Adaptive Robust Control of 5 DOF Upper-limb Exoskeleton Robot

Hao-Bo Kang,Jian-Hui Wang 제어·로봇·시스템학회 2015 International Journal of Control, Automation, and Vol.13 No.3

This paper deals with the problem of robust output feedback control for a class of 5DOF upper-limb exoskeleton robot. It is able to assist with shoulder, elbow and wrist joint movements. Robustness is assured for the proposed controller in the presence of model uncertainties. Ultimate boundedness is proved for the presented adaptive observer-based controller. The other advantage of the proposed method is that the implemented information for feedback is only the measurement of position. The estimation of velocity and acceleration is provided by an adaptive observer without additional sensors. By utilizing a novel adaptive logic-based switching control scheme, a trajectory tracking performance is well achieved with a tunable error bound. The simulation example also verifies the effectiveness of the proposed control scheme.

Growth of Human Colon Cancer Cells in Nude Mice is Delayed by Ketogenic Diet With or Without Omega-3 Fatty Acids and Medium-chain Triglycerides

Hao, Guang-Wei,Chen, Yu-Sheng,He, De-Ming,Wang, Hai-Yu,Wu, Guo-Hao,Zhang, Bo Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.5

Background: Tumors are largely unable to metabolize ketone bodies for energy due to various deficiencies in one or both of the key mitochondrial enzymes, which may provide a rationale for therapeutic strategies that inhibit tumor growth by administration of a ketogenic diet with average protein but low in carbohydrates and high in fat. Materials and Methods: Thirty-six male BALB/C nude mice were injected subcutaneously with tumor cells of the colon cancer cell line HCT116. The animals were then randomly split into three feeding groups and fed either a ketogenic diet rich in omega-3 fatty acids and MCT (MKD group; n=12) or lard only (LKD group; n=12) or a standard diet (SD group; n=12) ad libitum. Experiments were ended upon attainment of the target tumor volume of $600mm^3$ to $700mm^3$. The three diets were compared for tumor growth and survival time (interval between tumor cell injection and attainment of target tumor volume). Results: The tumor growth in the MKD and LKD groups was significantly delayed compared to that in the SD group. Conclusions: Application of an unrestricted ketogenic diet delayed tumor growth in a mouse xenograft model. Further studies are needed to address the mechanism of this diet intervention and the impact on other tumor-relevant parameters such as invasion and metastasis.

영화의 감정을 표현하는데 있어서 특수효과의 역할에 대한 연구

개호박(Gai hao-bo) 한국콘텐츠학회 2013 한국콘텐츠학회 종합학술대회 논문집 Vol.2013 No.5

Optimum Design of a Damping Plate with an Unconstrained Viscoelastic Damping Layer Using Combined Genetic Algorithm

Bo Suk Yang,Byung Gun Choi,Young Hun Yu,Hao Tai Nan 대한기계학회 1999 KSME International Journal Vol.13 No.5

Application of Iterative Singular Value Decomposition De-noising to Centrifugal Compressor Signal Analysis

Hao Wang,Jinji Gao,Zhinong Jiang,Bo Ma 보안공학연구지원센터 2012 International Journal of Hybrid Information Techno Vol.5 No.4

A Comparison of the Lookup Table and On-The-Fly Calculation Methods for the Beamforming Control Unit

Bo Yang,Jia Hao Cheong,Yvonne Ying Hung Lam,Lian Soon Ng 대한전자공학회 2008 ITC-CSCC :International Technical Conference on Ci Vol.2008 No.7

Modern diagnostic ultrasound beamformers require extensive delay information for the focusing of each focal point along the image lines. For a typical beamforming system with dynamic delays, the beamforming control unit is used to calculate the delay information and generate instant delay profiles in order to achieve dynamic focusing beamforming. In this study, the beamforming control unit targeted at a home-based portable delta-sigma oversampled ultrasound beamforming setup was developed. The beamforming principle for 1-D linear transducer array with dynamic aperture was exploited, and three delay generation methods including complete lookup table, compressed lookup table with delta encoding and general parametric algorithm were investigated, implemented and synthesized using VHDL for a FPGA device Spartan-3E XC3S500E. A comparison was performed among the three delay generation methods on their performances in terms of overall logic resource usage and power consumption.

Development of a strategy for the screening of α-glucosidase-producing microorganisms

Bo Zhou,Nan Huang,Wei Zeng,Hao Zhang,Guiguang Chen,Zhiqun Liang 한국미생물학회 2020 The journal of microbiology Vol.58 No.2

α-Glucosidase is a crucial enzyme for the production of isomaltooligosaccharide. In this study, a novel method comprising eosin Y (EY) and α-D-methylglucoside (AMG) in glass plates was tested for the primary screening of α-glucosidaseproducing strains. First, α-glucosidase-producing Aspergillus niger strains were selected on plates containing EY and AMG based on transparent zone formation resulting from the solubilization of EY by the hydrolyzed product. Conventional methods that use trypan blue (TB) and p-nitrophenyl-α-Dglucopyranoside (pPNP) as indicators were then compared with the new strategy. The results showed that EY-containing plates provide the advantages of low price and higher specificity for the screening of α-glucosidase-producing strains. We then evaluated the correlation between the hydrolytic activity of α-glucosidase and diffusion distance, and found that good linearity could be established within a 6–75 U/ml enzyme concentration range. Finally, the hydrolytic and transglycosylation activities of α-glucosidase obtained from the target isolates were determined by EY plate assay and 3,5- dinitrosalicylic acid-Saccharomyces cerevisiae assay, respectively. The results showed that the diameter of the transparent zone varied among isolates was positively correlated with α-glucosidase hydrolytic activity, while good linearity could also be established between α-glucosidase transglycosylation activity and non-fermentable reducing sugars content. With this strategy, 7 Aspergillus niger mutants with high yield of α-glucosidase from 200 obvious single colonies on the primary screen plate were obtained.

Effect of Pre-straining and Subsequent Annealing on Microstructure and Mechanical Property of Zr–Sn–Nb–Fe Zirconium Alloy

Hao Wang,Dianwu Zhou,Youruiling Yan,Jinshui Liu,Bo Gao 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.3

Zirconium alloy is extensively used in nuclear industries as cladding and core structural material. However, the formabilityand service behavior are affected due to the anisotropy of mechanical property, which is detrimental to the specific application. In this work, effect of pre-straining and subsequent annealing (PA) on microstructure and mechanical property ofZr–Sn–Nb–Fe zirconium alloy is determined by means of scanning electron microscope equipped with electron backscattersdiffraction and digital image correlation technique. It is found that the basal texture intensity and grain size of as-receivedsample decreases after pre-straining, the work-hardening value (n) increases from 0.126 of as-received sample to 0.152 ofPA samples, while the anisotropy of mechanical property decreases gradually with the increase of pre-straining level. Inaddition, the strength, ductility and work-hardening value (n) of the PA samples tend to be accordant in the transverse direction,rolling direction (RD) and the 45° direction when the pre-straining level reaches 8%. The basal texture is graduallyweakened and dispersed along the RD after annealing, whose orientation is favorable for the activation of pyramidal ⟨c + a⟩slip to accommodate to the strain in thickness direction, which leads to the lower anisotropy (featured by the r-value). Thelow r-value and high work-hardening value (n) are favorable for improving formability. Hence, microstructure and textureof zirconium alloy can be modified though appropriate PA process to improve the comprehensive properties.

Comprehensive analysis of the prognostic value and immune implications of the TTK gene in lung adenocarcinoma: a meta-analysis and bioinformatics analysis

Bo Li,Xiaojuan Gu,Hanbing Zhang,Hao Xiong 한국통합생물학회 2022 Animal cells and systems Vol.26 No.3

Background: High expression levels of the TTK gene are closely related to tumor occurrence and poor prognosis, as confirmed by some studies. Our study explored the prognosis of lung adenocarcinoma (LUAD) patients with different TTK levels and the possible pathological mechanism of TTK in LUAD. Methods: We extensively searched literature databases and high-throughput sequencing databases and included relevant literature or datasets in the meta-analysis according to the inclusion and exclusion criteria. Hazard ratios (HRs) and 95% confidence intervals (CIs) related to TTK expression were calculated, publication bias was assessed, and sensitivity tests were performed. We also compared the relationship between cancer immune infiltrating cells and tumor mutation burden (TMB) in patients with different TTK expression levels via bioinformatics analysis. The half maximal inhibitory concentration (IC50) of some chemotherapeutic and targeted therapy drugs were calculated. The potential biological functions or pathways associated with different TTK expression levels were determined by gene set enrichment analysis (GSEA). Results: The meta-analysis revealed that higher TTK expression level was significantly associated with poor prognosis in LUAD patients, both in overall survival (OS) and progression-free survival (PFS). The expression level of TTK was significantly correlated with presence of some immune cells and TMB. Tumors with higher TTK expression levels were mostly enriched for the cell cycle, DNA replication and homologous recombination pathways. In addition, patients with different TTK expression levels were differently sensitive to some antitumor drugs. Conclusion: TTK may be a promising prognostic biomarker for LUAD and is worthy of further investigation.

Aerodynamic Performance Enhancement of Tiltrotor Aircraft Wings Using Double-Row Vortex Generators

Hao Chen,Bo Chen 한국항공우주학회 2021 International Journal of Aeronautical and Space Sc Vol.22 No.4

To improve the aerodynamic performance of tiltrotor aircraft, the flow characteristics of the V-22 airfoil without and with one, two parallel rows of vortex generators (VGs) were investigated using numerical simulation methods. The results were obtained with three-dimensional compressible Reynolds-averaged Navier–Stokes equations, and the turbulence was simulated with the SA-based DES model. The influence of the chordwise installation of VGs was emphatically discussed. First, the single-row VGs are, respectively, mounted at the 10, 20, and 40% chord positions, denoted as VGs1, VGs2, and VGs3. The results indicate that with the addition of the optimal configuration (VGs1), the maximum lift coefficient is extended from 1.43 to 2.44, and the stall angle of attack increases from 10° to 22° with respect to the clean airfoil. The drag coefficient of the airfoil with VGs1 is 60.8% lower than that of the airfoil without VGs at an angle of attack of 24°. On this basis, the double-row VGs’ arrangements are located at the 10 and 30% chord positions (VGs4), the 10 and 50% chord positions (VGs5) and the 10 and 70% chord positions (VGs6). Compared to single-row VGs, double-row VGs have the greater potential to suppress the flow separation. Due to the effect of VGs4, the maximum value of lift coefficient has increased to 2.61. However, the case of VGs6 degrades the overall aerodynamic performance as compared to VGs1. Further research suggest that with the increase in the height of the second row of vortex generators (VGs7), the aerodynamic characteristics of airfoil A821201 can be effectively enhanced at large angles of attack.