Determination of flutter derivatives by stochastic subspace identification technique

Xian-rong Qin,Ming Gu 한국풍공학회 2004 Wind and Structures, An International Journal (WAS Vol.7 No.3

Antioxidant capacity, flavor and physicochemical properties of FH06 functional beverage fermented by lactic acid bacteria: a promising method to improve antioxidant activity and flavor of plant functional beverage

Yan Xian-Tao,Zhang Ziqi,Wang Yubao,Zhang Wenmiao,Zhang Longfei,Liu Yang,Chen Dawei,Wang Wenqiong,Ma Wenlong,Qian Jian-Ya,Gu Ruixia 한국응용생명화학회 2023 Applied Biological Chemistry (Appl Biol Chem) Vol.66 No.-

The ability of natural plants to treat chronic diseases is closely related to their antioxidant function. Lactic acid bacteria (LAB) fermentation is an effective way to improve the nutritional value, biological activity and flavor of food. This study investigated the pH, titratable acidity, total polysaccharide, total flavone, total saponin, total polyphenol, and antioxidant activity of the FH06 beverage before and after probiotic fermentation. Results: After fermentation, FH06 had lower contents of total polysaccharides, total flavonoids, total saponins and total polyphenols but higher titratable acidity. The antioxidant activity was tested by total antioxidant capacity (FRAP method) and DPPH· scavenging ability. The FRAP value significantly increased after fermentation (P < 0.05), and the maximum increase was observed for Lactobacillus fermentum grx08 at 25.87%. For DPPH· scavenging ability, the value of all fermentations decreased, and L. fermentum grx08 had the smallest reduction at 2.21% (P < 0.05). The results of GC–MS and sensory analysis showed that fermentation eliminated bad flavors, such as grass, cassia and bitterness, and highlighted the fruit aroma and soft sour taste. Conclusion: The FRAP value and sensory flavor of FH06 fermentation by L. fermentum grx08 were significantly improved, indicating its great potential as a functional food with both strong antioxidant activity and good flavor.

Numerical study on conjugate heat transfer in a liquid-metal-cooled pipe based on a four-equation turbulent heat transfer model

Li Xian-Wen,Su Xing-Kang,Gu Long,Wang Xiang-Yang,Fan Da-Jun 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.5

Conjugate heat transfer between liquid metal and solid is a common phenomenon in a liquid-metalcooled fast reactor's fuel assembly and heat exchanger, dramatically affecting the reactor’s safety and economy. Therefore, comprehensively studying the sophisticated conjugate heat transfer in a liquidmetal-cooled fast reactor is profound. However, it has been evidenced that the traditional Simple Gradient Diffusion Hypothesis (SGDH), assuming a constant turbulent Prandtl number (Prt, usually 0.85 - 1.0), is inappropriate in the Computational Fluid Dynamics (CFD) simulations of liquid metal. In recent decades, numerous studies have been performed on the four-equation model, which is expected to improve the precision of liquid metal’s CFD simulations but has not been introduced into the conjugate heat transfer calculation between liquid metal and solid. Consequently, a four-equation model, consisting of the Abe k ε turbulence model and the Manservisi kq εq heat transfer model, is applied to study the conjugate heat transfer concerning liquid metal in the present work. To verify the numerical validity of the four-equation model used in the conjugate heat transfer simulations, we reproduce Johnson’s experiments of the liquid lead-bismuth-cooled turbulent pipe flow using the four-equation model and the traditional SGDH model. The simulation results obtained with different models are compared with the available experimental data, revealing that the relative errors of the local Nusselt number and mean heat transfer coefficient obtained with the four-equation model are considerably reduced compared with the SGDH model. Then, the thermal-hydraulic characteristics of liquid metal turbulent pipe flow obtained with the four-equation model are analyzed. Moreover, the impact of the turbulence model used in the four-equation model on overall simulation performance is investigated. At last, the effectiveness of the four-equation model in the CFD simulations of liquid sodium conjugate heat transfer is assessed. This paper mainly proves that it is feasible to use the four-equation model in the study of liquid metal conjugate heat transfer and provides a reference for the research of conjugate heat transfer in a liquidmetal-cooled fast reactor

Determination of flutter derivatives by stochastic subspace identification technique

Qin, Xian-Rong,Gu, Ming Techno-Press 2004 Wind and Structures, An International Journal (WAS Vol.7 No.3

Flutter derivatives provide the basis of predicting the critical wind speed in flutter and buffeting analysis of long-span cable-supported bridges. In this paper, one popular stochastic system identification technique, covariance-driven Stochastic Subspace Identification(SSI in short), is firstly presented for estimation of the flutter derivatives of bridge decks from their random responses in turbulent flow. Secondly, wind tunnel tests of a streamlined thin plate model and a ${\Pi}$ type blunt bridge section model are conducted in turbulent flow and the flutter derivatives are determined by SSI. The flutter derivatives of the thin plate model identified by SSI are very comparable to those identified by the unifying least-square method and Theodorson's theoretical values. As to the ${\Pi}$ type section model, the effect of turbulence on aerodynamic damping seems to be somewhat notable, therefore perhaps the wind tunnel tests for flutter derivative estimation of those models with similar blunt sections should be conducted in turbulent flow.

Chinese herbal medicine (Bu-Shen-Tian-Jing Formula) for outcomes of IVF in Chinese patients with polycystic ovary syndrome: A retrospective cohort study

Pan Xiaoming,Gu Yinger,Zhang Xian,Shi Biwei,Cui Long,Wang Fangfang,Qu Fan 한국한의학연구원 2022 Integrative Medicine Research Vol.11 No.1

Background: Polycystic ovary syndrome (PCOS) is one of the most common causes of anovulatory infertility. Chinese herbal medicine (CHM) has many advantages in treating PCOS. We conducted a retrospective cohort study to investigate the effects of CHM (Bu-Shen-Tian-Jing Formula, BSTJF) on the outcomes of IVF in Chinese patients with PCOS and the potential underlying mechanism. Methods: A total of 111 patients with PCOS who undergone IVF between November 2009 and July 2018 were included. Fifty-four patients received a three-month BSTJF therapy before controlled ovarian hyperstimulation, while the other 57 patients didn't. The data of the PCOS patients was collected. Anti-Müllerian hormone (AMH), growth differentiation factor-8 (GDF-8) levels in the follicular fluid were evaluated. Results: BSTJF helped patients with PCOS to get more retrieved oocytes (P<0.05) and fertilized oocytes (P<0.05). The clinical cumulative pregnancy rate, live birth rate, and term delivery rate were significantly higher in the same stimulated cycle of the PCOS patients with BSTJF treatment (P<0.05). No significant differences existed between the two groups in the rate of fertilization, hospitalization rate of ovarian hyper stimulation syndrome and obstetrical or neonatal complications. BSTJF significantly decreased the AMH levels in the follicular fluids (P<0.05). Conclusion: BSTJF significantly may improve the outcomes of IVF in Chinese patients with PCOS through decreasing AMH levels in follicular fluids. However, the evidence is limited due to the small sample size and the several potential bias. Background: Polycystic ovary syndrome (PCOS) is one of the most common causes of anovulatory infertility. Chinese herbal medicine (CHM) has many advantages in treating PCOS. We conducted a retrospective cohort study to investigate the effects of CHM (Bu-Shen-Tian-Jing Formula, BSTJF) on the outcomes of IVF in Chinese patients with PCOS and the potential underlying mechanism. Methods: A total of 111 patients with PCOS who undergone IVF between November 2009 and July 2018 were included. Fifty-four patients received a three-month BSTJF therapy before controlled ovarian hyperstimulation, while the other 57 patients didn't. The data of the PCOS patients was collected. Anti-Müllerian hormone (AMH), growth differentiation factor-8 (GDF-8) levels in the follicular fluid were evaluated. Results: BSTJF helped patients with PCOS to get more retrieved oocytes (P<0.05) and fertilized oocytes (P<0.05). The clinical cumulative pregnancy rate, live birth rate, and term delivery rate were significantly higher in the same stimulated cycle of the PCOS patients with BSTJF treatment (P<0.05). No significant differences existed between the two groups in the rate of fertilization, hospitalization rate of ovarian hyper stimulation syndrome and obstetrical or neonatal complications. BSTJF significantly decreased the AMH levels in the follicular fluids (P<0.05). Conclusion: BSTJF significantly may improve the outcomes of IVF in Chinese patients with PCOS through decreasing AMH levels in follicular fluids. However, the evidence is limited due to the small sample size and the several potential bias.

Two Photon Polymerization Micro/Nanofabrication of Suspended Nanorods in Organically Modified Ceramics

Jieqiong Lin,Xian Jing,Mingming Lu,Yan Gu,Baojun Yu,Jiating Tang,Xu Zheng 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.3

Organically modified ceramics are used as photoresistors in the present work. The role of every ingredient played in two photon polymerization process is analyzed. A simple, compact and easy to locate experimental scheme is designed to fabricate nanorods in Ormocer. Based on the threshold theory of photon intensity, the lateral size dependences and vertical size dependences of nanorods on laser power and scanning speed are investigated, respectively. Through systematically changing processing parameters, a 136 nm Ormocer suspended nanorod which is beyond diffraction limit resolution is obtained when v = 115 µm/s, P = 58.5 mW. By this means, two photon polymerization techniques show great potential to obtain a limiting resolution of Ormocer. What is more, micro gear, micro chair, photonic crystal and micro annular lens are fabricated in two photon polymerization in order to exhibit excellent mechanical and optical property of Ormocer.

Computational Evaluation of Benzene Derivatives Bridged Sulfonylurea Herbicides

Imshik Lee(이임식),GU Hwang,SC Choe,MM Choe,MG Wu,GS Xian,I Lee 한국농약과학회 2019 한국농약과학회 학술발표대회 논문집 Vol.2019 No.4

Effects of graphite additives in electrolytes on the microstructure and corrosion resistance of Alumina PEO coatings

Guo-Hua Lv,Huan Chen,Wei-Chao Gu,Wen-Ran Feng,Li Li,Er-Wu Niu,Xian-Hui Zhang,Si-Ze Yang 한국물리학회 2009 Current Applied Physics Vol.9 No.3

In the present work, graphite grains of different sizes were added into the electrolyte to prepare ceramic coatings on aluminum by plasma electrolytic oxidation (PEO). Scanning electron microscopy (SEM) coupled with an energy dispersive X-ray analysis system (EDX), Raman spectroscopy and X-ray diffractometer (XRD) were used to characterize the coatings. A three-electrode system was used to evaluate the corrosion performances of the coatings in a 3.5 wt.% NaCl solution. It was found that the morphology and corrosion performance of the coatings were significantly influenced by the size of the graphite grains. Compared with bigger graphite grains, finer ones were involved in the oxidation process and embedded within the ceramic coatings, which made the coatings less porous and more compact. Thus, the corrosion resistance of the coatings with embedded graphite grains was greatly improved. In the present work, graphite grains of different sizes were added into the electrolyte to prepare ceramic coatings on aluminum by plasma electrolytic oxidation (PEO). Scanning electron microscopy (SEM) coupled with an energy dispersive X-ray analysis system (EDX), Raman spectroscopy and X-ray diffractometer (XRD) were used to characterize the coatings. A three-electrode system was used to evaluate the corrosion performances of the coatings in a 3.5 wt.% NaCl solution. It was found that the morphology and corrosion performance of the coatings were significantly influenced by the size of the graphite grains. Compared with bigger graphite grains, finer ones were involved in the oxidation process and embedded within the ceramic coatings, which made the coatings less porous and more compact. Thus, the corrosion resistance of the coatings with embedded graphite grains was greatly improved.

Elongation Prediction of Steel-Strips in Annealing Furnace with Deep Learning via Improved Incremental Extreme Learning Machine

Chao Wang,Jian-Hui Wang,Shu-Sheng Gu,Xiao Wang,Yu-Xian Zhang 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.3

The elongation of steel-strips in annealing furnace is an important factor that affects the position ofwelding line and safety of air-knife since there is no extra space to install welding line detector in field conditions. Therefore, predicting the elongation of steel-strips in the annealing process is important to fulfill the requirementsof eliminating security risks and improving economic performance. In this paper, we propose a deep architecturescalled I-ELM/MLCSA autoencoders with the concept of stacked generalization philosophy to solve large and complexdata mining problems. The comparison results of the case studies indicate that D-ELMs-AE/MLCSA is apromising prediction algorithm and can be employed for steel-strips elongation predictions with excellent performance.

MiR-421 Regulates Apoptosis of BGC-823 Gastric Cancer Cells by Targeting Caspase-3

Wu, Jian-Hong,Yao, Yong-Liang,Gu, Tao,Wang, Ze-You,Pu, Xiong-Yong,Sun, Wang-Wei,Zhang, Xian,Jiang, Yi-Biao,Wang, Jian-Jun Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.13

MicroRNAs might act as oncogenes or tumor suppressors in cancer. Recent studies have shown that miR-421 is up-regulated in human gastric cancer. Here, we found that miR-421 was over-expressed in gastric cancer tissues and cell lines. Bioinformatics analysis predicted that the caspase-3 gene was a target of miR-421. Caspase-3 was negatively regulated by miR-421 at the post-transcriptional level. Bax and Bcl-2 were also regulated by miR-421. Moreover, tumor necrosis factor receptor-I and -II, death receptors in the apoptosis pathway, were up-regulated by miR-421. The over-expression of miR-421 promoted gastric cancer cell growth and inhibited apoptosis of the BGC-823 gastric cancer cell line. These observations indicate that miR-421 acts as a tumor promoter by targeting the caspase-3 gene and preventing apoptosis of gastric cancer cells through inhibition of caspase-3 expression. These findings contribute to our understanding of the functions of miR-421 in gastric cancer.