Indoor Location Algorithm Based on Kalman Filter and Multi-Source Data Integration

Zhang Ya-qiong,Li Zhao-xing,Li Xin,Lv Zhihan-han 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.4

For onboard single-station passive direction-finding and location, if there is any abnormal error in the observation data, the extended Kalman filter (EKF) algorithm adopted thereby will cause inaccurate location result. In order to improve algorithm robustness, the robust equivalent gain matrix is constructed according to the standardized prediction residual error and the robust EKF algorithm is applied to the onboard single-station passive direction-finding and location. In allusion to the low efficiency of the robust EKF algorithm, the single-station passive location algorithm based on the improved extended Kalman filter is proposed in this article on the basis of combining F distribution statistic, and meanwhile single abnormal error and continuous abnormal error are added in the observation value to test the algorithm resistance to different abnormal errors. The simulation shows that the algorithm proposed in this article can well weaken the influence of abnormal errors on position estimation and the algorithm based on F distribution discriminant can improve location efficiency.

Voice Activity Detection Algorithm based on Improved Radial Basis Function Neural Network

Bao-yuan Chen,Ya-qiong Lan,Jing-yang Liu,Zi-he Li,Xiao-yang Yu 보안공학연구지원센터 2014 International Journal of Signal Processing, Image Vol.7 No.5

Voice activity detection (VAD) is the key of voice recognition, voice synthesis and speech-sound enhancement.For the sake of improve the accuracy and robustness of speech endpoint detection system. Combining the advantages of adaptive genetic algorithm (AGA) and improved radial basis function network (RBF) defects in existing learning methods. This paper presents a comprehensive detection method-- Adaptive genetic algorithm radial basis function network. This method uses adaptive genetic algorithm to simultaneously optimize the center, the width and the structure of RBF network. The method using wavelet analysis to extract the characteristics of the speech signal, use them as an input amount to the radial basis function networks. Establish voice detection system model, this method enhance the accuracy of the detection system and has better robustness.

Stress wave propagation in clearance joints based on characteristics method

Ya-Qiong Tang,Tuan-Jie Li,Cong-Cong Chen,Zuo-Wei Wang 국제구조공학회 2017 Structural Engineering and Mechanics, An Int'l Jou Vol.62 No.6

In this paper, a stress wave model is established to describe the three states (separate, contact and impact) of clearance joints. Based on this stress wave model, the propagation characteristics of stress wave generated in clearance joints is revealed. First, the stress wave model of clearance joints is established based on the viscoelastic theory. Then, the reflection and transmission characteristics of stress wave with different boundaries are studied, and the propagation of stress wave in viscoelastic rods is described by the characteristics method. Finally, the stress wave propagation in clearance joints with three states is analyzed to validate the proposed model and method. The results show the clearance sizes, initial axial speeds and material parameters have important influences on the stress wave propagation, and the new stress waves will generate when the clearance joint in contact and impact states, and there exist some high stress region near contact area of clearance joints when the incident waves are superposed with reflection waves, which may speed up the damage of joints.

Diffusion of CO₂ Molecules in Polyethylene Terephthalate/Polylactide Blends Estimated by Molecular Dynamics Simulations

Liao, Li-Qiong,Fu, Yi-Zheng,Liang, Xiao-Yan,Mei, Lin-Yu,Liu, Ya-Qing Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.3

Molecular dynamics (MD) simulations have been used to study the diffusion behavior of small gas molecules ($CO_2$) in polyethylene terephthalate (PET)/polylactide (PLA) blends. The Flory-Huggins interaction parameters (${\chi}$) determined from the cohesive energy densities are smaller than the critical value of Flory-Huggins interaction parameters (${\chi}_{critical}$), and that indicates the good compatibility of PET/PLA blends. The diffusion coefficients of $CO_2$ are determined via MD simulations at 298 K. That the order of diffusion coefficients is correlated with the availably fractional free volume (FFV) of $CO_2$ in the PET/PLA blends means that the FFV plays a vital role in the diffusion behavior of $CO_2$ molecules in PET/PLA blends. The slopes of the log (MSD) as a function of log (t) are close to unity over the entire composition range of PET/PLA blends, which confirmes the feasibility of MD approach reaches the normal diffusion regime of $CO_2$ in PET/PLA blends.

Bone Morphogenetic Protein 9 Overexpression Reduces Osteosarcoma Cell Migration and Invasion

Zilan Lv,Ya-guang Weng,Dandan Yang,Jie Li,Min Hu,Min Luo,Xiaoqin Zhan,Peipei Song,Chen Liu,Huili Bai,Baolin Li,Yang Yang,Yingying Chen,Qiong Shi 한국분자세포생물학회 2013 Molecules and cells Vol.36 No.2

Transforming growth factor- (TGF-) is known to pro-mote tumor migration and invasion. Bone morphogenetic proteins (BMPs) are members of the TGF- family expressed in a variety of human carcinoma cell lines. The role of bone morphogenetic protein 9 (BMP9), the most powerful osteogenic factor, in osteosarcoma (OS) progression has not been fully clarified. The expression of BMP9 and its receptors in OS cell lines was analyzed by RT-PCR. We found that BMP9 and its receptors were expressed in OS cell lines. We further investigated the influence of BMP9 on the biological behaviors of OS cells. BMP9 overexpression in the OS cell lines 143B and MG63 inhibited in vitro cell migration and invasion. We further investigated the ex-pression of a panel of cancer-related genes and found that BMP9 overexpression increased the phosphorylation of Smad1/5/8 proteins, increased the expression of ID1, and reduced the expression and activity of matrix metalloproteinase 9 (MMP9) in OS cells. BMP9 silencing induced the opposite effects. We also found that BMP9 may not affect the chemokine (C-X-C motif) ligand 12 (CXCL12)/C-X-C chemokine receptor type 4 (CXCR4) axis to regulate the invasiveness and metastatic capacity of OS cells. Interestingly, CXCR4 was expressed in both 143B and MG63 cells, while CXCL12 was only detected in MG63 cells. Taken together, we hypothesize that BMP9 inhibits the migration and invasiveness of OS cells through a Smad-dependent pathway by downregulating the expression and activity of MMP9.

Two new tirucallane triterpenoids from the leaves of Aquilaria sinensis

Jin Tang Cheng,Ya Qiong Han,Juan He,Xing De Wu,Liao Bin Dong,Li Yan Peng,Yan Li,Qin Shi Zhao 대한약학회 2013 Archives of Pharmacal Research Vol.36 No.9

Two new tirucallane triterpenoids, aquilacallanesA–B (1–2), together with 15 known compounds(3–17) were isolated from the leaves of Aquilaria sinensis. The structures of these new compounds were elucidated onthe basis of extensive spectroscopic analyses. All compoundswere evaluated for their cytotoxic activity againstfive human cancer cell lines. The known compounds,ursolic acid (7) and 5,7,40-trimethoxyflavone (14), exhibitedweak cytotoxic activity against some cells.

Lipase Immobilization on Magnetic Microspheres via Spacer Arms: Effect of Steric Hindrance on the Activity

Dong-Hao Zhang,Ya-Qiong Li,Li-Juan Peng,Na Chen 한국생물공학회 2014 Biotechnology and Bioprocess Engineering Vol.19 No.5

Poly(styrene-acrylic acid) magnetic microsphereswith an average diameter of 2 μm were successfullyprepared and used as carriers to immobilize lipase. Lipaseimmobilized on microspheres with no spacer arm exhibitedlow activities, which were attributed to steric hindranceon the lipase conformation. To avoid steric effects,ethylenediamine and poly(ethylene glycol) (PEG) 400/800/4000 were utilized as spacer arms to bind the lipase tothe microspheres. The immobilized lipase activities wereimproved using PEG 800/4000 as a spacer arm. Furthermore,the influence of enzyme loading on lipase activity wasinvestigated, and the results indicated that enzymeoverloading could exert steric effect on lipase activity. Thedegree of PEG modification was demonstrated to affectlipase activity because excess PEG on the surface ofmicrospheres could interact with lipase due to its mobility,consequently reducing lipase activity.

Kinetics of Enzymatic Synthesis of L-ascorbyl Acetate by Lipozyme TLIM and Novozym 435

Dong-Hao Zhang,Ya-Qiong Li,Chao Li,Yv-Qin Lv,Yang-L 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.1

L-ascorbyl acetate was synthesized through lipase-catalyzed esterification using Lipozyme TLIM and Novozym 435. Four solvents, including methanol, ethanol,acetonitrile, and acetone were investigated for the reaction,and acetone and acetonitrile were found to be suitable reaction media. The influences of several parameters such as water activity (aw), substrate molar ratio, enzyme loading,and reaction temperature on esterification of Lascorbic acid were systematically and quantitatively analyzed. Through optimizing the reaction, lipase-catalyzed esterification of L-ascorbic acid gave a maximum conversion of 99%. The results from using Lipozyme TLIM and Novozym 435 as biocatalysts both showed that aw was an important factor for the conversion of L-ascorbic acid. The effect of pH value on lipase-catalyzed L-ascorbic acid esterification in acetone was also investigated. Furthermore,results from a kinetic characterization of Lipozyme TLIM were compared with those for Novozym 435, and suggested that the maximum reaction rate for Lipozyme TLIM was greater than that for Novozym 435, while the enzyme affinity for substrate was greater for Novozym 436.

Biotransformation of natural polyacetylene in red ginseng by Chaetomium globosum

Wang, Bang-Yan,Yang, Xue-Qiong,Hu, Ming,Shi, Li-Jiao,Yin, Hai-Yue,Wu, Ya-Mei,Yang, Ya-Bin,Zhou, Hao,Ding, Zhong-Tao The Korean Society of Ginseng 2020 Journal of Ginseng Research Vol.44 No.6

Background: Fermentation has been shown to improve the biological properties of plants and herbs. Specifically, fermentation causes decomposition and/or biotransformation of active metabolites into high-value products. Polyacetylenes are a class of polyketides with a pleiotropic profile of bioactivity. Methods: Column chromatography was used to isolate compounds, and extensive NMR experiments were used to determine their structures. The transformation of polyacetylene in red ginseng (RG) and the production of cazaldehyde B induced by the extract of RG were identified by TLC and HPLC analyses. Results: A new metabolite was isolated from RG fermented by Chaetomium globosum, and this new metabolite can be obtained by the biotransformation of polyacetylene in RG. Panaxytriol was found to exhibit the highest antifungal activity against C. globosum compared with other major ingredients in RG. The fungus C. globosum cultured in RG extract can metabolize panaxytriol to Metabolite A to survive, with no antifungal activity against itself. Metabolites A and B showed obvious inhibition against NO production, with ratios of 42.75 ± 1.60 and 63.95 ± 1.45% at 50 µM, respectively. A higher inhibitory rate on NO production was observed for Metabolite B than for a positive drug. Conclusion: Metabolite A is a rare example of natural polyacetylene biotransformation by microbial fermentation. This biotransformation only occurred in fermented RG. The extract of RG also stimulated the production of a new natural product, cazaldehyde B, from C. globosum. The lactone in Metabolite A can decrease the cytotoxicity, which was deemed to be the intrinsic activity of polyacetylene in ginseng.

Effects of Myogenin on Expression of Late Muscle Genes through MyoD-Dependent Chromatin Remodeling Ability of Myogenin

Chao Du,Ju-Hua Ni,Ya-Qiong Jin,Jun-Juan Qi,Zhen-Xing Ji,Shu-Yan Li,Guo-Shun An,Hong-Ti Jia 한국분자세포생물학회 2012 Molecules and cells Vol.34 No.2

MyoD and myogenin (Myog) recognize sets of distinct but overlapping target genes and play different roles in skeletal muscle differentiation. MyoD is sufficient for near-full expression of early targets, while Myog can only partially enhance expression of MyoD-initiated late muscle genes. However, the way in which Myog enhances the expression of MyoD-initiated late muscle genes remains unclear. Here, we examine the effects of Myog on chromatin remodeling at late muscle gene promoters and their activation within chromatin environment. Chromatin immunoprecipitation (ChIP) assay showed that Myog selectively bound to the regulatory sequences of late muscle genes. Overexpres-sion of Myog was found to overcome sodium butyrate-inhibited chromatin at late muscle genes in differ-entiating C2C12 myoblasts, shifting the transcriptional activation of these genes to an earlier time period. Furthermore, overexpression of Myog led to increased hyperacetylation of core histone H4 in differentiating C2C12 myoblasts but not NIH3T3 fibroblasts, and hyperacetylated H4 was associated directly with the late muscle genes in differentiating C2C12, indicating that Myog can induce chromatin remodeling in the presence of MyoD. In addition, co-immunopre-cipitation (CoIP) revealed that Myog was associated with the nuclear protein Brd4 in differentiating C2C12 myoblasts. Together, these results suggest that Myog enhances the expression of MyoD-initiated late muscle genes through MyoD-dependent ability of Myog to induce chromatin remodeling, in which Myog-Brd4 interaction may be involved.