Spatial Prediction of Soil Variables Based on Primary Terrain Attributes in a Gentle Area

Xiaodong Song,Ganlin Zhang,Feng Liu 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Fatigue behavior of GFRP-concrete composite decks: An experimental and numerical study

Xiaodong Song,Yili Huang,Qiao Huang,Huakai Zheng 국제구조공학회 2021 Structural Engineering and Mechanics, An Int'l Jou Vol.80 No.3

In order to ensure the safety of glass fiber reinforced polymer (GFRP)-concrete composite bridge deck, its static and fatigue behaviors were studied by both experimental and numerical method in this paper. First, static and fatigue loading tests were carried out to investigate the mechanical properties of the GFRP-concrete composite slab. The experimental results indicated that the composite bridge deck had a good fatigue resistance. Then, a finite element model was built and the accuracy of the model was verified by comparing the simulated results with the static experiment. Third, corresponding constitutive models and failure criterions were introduced to simulate the fatigue performance of GFRP-concrete composite slab by using both finite element method and theoretical layered method. Generally, the calculated values were in good agreement with the test values, and the proposed method can be used to predict the deflection and strain of the components. Finally, parametric analysis was conducted to investigate the stiffness degradation of the composite structure.

Continuous-Current Mode Operation of a Semi-Dual-Bridge Resonant Converter

Song Hu,Ming Lu,Xiaodong Li 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

Originated from the dual-bridge resonant converter, a semi-dual-bridge resonant converter is proposed for unidirectional applications in this paper. The single phase-shift modulation is adopted for power regulation. It is proved that the proposed converter is capable to work in either continuous-current mode or discontinuous-current mode. Compared with the dual-bridge resonant converter with single phase-shift modulation, the high circulation energy in output bridge is eliminated and the zero-voltage switching range of all switches is extended in the proposed converter. Steady-state analysis of the converter in continuous-current mode is performed using fundamental harmonics approximation. A design example based on the analysis results is presented and then verified through both simulation and experimental test on a lab prototype converter.

Immobilization of ammonium and phosphate in aqueous solution by zeolites synthesized from fly ashes with different compositions

Xiaodong Ji,Mulan Zhang,Yujie Wang,Yichu Song,Yaoyao Ke,Yunqi Wang 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.22 No.-

Immobilization of ammonium and phosphate by zeolites synthesized from low-calcium (LC-Z) and highcalcium (HC-Z) fly ashes is studied. LC-Z has higher ammonium immobilization capacity while HC-Z has better performance in phosphate uptake. As part of Ca2+ released from HC-Z compete with ammonium the exchangeable sites in LC-Z, LC-Z can affect phosphate immobilization of HC-Z, and HC-Z also lowers ammonium uptake of LC-Z. Separate dosing of LC-Z and HC-Z, i.e., first LC-Z and then HC-Z, is proved better than mixed dosing at simultaneous immobilization of ammonium and phosphate. The effect parameters for phosphate and ammonium immobilization of LTH-Z are investigated.

A Control Method to Make LQR Robust: A Planes Cluster Approaching Mode

Xiaodong Liu,Yunjie Wu,Yu Zhang,Song Xiao 제어·로봇·시스템학회 2014 International Journal of Control, Automation, and Vol.12 No.2

Linear quadratic regulator (LQR) is an optimal controller being used for linear systems, and it can minimize the comprehensive quadratic performance index (QPI) with respect to convergence error and control consumption. However, LQR lacks the robust property to cope with parameter perturbations and external disturbances. Aiming at the above deficiency of LQR, a robust LQR (RLQR) is proposed for linear systems under the guideline of planes cluster approaching mode (PCAM). In the proposed RLQR, one nonlinear item is introduced into control law, and it cooperates with the other linear item to guarantee the global asymptotic stability in the presence of equivalent disturbances. The conditions of global asymptotic stability are deduced by the method of Lyapunov function. Simulation results present that, the chosen LTI plant using RLQR possesses smaller QPI in the existence of time-varying disturbances, compared with the conventional LQR and sliding mode controller (SMC).

HLA–DPB1 and DPB2 are genetic loci for systemic sclerosis: A genome-wide association study in Koreans with replication in North Americans

Zhou, Xiaodong,Lee, Jong Eun,Arnett, Frank C.,Xiong, Momiao,Park, Min Young,Yoo, Yeon Kyeong,Shin, Eun Soon,Reveille, John D.,Mayes, Maureen D.,Kim, Jin Hyun,Song, Ran,Choi, Ji Yong,Park, Ji Ah,Lee, Y Wiley Subscription Services, Inc., A Wiley Company 2009 Vol.60 No.12

<B>Objective</B><P>To identify systemic sclerosis (SSc) susceptibility loci via a genome-wide association study.</P><B>Methods</B><P>A genome-wide association study was performed in 137 patients with SSc and 564 controls from Korea using the Affymetrix Human SNP Array 5.0. After fine-mapping studies, the results were replicated in 1,107 SSc patients and 2,747 controls from a US Caucasian population.</P><B>Results</B><P>The single-nucleotide polymorphisms (SNPs) (rs3128930, rs7763822, rs7764491, rs3117230, and rs3128965) of HLA–DPB1 and DPB2 on chromosome 6 formed a distinctive peak with log P values for association with SSc susceptibility (P = 8.16 × 10<SUP>−13</SUP>). Subtyping analysis of HLA–DPB1 showed that DPB1*1301 (P = 7.61 × 10<SUP>−8</SUP>) and DPB1*0901 (P = 2.55 × 10<SUP>−5</SUP>) were the subtypes most susceptible to SSc in Korean subjects. In US Caucasians, 2 pairs of SNPs, rs7763822/rs7764491 and rs3117230/rs3128965, showed strong association with SSc patients who had either circulating anti–DNA topoisomerase I (P = 7.58 × 10<SUP>−17</SUP>/4.84 × 10<SUP>−16</SUP>) or anticentromere autoantibodies (P = 1.12 × 10<SUP>−3</SUP>/3.2 × 10<SUP>−5</SUP>), respectively.</P><B>Conclusion</B><P>The results of our genome-wide association study in Korean subjects indicate that the region of HLA–DPB1 and DPB2 contains the loci most susceptible to SSc in a Korean population. The confirmatory studies in US Caucasians indicate that specific SNPs of HLA–DPB1 and/or DPB2 are strongly associated with US Caucasian patients with SSc who are positive for anti–DNA topoisomerase I or anticentromere autoantibodies.</P>

Clustering Strategy Based on Graph Method and Power Control for Frequency Resource Management in Femtocell and Macrocell Overlaid System

Hongjia Li,Xiaodong Xu,Dan Hu,Xiaofeng Tao,Ping Zhang,Song Ci,Hui Tang 한국통신학회 2011 Journal of communications and networks Vol.13 No.6

In order to control interference and improve spectrumef-ficiency in the femtocell and macrocell overlaid system (FMOS), we propose a joint frequency bandwidth dynamic division, clustering and power control algorithm (JFCPA) for orthogonal-frequencydivision-multiple access-based downlink FMOS. The overall system bandwidth is divided into three bands, and the macro-cellular coverage is divided into two areas according to the intensity of the interference from the macro base station to the femtocells, which are dynamically determined by using the JFCPA. A cluster is taken as the unit for frequency reuse among femtocells. We map the problem of clustering to the MAX k-CUT problem with the aim of eliminating the inter-femtocell collision interference, which is solved by a graph-based heuristic algorithm. Frequency bandwidth sharing or splitting between the femtocell tier and the macrocell tier is determined by a step-migration-algorithm-based power control. Simulations conducted to demonstrate the effectiveness of our proposed algorithm showed the frequency-reuse probability of the FMOS reuse band above 97.6% and at least 70% of the frequency bandwidth available for the macrocell tier, which means that the co-tier and the cross-tier interference were effectively controlled. Thus, high spectrum efficiency was achieved. The simulation results also clarified that the planning of frequency resource allocation in FMOS should take into account both the spatial density of femtocells and the interference suffered by them. Statistical results from our simulations also provide guidelines for actual FMOS planning.

Deflection calculation method on GFRP-concrete-steel composite beam

Zhaojie Tong,Xiaodong Song,Qiao Huang 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.26 No.5

A calculation method was presented to calculate the deflection of GFRP-concrete-steel beams with full or partial shear connections. First, the sectional analysis method was improved by considering concrete nonlinearity and shear connection stiffness variation along the beam direction. Then the equivalent slip strain was used to take into consideration of variable crosssections. Experiments and nonlinear finite element analysis were performed to validate the calculation method. The experimental results showed the deflection of composite beams could be accurately predicted by using the theoretical model or the finite element simulation. Furthermore, more finite element models were established to verify the accuracy of the theoretical model, which included different GFRP plates and different numbers of shear connectors. The theoretical results agreed well with the numerical results. In addition, parametric studies using theoretical method were also performed to find out the effect of parameters on the deflection. Based on the parametric studies, a simplified calculation formula of GFRP-concrete-steel composite beam was exhibited. In general, the calculation method could provide a more accurate theoretical result without complex finite element simulation, and serve for the further study of continuous GFRP-concrete-steel composite beams.

Experimental and Theoretical Study on the Flexural Performance of GFRP-Concrete-Steel Composite Beams

Zhaojie Tong,Xiaodong Song,Qiao Huang 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.8

A novel GFRP (glass fiber-reinforced polymer)-concrete-steel composite beam bridge was proposed to prolong the service life of bridges. In order to investigate the flexural behavior of the composite beams, four-point bending tests and push-out tests were conducted. First, GFRP-concrete-steel composite beams with different interface types were fabricated and tested. Experimental results indicated the concrete ultimate strain and the ultimate deflection were increased because of the confining effect provided by GFRP plates. The GFRP-concrete interface had no obvious effect on flexural stiffness and flexural capacity. The slip effect of GFRPconcrete- steel beams was similar to that of steel-concrete beams. The failure process of GFRP-concrete-steel beams was different from that of steel-concrete beams due to the effect of the GFRP plate. Then, push-out specimens were tested to investigate the slip effect between GFRP-concrete decks and steel beams. The effect of GFRP plates on the studs was insignificant because of the large stud hole, and a regression formula of load-slip relationship was presented based on the experimental results. Finally, finite element model and theoretical model were employed to analyze the deflection calculation method and the flexural capacity calculation method, respectively.

Assessment of physiological changes and body movement during sleep in patient with breathing pattern disorders and stroke

( Tiejun Miao ),( Xiaodong Yuan ),( Pingshu Zhang ),( Jun Song ) 한국감성과학회 2019 한국감성과학회 국제학술대회(ICES) Vol.2019 No.-

Healthy adults and patients with history of breathing disorders and stroke were enrolled in this clinical study and underwent simultaneous test by polysomnography (PSG). The present study analyzed fluctuation in vital signs and movement activity extracted from the multichannel ballistocardiographic signals based on piezo sensor distribution under bed mattress. We assessed the validity using contact less technology to screening obstructive sleep apnea and stroke. We found an agreement of apnea-hypopnea index (AHI) with the number of hypopneas estimated by our method. Also we found abnormal changes in body pressure distribution during sleep in patient having history of stroke. Mean area of distribution for stroke was 3.44±0.82 having significant lower values than ones without stroke who had value of 9.19±2.35.