Crowded Pedestrian Detection and Density Estimation by Visual Words Analysis

Shilin Zhang,Xunyuan Zhang 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.3

Crowded pedestrian detection and density estimation are very useful and important under transportation environment. In this paper, we present a novel method for crowded pedestrian detection and density estimation through a weighting scheme of bag of visual words model which characterizes both the weight and the relative spatial arrangement aspects of visual words in depicting an image. Firstly, we analyze the visual words generation process. We give each visual word a weight by counting the number of images through which each visual word is clustered and computing the cluster radius of each visual word. To be more specifically, the co-occurrences of visual words are computed with respect to spatial predicates over a hierarchical spatial partitioning of an image. We validate this method using a challenging ground truth pedestrian dataset Pascal VOC 2007. Our approach is shown to be more accuracy than a non-weighting bag-of-visual-words one. The algorithm’s cost is also more efficient than the competing pairs.

Locate and Detect Persons in Crowded Scenes Aided by Objectiveness Measure

Shilin Zhang,Xunyuan Zhang 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.6

Locating persons in crowded scenes is very difficult due to multi-resolution and complex environment. The other difficulty in pedestrian detection domain is the real time requirement, because the camera installed on the crossing road is in high definition. In this paper, we presented a multi-task pedestrian detection framework boosted by Bing feature. We firstly trained upright full-body, multi-person, half-body and head models, then we compute the object-ness score and generate 1000 proposals by Bing feature, and at last we apply different model to different aspect ratio of the detection proposals. The experiment results on the PASCAL VOC 2007 show that our method outperforms all the other methods and achieved lower miss rate than the state-of-the-art. The computation time cost is just the half of state-of-the-art method.

Cloning, Expression, and Characterization of Xylose Reductase with Higher Activity from Candida tropicalis

Feiwei Zhang,Dairong Qiao,Hui Xu,Chong Liao,Shilin Li,Yi Cao 한국미생물학회 2009 The journal of microbiology Vol.47 No.3

Xylose reductase (XR) is a key enzyme in xylose metabolism because it catalyzes the reduction of xylose to xylitol. In order to study the characteristics of XR from Candida tropicalis SCTCC 300249, its XR gene (xyl1) was cloned and expressed in Escherichia coli BL21 (DE3). The fusion protein was purified effectively by Ni2+-chelating chromatography, and the kinetics of the recombinant XR was investigated. The Km values of the C. tropicalis XR for NADPH and NADH were 45.5 µM and 161.9 µM, respectively, which demonstrated that this XR had dual coenzyme specificity. Moreover, this XR showed the highest catalytic efficiency (kcat=1.44×104 min-1) for xylose among the characterized aldose reductases. Batch fermentation was performed with Saccharomyces serivisiae W303-1A:pYES2XR, and resulted in 7.63 g/L cell mass, 93.67 g/L xylitol, and 2.34 g/L·h xylitol productivity. This XR coupled with its dual coenzyme specificity, high activity, and catalytic efficiency proved its utility in in vitro xylitol production.

The growth improvement of DvGS2-transgenic Arabidopsis thaliana arises from the higher efficiency of nitrogen and carbon assimilation

Chenguang Zhu,Shilin Chen,Guimin Zhang,Wei Wang,Yuanping Tang,Bing Mei,Rentao Song 한국식물생명공학회 2015 Plant biotechnology reports Vol.9 No.4

The overexpression of algal glutamine synthetase (GS) gene DvGS2 in Arabidopsis thaliana resulted in higher plant biomass and better growth phenotype. The purpose of this study was to understand the biological mechanism for the improvement of growth phenotype of DvGS2-transgenic Arabidopsis. A series of molecular and biochemical investigation related to nitrogen and carbon metabolism in DvGS2-transgenic line was, respectively, conducted. Analysis of nitrogen use efficiency (NUE)-related gene expression and enzymatic activity revealed that the transcriptional level and enzymatic activity of genes encoding glutamate synthase, glutamate dehydrogenase and alanine aminotransferase were significantly up-regulated especially under low nitrate condition. The DvGS2- transgenic line showed higher total nitrogen content and lower carbon: nitrogen ratio than the wild type. Significant reduced concentration of leaf free ammonium, higher concentrations of total amino acids, individual amino acid (glutamine, methionine, alanine, asparagine) together with increased concentrations of glucose, fructose and starch, confirmed the higher efficiency of nitrogen and carbon assimilation. These improved metabolisms of nitrogen and carbon conferred the DvGS2-transgenic Arabidopsis more biomass, better growth phenotype and higher NUE compared with the wild type plant.

Comparison Study of Long-haul 100-Gb/s DDO-OFDM and CO-OFDM WDM Systems

Ling Liu,Shilin Xiao,Meihua Bi,Lu Zhang 한국광학회 2016 Current Optics and Photonics Vol.20 No.5

In this paper, for the first time, the transmission performances of long-haul 100-Gb/s direct detectionoptical OFDM (DDO-OFDM) and coherent optical OFDM (CO-OFDM) wavelength division multiplexing(WDM) systems are compared by simulation. It provides specific guides for system parameter selectionto get a high-performance and cost-effective OFDM WDM system. Specifically, the comparison involvesthree aspects: launched power is investigated to achieve better system performance; laser linewidth isnumerically investigated to choose cost-effective laser; system dispersion tolerances with different laserlinewidths are analyzed to further reveal the advantages and disadvantages of these two detecting methods,direct detection and coherent detection, in long-haul OFDM WDM system.

Physiological and omics analysis of maize inbred lines during late grain development

Jin Xining,Zhai Huijie,Wang Pingxi,Zhang Xiaoxiang,Wu Xiangyuan,Zhang Huaisheng,Chen Shilin,Huang Zhongwen 한국유전학회 2022 Genes & Genomics Vol.44 No.8

Background: There were significant differences in the change of moisture content and grain composition at the late stage of grain development among different maize varieties, but the regulation mechanism is not clear. Objective: To explore the key genes causing the variation in physiological traits of two typical maize inbred lines in late grain development. Methods: The grains at different development stages were selected as materials to determine the content of water, sucrose, starch and ABA. Transcriptomic and proteomic analysis of the materials were performed to screen relevant genes. Results: The grain dehydration rate and the content of sucrose, starch and ABA were showed significant differences between two varieties in the late stage of grain development. The enrichment analysis of common differentially expressed genes (proteins) showed that most of the genes (proteins) were enriched in the extracellular region. The downregulated genes were mainly concentrated in carbohydrate metabolism and lipid metabolism, while the upregulated genes were mainly in response to stress. Furthermore, this study also identified many key candidate genes (dehydrin genes, pathogenesis-related genes, sucrose synthase and secondary metabolites related genes) related to late grain development of maize. Conclusions: The suggested genes related to late grain development of maize can be candidates for further functional study.

Metabolomes and transcriptomes revealed the saponin distribution in root tissues of Panax quinquefolius and Panax notoginseng

Wei, Guangfei,Yang, Feng,Wei, Fugang,Zhang, Lianjuan,Gao, Ying,Qian, Jun,Chen, Zhongjian,Jia, Zhengwei,Wang, Yong,Su, He,Dong, Linlin,Xu, Jiang,Chen, Shilin The Korean Society of Ginseng 2020 Journal of Ginseng Research Vol.44 No.6

Background: Panax quinquefolius and Panax notoginseng are widely used and well known for their pharmacological effects. As main pharmacological components, saponins have different distribution patterns in the root tissues of Panax plants. Methods: In this study, the representative ginsenosides were detected and quantified by desorption electrospray ionization mass spectrometry and high-performance liquid chromatography analysis to demonstrate saponin distribution in the root tissues of P. quinquefolius and P. notoginseng, and saponin metabolite profiles were analyzed by metabolomes to obtain the biomarkers of different root tissues. Finally, the transcriptome analysis was performed to demonstrate the molecular mechanisms of saponin distribution by gene profiles. Results: There was saponin distribution in the root tissues differed between P. quinquefolius and P. notoginseng. Eight-eight and 24 potential biomarkers were detected by metabolome analysis, and a total of 340 and 122 transcripts involved in saponin synthesis that were positively correlated with the saponin contents (R > 0.6, P < 0.05) in the root tissues of P. quinquefolius and P. notoginseng, respectively. Among them, GDPS1, CYP51, CYP64, and UGT11 were significantly correlated with the contents of Rg1, Re, Rc, Rb2, and Rd in P. quinquefolius. UGT255 was markedly related to the content of R1; CYP74, CYP89, CYP100, CYP103, CYP109, and UGT190 were markedly correlated with the Rd content in P. notoginseng.