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Blade-Loss-Caused rubbing Dynamic Characteristics of Rotor-Bladed Disk-Casing System

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第1期35卷 116-125页

作者： Zeng Jin Ma Hui Ma Xinxing Wu Zhiyuan Qin Zhaoye School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819P.R.China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240P.R.China Shanghai Institute of Space Power-Sources Shanghai 200245P.R.China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084P.R.China

Considering the elastic supports,the finite element model of rotor-bladed disk-casing system is established using commercial software ANSYS/*** that broken blade is released from the disk,the complicate rubbing responses of unbalanced rotor-bladed disk-casing system are studied under different operational *** addition,influences of both plastic deformation of blade and casing failure are *** results show that there exist some multiple even fractional frequencies in the transient and steady vibration responses of unbalanced ***,one nodal diameter vibration of bladed disk coupling with the lateral vibration of the shaft as well as the first order bending vibration of blade can be excited under low operational speed,while the first order bending vibration of blade coupling with the lateral vibration of disk-shaft is easily excited under high operational *** rubbing process,three distinct contact states can be observed:broken blade-casing contact,broken blade-blade component-casing contact and broken blade-casing contact/blade component-casing contact/blade *** is worth noting that the third contact state is related to the operational *** the increase of operational speed,self-contact in the blade may occur.

关键词： rotor-bladed disk-casing system blade loss rubbing casing failure elastic supports

The surface rubbing effect on morphologies of LC droplets and electro-optic properties of flexible PDLC films

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Science China Chemistry 2009年第12期52卷 2329-2335页

作者： LIU GuoZhu XIA DuLing YANG WenJun HUANG ZiQiang State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 610054China School of Optoelectronic Information University of Electronic Science and Technology of ChinaChengdu 610054China No.58 Research Institute China Electronics Technology Group CorporationWuxi 214035China

The flexible polymer dispersed liquid crystal (PDLC) film with threshold voltage V10 and saturation driving voltage V90 as low as 0.34 V/μm and 0.77 V/μm,respectively,has been prepared successfully by polymerization induced phase separation (PIPS). The surface rubbing effect on morphologies of liquid crystals (LC) droplets and electro-optic properties of PDLC films has been studied experimentally and theoretically. We use a CVC (Color Video Camera) and a SEM (Scan Electron Microscope) to detect and characterize morphologies of LC droplets in the net of polymer. The result reveals that almost all the smaller LC droplets exhibit in the rubbing direction uniformly,and the texture of PDLC is similar to that of H-PDLC. Meanwhile,compared with the sample of the non-rubbing disposal,the response time declines evidently by 11.2 ms (i.e.,the rising time τrise) and 27.2 ms (i.e.,the decaying time τdown),and the contrast ratio is improved from 18.5 to 35.9. Such a result can be attributed to the surface rubbing effect.

关键词： polymer dispersed liquid crystal (PDLC) surface rubbing effect morphologies threshold voltage

The correlation between keratoconus and eye rubbing: a review

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International Journal of Ophthalmology(English edition) 2019年第11期12卷 1775-1781页

作者： Hatim Najmi Yara Mobarki Khalid Mania Bashaer Altowairqi Mohammed Basehi Mohammed Salih Mahfouz Mona Elmahdy Department of Ophthalmology King Fahad Hospital of the UniversityAl Khobar 34445Saudi Arabia King Abdulaziz University Hospital Jeddah 21589Saudi Arabia King Fahad Central Hospital Jazan 45142Saudi Arabia Department of Emergency King Fahad Hospital of the UniversityAl Khobar 34445Saudi Arabia Department of Family and Community Medicine Faculty of MedicineJazan UniversityJazan 45142Saudi Arabia

Keratoconus is a non-inflammatory disorder which is gradual in development;corneal thinning and ectatic protrusion characterizes it. Keratoconus prevalence varies between different regions depending on several factors that affecting its prevalence. There are risk factors for developing keratoconus such as demographic and environmental factors. It was suggested that eye rubbing was associated with the development of keratoconus. The main aim of this review was to summarize the literature data about keratoconus and to identify the role of eyerubbing in the aetiology of the disease. A number of 24 articles was reviewed through the Pub Med, Google Scholar and Research Gates. There are many keywords used such as keratoconus, aetiology of keratoconus, eye rubbing, keratoconus prevalence, keratoconus and eye rubbing correlation. We concluded that eye rubbing causes the thinning of keratocyte, and the degree of effect of eye rubbing depends on the period and force of performing eye rubbing. It is recommended to avoid eye rubbing to prevent keratoconus, this can be achieved by avoiding itching and treating dryness of the eye and avoiding wearing eye lenses.

关键词： keratoconus eye rubbing keratoconus risk factors

Nonlinear dynamic behavior of rubbing rotor under interaction between bending and torsional vibrations

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Journal of Harbin Institute of Technology(New Series) 2002年第2期9卷 117-120页

作者：刘占生崔颖韩万金隋玉秋黄文虎 Sch. of Energy Sci. and Eng. Harbin Inst. of Technol. Harbin 150001 China

The nonlinear dynamic behavior of a rubbing rotor system was studied with a mathematical model established with the eccentricity and interaction between bending and torsional vibrations taken into consideration. The nonlinear vibrational response of a rubbing rotor was analyzed using numerical integral, spectroscopic analysis and Poince mapping method, which made it possible to have better understanding of the vibrational characteristics of partial rubbing and complete circular rubbing rotors. The numerical results reveal the response of torsional vibration mainly takes a form of superchronous motion, and its frequency decreases as the rotational speed increases when partial rubbing occurs, and the response of torsional vibration is synchronous when complete circular rubbing occurs. The comparison of the dynamics of rubbing rotors with and without the interaction between bending and torsional vibrations shows the interaction between bending and torsional vibrations advances the rotational speed, at which the response of bending vibration changes from a synchronous motion into a quasi periodic motion, and the interaction between bending and torsional vibrations reduces stability of the rubbing rotor.

关键词： interaction between bending and torsional vibrations rubbing rotor bifurcation

rubbing Mura产生机理及改善研究

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液晶与显示 2018年第6期33卷 469-474页

作者：杨德波王云志陶雄李伟钟野罗春重庆京东方光电科技有限公司重庆400714

rubbing Mura是以接触式摩擦工艺生产TFT_LCD产品时常见的顽固缺陷,尤其在HADS产品上不良发生率更高。本文对rubbing Mura产生的原因及机理进行分析,发现该不良由TFT基板上的源极线(Source Data,SD)附近的rubbing弱区漏光引起。研究了Ru... 详细信息

rubbing Mura是以接触式摩擦工艺生产TFT_LCD产品时常见的顽固缺陷,尤其在HADS产品上不良发生率更高。本文对rubbing Mura产生的原因及机理进行分析,发现该不良由TFT基板上的源极线(Source Data,SD)附近的rubbing弱区漏光引起。研究了rubbing强度(Nip值)、rubbing布型号、rubbing布寿命、黑矩阵(Black Matrix,BM)加宽和SD减薄对HADS产品的rubbing Mura的影响,选择最优的工艺条件,rubbing Mura的不良发生率由2.4%降至0%,改善效果明显。

关键词： rubbing Mura HADS产品 rubbing弱区工艺条件

Frictional Melanosis of rubbing Thighs in Iraqi Patients

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Journal of Cosmetics, Dermatological Sciences and Applications 2014年第3期4卷 203-211页

作者： Khalifa E. Sharquie Adil A. Noaimi Attaa A. Hajji Department of Dermatology and Venereology Baghdad Teaching Hospital Baghdad Iraq

Background: Frictional melanosis of rubbing inner thighs is a common problem among Iraqi females causing great psychological and cosmetic impact. It might simulate lifa disease but it is a different entity. It is unfortunately not reported in the medical literatures although commonly encountered in daily clinical practice. Objective: To evaluate the hyperpigmentation of inner aspects of thighs in Iraqi females as an isolated pigmentary problem. Patient and Methods: Sixty patients with frictional melanosis of rubbing thighs were seen in Department of Dermatology, Baghdad Teaching Hospital in this case descriptive, clinical and histopathological study, during the period from April 2011 to March 2012. Any associated skin problems were also noticed like folliculitis and boils at area of friction. Forty individuals were enrolled in the present work as the healthy control group. The pigmentation was assessed by clinical, Wood’s light and histopathological examinations (H&E and Fontana stains). Body mass index was obtained for all patients and obesity was graded according to WHO recommendations. Results: The ages of patients ranged between 19 - 52 (32.86 ± 7.65) years, with 59 (98.3%) females and 1 (1.6%) male. By Wood’s light examination, accentuation in pigmentation was observed in 39 (58%) patients, while 21 (42%) of lesions showed no change. Body mass index was ranged from 23.3 - 43.6 (34.04 ± 4.13), history of vigorous rubbing of pigmented area with washing tool (lifa) was positive in 46 (76.6%) patients. Skin biopsies in 10 patients showed pure dermal melanophages in 3 of biopsies with slight melanosis of basal layer of epidermis, while the other 7 biopsies showed mainly increase in basal melanin. There was a statistically significant association between obesity and the severity of pigmentation of the inner thighs. Forty control individuals (2 males and 38 females) were assessed, their ages ranged from 19 - 50 (31.72 ± 6.40) years. All females were within normal weig

关键词： Frictional Melanosis rubbing Thighs Iraqi Patients

Acoustic emission technique based rubbing identification for Rotor-bearing systems

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Science China Mathematics 2001年第S1期44卷 459-465页

作者： HE Yongyong CHU Fulei WANG Qingyu State Key Laboratory of Tribology, Department of Precision Instruments, Tsinghua University, Beijing 100084, China

rubbing is the frequent and dangerous fault in the rotating machine, and efficient identi-fication of the rubbing is a hot research subject in the field of fault diagnosis. In this paper, a newrubbing identification method is proposed, which is based on the acoustic emission technique. Inthis method, the acoustic emission signal of the rubbing in the multi-support rotor-bearing systemis acquired by the acoustic emission sensor, and then the continuous wavelet transform is utilizedto analyze this signal. Based on the rubbing mechanism, the frequency feature of the multiple fre-quency relation in the instantaneous frequency wave is extracted as the rubbing identification fea-ture. The experimental results prove that the proposed method is efficient and feasible.

关键词： rubbing acoustic emission wavelet transform

Research on rubbing-fault Diagnosis System in High-speed Rotor based on LabVIEW

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International Journal of Plant Engineering and Management 2018年第1期23卷 59-64页

作者： WEI Xie-ben CHEN Shu-qin SUN Pei-ming Jieyang Vocational and Technical College Guangdong Jieyang 522000China Jieyang DALI Mould Factory Co. LtdGuangdong Jieyang 522000China

The rubbing between rotors and determiners is the common mechanic vibration fault in the operation of rotation machinery. During the operation of equipment, in order to meet the demand of high speed and efficiency of machinery, the gap between the active and passive parts of the rotor system become smaller, which results in the common rubbing fault of rotors and stators. This essay studies the fault diagnosis of high speed rotors based on invented instrument and shows the measurement and research of the signals of rubbing failure of high speed rotors. The research introduces the designed software and hardware which are experimented and testified on Bentley rotor experiment platform. The system has theoretical and applicative meaning in practical projects.

关键词： high-speed rotor LabVIEW rubbing fault diagnosis

Eye rubbing as a Possible Cause of Clinical Progressive Keratoconus in a Forme Fruste Keratoconic Family

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Open Journal of Ophthalmology 2015年第1期5卷 19-22页

作者： George D. Kymionis Konstantinos I. Tsoulnaras Stella V. Blazaki Michael A. Grentzelos Vardinoyiannion Eye Institute of Crete (VEIC) Faculty of Medicine University of Crete Heraklion Crete Greece Department of Ophthalmology Bascom Palmer Eye Institute University of Miami Miami FL USA

We report a case of a 21-year-old male patient who underwent corneal cross-linking (CXL) due to bilateral progressive keratoconus. Topographical screening of his family members was performed for the detection of possible familial keratoconus and showed abnormal topographical patterns resembling to Forme Fruste Keratoconus (FFK) in all the members of his family. The reported keratoconic patient that underwent CXL was the only individual of this family that referred eye rubbing in his personal ocular history;ocular and medical history of the other family members was clear. Eye rubbing could be a possible adjuvant risk factor that contributes to conversion of FFK to clinical progressive keratoconus.

关键词： Eye rubbing Family Forme Fruste Keratoconus Topography