameter to be monitored and controlled. Therefore, a highly efficient device or mechanism will be required. However, there is still no any devices with enough accuracy and promptness to detect moisture content for peanuts yet. This study employed TDR (Time Domain Reflectometry) technology to challenge this mission. Comparing with the results of traditional IR measurement and standard oven, which helps to set up a calibration curve, this research validates the proposed method to detect the moisture content of in-shell peanut finally.

Transplantation of Gelatin Microspheres Loaded with Wharton's Jelly Derived Mesenchymal Stem Cells Facilitates Cartilage Repair in Mice

Chen Xiaolin,Huang Sunxing,Niu Yongxia,Luo Mingxun,Liu Haiying,Jiao Yiren,Huang Junjiu 한국조직공학과 재생의학회 2024 조직공학과 재생의학 Vol.21 No.1

Background: Knee osteoarthritis (KOA) is a prevalent chronic joint disease caused by various factors. Mesenchymal stem cells (MSCs) therapy is an increasingly promising therapeutic option for osteoarthritis. However, the chronic inflammation of knee joint can severely impede the therapeutic effects of transplanted cells. Gelatin microspheres (GMs) are degradable biomaterial that have various porosities for cell adhesion and cell–cell interaction. Excellent elasticity and deformability of GMs make it an excellent injectable vehicle for cell delivery. Methods: We created Wharton’s jelly derived mesenchymal stem cells (WJMSCs)-GMs complexes and assessed the effects of GMs on cell activity, proliferation and chondrogenesis. Then, WJMSCs loaded in GMs were transplanted in the joint of osteoarthritis mice. After four weeks, joint tissue was collected for histological analysis. Overexpressing-luciferase WJMSCs were performed to explore cell retention in mice. Results: In vitro experiments demonstrated that WJMSCs loaded with GMs maintained cell viability and proliferative potential. Moreover, GMs enhanced the chondrogenesis differentiation of WJMSCs while alleviated cell hypertrophy. In KOA mice model, transplantation of WJMSCs-GMs complexes promoted cartilage regeneration and cartilage matrix formation, contributing to the treatment of KOA. Compared with other groups, in WJMSCs+GMs group, there were fewer cartilage defects and with a more integrated tibia structure. Tracking results of stable-overexpressing luciferase WJMSCs demonstrated that GMs significantly extended the retention time of WJMSCs in knee joint cavity. Conclusion: Our results indicated that GMs facilitate WJMSCs mediated knee osteoarthritis healing in mice by promoting cartilage regeneration and prolonging cell retention. It might potentially provide an optimal strategy for the biomaterial-stem cell based therapy for knee osteoarthritis. Background: Knee osteoarthritis (KOA) is a prevalent chronic joint disease caused by various factors. Mesenchymal stem cells (MSCs) therapy is an increasingly promising therapeutic option for osteoarthritis. However, the chronic inflammation of knee joint can severely impede the therapeutic effects of transplanted cells. Gelatin microspheres (GMs) are degradable biomaterial that have various porosities for cell adhesion and cell–cell interaction. Excellent elasticity and deformability of GMs make it an excellent injectable vehicle for cell delivery. Methods: We created Wharton’s jelly derived mesenchymal stem cells (WJMSCs)-GMs complexes and assessed the effects of GMs on cell activity, proliferation and chondrogenesis. Then, WJMSCs loaded in GMs were transplanted in the joint of osteoarthritis mice. After four weeks, joint tissue was collected for histological analysis. Overexpressing-luciferase WJMSCs were performed to explore cell retention in mice. Results: In vitro experiments demonstrated that WJMSCs loaded with GMs maintained cell viability and proliferative potential. Moreover, GMs enhanced the chondrogenesis differentiation of WJMSCs while alleviated cell hypertrophy. In KOA mice model, transplantation of WJMSCs-GMs complexes promoted cartilage regeneration and cartilage matrix formation, contributing to the treatment of KOA. Compared with other groups, in WJMSCs+GMs group, there were fewer cartilage defects and with a more integrated tibia structure. Tracking results of stable-overexpressing luciferase WJMSCs demonstrated that GMs significantly extended the retention time of WJMSCs in knee joint cavity. Conclusion: Our results indicated that GMs facilitate WJMSCs mediated knee osteoarthritis healing in mice by promoting cartilage regeneration and prolonging cell retention. It might potentially provide an optimal strategy for the biomaterial-stem cell based therapy for knee osteoarthritis.

Evaluation of the different filter media in vertical flow stormwater wetland

Chen, Yaoping,Cheng, Jing,Niu, Siping,Kim, Youngchul Informa UK (Taylor Francis) 2013 Desalination and water treatment Vol.51 No.19

Sensitivity analysis of circumferential transducer array with T(0,1) mode of pipes

Niu, Xudong,Marques, Hugo R.,Chen, Hua-Peng Techno-Press 2018 Smart Structures and Systems, An International Jou Vol.21 No.6

Guided wave testing is a reliable and safe method for pipeline inspection. In general, guided wave testing employs a circumferential array of piezoelectric transducers to clamp on the pipe circumference. The sensitivity of the operation depends on many factors, including transducer distribution across the circumferential array. This paper presents the sensitivity analysis of transducer array for the circumferential characteristics of guided waves in a pipe using finite element modelling and experimental studies. Various cases are investigated for the outputs of guided waves in the numerical simulations, including the number of transducers per array, transducer excitation variability and variations in transducer spacing. The effect of the dimensions of simulated notches in the pipe is also investigated for different arrangements of the transducer array. The results from the finite element numerical simulations are then compared with the related experimental results. Results show that the numerical outputs agree well with the experimental data, and the guided wave mode T(0,1) presents high sensitivity to the notch size in the circumferential direction, but low sensitivity to the notch size in the axial direction.

Multi-regional Anti-jamming Communication Scheme Based on Transfer Learning and Q Learning

( Chen Han ),( Yingtao Niu ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.7

The smart jammer launches jamming attacks which degrade the transmission reliability. In this paper, smart jamming attacks based on the communication probability over different channels is considered, and an anti-jamming Q learning algorithm (AQLA) is developed to obtain anti-jamming knowledge for the local region. To accelerate the learning process across multiple regions, a multi-regional intelligent anti-jamming learning algorithm (MIALA) which utilizes transferred knowledge from neighboring regions is proposed. The MIALA algorithm is evaluated through simulations, and the results show that the it is capable of learning the jamming rules and effectively speed up the learning rate of the whole communication region when the jamming rules are similar in the neighboring regions.

Cytokine-Mediated Disruption of Lymphocyte Trafficking, Hemopoiesis, and Induction of Lymphopenia, Anemia, and Thrombocytopenia in Anti-CD137-Treated Mice

Niu, L.,Strahotin, S.,Hewes, B.,Zhang, B.,Zhang, Y.,Archer, D.,Spencer, T.,Dillehay, D.,Kwon, B.,Chen, L. American Association of Immunologists 2007 Journal of Immunology Vol.178 No.7

Implementation and verification of a four-probe motion error measurement system for a large-scale roll lathe used in hybrid manufacturing

Chen, Yuan-Liu,Niu, Zengyuan,Matsuura, Daiki,Lee, Jung Chul,Shimizu, Yuki,Gao, Wei,Oh, Jeong Seok,Park, Chun Hong IOP Pub 2017 Measurement science & technology Vol.28 No.10

<P>In this paper, a four-probe measurement system is implemented and verified for the carriage slide motion error measurement of a large-scale roll lathe used in hybrid manufacturing where a laser machining probe and a diamond cutting tool are placed on two sides of a roll workpiece for manufacturing. The motion error of the carriage slide of the roll lathe is composed of two straightness motion error components and two parallelism motion error components in the vertical and horizontal planes. Four displacement measurement probes, which are mounted on the carriage slide with respect to four opposing sides of the roll workpiece, are employed for the measurement. Firstly, based on the reversal technique, the four probes are moved by the carriage slide to scan the roll workpiece before and after a 180-degree rotation of the roll workpiece. Taking into consideration the fact that the machining accuracy of the lathe is influenced by not only the carriage slide motion error but also the gravity deformation of the large-scale roll workpiece due to its heavy weight, the vertical motion error is thus characterized relating to the deformed axis of the roll workpiece. The horizontal straightness motion error can also be synchronously obtained based on the reversal technique. In addition, based on an error separation algorithm, the vertical and horizontal parallelism motion error components are identified by scanning the rotating roll workpiece at the start and the end positions of the carriage slide, respectively. The feasibility and reliability of the proposed motion error measurement system are demonstrated by the experimental results and the measurement uncertainty analysis.</P>

An empirical model for amplitude prediction on VIV-galloping instability of rectangular cylinders

Niu, Huawei,Zhou, Shuai,Chen, Zhengqing,Hua, Xugang Techno-Press 2015 Wind and Structures, An International Journal (WAS Vol.21 No.1

Aerodynamic forces of vortex-induced vibration and galloping are going to be coupled when their onset velocities are close to each other, which will induce the cross-wind amplitudes of the structures increased continuously with ever-increasing wind velocities. The main purpose of the present work is going to propose an empirical formula to predict the response amplitude of VIV-galloping interaction. Firstly, two typical mathematical models for the coupled oscillations, i.e., Tamura & Shimada model and Parkinson & Corless model are comparatively summarized. Then, the key parameter affecting response amplitude is determined through comparative numerical simulations with Tamura & Shimada model. For rectangular cylinders with the side ratio from 0.5 to 2.5, which are actually prone to develop the VIV and galloping induced interaction responses, an empirical amplitude prediction formula is proposed after regression analysis on comprehensively collected experimental data with the predetermined key parameter.