Life extension analysis of high speed ball bearing based on multi-parameter coupling

Guang Zeng,Chunjiang Zhao,Xiaokai Yu,Qiang Bian,Zhigang Xiao,Bingyang Liu 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.4

The internal contact nonlinear characteristics caused by the quasi-static properties of high-speed ball bearing is taken as a breakthrough point. Based on the L-P fatigue life theory, the bearing parameters and the preload load are used as the constraint variables to establish an overall bearing life extension model. Then, combined with the influence of geometric parameters on the osculation, the influence mechanism between spin-to-roll ratio and the life of the bearing are studied under the individual variation of the geometric parameters. Finally, the variation law of the bearing life, frictional heat generation and spin-to-roll ratio under the coupling changes of various parameters, and the priority of each parameter on the bearing life sensitivity, are investigated. The results show that the bearing life could be prolonged when the initial contact angle and the number of rolling elements increase but the inner and outer raceway curvature radius coefficients of the bearing and the preload force reduce. And the priority order of each parameter to bearing life sensitivity is as follows: the inner and outer raceway curvature radius coefficients shows the strongest influence on the bearing life, followed by the number of balls, and then the initial contact angle. This research provides a reliable theoretical basis for the design of high-speed ball bearings and life extension technology.

Amycolatopsis jiangsuensis sp. nov., a novel endophytic actinomycete isolated from a coastal plant in Jiangsu, China.

Xing, Ke,Liu, Wei,Zhang, Yue-Ji,Bian, Guang-Kai,Zhang, Wen-Di,Tamura, Tomohiko,Lee, Jung-Sook,Qin, Sheng,Jiang, Ji-Hong N.V. Swets en Zeitlinger 2013 Antonie van Leeuwenhoek Vol.103 No.2

<P>A novel actinomycete, designated strain KLBMP 1262(T), was isolated from a coastal plant Dendranthema indicum (Linn.) Des Moul collected from the coastal region of Nantong, Jiangsu Province, in east China and was studied in detail for its taxonomic position. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain KLBMP 1262(T) is a member of the genus Amycolatopsis. The 16S rRNA gene sequence similarity indicated that strain KLBMP 1262(T) is most closely related to Amycolatopsis sulphurea DSM 46092(T) (97.96 %), Amycolatopsis ultiminotia RP-AC36(T) (97.50 %) and Amycolatopsis jejuensis N7-3(T) (97.44 %); similarity to other type strains of the genus Amycolatopsis was less than 97.0 %. The organism was determined to have chemical and morphological features consistent with its classification in the genus Amycolatopsis such as meso-diaminopimelic acid as the diagnostic diamino acid in the cell wall peptidoglycan and arabinose and galactose as the diagnostic sugars. The predominant menaquinone was determined to be MK-9 (H(4)). The polar lipids detected were phosphatidylmethylethanolamine, phosphatidylethanolamine, an unknown aminophospholipid, two unknown glycolipids and several unknown lipids. The major fatty acids were found to be C(16:0), iso-C(16:0) and iso-C(15:0). DNA-DNA relatedness data, together with phenotypic differences, clearly distinguished the isolate from its closest relatives. On the basis of these phenotypic and genotypic data, the isolate is considered to represent a novel species, for which the name A. jiangsuensis sp. nov. is proposed. The type strain is KLBMP 1262(T) (=KCTC 19885 (T) = NBRC 108679(T)).</P>

기업가정신이 창업의지에 미치는 영향에 관한 연구

이주헌(Lee, Joo-Heon),변광학(Bian, Guang Xue) 한국벤처창업학회 2011 한국벤처창업학회 학술대회 Vol.2011 No.11

불확실한 경영환경은 사람들로 하여금 기업가정신의 발현을 요구하고 있다. 창업을 생각하는 사람은 물론 대기업 및 중소기업에 종사하는 종업원들도 기업가정신을 통한 혁신을 요구하는 혁신시대이다. 본 연구의 목적은 대학생들의 기업가정신이 창업의지에 어떤 영향을 미쳤는지 실증 분석하는 것이다. 선행연구의 정의에 따라 기업가정신은 위험감수성, 혁신성, 진취성으로 구성되었다. 본 연구에 의하면 대학생들의 위험감수성이 창업의지에 정의 영향을 미치지만 혁신성과 진취성은 창업의지에 영향을 미치지 않는 것으로 나타났다. Recent high uncertainty environments require people to have entrepreneurial orientations. Not only potential entrepreneurs who will start their businesses in short time but also employees of large and small business are demanded to have entrepreneurial orientations and innovativeness. The purpose of this article is to research whether entrepreneurial orientations of college students have any effects on entrepreneurial intentions. Based on the previous researches, entrepreneurial orientations are composed of three constructs, risk taking propensity, innovativeness, and proactiveness. This empirical research show that the risk taking propensity of college students has some influence on entrepreneurial intention. However, the innovativeness and the proactiveness of college students have no effects on entrepreneurial intention.

α-Bismuthene and beyond

Pawel KOWALCZYK,Ishan MAHAJAN,Simon BROWN,Guang BIAN,Tai-C. CHIANG,Witold KOZLOWSKI,Pawel DABROWSKI,Zbigniew KLUSEK 한국진공학회 2016 한국진공학회 학술발표회초록집 Vol.2016 No.8

Beneficial effects of andrographolide in a rat model of autoimmune myocarditis and its effects on PI3K/Akt pathway

Zhang, Qi,Hu, Li-qun,Li, Hong-qi,Wu, Jun,Bian, Na-na,Yan, Guang The Korean Society of Pharmacology 2019 The Korean Journal of Physiology & Pharmacology Vol.23 No.2

The study is to investigate effects of andrographolide on experimental autoimmune myocarditis (EAM). Lewis rats were immunized on day 0 with porcine cardiac myosin to establish EAM. The EAM rats were treated with either andrographolide (25, 50, 100 mg/kg/day) or vehicle for 21 days. An antigen-specific splenocytes proliferation assay was performed by using the cells from control rats immunized with cardiac myosin. Survival rates, myocardial pathology and myocardial functional parameters (left ventricle end-diastolic pressure, ${\pm}dP/dt$ and left ventricular internal dimension) of EAM rats received andrographolide were significantly improved. Andrographolide treatment caused an decrease in the infiltration of $CD3^+$ and $CD14^+$ positive cells in myocardial tissue. Moreover, andrographolide treatment caused a reduction in the plasma levels of tumor necrosis factor-alpha, interleukin-17 (IL-17) and myosin-antibody, and an increase in the level of IL-10 in EAM rats. Oral administration of andrographolide resulted in the decreased expression of p-PI3K, p-Akt without any change of PI3K and Akt. Further results indicate andrographolide significantly inhibited myosin-induced proliferation in splenocytes, and this effect was inhibited by co-treatment of SC79 (Akt activator). Our data indicate andrographolide inhibits development of EAM, and this beneficial effect may be due to powerful anti-inflammatory activity and inhibitory effect on PI3K/Akt pathway.

經營者のリ一ダ 一 シップは業績に顯在化するか

송원민호 ( Toshihiro Matsubara ),등조무 ( Zhao Wu Deng ),변희광 ( Xi Guang Bian ),고호인 ( Hao Jen Kao ) 한국인적자원관리학회 2006 인적자원관리연구 Vol.13 No.3

Beneficial effects of andrographolide in a rat model of autoimmune myocarditis and its effects on PI3K/Akt pathway

Qi Zhang,Li-qun Hu,Hong-qi Li,Jun Wu,Na-na-Bian,Guang Yan 대한약리학회 2019 The Korean Journal of Physiology & Pharmacology Vol.23 No.2

The study is to investigate effects of andrographolide on experimental autoimmune myocarditis (EAM). Lewis rats were immunized on day 0 with porcine cardiac myosin to establish EAM. The EAM rats were treated with either andrographolide (25, 50, 100 mg/kg/day) or vehicle for 21 days. An antigen-specific splenocytes proliferation assay was performed by using the cells from control rats immunized with cardiac myosin. Survival rates, myocardial pathology and myocardial functional parameters (left ventricle end-diastolic pressure, ± dP/dt and left ventricular internal dimension) of EAM rats received andrographolide were significantly improved. Andrographolide treatment caused an decrease in the infiltration of CD3+ and CD14+ positive cells in myocardial tissue. Moreover, andrographolide treatment caused a reduction in the plasma levels of tumor necrosis factor-alpha, interleukin-17 (IL-17) and myosin-antibody, and an increase in the level of IL-10 in EAM rats. Oral administration of andrographolide resulted in the decreased expression of p-PI3K, p-Akt without any change of PI3K and Akt. Further results indicate andrographolide significantly inhibited myosin-induced proliferation in splenocytes, and this effect was inhibited by co-treatment of SC79 (Akt activator). Our data indicate andrographolide inhibits development of EAM, and this beneficial effect may be due to powerful anti-inflammatory activity and inhibitory effect on PI3K/Akt pathway.