Robust and Fast Tracking via Joint Collaborative Representation

Fei Zhou,Guizong Zhang,Xinyue Fan,Dandan Yi 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.4

In this paper, we present a robust and fast tracking method based on joint collaborative representation. Traditional sparse coding based tracking methods code the candidates as a sparse linear combination of a series of object and trivial templates and perform time consuming L1 regularizations. In contrast to these methods, this paper adopts the L2-regularized least square models to reduce the computational complexity. The tracked object can be represented by the linear combination of a series of object templates, and also can be represented by candidate samples in the current frame. We propose a joint objective function to handle the tracking process. In addition, we introduce an effective update scheme to deal with the change of target appearance over time. Experiments on several challenging image sequences show that our proposed tracking method is robust and efficient.

A Novel All-trans Retinoid Acid Derivative N-(3-trifluoromethyl-phenyl)-Retinamide Inhibits Lung Adenocarcinoma A549 Cell Migration through Down-regulating Expression of Myosin Light Chain Kinase

Fan, Ting-Ting,Cheng, Ying,Wang, Yin-Feng,Gui, Shu-Yu,Chen, Fei-Hu,Zhou, Qing,Wang, Yuan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.18

Aim: To observe the effects of a novel all-trans retinoid acid (ATRA) derivative, N-(3-trifluoromethyl-phenyl)-retinamide (ATPR), on lung adenocarcinoma A549 cells and to explore the potential mechanism of ATPR inhibiting of A549 cell migration. Materials and Methods: The cytotoxicity of ATRA and ATPR on A549 cells was assessed using MTT assay. Wound healing assays were used to analyze the influences of ATRA, ATPR, ML-7 (a highly selective inhibitor of myosin light chain kinase (MLCK)), PMA (an activator of MAPKs) and PD98059 (a selective inhibitor of ERK1/2) on the migration of A549 cells. Expression of MLCK and phosphorylation of myosin light chain (MLC) were assessed by Western blotting. Results: ATRA and ATPR inhibited the proliferation of A549 cells in a dose- and time-dependent manner, and the effect of ATPR was much more remarkable compared with ATRA. Relative migration rate and migration distance of A549 cells both decreased significantly after treatment with ATPR or ML-7. The effect on cell migration of PD98059 combining ATPR treatment was more notable than that of ATPR alone. Moreover, compared with control groups, the expression levels of MLCK and phosphorylated MLC in A549 cells were both clearly reduced in ATRA and ATPR groups. Conclusions: ATPR could suppress the migration and invasion of A549 cells, and the mechanism might be concerned with down-regulating the expression of MLCK in the ERK-MAPK signaling pathway, pointing to therapeutic prospects in lung cancer.

The Combined Effect of Sodium Butyrate and Low Culture Temperature on the Production, Sialylation, and Biological Activity of an Antibody Produced in CHO Cells

Fei Chen,Tianci Kou,Li Fan,Yan Zhou,Zhaoyang Ye,Liang Zhao,Wen-Song Tan 한국생물공학회 2011 Biotechnology and Bioprocess Engineering Vol.16 No.6

Cell cultures containing 0 ~ 5 mM sodium butyrate (NaBu) and grown at 30 and 37°C were conducted to investigate the combined effect of NaBu and low temperature on the quantity and quality of an antibody production in CHO cells. Although NaBu addition decreased cell viability by apoptosis in a dose-dependent manner at both 30 and 37°C, the onset of significant apoptosis induced by NaBu was delayed by lowering culture temperature. The highest specific antibody productivity (q_p) of 23.26 pg/cell/day was obtained in the culture containing 2 mM NaBu at 30°C; however, the highest antibody concentration of 167.84 mg/L was achieved in the culture containing 1 mM NaBu at 30°C, as the detrimental effect of further NaBu addition on cell growth compromised its beneficial effect on q_p. Moreover, protein quality with respect to the total sialic acid content and Nglycolylneuraminic acid (Neu5Gc) level was evaluated. There were no apparent changes regarding the total sialic acid content of the antibody, but manipulation of cultures with NaBu treatment or (and) low culture temperature did decrease Neu5Gc levels by 5 ~ 10%. Biological activity of the antibody was also assessed, and no obvious changes were observed. Collectively, the simultaneous application of NaBu and low culture temperature was an effective way to extend culture period and enhance final antibody concentration,without compromising the sialic acid content or biological activity.

Structural Mechanisms of the Cooling Rate Effect on the Deformation Behaviors in Metallic Glasses

Bian Zhou,Ming‑fei Li,Fan Xiong,Liang Yang 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.5

In this work, the structural mechanisms of the cooling rate effect on the deformation behaviors in metallic glasses (MGs) isstudied, by performing the synchrotron radiation-based experiments coupled with a series of simulations. It is found that aMG prepared at lower cooling rate has the higher yield strength and is more likely to soften itself, resulting in lower plasticity.This is because some atomic-to-cluster level structural factors, such as coordination numbers, atomic packing efficiencies,cluster concentrations and regularities. In addition, a quantitative analysis reveals that higher cooling rate leads to more freevolumes, and significantly affect the evolution of free volumes during the compressive deformation, tuning the formationand the evolution of shear transformation zones, as well as the yield strength and the plasticity.

DTSTM: Dynamic Tree Style Trust Measurement Model for Cloud Computing

( Zhen-ji Zhou ),( Li-fa Wu ),( Zheng Hong ),( Ming-fei Xu ),( Fan Pan ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.1

In cloud computing infrastructure, current virtual machine trust measurement methods have many shortcomings in dynamism, security and concurrency. In this paper, we present a new method to measure the trust of virtual machine. Firstly, we propose “behavior trace” to describe the state of virtual machine. Behavior trace is a sequence of behaviors. The measurement of behavior trace is conducted on the basis of anticipated trusted behavior, which not only ensures security of the virtual machine during runtime stage but also reduces complexity of the trust measurement. Based on the behavior trace, we present a Dynamic Tree Style Trust Measurement Model (DTSTM). In this model, the measurement of system domain and user domain is separated, which enhances the extensibility, security and concurrency of the measurement. Finally, based on System Call Interceptor (SCI) and Virtual Machine Introspection (VMI) technology, we implement a DTSTM prototype system for virtual machine trust measurement. Experimental results demonstrate that the system can effectively verify the trust of virtual machine and requires a relatively low performance overhead.

Comparative transcriptome analysis to identify genes involved in terpenoid biosynthesis in Agriophyllum squarrosum, a folk medicinal herb native to Asian temperature deserts

Yin Xiaoyue,Yan-Xia Liu,Qian Chaoju,Zhou Shanshan,Fang Tingzhou,Fan Xingke,Gao yuan,Chang Yuxiao,Yang Jian,Ma Xiao-Fei 한국식물생명공학회 2021 Plant biotechnology reports Vol.15 No.3

Agriophyllum squarrosum is a folk Mongolian medicine with pleiotropic pharmacological and ecological economic importance endemic to Asian temperature deserts. Terpenoids play critical roles in biotic and abiotic stresses due to their antioxidative activities. Based on non-targeted metabolomic analysis, we detected eight terpenoids enriched in the above-ground tissues of A. squarrosum, however, the molecular mechanism underlying terpenoids biosynthesis in this desert medicinal plant is rarely understood. Here, a comparative transcriptome analysis of diferent tissues in A. squarrosum was conducted to identify 84 unigenes encoding key enzymes in the upstream backbone biosynthesis and 53 unigenes encoding the downstream enzymes for terpenoid diversifcation. Most of the upstream genes exhibited signifcant high expression levels in leaf, and some of which were validated by qRT-PCR. Phylogenetic analysis showed that two downstream gene families OSCs (oxidosqualene cyclases) and TPSs (mainly in terpene synthases -g subfamily) had undergone notable gene expansions in A. squarrosum comparing with the other Amaranthaceae plant species and Arabidopsis. Nevertheless, most members from these two gene families showed the tissue-specifc expression in A. squarrosum, which supported the diversifcation and tissue-specifc enrichment of terpenoids across above-ground tissues. Considering to the habitat characteristics of A. squarrosum, we proposed that the enrichment of terpenoids and the functional diversifcation of terpenoids biosynthesis enzymes were more or less involved into its adaptation to stressful environments of deserts. These results expand the available genetic information underlying terpenoid biosynthesis in A. squarrosum, and contribute to deeper researches on pharmaceutical and eco-agricultural applications in this desert medicinal plant.

Sharpened VO₂ Phase Transition via Controlled Release of Epitaxial Strain

Lee, Daesu,Lee, Jaeseong,Song, Kyung,Xue, Fei,Choi, Si-Young,Ma, Yanjun,Podkaminer, Jacob,Liu, Dong,Liu, Shih-Chia,Chung, Bongwook,Fan, Wenjuan,Cho, Sang June,Zhou, Weidong,Lee, Jaichan,Chen, Long-Qin American Chemical Society 2017 NANO LETTERS Vol.17 No.9

<P>Phase transitions in correlated materials can be manipulated at the nanoscale to yield emergent functional properties, promising new paradigms for nanoelectronics and nanophotonics. Vanadium dioxide (VO2), an archetypal correlated material, exhibits a metal insulator transition (MIT) above room temperature. At the thicknesses required for heterostructure applications, such as an optical modulator discussed here, the strain state of VO2 largely determines the MIT dynamics critical to the device performance. We develop an approach to control the MIT dynamics in epitaxial VO2 films by employing an intermediate template layer with large lattice mismatch to relieve the interfacial lattice constraints, contrary to conventional thin film epitaxy that favors lattice match between the substrate and the growing film. A combination of phase-field simulation, in situ real-time nanoscale imaging, and electrical measurements reveals robust undisturbed MIT dynamics even at preexisting structural domain boundaries and significantly sharpened MIT in the templated VO2 films. Utilizing the sharp MIT, we demonstrate a fast, electrically switchable optical waveguide. This study offers unconventional design principles for heteroepitaxial correlated materials, as well as novel insight into their nanoscale phase transitions.</P>

Identifying Typhoon Targeted Observations Sensitive Areas Using the Gradient Definition Based Method

Bin Mu,Juhui Ren,Shi-Jin Yuan,Fei-Fan Zhou 한국기상학회 2019 Asia-Pacific Journal of Atmospheric Sciences Vol.55 No.2

Increasing additional observation in the typhoon targeted observation sensitive area can help providing more accurate initial field for numerical models, further to improve the typhoon forecast skill. The critical problem is how to identify the typhoon targeted observation sensitive area. Conditional nonlinear optimal perturbation (CNOP) has been proved to be an effective method. Generally, the CNOP is solved using adjoint-based method, which needs to utilize the adjoint models of the numerical models. However, the adjoint models for some numerical models have not been developed or only for some modules. The gradient definition based method is an adjoint-free method, which has been applied to solve the CNOP of Zebiak-Cane (ZC) model with 1080-dimensional solution space to study the optimal precursors of El Nino-Southern Oscillation (ENSO) event. It is very easy to realize, but the time efficiency will go down dramatically along with the rapidly increasing dimensions. In this paper, the gradient definition based method is applied to solve the CNOP ofMM5 model with more than 105-dimensional solution space to identify the typhoon targeted observation sensitive area. Compared to the adjoint-based method, the identified sensitive area and the benefits of the CNOPs are very similar for typhoon Matmo (2014) and Fitow (2013), and higher time efficiency can be achieved. Furthermore, the OSSEs’ results show that the sensitive area identified can be used to improve the forecast skill of typhoon Matmo and Fitow to different extent.

Dynamic Characteristics of Saturated Soft Clays under Cyclic Loading in Drained Condition

Yong-hong Miao,Ruo-Yu Sheng,Jie Yin,Fan-Bo Zhou,Jian-fei Lu 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.2

This study presents an experimental investigation on the effects of cyclic loading waveform and cyclic stress ratio (CSR) on dynamic behaviors through laboratory tests on a source of soft clay under cyclic loading in drained condition. Test results showed that under different cyclic loading waveforms at a given frequency (f = 1 Hz) and CSR = 0.6, the axial strain increases significantly at a relatively lower number of cycles (N) and then became stable, while the axial strain consistently decreases with the increasing N and tend to be stable. At a given N, specimen under sine wave cyclic loads shows a higher axial strain rate than that under triangle wave or square cyclic loads. Test results also indicated that at different CSRs, the axial strain increases rapidly at a relatively lower N and then gradually tends to be stable with the increasing N at lower CSR yet there is no stable trend for specimens at higher CSR, which indicates there is a critical value of CSR. It is recommended to apply the cyclic loading in sine waveform with CSR close to and less than the critical value to get a better treatment effect.

CNOP-Based Sensitive Areas Identification for Tropical Cyclone Adaptive Observations with PCAGA Method

Lin-Lin Zhang,Shi-Jin Yuan,Bin Mu,Fei-Fan Zhou 한국기상학회 2017 Asia-Pacific Journal of Atmospheric Sciences Vol.53 No.1

In this paper, conditional nonlinear optimal perturbation (CNOP) was investigated to identify sensitive areas for tropical cyclone adaptive observations with principal component analysis based genetic algorithm (PCAGA) method and two tropical cyclones, Fitow (2013) and Matmo (2014), were studied with a 120 km resolution using the fifth-generation Mesoscale Model (MM5). To verify the effectiveness of PCAGA method, CNOPs were also calculated by an adjoint-based method as a benchmark for comparison on patterns, energies, and vertical distributions of temperatures. Comparing with the benchmark, the CNOPs obtained from PCAGA had similar patterns for Fitow and a little different for Matmo; the vertically integrated energies were located closer to the verification areas and the initial tropical cyclones. Experimental results also presented that the CNOPs of PCAGA had a more positive impact on the forecast improvement, which gained from the reductions of the CNOPs in the whole domain containing sensitive areas. Furthermore, the PCAGA program was executed 40 times for each case and all the averages of benefits were larger than the benchmark. This also proved the validity and stability of the PCAGA method. All results showed that the PCAGA method could approximately solve CNOP of complicated models without computing adjoint models, and obtain more benefits of reducing the CNOPs in the whole domain.