Remaining Useful Life Prediction of Lithium-Ion Batteries Based on Spherical Cubature Particle Filter

Dong Wang,Fangfang Yang,Kwok-Leung Tsui,Qiang Zhou,Suk Joo Bae Institute of Electrical and Electronics Engineers 2016 IEEE transactions on instrumentation and measureme Vol.65 No.6

<P>Lithium-ion batteries are critical components to provide power sources for commercial products. To ensure a high reliability of lithium-ion batteries, prognostic actions for lithium-ion batteries should be prepared. In this paper, a prognostic method is proposed to predict the remaining useful life (RUL) of lithium-ion batteries. A state-space model for the lithium-ion battery capacity is first constructed to assess capacity degradation. Then, a spherical cubature particle filter (SCPF) is introduced to solve the state-space model. The major idea of the SCPF is to adapt a spherical cubature integration-based Kalman filter to provide an importance function of a standard particle filter (PF). Once the state-space model is determined, the extrapolations of the state-space model to a specified failure threshold are performed to infer the RUL of the lithium-ion batteries. Degradation data of 26 lithium-ion battery capacities were analyzed to validate the effectiveness of the proposed prognostic method. The analytical results show that the proposed prognostic method is more effective in the prediction of RUL of lithium-ion batteries, compared with an existing PF-based prognostic method.</P>

Compact microstrip feed dual band monopole antenna for UWB and bluetooth applications

Jiang, FangFang,Park, Dong-Kook Korean Society of Marine Engineers 2017 한국마린엔지니어링학회지 Vol.41 No.10

This paper presents a small printed monopole antenna for ultra-wide band (UWB) (3.1~10.6 GHz) and Bluetooth (2.4~2.48 GHz). The proposed antenna consists of a small U-shaped UWB radiating patch and a lollipop-shaped Bluetooth radiating patch. This antenna is fed by a microstrip line and built by RF-4 dielectric substrate having a thickness of 1.6 mm. The size of the designed antenna is $15{\times}26mm^2$, which is significantly smaller than the previous similar antenna. The simulated and measured results show that the proposed antenna achieves a broad operating bandwidth of 2.95~11.5 GHz for UWB application, and 2.38~2.52 GHz for Bluetooth application. The designed antenna has an omnidirectional radiation patterns and stable gain.

Biocompatibility of Nanoscale Hydroxyapatite-embedded Chitosan Films

Sun, Fangfang,Koh, Kwangnak,Ryu, Su-Chak,Han, Dong-Wook,Lee, Jaebeom Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.12

In order to improve the bioactivity and mechanical properties of hydroxyapatite (HAp), chitosan (Chi) was in situ combined into HAp to fabricate a composite scaffold by a sublimation-assisted compression method. A highly porous film with sufficient mechanical strength was prepared and the bioactivity was investigated by examining the apatite formed on the scaffolds incubated in simulated body fluid. In addition, the cytotoxicity of the HAp/Chi composite was studied by evaluating the viability of murine fibroblasts (L-929 cells) exposed to diluted extracts of the composite films. The apatite layer was assessed using scanning electronic microscopy, inductively coupled plasma-optical emission spectrometry and weight measurement. Composite analysis showed that a layer of micro-sized, needle-like crystals was formed on the surface of the composite film. Additionally, the WST-8 assay after L-929 cells were exposed to diluted extracts of the composite indicated that the HAp/Chi scaffold has good in vitro cytocompatibility. The results indicated that HAp/Chi composites with porous structure are promising scaffolding materials for bone-patch engineering because their porous morphology can provide an environment conductive to attachment and growth of osteoblasts and osteogenic cells.

Extracellular signal-regulated kinase 5 increases radioresistance of lung cancer cells by enhancing the DNA damage response

Weiwei Jiang,Guanghui Jin,Fangfang Cai,Xiao Chen,Nini Cao,Xiangyu Zhang,Jia Liu,Fei Chen,Feng Wang,Wei Dong,Hongqin Zhuang,Zichun Hua 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

Radiotherapy is a frequent mode of cancer treatment, although the development of radioresistance limits its effectiveness. Extensive investigations indicate the diversity of the mechanisms underlying radioresistance. Here, we aimed to explore the effects of extracellular signal-regulated kinase 5 (ERK5) on lung cancer radioresistance and the associated mechanisms. Our data showed that ERK5 is activated during solid lung cancer development, and ectopic expression of ERK5 promoted cell proliferation and G2/M cell cycle transition. In addition, we found that ERK5 is a potential regulator of radiosensitivity in lung cancer cells. Mechanistic investigations revealed that ERK5 could trigger IR-induced activation of Chk1, which has been implicated in DNA repair and cell cycle arrest in response to DNA double-strand breaks (DSBs). Subsequently, ERK5 knockdown or pharmacological inhibition selectively inhibited colony formation of lung cancer cells and enhanced IR-induced G2/M arrest and apoptosis. In vivo, ERK5 knockdown strongly radiosensitized A549 and LLC tumor xenografts to inhibition, with a higher apoptotic response and reduced tumor neovascularization. Taken together, our data indicate that ERK5 is a novel potential target for the treatment of lung cancer, and its expression might be used as a biomarker to predict radiosensitivity in NSCLC patients.

Hydroxyapatite coating on damaged tooth surfaces by immersion

Lim, Byoung-Ki,Sun, Fangfang,Ryu, Su-Chak,Koh, Kwangnak,Han, Dong-Wook,Lee, Jaebeom Institute of Physics Pub 2009 Biomedical materials Vol.4 No.2

<P>Hydroxyapatite (HAp) was coated on scratched areas of a human tooth and HAp disks by the immersion method in a HAp colloidal solution (⩽20 µm of average diameter dispersed in DI water). The surface morphologies of the scratched area after immersion for 1–3 months were investigated showing that the damaged surfaces were remarkably recovered. Then, the mechanical property and chemical stability of the HAp coating layers on both specimens were determined via the Vickers hardness test and concentration measurement of extracted Ca<SUP>2+</SUP> ions, respectively, after strong acidic treatment. The cellular behavior of mouse calvaria-derived pre-osteoblastic cells (MC3T3-E1) was also examined on the HAp layers regenerated on micro-scratched HAp disks for the purpose of their potential applications on maxillofacial bone conservation and reconstruction for prosthetic dentistry, and artificial disk preparation of a vertebral column. The notable loss of Ca<SUP>2+</SUP> ions under a highly acidic condition was not observed in the layers coated by HAp adsorption, indicating that the coating surface was well adhered with the original surfaces of the respective specimen. Moreover, the HAp adsorption did not adversely affect the adhesion, growth and proliferation of MC3T3-E1 cells on the coated HAp layers for up to 21 days. These results suggest that the HAp coating on the scratched areas of the tooth would be effectively applicable for the development of long-term prevention of micro-cleavage and tooth health supporters to reduce discoloration and further maxillofacial and orthopedic applications.</P>

Back-Calculation Method of Rock Mass Pressure in a Shallow-Buried Super Large-Span Tunnel Using Upper-Bench CD Method

Yanbin Luo,Yunfei Wu,Jianxun Chen,Fangfang Dong,Weiwei Liu,Lijun Chen,Yao Li,Zhou Shi 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.1

Rock mass pressure has always been a research hotspot in the field of tunnel engineering, especially in the super large-span tunnel, which is characterized by flat section, large excavation span, and complex stress field. Based on the Letuan Tunnel (a bi-directional tunnel with eight traffic lanes) of Binlai expressway expansion project in Shandong Province, China, this paper focused on the calculation method of rock mass pressure and the evolution law of load release in the construction process of the super large-span tunnel excavated by upper-bench central diaphragm (CD) method. Based on field measured data of Letuan Tunnel, the deformation behavior of primary lining and the distribution state of rock mass pressure during the tunnel construction were analyzed. According to the bearing mode of supporting structure, the mechanical models of different construction stages were established. Then, the rock mass pressures in different construction stages were back-calculated using mechanical models and compared with the measured values, and the evolution law of load release during the tunnel construction was discussed. The study results show that the tunnel deformation and rock mass pressure were significantly affected by the construction process and support form, and the excavation span was the key factor affecting the stability of rock mass. For the shallow-buried super large-span tunnel constructed by upper-bench CD method, the primary support of upper bench was under eccentric pressure. The comparison between the back-calculated value and the field measured value indicated that they were similar, and the average relative error was 17.23%. According to the concept of load release coefficient proposed in this paper, the load release coefficient after the pilot tunnel ahead (Part I) excavation reached 63%, and the load release coefficient after the pilot tunnel behind excavation (Part II) was 37%, which means that the rock mass pressure of Part I is increased about 59% due to the excavation of Part II.

Regeneration of a Micro-Scratched Tooth Enamel Layer by Nanoscale Hydroxyapatite Solution

Ryu, Su-Chak,Lim, Byoung-Ki,Sun, Fangfang,Koh, Kwang-Nak,Han, Dong-Wook,Lee, Jae-Beom Korean Chemical Society 2009 Bulletin of the Korean Chemical Society Vol.30 No.4

Hydroxyapatite (HAp)-based materials have attracted considerable attention on account of their excellent stability and recrystallization. Nanoscale HAp powders with a mean particle size of 200 nm were used to regenerate the enamel layers of damaged teeth. An artificially scratched tooth was immersed in a nanoscale HAp powder suspension in d.i. water (HAp of 70 wt%) at 37 ${^{\circ}C}$ for a period of 1~3 months. SEM and AFM showed that the scratched surface was ultimately inlaid with HAp after three months and the roughness increased from 2.80 to 5.51. Moreover, the hardness of the neo-generated HAp layer on the crown was similar to that of the innate layer. $Ca^{2+}$ and ${PO_4}^{3-}$ ions from the HAp powders dissolved in d.i. water were precipitated on the tooth to produce cemented pasteson the enamel surface due to its high recrystallizing characteristics, resulting in a hard neo-regenerated HAp layer on the enamel layer. This nanoscale HAp powder solution might be used to heal decayed teeth as well as to develop tooth whitening appliances.

Development and Application of High-Performance Grouting Materials for Anchoring Pipe in Soft Rock Tunnel

Li-xin Zhang,Jianxun Chen,Lijun Chen,Yanbin Luo,Weiwei Liu,Fangfang Dong,Hao Chen,Hao-yang Zhu 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.10

A high-performance grouting material is proposed to enhance the support effect of anchoring pipes in soft rock mass tunnels in this paper. Through mix proportion and strength tests, the initial setting time, compressive strength, and flowability of the grouting material were determined. Furthermore, based on grouting and pulling tests, the recommended parameters of the anchoringpipe were proposed. The results show that pure cement paste is an ideal grouting material for on-site application, demonstrating excellent anchoring, fluidity, high strength, and rapid hardening. Under optimal conditions of water-cement ratio at 0.46 and retarder proportion at 0.4‰, the initial settling time and the compressive strength of the grouting material are approximately 45 minutes and 28.5 MPa within 4 hours, respectively. The anchoring force of an anchoring pipe with a length of 6 m and a diameter of 76 mm can reach 448.9 kN within the same period. A field test involving anchoring pipes and pure cement paste was conducted during tunnel construction, resulting in a substantial reduction of maximum settlement and convergence of the tunnel by 57.53% and 40.48%, respectively. These results demonstrate the effectiveness

2019 Novel Coronavirus (COVID-19) Pneumonia: Serial Computed Tomography Findings

Jiangping Wei,Huaxiang Xu,Jingliang Xiong,Qinglin Shen,Bing Fan,Chenglong Ye,Wentao Dong,Fangfang Hu 대한영상의학회 2020 Korean Journal of Radiology Vol.21 No.4

From December 2019, Coronavirus disease 2019 (COVID-19) pneumonia (formerly known as the 2019 novel Coronavirus [2019nCoV]) broke out in Wuhan, China. In this study, we present serial CT findings in a 40-year-old female patient with COVID-19 pneumonia who presented with the symptoms of fever, chest tightness, and fatigue. She was diagnosed with COVID-19 infection confirmed by real-time reverse-transcriptase-polymerase chain reaction. CT showed rapidly progressing peripheral consolidations and ground-glass opacities in both lungs. After treatment, the lesions were shown to be almost absorbed leaving the fibrous lesions.

The Prolyl Isomerase Pin1 Is a Novel Target of 6,7,4′-Trihydroxyisoflavone for Suppressing Esophageal Cancer Growth

Lim, Tae-Gyu,Lee, Sung-Young,Duan, Zhaoheng,Lee, Mee-Hyun,Chen, Hanyong,Liu, Fangfang,Liu, Kangdong,Jung, Sung Keun,Kim, Dong Joon,Bode, Ann M.,Lee, Ki Won,Dong, Zigang AMERICAN ASSOCIATION FOR CANCER RESEARCH INC 2017 CANCER PREVENTION RESEARCH Vol.10 No.5

<P>Intake of soy isoflavones is inversely associated with the risk of esophageal cancer. Numerous experimental results have supported the anticancer activity of soy isoflavones. This study aimed to determine the anti-esophageal cancer activity of 6,7,4'-trihydroxyisoflavone (6,7,4'-THIF), a major metabolite of daidzein, which is readily metabolized in the human body. Notably, 6,7,4'-THIF inhibited proliferation and increased apoptosis of esophageal cancer cells. On the basis of a virtual screening analysis, Pin1 was identified as a target protein of 6,7,4'-THIF. Pull-down assay results using 6,7,4'-THIF Sepharose 4B beads showed a direct interaction between 6,7,4'-THIF and the Pin1 protein. Pin1 is a critical therapeutic and preventive target in esophageal cancer because of its positive regulation of beta-catenin and cyclin D1. The 6,7,4'-THIF compound simultaneously reduced Pin1 isomerase activity and the downstream activation targets of Pin1. The specific inhibitory activity of 6,7,4'-THIF was analyzed using Neu/Pin1 wild-type (WT) and Neu/Pin1 knockout (KO) MEFs. 6,7,4'-THIF effected Neu/Pin1 WT MEFs, but not Neu/Pin1 KO MEFs. Furthermore, the results of a xenograft assay using Neu/Pin1 WT and KO MEFs were similar to those obtained from the in vitro assay. Overall, we found that 6,7,4'-THIF specifically reduced Pin1 activity in esophageal cancer models. Importantly, 6,7,4'-THIF directly bound to Pin1 but not FKBP or cyclophilin A, the same family of proteins. Because Pin1 acts like an oncogene by modulating various carcinogenesis-related proteins, this study might at least partially explain the underlying mechanism(s) of the anti-esophageal cancer effects of soy isoflavones. (C) 2017 AACR.</P>