Investigation of natural convection heat transfer around a radial heat sink with a perforated ring

Li, Bin,Jeon, Sora,Byon, Chan Elsevier 2016 INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER - Vol.97 No.-

<P><B>Abstract</B></P> <P>Numerical studies were performed on natural convection heat transfer from radial heat sinks with perforated ring. The effects of perforation number (0–6), perforation diameter (0–3mm), and perforation length (1.5–6mm), and orientations angle (0–180°) on the thermal performance were investigated. The results show that radial heat sinks with a perforated ring obviously have better thermal performance than that with imperforated ring. Upwardly oriented radial heat sinks have the best thermal performance while sideward oriented radial heat sinks yield worst thermal performance. The geometric parameters of perforation is shown to affect the thermal performance of heat sink significantly at relatively higher heat transfer rate, especially for upward and sideward orientations. The thermal resistance of the radial heat sink with optimized perforated ring was shown to be less than that of imperforated ring by 17%, while reducing the mass of ring by up to 37%. This can be attributed to the unhindered natural convective flow through the perforation.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The radial heat sink with concentric ring is considered. </LI> <LI> The effect of the perforation and orientation on the thermal performance is investigated numerically. </LI> <LI> The optimized perforated heat sink can reduce the thermal resistance and mass significantly. </LI> <LI> The performance enhancement is shown to be attributed to the unhindered natural convective flow. </LI> </UL> </P>

Involvement of heme oxygenase-1 induction in the cytoprotective and immunomodulatory activities of 6,4′-dihydroxy-7-methoxyflavanone in murine hippocampal and microglia cells

Li, Bin,Lee, Dong-Sung,Jeong, Gil-Saeng,Kim, Youn-Chul Elsevier 2012 european journal of pharmacology Vol.674 No.2

<P>6,4'-Dihydroxy-7-methoxyflavanone (DMF), a biologically active compound, was isolated from the heartwood of Dalbergia odorifera T. Chen (Leguminosae). The present study proposed to examine the role of DMF as an anti-oxidative and anti-inflammatory home oxygenase-1 (HO-1) inducer in mouse hippocampal HT22 cells and BV2 microglia cells. The effect of DMF on cell viability was determined by MIT assay and the effects of DMF on pro-inflammatory enzymes and cytokines were analyzed by western blot and ELISA. Parameters such as DMF induced HO-1 protein immunocontents, HO activity and mitogen-activated protein kinases (MAPK) activation were also measured. DMF increased cellular resistance to oxidative injury caused by glutamate-induced cytotoxicity in HT22 cells, via JUN N-terminal kinase (JNK) pathway dependent HO-1 expression. Furthermore, DMF suppressed the lipopolysaccharide (LPS)-induced expression of pro-inflammatory enzymes and inflammatory mediators in BV2 microglia. DMF suppressed production of nitric oxide (NO), prostaglandin E2 (PGE(2)), tumor necrosis factor-alpha (INF-alpha) and interleukin-1 beta(IL-1 beta), through extracellular signal-regulated kinase (ERK) pathway dependent HO-1 expression. This study indicates that DMF effectively modulates the regulation of anti-oxidative and anti-inflammatory action, via up-regulation of HO-1 in HT22 cells and BV2 microglia. These results suggest that DMF possesses therapeutic potentials against neurodegenerative diseases that are induced by oxidative stress and neuroinflammation. (C) 2011 Elsevier B.V. All rights reserved.</P>

Involvement of Heme Oxygenase-1 Induction in the Cytoprotective and Immunomodulatory Activities of <i>Viola patrinii</i> in Murine Hippocampal and Microglia Cells

Li, Bin,Lee, Dong-Sung,Choi, Hyun-Gyu,Kim, Kyoung-Su,Jeong, Gil-Saeng,An, Ren Bo,Kim, Youn-Chul Hindawi Publishing Corporation 2012 Evidence-based Complementary and Alternative Medic Vol.2012 No.-

<P>A number of diseases that lead to injury of the central nervous system are caused by oxidative stress and inflammation in the brain. In this study, NNMBS275, consisting of the ethanol extract of <I>Viola patrinii</I>, showed potent antioxidative and anti-inflammatory activity in murine hippocampal HT22 cells and BV2 microglia. NNMBS275 increased cellular resistance to oxidative injury caused by glutamate-induced neurotoxicity and reactive oxygen species generation in HT22 cells. In addition, the anti-inflammatory effects of NNMBS275 were demonstrated by the suppression of proinflammatory mediators, including proinflammatory enzymes (inducible nitric oxide synthase and cyclooxygenase-2) and cytokines (tumor necrosis factor-<I><I>α</I></I> and interleukin-1<I><I>β</I></I>). Furthermore, we found that the neuroprotective and anti-inflammatory effects of NNMBS275 were linked to the upregulation of nuclear transcription factor-E2-related factor 2-dependent expression of heme oxygenase-1 in HT22 and BV2 cells. These results suggest that NNMBS275 possesses therapeutic potential against neurodegenerative diseases that are induced by oxidative stress and neuroinflammation.</P>

EFFICIENT CLUSTER IDENTIFICATION FOR MEASURED ULTRA-WIDEBAND CHANNEL IMPULSE RESPONSE IN VEHICLE CABIN

Li, Bin,Zhou, Zheng,Li, Dejian,Zhai, Shijun The Electromagnetics Academy (EMW Publishing) 2011 Electromagnetic waves Vol.117 No.-

Particle Swarm Optimization Based Noncoherent Detector for Ultra-Wideband Radio in Intensive Multipath Environments

Li, Bin,Zhou, Zheng,Zou, Weixia,Gao, Wanxin Hindawi Publishing Corporation 2011 EURASIP journal on advances in signal processing Vol.2011 No.1

<P>Given the dense multipath propagation in typical ultra-wideband channels, traditional coherent receivers may become computationally complex and impractical. Recently, noncoherent UWB architectures have been motivated with simple implementations. Nevertheless, the rudimentary statistical assumption and practical information uncertainty inevitably results in a hardly optimistic receiving performance. Inspired by the nature processes, in this paper we suggest a noncoherent UWB demodulator based on the particle swarm intelligence which can be realized in two steps. Firstly, a characteristic spectrum is developed from the received samples. From a novel pattern recognition perspective, four distinguishing features are extracted from this characteristic waveform to thoroughly reveal the discriminant properties of UWB multipath signals and channel noise. Subsequently, this established multidimensional feature space is compressed to a two-dimension plane by the optimal features combination technique, and UWB signal detection is consequently formulated to assign these pattern points into two classes at the minimum errors criterion. The optimal combination coefficients and the decision bound are then numerically derived by using the particle swarm optimization. Our biological noncoherent UWB receiver is independent of any explicit channel parameters, and hence is essentially robust to noise uncertainty. Numerical simulations further validate the advantages of our algorithm over the other noncoherent techniques.</P>

Probabilistic Analysis To Analyze Uncertainty Incorporating Copula Theory

Li Bin,Shahzad Muhammad,Munir Hafiz Mudassir,Nawaz Asif,Fahal Nabeel Abdelhadi Mohamed,Khan Muhammad Yousaf Ali,Ahmed Sheeraz 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.1

The emerging trend of distribution generation with existing power system network leads uncertainty factor. To handle this uncertainty, it is a provocation for the power system control, planning, and operation engineers. Although there are numerous techniques to model and evaluate these uncertainties, but in this paper the integration of Copula theory with Improved Latin-hypercube Sampling (ILHS) are incorporated for Probabilistic load Flow (PLF) evaluation. In probabilistic research approaches, the dominant interest is to achieve appropriate modelling of input random variables and reduce the computational burden. To address the said problem, Copula theory is applied to execute the modelling and interaction among input random variables of the active power system network. Considering the real discrete data, the ILHS is adopted. The load fl ow accessibility of the power system is carefully modeled by considering the dependence and uncertainty factors. Modifi ed IEEE 14-bus system is employed to analyze the effi ciency and performance of the proposed model using active power system network. Output power of two wind energy farms situated in New Jersey are obtained for accuracy comparison. The proposed technique shows the superiority in PLF evaluation.

Optimal Configuration and Economic Operation of Wind–Solar-Storage Complementary System for Agricultural Irrigation in Mountainous Areas

Li Bin,Zhao Jianing,Zhang Yangyang,Bai Xiaoqing 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.4

The disorderly use of electricity in agriculture is a serious source of the current electricity tension, and as distributed energy is expediently promoted, it is becoming increasingly notable that the source network and load are not well coordinated. Small pumped storage power station is established in this paper using irrigation facilities and mountain height differences. On the basis of satisfying the electricity demand for irrigation, the capacity of pumping units and generating sets is configured prudently with wind farms and photovoltaic power stations. In addition, fluctuation smoothing is factored into consideration, the spectrum analysis method is utilized to calibrate the installed capacity. We develop a wind-solar-pumped storage complementary day-ahead dispatching model with the objective of minimizing the grid connection cost by taking into account the uncertainty of wind power and photovoltaic output and combining the complementary characteristics. The proposed model and method were validated through simulation on four typical days for a microgrid system. The simulation results demonstrate that the system fully utilizes new energy sources and successfully addresses the issue of water and electricity consumption for agricultural irrigation in mountainous regions. This system also offers a valuable concept for achieving low carbon and environmental protection for agricultural electricity consumption.

First Report on Bacterial Heart Rot of Garlic Caused by Pseudomonas fluorescens in China

Li, Bin,Yu, Rong Rong,Yu, Shan Hong,Qiu, Wen,Fang, Yuan,Xie, Guan Lin The Korean Society of Plant Pathology 2009 Plant Pathology Journal Vol.25 No.1

An unreported disease of garlic was observed in commercial fields in Jiangsu province, China. The symptoms started as water soaked lesions at the base of the leaves. Later, water-soaked areas developed on stems and spread to the internal tissues, followed by yellowing and necrosis along leaf edges and soft rot of the stems. The causal organism isolated from symptomatic plants was identified as Pseudomonas fluorescens based on its biochemical and physiological characteristics and confirmed by the cellular fatty acid composition and Biolog data as well as 168 rRNA gene sequence analysis. The bacterial isolates caused similar symptoms when inoculated onto garlic plants. In addition, leek and shallot were susceptible to the P. fluorescens pathogen. However, the P. fluorescens pathogen failed to cause any symptoms when it was inoculated onto 15 other plants. This is the first report of a bacterial disease of garlic caused by P. fluorescens in China.

Analytical and mathematical simulation for nonlinear stability of scale-dependent magneto-electro-elastic system

Li, Bin,Xu, Xiaojia,Hu, Zhigang,Liu, Yuzuo,Qi, Menghui,Zheng, Zengquan Techno-Press 2021 Advances in nano research Vol.11 No.4

By using differential quadrature method (DQM), a numerical investigation was provided for nonlinear stability behavior of magneto-electro-elastic (MEE) cylindrical shells at microscale. It is assumed that the cylindrical shell has been subjected to compressive loads leading to buckling phenomena in geometrically nonlinear regime. The non-uniformity of strain field has been inserted in the formulation for considering the microscale effects. The material properties of the shell are considered to be inhomogeneous with graded distribution. After solving the governing equations using DQM, it is realized that if the nanoscale shell is subjected to electrical and magnetic fields, the post-buckling path may be changed with the value of electrical voltage and magnetic potential. Also, strain gradient effects have remarkable influence on post-buckling curves and critical voltages.

Reclassification of Xanthomonas Isolates Causing Bacterial Leaf Spot of Euphorbia pulcherrima

Li, Bin,Yu, Rongrong,Shi, Yu,Su, Ting,Wang, Fang,Ibrahim, Muhammad,Xie, Guanlin,Wang, Yanli,Sun, Guochang The Korean Society of Plant Pathology 2011 Plant Pathology Journal Vol.27 No.4

Bacterial leaf spot of Euphorbia pulcherrima has been reported in many countries. Characterization by polyphasic approaches indicated that the isolates from India, USA and New Zealand could be distinguished based on rep-PCR profiles and gyrB phylogenies, while the Chinese isolates should be ascribed to Xanthomonas axonopodis pv. poinsettiicola.