Liquid-cooled cold plate for a Li-ion battery thermal management system designed by topology optimization

Yijun Wang,Xuan Quang Duong,Peyman Gholamali Zadeh,정재동 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.4

Modern commercial electric vehicles often have a liquid-based BTMS with excellent heat transfer efficiency and cooling or heating ability. Use of cooling plate has proved to be an effective approach. In the present study, we propose a novel liquid-cold plate employing a topological optimization design based on the globally convergent version of the method of moving asymptotes (GCMMA) method. Comparison with a traditional liquid-cold plate with straight cooling channels revealed that the topology-optimized configuration provides more uniform temperature distribution on the cold plate surface by reducing 48 % of the maximum temperature difference and 57 % of the temperature standard deviation for Q 0 = 1255 W/m 2 . This shows that the topology optimization method is a useful and high-efficiency approach for the innovative design of liquid-cooling plates used for battery thermal management.

A Novel cold plate of battery thermal management system designed by topology optimization

Yijun Wang,Peyman Gholamali Zadeh,Jae Dong Chung 대한설비공학회 2022 대한설비공학회 학술발표대회논문집 Vol.2022 No.6

The cold plate is designed to cool the rectangular lithium-ion battery by topology optimization technique. A two-dimensional model was assumed to save the computing effort and time. In this study, numerical analysis of topology optimization cold plate is implemented using COMSOL Multiphysics R6.0. Numerical results were compared with the reference model which has six straight channels. The results demonstrate that topology optimization cold plate has a significant influence on the temperature uniformity and maximum temperature differences. When the battery heat generation reach to 10W, comparing with reference cold plate, the standard deviation of temperature Tσ and maximum temperature difference (ΔT<SUB>max</SUB> ) of topology optimization cold plate are decreased by 121% and 82%, respectively. This study indicated that topology optimization is more effective for the higher heat generation rate of battery.

Melting performance enhancement of fins based on latent heat thermal energy storage (LHTES) system

Yijun Wang(왕이쥔),Jae Dong Chung(정재동) 대한기계학회 2023 대한기계학회 춘추학술대회 Vol.2023 No.4

Visit-to-Visit Variability of Lipids Measurements and the Risk of Stroke and Stroke Types: A Prospective Cohort Study

Anxin Wang,Haibin Li,Jinhuan Yuan,Yingting Zuo,Yijun Zhang,Shouhua Chen,Shouling Wu,Yongjun Wang 대한뇌졸중학회 2020 Journal of stroke Vol.22 No.1

Background and Purpose Previous studies suggested increased visit-to-visit variability of total cholesterol (TC) is associated with stroke. This study aimed to investigate the associations of various lipids measurements variability and the risk of stroke and stroke type (ischemic and hemorrhagic stroke). Methods Fifty-one thousand six hundred twenty participants in the Kailuan Study without history of myocardial infarction, stroke, and cancer who underwent three health examinations during 2006 to 2010 were followed for incident stroke. Variability in TC, triglycerides, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) measurements were measured using the coefficient of variation (CV), standard deviation (SD), variability independent of the mean (VIM), and average real variability (ARV). Results During a median of 6.04 years of follow-up, 1,189 incident stroke (1,036 ischemic and 160 hemorrhagic stroke) occurred. In the multivariable-adjusted model, the hazard ratio (HR) comparing participants in the highest versus lowest quartile of CV of HDL-C were 1.21 (95% confidence interval [CI], 1.02 to 1.45; P for trend=0.013) for ischemic stroke. The highest quartile of CV of LDL-C was associated with 2.17-fold risk of hemorrhagic stroke (HR, 2.17; 95% CI, 1.25 to 3.75; P for trend=0.002) compared with the lowest quartile. We did not observe any significant association between TC and triglycerides variability with any of stroke. Consistent results were obtained when calculating variability index using SD, VIM, or ARV. Conclusions These findings suggest the high visit-to-visit HDL-C and LDL-C variability were associated with an increased incidence of ischemic and hemorrhagic stroke, respectively.

A Model Stacking Algorithm for Indoor Positioning System using WiFi Fingerprinting

JinQuan Wang,YiJun Wang,GuangWen Liu,GuiFen Chen 한국인터넷정보학회 2023 KSII Transactions on Internet and Information Syst Vol.17 No.4

With the development of IoT and artificial intelligence, location-based services are getting more and more attention. For solving the current problem that indoor positioning error is large and generalization is poor, this paper proposes a Model Stacking Algorithm for Indoor Positioning System using WiFi fingerprinting. Firstly, we adopt a model stacking method based on Bayesian optimization to predict the location of indoor targets to improve indoor localization accuracy and model generalization. Secondly, Taking the predicted position based on model stacking as the observation value of particle filter, collaborative particle filter localization based on model stacking algorithm is realized. The experimental results show that the algorithm can control the position error within 2m, which is superior to KNN, GBDT, Xgboost, LightGBM, RF. The location accuracy of the fusion particle filter algorithm is improved by 31%, and the predicted trajectory is close to the real trajectory. The algorithm can also adapt to the application scenarios with fewer wireless access points.

Construction of porous anodic oxide/Ce-MOFs film by induced electrodeposition and its corrosion resistance

Yijun Cao,Likui Wang,Shichen Lu,Yuqing Wen,Wei Shang 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.122 No.-

Aluminum alloy has good expansion and low hardness. However, aluminum alloy is susceptible to corrosionin humid environments, limiting their application. In this experiment, we adopted an efficientand facile method to prepare porous anodic oxide (PAO) films and PAO/Ce-MOFs composite films. Itcan be characterized by SEM, EDS, FT-IR, XRD, XPS and other test methods. The corrosion resistance isstudied by neutral salt spray test and electrochemical test. Electrochemical data show that the resistanceof PAO/Ce-MOFs film is three orders of magnitude higher than that of aluminum alloy substrate, and thecorrosion current density is three orders of magnitude lower than that of aluminum alloy substrate,reaching 1.621 108 A/cm2. The corrosion resistance efficiency is 99.92%. The salt spray experimentshows that the film can maintain the corrosion resistance for 30d. The results show that Ce-MOFs coatingcan effectively improve the corrosion resistance of aluminum alloy. Therefore, this study provides a newapproach in the application of MOFs materials in the direction of anticorrosion.

Mining Sequential Trees in a Tree Sequence Database

Yijun Bei,Zhen Lin,Qiyao Wang,Erteng Liu 보안공학연구지원센터 2014 International Journal of Database Theory and Appli Vol.7 No.3

Carbon disulfide induces mitochondria-mediated apoptosis in Sertoli-germ cells coculture

Wei Wang,Zhen Zhang,Yinsheng Guo,Yu Dong,Xiaoyu Huang1,Yijun Zhou,Guoyuan Chen 대한독성 유전단백체 학회 2015 Molecular & cellular toxicology Vol.11 No.2

Carbon disulfide (CS2), a common organic solvent, induces a variety of adverse effects in the male reproductive system. In this study, we investigated the cytotoxicity, ultrastructural changes, and potential apoptotic induction mechanisms of CS2 in mixed cultures of Sertoli and germ cells. Sertoli and germ cells were cocultured and treated with CS2 for 24 h. Growth rates were noted, and apoptotic cells were identified by Hoechst 33258 staining. Ultrastructure changes were observed via transmission electron microscopy (TEM). Mitochondrial membrane potential and expressions of apoptosis-related factors (cytochrome c, Bax, Bcl- 2, caspase-3 and caspase-9) were examined by JC-1 staining, western blot, and real-time PCR. The results showed that CS2 treatment was associated with reduced growth rates of Sertoli-germ cells. Ultrastructure changes in Sertoli-germ cells treated with CS2 were typical of apoptosis. In addition, CS2 treatment depolarized mitochondrial membrane potential, upregulated Bax levels and downregulated Bcl-2 levels, released cytochrome c from the mitochondrial intermembrane space to the cytosol, and triggered mitochondria-mediated apoptosis. Subsequently, caspase-9 and caspase-3 were activated, resulting in Sertoli-germ cells apoptosis. The above data suggest that CS2 has adverse effect on the viability of Sertoli-germ cells and induces apoptosis through mitochondrial pathway.

Green catalyst derived from zero‑valent iron onto porous biochar for removal of Rhodamine B from aqueous solution in a Fenton‑like process

Chongqing Wang,Pau Loke Show,Xiuxiu Zhang,Yijun Cao,Yasser Vasseghian 한국탄소학회 2023 Carbon Letters Vol.33 No.7

Organic wastewater causes serious environmental pollution, and catalytic oxidation is promising technique for wastewater treatment. Developing green and effective catalysts is currently challenging. In this work, green synthesis of nano zerovalent iron loaded onto porous biochar derived from popcorn is conducted, and catalytic oxidation of Rhodamine B (RhB) is evaluated in the presence of H2O2. Effect of process factors is examined on catalytic performance for RhB removal. The mechanism of RhB removal is discussed by characterizations (Fourier transform infrared spectra and Raman) and UV–vis spectra. RhB removal is improved with high catalyst dosage, low initial RhB concentration, and high reaction temperature, while it is slightly influenced by carbonization temperature of biochar, H2O2 dosage and pH value. Under conditions of BC-250 1.0 g/L, H2O2 0.01 mol/L, pH 6.1, and temperature 30 °C, the removal rate of RhB is 92.27% at 50 min. Pseudo first-order kinetics is used to fitting experimental data, and the activation energy for RhB removal in BC-250/H2O2 system is 39 kJ/mol. RhB removal in BC-250/H2O2 system can be attributed to adsorption effect and catalytic oxidation with the dominant role of hydroxyl radical. This work gives insights into catalytic oxidation of organic wastewater using green catalyst.

Exosome-mediated lnc-ABCA12-3 promotes proliferation and glycolysis but inhibits apoptosis by regulating the toll-like receptor 4/nuclear factor kappa-B signaling pathway in esophageal squamous cell carcinoma

Junliang Ma,Yijun Luo,Yingjie Liu,Cheng Chen,Anping Chen,Lubiao Liang,Wenxiang Wang,Yongxiang Song 대한약리학회 2023 The Korean Journal of Physiology & Pharmacology Vol.27 No.1

Esophageal squamous cell carcinoma (ESCC) is a kind of malignant tumor with high incidence and mortality in the digestive system. The aim of this study is to explore the function of lnc-ABCA12-3 in the development of ESCC and its unique mechanisms. RT-PCR was applied to detect gene transcription levels in tissues or cell lines like TE-1, EC9706, and HEEC cells. Western blot was conducted to identify protein expression levels of mitochondrial apoptosis and toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB) signaling pathway. CCK-8 and EdU assays were carried out to measure cell proliferation, and cell apoptosis was examined by flow cytometry. ELISA was used for checking the changes in glycolysis-related indicators. Lnc-ABCA12-3 was highly expressed in ESCC tissues and cells, which preferred it to be a candidate target. The TE-1 and EC9706 cells proliferation and glycolysis were obviously inhibited with the downregulation of lnc-ABCA12-3, while apoptosis was promoted. TLR4 activator could largely reverse the apoptosis acceleration and relieved the proliferation and glycolysis suppression caused by lnc-ABCA12-3 downregulation. Moreover, the effect of lnc-ABCA12-3 on ESCC cells was actualized by activating the TLR4/NF-κB signaling pathway under the mediation of exosome. Taken together, the lnc-ABCA12-3 could promote the proliferation and glycolysis of ESCC, while repressing its apoptosis probably by regulating the TLR4/NF-κB signaling pathway under the mediation of exosome.