인터넷쇼핑몰 Flicker이미지에 대한 사용자의 시각적 피로 연구

맹총(Cong Meng),김세화(Sehwa Kim) 한국애니메이션학회 2011 한국애니메이션학회 학술대회지 Vol.2011 No.10

Estimation for the Random Errors of Reflector Surfaces Using Measured Data

Meng Wang,Cong-Si Wang,Wei Wang,Jin-Zhu Zhou,Peng Li 한국정밀공학회 2014 International Journal of Precision Engineering and Vol. No.

In this research, a novel error-decomposition scheme is developed to determine efficiently the random errors of reflector surface basedon the discrete measurement data. The least squares fitting of semi-closed B-spline surface is employed. Subsequently, a spatialstatistical analysis is performed to determine whether the spatial independent distribution of the sampled data points is attained fora given confidence level. This research rests on the assumption that the measurement errors of instruments are trivial compared withrandom errors caused by machining and assembly inaccuracies. The presented methodology has been applied to the surface analysisof a 3.7 m reflector antenna.

Quantitative evaluation method for machining accuracy retention of CNC machine tools considering degenerate trajectory fluctuation

Cong Feng,Zhaojun Yang,Chuanhai Chen,Jinyan Guo,Hailong Tian,Fanning Meng 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.6

Accuracy retention is an important performance index of CNC machine tools. At present, research on the evaluation of machining accuracy retention of CNC machine tools mainly focuses on accuracy value of a fixed time point or different time periods, but studies on the fluctuation degree of degradation trajectory related to time change are limited. Extracting simple and effective degradation characteristics of machining accuracy and then evaluating machining accuracy retention considering fluctuation of degradation trajectory are necessary. The volume error model of CNC machine tools is established on the basis of multibody system theory in this study. Three-dimensional volume error vector is transformed into one-dimensional machining accuracy degradation by calculating offset distance between spatial error and origin points. Degradation data obtained via regular measurement and calculation are used to establish the complete degradation trajectory model of the CNC machine tools machining accuracy using radial basis function interpolation method according to the fluctuation degree of degradation trajectory, and concepts of average degradation rate and average degradation amount are defined. Lastly, examples showed that these two indicators can intuitively reflect fluctuation degree of machining accuracy degradation of CNC machine tools and effectively and quantitatively evaluate accuracy retention of CNC machine tools. The quantitative evaluation method of accuracy retention of CNC machine tools defined in this study considers the fluctuation degree of accuracy degradation trajectory. The quantitative evaluation index of accuracy retention demonstrates satisfactory engineering application because it can reflect not only the accuracy change of a single machine tool but also accurately compare the accuracy retention between different machine tools.

Neurotrophic Artemin Promotes Motility and Invasiveness of MIA PaCa-2 Pancreatic Cancer Cells

Meng, Ling-Xin,Chi, Yu-Hua,Wang, Xiang-Xu,Ding, Zhao-Jun,Fei, Li-Cong,Zhang, Hong,Mou, Ling,Cui, Wen,Xue, Ying-Jie Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.5

Objective: To analyze the capacity of neurotrophic artemin to promote the motility and invasiveness of MIA PaCa-2 pancreatic cancer cells. Methods: MIA PaCa-2 was cultured in vitro and studied using transwell chambers for motility and invasiveness on treatment with different concentrations of aArtemin or its receptor $GFR{\alpha}3$ were also determined. Expression of matrix metalloproteinase-2 (MMP-2) and epithelial cadherin (E-cadherin) was quantified using RT-PCR and Western blotting. Results: MIA PaCa-2 pancreatic cancer cell motility and invasiveness was significantly increased with artemin and its receptor $GFR{\alpha}3$ with dose dependence (P<0.01). MMP-2 production was also significantly increased (t = 6.35, t = 7.32), while E-cadherin was significantly lowered (t = 4.27, t = 5.61) (P <0.01). Conclusion: Artemin and its receptor $GFR{\alpha}3$ can promote pancreatic cancer cell motility and invasiveness and contribute to aggressive behavior. The mechanism may be related to increased expression of MMP-2 molecule and down-regulation of E-cadherin expression.

The Interlaminar Mechanical and Impact Properties of Fibre Metal Laminates Reinforced with Graphene

Fanglin Cong,Shuo Wang,Linlin,Meng Cao,Zehui Jia,Zhiqiang Zhou,Xu Cui 한국섬유공학회 2022 Fibers and polymers Vol.23 No.5

Glass fibre aluminium laminate (Glare) is widely used in various fields because of its excellent performance. However, its properties can be further enhanced by adding nanofillers, such as graphene, to the matrix. Graphene is a costeffectivetoughening agent because of its excellent specific strength, economy and good compatibility. The interlaminarmechanical and dynamic impact properties of Glare were improved by uniformly dispersed graphene (0, 0.2, 0.3, 0.5 and1.0 wt%). The interlaminar mechanical properties (short beam shear and single lap test) of the graphene-modified (0.5 wt%)Glare were increased by 42.24 % and 25.65 %, respectively, compared with the pure epoxy resin matrix. At a graphenecontent of 1.0 wt%, the Charpy impact energy and strength increased by 163.58 % and 126.33 %, respectively, and reachedthe maximum value. The microscopic images and schematic diagrams illustrated the toughening mechanism of graphene,including the enhancement of the aluminium/resin and fibre/resin interfaces and the performance of the resin matrix. Thetoughening of the resin matrix was achieved through the formation of a mechanical linkage between the graphene and thematrix, which indicated that more time and energy would be required to destroy it.

Mean-value first-order saddlepoint approximation based collaborative optimization for multidisciplinary problems under aleatory uncertainty

Debiao Meng,Hong-Zhong Huang,Zhonglai Wang,Ning-Cong Xiao,Xiao-Ling Zhang 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.10

Reliability-based multidisciplinary design optimization (RBMDO) has received increasing attention in engineering design for achievinghigh reliability and safety in complex and coupling systems (e.g., multidisciplinary systems). Mean-value first-order saddlepoint approximation(MVFOSA) is introduced in this paper and is combined with the collaborative optimization (CO) method for reliabilityanalysis under aleatory uncertainty in RBMDO. Similar to the mean-value first-order second moment (MVFOSM) method, MVFOSAapproximated the performance function with the first-order Taylor expansion at the mean values of random variables. MVFOSA usessaddlepoint approximation rather than the first two moments of the random variables to estimate the probability density and cumulativedistribution functions. MVFOSA-based CO (MVFOSA-CO) is also formulated and proposed. Two examples are provided to show theaccuracy and efficiency of the MVFOSA-CO method.

Photocatalytic Generated Oxygen Species Properties by Fullerene Modified Two-Dimensional MoS₂ and Degradation of Ammonia Under Visible Light

Zou, Cong-Yang,Meng, Ze-Da,Zhao, Wei,Oh, Won-Chun Materials Research Society of Korea 2021 한국재료학회지 Vol.31 No.6

In this study, photocatalytic degradation of ammonia in petrochemical wastewater is investigated by solar light photocatalysis. Two-dimensional ultra-thin atomic layer structured MoS₂ are synthesized via a simple hydrothermal method. We examine all prepared samples by means of physical techniques, such as SEM-EDX, HRTEM, FT-IR, BET, XRD, XPS, DRS and PL. And, we use fullerene modified MoS₂ nanosheets to enhance the activity of photochemically generated oxygen (PGO) species. Surface area and pore volumes of the MoS₂-fullerene samples significantly increase due to the existence of MoS₂. And, PGO oxidation of MB, TBA and TMST, causing its concentration in aqueous solution to decrease, is confirmed by the results of PL. The generation of reactive oxygen species is detected through the oxidation reaction from 1,5-diphenyl carbazide (DPCI) to 1,5-diphenyl carbazone (DPCO). It is found that the photocurrent density and the PGO effect increase in the case with modified fullerene. The experimental results show that this heterogeneous catalyst has a degradation of 88.43% achieved through visible light irradiation. The product for the degradation of NH₃ is identified as N₂, but not NO^2- or NO^3-.

Seroprevalence of Encephalitozoon cuniculi and Toxoplasma gondii in domestic rabbits (Oryctolagus cuniculus) in China

Qing-Feng Meng,Wei-Lin Wang,Xiao-Ting Ni,Hai-Bin Li,Gui-Zhe Yao,Xiao-Lin Sun,Wei-Li Wang,Wei Cong 대한기생충학열대의학회 2015 The Korean Journal of Parasitology Vol.53 No.6

The breeding of domestic rabbits (Oryctolagus cuniculus) for human consumption has a long tradition in China. Infections that can affect the production of meat or even be transmitted from animals to humans are important to monitor, especially for public health reasons as well as for their impact on animal health. Thus, a total of 1,132 domestic rabbit sera from 4 regions in China were collected for serological screening for Encephalitozoon cuniculi and for Toxoplasma gondii by ELISA and modified agglutination test (MAT), respectively. Antibodies to E. cuniculi were detected in 248/1,132 (21.9%) sera tested while antibodies against T. gondii revealed a seroprevalence of 51/1,132 (4.5%). We believe that the present results are of epidemiological implications and public health importance due to the acknowledged susceptibility of humans to E. cuniculi and T. gondii infections. Therefore, routine screening tests of domestic rabbits are proposed considering the zoonotic potential of these parasites.

Inhibition of the interaction between Hippo/YAP and Akt signaling with ursolic acid and 3′3-diindolylmethane suppresses esophageal cancer tumorigenesis

Ruo Yu Meng,Cong Shan Li,Dan Hu,Soon-Gu Kwon,Hua Jin,Ok Hee Chai,Ju-Seog Lee,김수미 대한약리학회 2023 The Korean Journal of Physiology & Pharmacology Vol.27 No.5

Hippo/YAP signaling hinders cancer progression. Inactivation of this pathway contributes to the development of esophageal cancer by activation of Akt. However, the possible interaction between Akt and Hippo/YAP pathways in esophageal cancer progression is unclear. In this study, we found that ursolic acid (UA) plus 3′3-diindolylmethane (DIM) efficiently suppressed the oncogenic Akt/Gsk-3β signaling pathway while activating the Hippo tumor suppressor pathway in esophageal cancer cells. Moreover, the addition of the Akt inhibitor LY294002 and the PI3K inhibitor 3-methyladenine enhanced the inhibitory effects of UA plus DIM on Akt pathway activation and further stimulated the Hippo pathway, including the suppression of YAP nuclear translocation in esophageal cancer cells. Silencing YAP under UA plus DIM conditions significantly increased the activation of the tumor suppressor PTEN in esophageal cancer cells, while decreasing p-Akt activation, indicating that the Akt signaling pathway could be down-regulated in esophageal cancer cells by targeting PTEN. Furthermore, in a xenograft nude mice model, UA plus DIM treatment effectively diminished esophageal tumors by inactivating the Akt pathway and stimulating the Hippo signaling pathway. Thus, our study highlights a feedback loop between the PI3K/Akt and Hippo signaling pathways in esophageal cancer cells, implying that a low dose of UA plus DIM could serve as a promising chemotherapeutic combination strategy in the treatment of esophageal cancer.

Anthocyanin Extracted from Purple Sweet Potato Alleviates Dextran Sulfate Sodium-Induced Colitis in Mice by Suppressing Pyroptosis and Altering Intestinal Flora Structure

Rongpeng Li,Cong Li,Jing Chen,Fei Jiang,Nana Xu,Guokai Dong,Jiebang Jiang,Meng Wang 한국식품영양과학회 2024 Journal of medicinal food Vol.27 No.2

The objective of this study was to examine the impact and underlying mechanisms of pelargonidin-3-galactoside (Pg3gal) produced from purple sweet potatoes on colonic inflammation induced by dextran sulfate sodium (DSS)in a murine model of ulcerative colitis (UC). C57BL/6J mice were categorized into four groups (n = 6 per group):DSS+Pg3gal, control, control+Pg3gal, and DSS. Colitis was induced by providing free access to 3% DSS for 10 days. TheDSS+Pg3gal model mice received DSS concurrently with intragastric Pg3gal (25 mg/kg). The health of the mice was carefullymonitored on a regular basis, and scores for the Disease Activity Index (DAI) were documented. A histological assessmentwas conducted using hematoxylin and eosin staining to evaluate the extent of mucosal injury present. The expression levels ofIL-6, NLRP3, ASC, cleaved-Caspase-1, TNF-a, N-GSDMS, and cleaved-IL-1b proteins were evaluated by Western blotanalysis. The process of 16S rRNA sequencing was carried out to examine the composition and relative abundance of gutmicrobiotas within the intestines of the mice. The DAI results revealed that Pg3gal significantly attenuated the DSS-inducedUC in mice. In addition, it successfully alleviated the decline in colon size, improved the condition of colonic tissue, andsignificantly inhibited the production of proinflammatory cytokines, such as IL-6, IL-1b, and TNF-a, in the colon tissues. Additionally, Pg3gal modulated the DSS-induced imbalanced gut microbiota, as evidenced by decreased Proteobacteria andDeferribacteres and simultaneous elevation in Firmicutes, Bacteroidetes, and Verrucomicrobia. In summary, Pg3gal alleviatedDSS-induced UC by inhibiting pyroptosis in intestinal epithelial cells and enhancing the structural integrity of the gutmicrobiota.