Experimental evaluation of aerodynamic damping of square super high-rise buildings

Yong Quan,Ming Gu,Yukio Tamura 한국풍공학회 2005 Wind and Structures, An International Journal (WAS Vol.8 No.5

Effects of vertical ribs protruding from facades on the wind loads of super high-rise buildings

Yong Quan,Fangchao Hou,Ming Gu 한국풍공학회 2017 Wind and Structures, An International Journal (WAS Vol.24 No.2

The auxiliary structures of a high-rise building, such as balconies, ribs, and grids, are usually much smaller than the whole building; therefore, it is difficult to simulate them on a scaled model during wind tunnel tests, and they are often ignored. However, they may have notable effects on the local or overall wind loads of the building. In the present study, a series of wind pressure wind tunnel tests and high-frequency force balance (HFFB) wind tunnel tests were conducted on rigid models of an actual super high-rise building with vertical ribs protruding from its facades. The effects of the depth and spacing of vertical ribs on the mean values, fluctuating values and the most unfavorable values of the local wind pressure coefficients were investigated by analyzing the distribution of wind pressure coefficients on the facades and the variations of the wind pressure coefficients at the cross section at 2/3 of the building height versus wind direction angle. In addition, the effects of the depth and spacing of vertical ribs on the mean values, fluctuating values and power spectra of the overall aerodynamic force coefficients were studied by analyzing the aerodynamic base moment coefficients. The results show that vertical ribs significantly decrease the most unfavorable suction coefficients in the corner recession regions and edge regions of facades and increase the mean and fluctuating along-wind overall aerodynamic forces.

Comparative analysis of the wind characteristics of three landfall typhoons based on stationary and nonstationary wind models

Yong Quan,Guo Qiang Fub,Zi Feng Huang,Ming Gu 한국풍공학회 2020 한국풍공학회지 Vol.24 No.4

The statistical characteristics of typhoon wind speed records tend to have a considerable time-varying trend; thus, the stationary wind model may not be appropriate to estimate the wind characteristics of typhoon events. Several nonstationary wind speed models have been proposed by pioneers to characterize wind characteristics more accurately, but comparative studies on the applicability of the different wind models are still lacking. In this study, three landfall typhoons, Ampil, Jongdari, and Rumbia, recorded by ultrasonic anemometers atop the Shanghai World Financial Center (SWFC), are used for the comparative analysis of stationary and nonstationary wind characteristics. The time-varying mean is extracted with the discrete wavelet transform (DWT) method, and the time-varying standard deviation is calculated by the autoregressive moving average generalized autoregressive conditional heteroscedasticity (ARMA-GARCH) model. After extracting the time-varying trend, the longitudinal wind characteristics, e.g., the probability distribution, power spectral density (PSD), turbulence integral scale, turbulence intensity, gust factor, and peak factor, are comparatively analyzed based on the stationary wind speed model, time-varying mean wind speed model and time-varying standard deviation wind speed model. The comparative analysis of the different wind models emphasizes the significance of the nonstationary considerations in typhoon events. The time-varying standard deviation model can better identify the similarities among the different typhoons and appropriately describe the nonstationary wind characteristics of the typhoons.

Evaluation the Fertilization of Porcine In Vitro Matured Oocyte using by Ex Vivo Model

Yongquan Han,Dibyendu Biswas,Sang-Hwan Hyun 한국동물생명공학회(구 한국동물번식학회) 2017 발생공학 국제심포지엄 및 학술대회 Vol.2017 No.10

Porcine uterine ex vivo model is a useful tool for investigating gamete maturation, activation, fertilization and early embryonic development. This study was to evaluate fertilization ability of in vitro matured (IVM) porcine oocyte (MII) using porcine uterine ex vivo model. IVM-MII oocytes were fertilized with 7.5×107, 15×107 and 30×107 sperm for 20min in porcine uterine ex vivo model. And, the oocytes were then flushed and performed in vitro culture (IVC). IVM-MII oocytes used for in vitro fertilization (IVF) served as control 1. Before IVF, IVM-MII oocytes cultured in porcine uterine ex vivo model for 20min served as control 2. In the results, it was found that the sperm penetration rate in the control 2 (73.0±4.2) was significantly higher than the other treatment group: 7.5×107 (29.7±4.4), 15×107 (34.3±3.2) and 30×107 (44.3±7.4). But there was no significant difference between control 1 and control 2. Monospermic penetration rate in all treatment groups was significantly higher than control groups, and polyspermy rate in all treatment group was also significantly lower than control groups. These results suggested that porcine uterine ex vivo model improved monospermic penetration by reducing sperm penetration ratio. In the further study, it is required to evaluate the embryonic development, GSH and ROS accumulation levels of MII oocytes fertilized using porcine uterine ex vivo model.

Cloud Task Scheduling Based on Proximal Policy Optimization Algorithm for Lowering Energy Consumption of Data Center

Yongquan Yang,Cuihua He,Bo Yin,Zhiqiang Wei,Bowei Hong 한국인터넷정보학회 2022 KSII Transactions on Internet and Information Syst Vol.16 No.6

As a part of cloud computing technology, algorithms for cloud task scheduling place an important influence on the area of cloud computing in data centers. In our earlier work, we proposed DeepEnergyJS, which was designed based on the original version of the policy gradient and reinforcement learning algorithm. We verified its effectiveness through simulation experiments. In this study, we used the Proximal Policy Optimization (PPO) algorithm to update DeepEnergyJS to DeepEnergyJSV2.0. First, we verify the convergence of the PPO algorithm on the dataset of Alibaba Cluster Data V2018. Then we contrast it with reinforcement learning algorithm in terms of convergence rate, converged value, and stability. The results indicate that PPO performed better in training and test data sets compared with reinforcement learning algorithm, as well as other general heuristic algorithms, such as First Fit, Random, and Tetris. DeepEnergyJSV2.0 achieves better energy efficiency than DeepEnergyJS by about 7.814%.

The greater Eurasian partnership and the Belt and Road Initiative: Can the two be linked?

Yongquan Li 한양대학교 아태지역연구센터 2018 Journal of Eurasian Studies Vol.9 No.2

Responding to changes in the world, Russia has proposed the Greater Eurasian Partnership for the international cooperation agenda. At the same time, the possibility of linking that partnership with the Belt and Road Initiative for international cooperation is one of the key factors in implementing this agenda. Alignment between the development strategies of Russia and China in the field of global, regional, and bilateral relations lays the foundation of successful cooperation between a number of countries, regions, and organizations. For the Eurasian Partnership to succeed, it must strictly adhere toWTO rules and take a tolerant attitude toward the diverse mechanisms for cooperation that various countries and regions have developed.

Web Data Extraction Based on Ensemble Learning

Yongquan Dong,Qiang Chu,Ping Ling 보안공학연구지원센터 2015 International Journal of Database Theory and Appli Vol.8 No.3

With the rapid development of Internet technology, Web has become a huge information source with massive amounts of data. But these data are usually embedded in the semi-structured pages. In order to use these data effectively, the primary problem is to extract the data and store them in structured form. Most of current approaches use a single classifier to extract web data, but relying on a single classifier is not sufficient and different classifier has different performance for the same problem. In this paper, we use the method of ensemble learning for web data extraction. Firstly, we parse the page as a Dom tree, identify the main data regions, and construct feature sets of text nodes in the region. Secondly, we choose multiple kinds of base classifiers (SVM, KNN and Random Forest) to build classification models and then use the linear method to integrate results of each classification model. Finally, we combine integration results with heuristic rules to get the final extraction results. The experiment results show that our approach outperforms the baseline approaches and has a good robustness.

Rapid Analysis of Tetraconazole Residues in Fruits and Vegetables using Ethyl Acetate Extraction and Gas Chromatography-tandem Mass Spectrometry

Yongquan Zheng,Jun Xu,Fengshou Dong,Xingang Liu,Jing Li,Yuanbo Li,,Weili Shan 대한화학회 2011 Bulletin of the Korean Chemical Society Vol.32 No.12

A method based on ethyl acetate extraction and gas chromatography with tandem mass spectrometry was developed for determining tetraconazole residues in fruits and vegetables. A 10 g homogenized sample was mixed with 10 mL ethyl acetate, shaken vigorously for 3 min, stored at −20 oC for 15 min, and then vortexed vigorously for 1 min; 1 g NaCl and 4 g anhydrous MgSO4 were added. The clean-up was carried out by applying dispersive solid-phase with 150 mg MgSO4 and 50 mg primary secondary amine. Three precursor product ion transitions for tetraconazole were measured and evaluated to provide the maximum degree of confidence. Average recoveries in fruits and vegetables at three levels (0.005, 0.05 and 0.5 mg/kg) ranged from 85.53% to 110.66% with relative standard deviations (RSDr) from 1.3% to 17.5%. The LODs ranged from 0.002 to 0.004 μg/kg, and LOQs ranged from 0.006 to 0.012 μg/kg. This method was also applied to determine tetraconazole residue in cucumber dissipation experiment under field conditions. The half-lives of tetraconazole in cucumber were in the range of 2.1-3.1 days.

Effect of Ex Vivo Model of Porcine Uterus on the Fertilization Ability of Porcine Blastocysts Produced In Vitro

Yongquan Han,Sang-Hwan Hyun 한국동물생명공학회(구 한국동물번식학회) 2018 발생공학 국제심포지엄 및 학술대회 Vol.2018 No.06

The success of in vitro embryo production (IVP) demonstrates that it’s possible to bypass the oviduct throughout early development. However, several studies show that embryos developed in vivo are superior to embryos developed in vitro. Using an ex vivo model of porcine uterus is one of the strategies to investigate fertilization within the oviductal environment. During this study, in vitro matured porcine oocytes (MII) were fertilized with 7.5×107, 15×107 and 30×107 sperm cell for 20 min in porcine uterine ex vivo model. The oocytes were then flushed and performed in vitro culture (IVC) at 39°C for 168 hours under 5% O2, 5% CO2. MII oocytes used for in vitro fertilization (IVF) served as control-1. Before IVF, MII oocytes cultured in porcine uterine ex vivo model for 20 min served as control-2. Within the results, penetration rate, MPN formation, monospermy, polyspermy, and efficiency of fertilization had not shown significant difference between control-1 and control-2 group, respectively. However, penetration rate (treatments: 29.7±4.4, 34.3±3.2, 44.3±7.4 vs. 80.0±1.7), polyspermy (treatments: 5.7±5.7, 9.7±5.8, 8.0±4.0 vs. 33.7±9.5) and efficiency of fertilization (treatments: 23.7±2.3, 29.0±3.6, 35.0±4.6 vs. 43.0±5.8) were significantly decreased in treatment groups compared to control-1 (p<0.05). GSH accumulated levels were significantly decreased in 30×107 sperm cell treated group compared to control-1 (p<0.05) and there was no significant difference in ROS accumulated levels among the groups. For embryo development, the cleavage rate and blastocyst rate had not shown significant difference between control-1 and control-2 group. However, the cleavage rate (treatments: 16.3±2.6, 20.1±2.7, 40.7±13.4 vs. 69.5±6.3, 74.2±3.4) was significantly decreased in treatment groups compared to control-1 and control-2 (p<0.05). And the cleavage rate in the treatment group of 30×107 (40.7±13.4) was significantly higher than the treatment group of 7.5×107 (16.3±2.6) (p<0.05). The blastocyst rate (treatments: 31.7±4.0, 25.7±4.0, 26.7±6.5 vs. 7.2±2.4, 9.9±3.0) was significantly increased in control-1, control-2 and the treatment group of 30×107 compared to 7.5×107 and 15×107 (p<0.05). Therefore, these results suggest that ex vivo model may decrease the penetration rate and efficiency of fertilization by reducing GSH accumulated levels. Cleavage rate and blastocyst rate can be promoted by increasing sperm number during ex vivo fertilization.

Effect of porcine uterus as <i>ex vivo</i> model of fertilizing ability and gene expression pattern on blastocysts

Han, Yongquan,Biswas, Dibyendu,Yoon, Junchul David,Jeon, Yubyeol,Hyun, Sang Hwan Elsevier 2019 Theriogenology Vol.129 No.-

<P><B>Abstract</B></P> <P>The success of <I>in vitro</I> embryo production demonstrates that the oviduct can be bypassed during early embryonic development. Using an <I>ex vivo</I> model of porcine uterus is one of the strategies used to investigate fertilization within the oviductal environment. In this study, <I>in vitro</I>-matured porcine oocytes (MII) were fertilized with 7.5 × 10<SUP>7</SUP>, 15 × 10<SUP>7</SUP>, or 30 × 10<SUP>7</SUP> sperm cells for 20 min in the oviduct of a porcine uterine <I>ex vivo</I> model. MII oocytes used for <I>in vitro</I> fertilization (IVF) served as control 1; those cultured in the oviduct of the <I>ex vivo</I> model for 20 min before IVF served as control 2. In present study, the penetration rate, polyspermy, and fertilization efficiency, and accumulated reactive oxygen species (ROS) levels in the treatment groups were significantly decreased compared to those in the control 1 group. During embryonic development, the cleavage rates in the treatment groups were significantly lower than those in the control groups. The cleavage rate in the 30 × 10<SUP>7</SUP> sperm cell-treated group was higher than that in the 7.5 × 10<SUP>7</SUP> sperm cell-treated group. The blastocyst formation rate in control 1 and 2, and 30 × 10<SUP>7</SUP> sperm cell-treated groups increased compared to that in the 7.5 and 15 × 10<SUP>7</SUP> sperm cell-treated groups. <I>PCNA</I>, <I>HSP70.2</I>, and <I>GLUT1</I> were upregulated in the treatment groups and <I>POU5F1</I>, <I>BAX</I>, <I>GPX1</I> were upregulated in the treatment and control 2 groups, compared to the control 1 group. These results suggest that an <I>ex vivo</I> model may decrease the penetration rate and fertilization efficiency by increasing the accumulated ROS levels and inducing the expression of apoptosis- and stress-related genes. However, the model improved the monospermy rate and expression of embryo developmental competence genes. This is the first study that evaluates the effect of an <I>ex vivo</I> model of porcine uterus on fertilization parameters, and the development of porcine embryos.</P> <P><B>Highlights</B></P> <P> <UL> <LI> An <I>ex vivo</I> model may decrease the penetration rate and fertilization efficiency. </LI> <LI> The model improved the monospermy rate and expression of embryo developmental competence genes. </LI> <LI> The <I>ex vivo</I> model increase the accumulated ROS levels and expression of apoptosis- and stress-related genes in embryos. </LI> </UL> </P>