IoT기반 헬스케어 사용자 경험가치가 사용량과 지속적 사용의도에 미치는 영향에 관한연구 -중국내 샤오미 미밴드 사용자를 중심으로-

상맹 ( Shang Meng ),신용호 ( Shin Yong Ho ),이철우 ( Lee Chul Woo ) 한국품질경영학회 2016 품질경영학회지 Vol.44 No.3

Purpose: This study identifies causality in IoT-based healthcare user’s experience(playful experience, economical experience), trust, usage, degree of dependence and continuous use intention, especially focused on chinese case. Methods: Face to face interviews was conducted for people who has experience in the use of the Xiaomi Mi band. This study used Partial Least Square(PLS) method with the questionnaires from the interview. Results: IoT-based healthcare users taking playful experience have a strong trust in a positive economic experiences. Also, the user recognizing the experience as an economic one shows stronger intention to use continuously. Conclusion: By getting healthcare users have more economic experience, they have continuous use intention of healthcare product. The empirical findings can be applied to the related companies strategy building.

Modeling and control strategy of flexible joint servo system in humanoid manipulator driven by tendon-sheath

Meng Yin,Dongyang Shang,Binhua Huang,Xinyu Wu,Wei Feng 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.5

The control effect of rotational speed in joints directly affects the motion accuracy of a humanoid manipulator driven by tendon-sheath. The dynamic parameters of the joint have time-varying characteristics due to the posture change of the manipulator. The joint driven by tendon-sheath has a specific torsional stiffness, so flexibility should be considered in the humanoid manipulator’s servo system. The time-varying of the parameters in the servo system and the joint flexibility can cause fluctuation of the output speed. To improve the motion accuracy of the humanoid manipulator, a fuzzy-tuned PI control strategy is used to suppress the instability of the output speed. First, the change law of the inertia on the motor side of the flexible joint is calculated by the dynamics equation of the humanoid manipulator. Next, a mathematical model of the joint is established, and the transfer function from the load speed to the electromagnetic torque is obtained. Furthermore, according to the pole-placement strategy, the fuzzy-tuned PI controller parameters are selected appropriately for the manipulator in different postures. Finally, the effectiveness of the proposed method is verified by numerical simulations and control experiments of the manipulator. The results show that the fuzzy-tuned PI control strategy can significantly reduce the tracking errors and improve the control performance of the manipulator.

Characteristics and source apportionment of fine haze aerosol in Beijing during the winter of 2013

Shang, Xiaona,Zhang, Kai,Meng, Fan,Wang, Shihao,Lee, Meehye,Suh, Inseon,Kim, Daigon,Jeon, Kwonho,Park, Hyunju,Wang, Xuezhong,Zhao, Yuxi Copernicus GmbH 2018 Atmospheric Chemistry and Physics Vol.18 No.4

<P>Abstract. For PM2.5 filter samples collected daily at the Chinese Research Academy of Environmental Sciences (Beijing, China) from December of 2013 to February of 2014 (the winter period), chemical characteristics and sources were investigated with an emphasis on haze events in different alert levels. During the 3 months, the average PM2.5 concentration was 89 µg m−3, exceeding the Chinese national standard of 75 µg m−3 in 24 h. The maximum PM2.5 concentration was 307 µg m−3, which characterizes developed-type pollution (PM2.5 / PM10>0.5) in the World Health Organization criteria. PM2.5 was dominated by SO42−, NO3−, and pseudo-carbonaceous compounds with obvious differences in concentrations and proportions between non-haze and haze episodes. The non-negative matrix factorization (NMF) analysis provided reasonable PM2.5 source profiles, by which five sources were identified: soil dust, traffic emission, biomass combustion, industrial emission, and coal combustion accounting for 13, 22, 12, 28, and 25 % of the total, respectively. The dust impact increased with northwesterlies during non-haze periods and decreased under stagnant conditions during haze periods. A blue alert of heavy air pollution was characterized by the greatest contribution from industrial emissions (61 %). During the Chinese Lantern Festival, an orange alert was issued and biomass combustion was found to be the major source owing to firework explosions. Red-alert haze was almost equally contributed by local traffic and transported coal combustion emissions from the vicinity of Beijing (approximately 40 % each) that was distinguished by the highest levels of NO3− and SO42−, respectively. This study also reveals that the severity and source of haze are largely dependent on meteorological conditions. </P>

Automatic modulation classification of noise‐like radar intrapulse signals using cascade classifier

Xianpeng Meng,Chaoxuan Shang,Jian Dong,Xiongjun Fu,Ping Lang 한국전자통신연구원 2021 ETRI Journal Vol.43 No.6

Automatic modulation classification is essential in radar emitter identification. We propose a cascade classifier by combining a support vector machine (SVM) and convolutional neural network (CNN), considering that noise might be taken as radar signals. First, the SVM distinguishes noise signals by the main ridge slice feature of signals. Second, the complex envelope features of the predicted radar signals are extracted and placed into a designed CNN, where a modulation classification task is performed. Simulation results show that the SVM‐CNN can effectively distinguish radar signals from noise. The overall probability of successful recognition (PSR) of modulation is 98.52% at 20 dB and 82.27% at −2 dB with low computation costs. Furthermore, we found that the accuracy of intermediate frequency estimation significantly affects the PSR. This study shows the possibility of training a classifier using complex envelope features. What the proposed CNN has learned can be interpreted as an equivalent matched filter consisting of a series of small filters that can provide different responses determined by envelope features.

Finite element simulation of unconstraint vibration treatment for fatigued copper film

Hai-Meng Zhang,De-Guang Shang,Shuai Lv,Xiao-Dong Liu,Yu Zhang 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.9

In this paper, in order to investigate the residual strain relief in the fatigued copper film with a thickness of 33 μm, an unconstraint vibration treatment process was simulated by finite element (FE) method. The experimental processes, including fatigue and unconstraint vibration processes, were simulated. The fatigue process for the original specimen and the vibration process for the damaged specimen were analyzed by the static and transient dynamic analysis, respectively. The simulation results showed that the unconstraint vibration treatment can lead to the residual strain of the fatigued copper film to be reduced and redistributed. The effect of the vibration parameters on the treatment effectiveness was analyzed by the different fatigue experiments and unconstraint vibration treatments, and the results showed that the FE simulation results are in agreement with the experimental observations.

Trifluoroethanol-induced changes in activity and conformation of manganese-containing superoxide dismutase.

Yin, Shang-Jun,L?, Zhi-Rong,Park, Daeui,Chung, Hae Young,Yang, Jun-Mo,Zhou, Hai-Meng,Qian, Guo-Ying,Park, Yong-Doo Humana Press 2012 Applied biochemistry and biotechnology Vol.166 No.2

<P>Superoxide dismutase (SOD, EC 1.15.1.1) plays an important role in antioxidant defense in organisms exposed to oxygen. However, there is a lack of research into the regulation of SOD activity and structural changes during folding, especially for SOD originating from extremophiles. We studied the inhibitory effects of trifluoroethanol (TFE) on the activity and conformation of manganese-containing SOD (Mn-SOD) from Thermus thermophilus. TFE decreased the degree of secondary structure of Mn-SOD, which directly resulted in enzyme inactivation and disrupted the tertiary structure of Mn-SOD. The kinetic studies showed that TFE-induced inactivation of Mn-SOD is a first-order reaction and that the regional Mn-contained active site is very stable compared to the overall structure. We further simulated the docking between Mn-SOD and TFE (binding energy for Dock 6.3, -9.68 kcal/mol) and predicted that the LEU9, TYR13, and HIS29 residues outside of the active site interact with TFE. Our results provide insight into the inactivation of Mn-SOD during unfolding in the presence of TFE and allow us to describe ligand binding via inhibition kinetics combined with computational predictions.</P>

Vibration Suppression Method Based on PI Fuzzy Controller Containing Disturbance Observe for Dual-flexible Manipulator with an Axially Translating Arm

Dongyang Shang,Xiaopeng Li,Fanjie Li,Meng Yin 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.5

A dual-flexible manipulator with an axially translating arm is composed of a motor, a flexible joint, and a flexible load that can be telescopic. The friction torque at the motor, the time-varying characteristics of load parameters, as well as the flexibility of joints and loads will cause the vibration of the manipulator. Transverse vibration will affect the movement accuracy of the end-effector. In this paper, a fuzzy adaptive PI control strategy containing disturbance observers (DOB) is used to reduce the fluctuation of the servo system’s output speed, thereby suppressing the vibration of the manipulator. Firstly, the dynamical model of the dual-flexible manipulator considering the friction torque is established. Then, the low-pass filter in the DOB is designed, and the PI controller parameters are adjusted in real-time by the fuzzy adaptive control strategy. Finally, the numerical simulation analysis and experiments of the dual-flexible manipulator are carried out. The simulation and experimental results show that; 1) The DOB can effectively eliminate the influence of friction torque; 2) The control strategy can reduce the output speed error. Therefore, the control strategy proposed in this paper can effectively reduce the vibration of the dual-flexible manipulator with an axially translating arm to improve the movement accuracy of the end-effector.

Luteolin Inhibits Proliferation Induced by IGF-1 Pathway Dependent ERα in Human Breast Cancer MCF-7 Cells

Wang, Li-Meng,Xie, Kun-Peng,Huo, Hong-Nan,Shang, Fei,Zou, Wei,Xie, Ming-Jie Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.4

The growth of many breast tumors is stimulated by IGF-1, which activates signal transduction pathways inducing cell proliferation. $ER{\alpha}$ is important in this process. The aim of the study was to investigate relationships in vitro among inhibitory effects of luteolin on the growth of MCF-7 cells, IGF-1 pathway and $ER{\alpha}$. Our results showed that luteolin could effectively block IGF-l-stimulated MCF-7 cell proliferation in a dose- and time-dependent manner and block cell cycle progression and induce apoptosis evidenced by the flow cytometric detection of sub-G1DNA content. Luteolin markedly decreased IGF-l-dependent IGF-IR and Akt phosphorylation without affecting Erk1/2 phosphorylation. Further experiments pointed out that $ER{\alpha}$ was directly involved in IGF-l induced cell growth inhibitory effects of luteolin, which significantly decreased $ER{\alpha}$ expression. Knockdown of $ER{\alpha}$ in MCF-7 cells by an $ER{\alpha}$-specific siRNA decreased the IGF-l induced cell growth inhibitory effects of luteolin. $ER{\alpha}$ is thus a possible target of luteolin. These findings indicate that the inhibitory effect of luteolin on the growth of MCF-7 cells is via inhibiting IGF-l mediated PI3K-Akt pathway dependent of $ER{\alpha}$ expression.

Biological Characteristics of Recombinant Arthrobotrys oligospora Chitinase AO-801

Gong, Shasha,Meng, Qingling,Qiao, Jun,Huang, Yunfu,Zhong, Wenqiang,Zhang, Guowu,Zhang, Kai,Li, Ningxing,Shang, Yunxia,Li, Zhiyuan,Cai, Xuepeng The Korea Society for Parasitology and Tropical Me 2022 The Korean Journal of Parasitology Vol.60 No.5

Chitinase AO-801 is a hydrolase secreted by Arthrobotrys oligospora during nematode feeding, while its role remained elusive. This study analyzed the molecular characteristics of recombinant chitinase of Arthrobotrys oligospora (reAO-801). AO-801 belongs to the typical glycoside hydrolase 18 family with conserved chitinase sequence and tertiary structure of (α/β)₈ triose-phosphate isomerase (TIM) barrel. The molecular weight of reAO-801 was 42 kDa. reAO-801 effectively degraded colloidal and powdered chitin, egg lysate, and stage I larval lysate of Caenorhabditis elegans. The activity of reAO-801 reached its peak at 40℃ and pH values between 4-7. Enzyme activity was inhibited by Zn2⁺, Ca2⁺, and Fe3⁺, whereas Mg2⁺ and K⁺ potentiated its activity. In addition, urea, sodium dodecyl sulfate, and 2-mercaptoethanol significantly inhibited enzyme activity. reAO-801 showed complete nematicidal activity against C. elegans stage I larvae. reAO-801 broke down the C. elegans egg shells, causing them to die or die prematurely by hatching the eggs. It also invoked degradation of Haemonchus contortus eggs, resulting in apparent changes in the morphological structure. This study demonstrated the cytotoxic effect of reAO-801, which laid the foundation for further dissecting the mechanism of nematode infestation by A. oligospora.

Hepatoprotective effects of loach (Misgurnus anguillicaudatus) lyophilized powder on dimethylnitrosamine-induced liver fibrosis in rats

Qian Zhang,Meng-Meng Shang,Qu-Fei Ling,Xiao-Ping Wu,Chun-Yu Liu 대한약학회 2021 Archives of Pharmacal Research Vol.44 No.8

This study investigates the hepatoprotectiveeffects and the potential therapeutic mechanisms of loach(Misgurnus anguillicaudatus) lyophilized powder (MLP)on dimethylnitrosamine (DMN) induced liver fibrosis inrats. After treatment with MLP (50, 100, 200 mg/kg),alanine aminotransferase (ALT), aspartate aminotransferase(AST), albumin (Alb), total protein (TP) andhydroxyproline (Hyp) levels were detected, to assess thedestruction of hepatocytes and the extent of liver fibrosis. Matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), hyaluronic acid (HA), Laminin (LN),procollagen type-III (PC-III), collagen type-IV (C-IV), andtransforming growth factor-b1 (TGF-b1) contents in serumwere all tested using ELISA kits. Alpha-smooth muscleactin (a-SMA) and the tissue inhibitor of metalloproteinase-1 (TIMP-1) protein contents and distribution wereevaluated using western blot and immunohistochemicalanalysis. MLP significantly decreased the serum concentrationsof ALT, AST, Hyp, HA, LN, PC-III, C-IV, MMP-2,TIMP-1, a-SMA and TGF-b1, while increasing the contentsof Alb and MMP-9. No significant changes on TP serum concentrations were observed. These results suggest thatMLP has anti-hepatic fibrosis effects and its mechanism maybe associated with the attenuation of extracellular matrix(ECM) synthesis, the acceleration of ECM degradation,inhibition of hepatic stellate cells (HSCs) activation andTGF-b1 expression.