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Progress in the Study of Inflammatory Bowel Disease Patients with Primary Non-Responsiveness
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作者 Yixue Liu Xiaoping Tan 《Journal of Biosciences and Medicines》 2024年第1期72-85,共14页
Inflammatory bowel disease (IBD) is a group of chronic, nonspecific intestinal inflammatory disorders characterized by localized and systemic inflammation. The use of biologic agents in the treatment of IBD patients i... Inflammatory bowel disease (IBD) is a group of chronic, nonspecific intestinal inflammatory disorders characterized by localized and systemic inflammation. The use of biologic agents in the treatment of IBD patients is widespread, and the occurrence of primary non-responsiveness during treatment is also significant. This review briefly summarizes the possible reasons for primary non-responsiveness in IBD patients, as well as predictive markers and current strategies to address it, providing a theoretical reference for early identification and management of IBD patients who do not respond to treatment. 展开更多
关键词 Inflammatory Bowel Disease Primary non-responsiveness Anti-Tumor Necrosis Factor
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Outcome after Discharge from Hospital of Children with Complicated Severe Acute Malnutrition and Predictors Factors of Non-Response during Outpatient Treatment, in Senegal
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作者 Abou Ba Aliou Thiongane +4 位作者 Babacar Niang Younoussa Keïta Fatou Ly Aliou Abdoulaye Ndongo Ousmane Ndiaye 《Open Journal of Pediatrics》 2023年第4期473-483,共11页
Introduction: Malnutrition is a public health problem. It is responsible for high morbidity and mortality in children aged 6 - 59 months. The aim of this study was to determine the outcome of children with complicated... Introduction: Malnutrition is a public health problem. It is responsible for high morbidity and mortality in children aged 6 - 59 months. The aim of this study was to determine the outcome of children with complicated severe acute malnutrition after hospital discharge. Methods: This is a descriptive and analytical cross-sectional study conducted from March 1 to November 31, 2021 at the Albert Royer Children’s Hospital. Children discharged from hospital for complicated severe acute malnutrition were included. Results: A total of 103 children were included. The mean age of children at hospitalization was 16.41 ± 10.11 months and mean duration of follow-up after hospital discharge was 29.63 ± 8.59 months. Three children (2.91%) died after hospital discharge. The mean z-score of the weight-for-current height was -1.34 ± 1.08. Almost a quarter (24.27%) of the children remain acute malnourished with 3.88% of severe acute malnutrition (SAM). The predictors’ factors associated with non-response were weaning before 2 years of age (ORaj: 12.21;95% CI [6.82 - 18.44];p = 0.04) and tuberculosis (ORaj: 21.06;95% CI [12.54 - 41.09];p = 0.03). Conclusion: The rate of recovery of nutritional status in children with complicated severe acute malnutrition is satisfactory. Ablactation before the age of two and the existence of tuberculosis are significantly associated with non-recovery of nutritional status. 展开更多
关键词 CHILDREN Severe Acute Malnutrition Recovery non-response
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Stable response of low-gravity liquid non-linear sloshing in a circle cylindrical tank 被引量:1
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作者 贺元军 马兴瑞 王本利 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第10期1273-1285,共13页
Under pitch excitation, the sloshing of liquid in circular cylindrical tank includes planar motion, rotary motion and rotary motion inside planar motion. The boundaries between stable motion and unstable motion depend... Under pitch excitation, the sloshing of liquid in circular cylindrical tank includes planar motion, rotary motion and rotary motion inside planar motion. The boundaries between stable motion and unstable motion depend on the radius of the tank, the liquid height, the gravitational intension, the surface tensor and the sloshing damping. In this article, the differential equations of nonlinear sloshing are built first. And by variational principle, the Lagrange function of liquid pressure is constructed in volume intergration form. Then the velocity potential function is expanded in series by wave height function at the free surface. The nonlinear equations with kinematics and dynamics free surface boundary conditions through variation are derived. At last, these equations are solved by multiple-scales method. The influence of Bond number on the global stable response of nonlinear liquid sloshing in circular cylinder tank is analyzed in detail. The result indicates that variation of amplitude frequency response characteristics of the system with Bond, jump, lag and other nonlinear phenomena of liquid sloshing are investigated. 展开更多
关键词 circle cylindrical tank nonlinear sloshing low-gravity multiple scales method stable response
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Effect of nonlinear soil-structure interaction on seismic response of low-rise SMRF buildings 被引量:1
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作者 Prishati Raychowdhury Poonam Singh 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第4期541-551,共11页
The nonlinear behavior of a soil-foundation system may alter the seismic response of a structure by providing additional flexibility to the system and dissipating hysteretic energy at the soil-foundation interface. Ho... The nonlinear behavior of a soil-foundation system may alter the seismic response of a structure by providing additional flexibility to the system and dissipating hysteretic energy at the soil-foundation interface. However, the current design practice is still reluctant to consider the nonlinearity of the soil-foundation system, primarily due to lack of reliable modeling techniques. This study is motivated towards evaluating the effect of nonlinear soil-structure interaction (SSI) on the seismic responses of low-rise steel moment resisting frame (SMRF) structures. In order to achieve this, a Winkler- based approach is adopted, where the soil beneath the foundation is assumed to be a system of closely-spaced, independent, nonlinear spring elements. Static pushover analysis and nonlinear dynamic analyses are performed on a 3-story SMRF building and the performance of the structure is evaluated through a variety of force and displacement demand parameters. It is observed that incorporation of nonlinear SSI leads to an increase in story displacement demand and a significant reduction in base moment, base shear and inter-story drift demands, indicating the importance of its consideration towards achieving an economic, yet safe seismic design. 展开更多
关键词 soil-structure interaction Winkler modeling nonlinear analysis seismic response low-rise steel momentresisting frame
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Type 2 diabetes with good glycemic control have improved insulin response and lower non-esterified fatty acid level after a meal challenge
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作者 Norhayati Yahaya Win Mar Kyi +1 位作者 Norhayati Mohd Noor Wan Mohamed Wan Bebakar 《Journal of Diabetes Mellitus》 2012年第1期1-7,共7页
Background: Pathogenesis of type 2 diabetes (T2DM) involves defects in β-cell function with impaired first and second phase insulin response, and reduced insulin sensitivity. Diabetic dyslipidemia is an important and... Background: Pathogenesis of type 2 diabetes (T2DM) involves defects in β-cell function with impaired first and second phase insulin response, and reduced insulin sensitivity. Diabetic dyslipidemia is an important and common risk factor for coronary heart disease (CHD). Aims: This study examined the effect of glycemic control on post prandial insulin and lipid parameters in response to a standardised meal challenge among Type 2 diabetes patients with good and poor glycemic control. Methods: We cross-sectionally studied 31 T2DM patients with good glycemic control and 32 T2DM patients with poor glycemic control. Subjects were given, after minimum 10 hours of fasting, a standard meal containing 58% fat. Fasting and serial postprandial blood samples were taken over 8 hours to determine levels of triglyceride, direct LDL-C, apoB lipoprotein, non-esterified-fatty-acid, insulin and blood glucose. Results: Post prandial NEFA was significantly higher in poor controlled diabetes patients compared to good control diabetes patients (p = 0.019), and post-hoc analysis showed significant difference from 3 hours post prandial to 4 hours post prandial, where p= 0.021. Although the difference in insulin between the 2 groups did not reach statistical significance (p =0.058), post-hoc analysis showed significant difference between the 2 groups from fasting to 1 hour post prandial (p = 0.034) despite postprandial glucose being significantly higher in poor controlled diabetes patients (p < 0.001), throughout the postprandial period. Conclusion: T2DM patients with good glycemic control have improved insulin response with lower non-esterified fatty acid. 展开更多
关键词 INSULIN response non-Esterified FATTY Acid Standardised MEAL Type 2 Diabetes Glycemic Control
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Increased Levels of p53 and PARP-1 in EL-4 Cells Probably Related with the Immune Adaptive Response Induced by Low Dose Ionizing Radiation in vitro 被引量:6
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作者 GUANG-HUI CHENG NING WU +4 位作者 DE-Fu JIANG HONG-GUANG ZHAO QIAN ZHANG JIAN-FENG WANG SHou-LIANG GONG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2010年第6期487-495,共9页
Objective This paper is to explore the DNA repair mechanism of immune adaptive response (AR) induced by low dose radiation (LDR), the changes of mRNA levels and protein expressions of p53, ATM, DNA-PK catalytic su... Objective This paper is to explore the DNA repair mechanism of immune adaptive response (AR) induced by low dose radiation (LDR), the changes of mRNA levels and protein expressions of p53, ATM, DNA-PK catalytic subunit (DNA-PKcs) and PARP-1 genes in the LDR-induced AR in EL-4 cells. Methods The apoptosis and cell cycle progression of EL-4 cells were detected by flow cytometry in 12 h after the cells received the pre-exposure of 0.075 Gy X-rays (inductive dose, D 1) and the succeeding high dose irradiation (challenge dose, D2; 1.0, 1.5, and 2.0 Gy X-rays, respectively) with or without wortmannin (inhibitor of ATM and DNA-PK) and 3-aminobenzamid (inhibitor of PARP-1). And the protein expressions and mRNA levels related to these genes were detected with flow cytometry and reverse transcription-polymerase chain reaction in 12 h after irradiation with D2. Results The mRNA and protein expressions of p53 and PARP-1 in EL-4 cells in the D1 + D2 groups were much lower than those in the D2 groups, and those of PARP-1 in the 3-AB + D2 and the 3-AB + D1 + D2 groups were much lower than those in the D2 and the D1 + D2 groups. The percentage of apoptotic EL-4 cells in the 3-AB + D1 + D2 groups was much higher than that in the D1 + D2 groups, that in the G0/G1 and the G2 + M phases was much higher, and that in the S phase were much lower. Although the ATM and DNA-PKcs mRNA and protein expressions in wortmannin + D1 + D2 groups were much lower than those in the D1 + D2 groups, there were no significant changes in the apoptosis and cell cycle progression between the wortmannin + D1 + D2 and the D1 + D2 groups. Conclusion PARP-1 and p53 might play important roles in AR induced by LDR. 展开更多
关键词 low dose radiation (LDR) Adaptive response (AR) DNA repair
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Effect of Cycloheximide on the Adaptive Response Induced by Low Dose Radiation 被引量:4
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作者 CAI Lu AND LIu SHUZHENGDepartment of Radiation Biology, Institute of Radiation Medicine, Norman Bethune University of Medical Sciences, Changchun 130021, China Corresponding author 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1992年第1期46-52,共7页
Human lymphocytes pre-exposed to 10 mGy or 50 mGy of X-rays become less sensitive to subsequent large dose irradiation, exhibited lower rate of chromosome aberration than expected. This adaptive response could be inhi... Human lymphocytes pre-exposed to 10 mGy or 50 mGy of X-rays become less sensitive to subsequent large dose irradiation, exhibited lower rate of chromosome aberration than expected. This adaptive response could be inhibited by cycloheximide, a protein synthesis inhibitor for successive 2 h period ranging from 0.5h before to 4h after the low dose exposure, indicating that the adaptive response was directly related with the protein synthesis. 展开更多
关键词 In Effect of Cycloheximide on the Adaptive response Induced by low Dose Radiation
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Physiological and Molecular Analyses of Low-Salinity Stress Response in the Cuttlefish(Sepia pharaonis)Juveniles 被引量:1
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作者 XIN Hongwei WU Kunlan +5 位作者 YUAN Yimeng ZHAO Yun SONG Weiwei WANG Chunlin MU Changkao LI Ronghua 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第4期969-976,共8页
As a stenohaline species,the survival of Sepia pharaonis can be affected by salinity significantly.This study aimed to explore the function of decreasing salinity on the survival of Sepia pharaonis,which can provide a... As a stenohaline species,the survival of Sepia pharaonis can be affected by salinity significantly.This study aimed to explore the function of decreasing salinity on the survival of Sepia pharaonis,which can provide an advanced production guide on the culture of S.pharaonis in the rainy season.Salinity was gradually decreased from 29 to 22 within 48 h to acclimate S.pharaonis to a low-salinity environment.After ten days of breeding under low-salinity of 22,the death rate was high.In this process,changes in tissue and cell structures in the larval liver,biochemical indicators,and osmoregulation-related gene expression were examined.In-terestingly,hepatocytes in the low-salinity group were irregular,had dissolved tissue inclusions,and contained vacuolized cells.There-fore,low salinity caused severe damages at a cellular level that can elevate the mortality rate.A gradual decline in salinity limited the full adaptation of S.pharaonis.Biochemical indicators and osmoregulation-related gene expression changed similarly.For instance,the trend of malondialdehyde(MAD)as a product of lipid peroxidation reflected the degree of damage to the body by free radicals.The antioxidant system of S.pharaonis could cope with oxidative stress caused by the change in salinity to a certain extent.Osmo-regulation-related genes’expression also showed an optimistic result,that is,S.pharaonis responded positively to the change in sali-nity by adjusting the expression of osmoregulation-related genes.Conversely,the increase in mortality at day 10 also proved the weak adaptation capability of S.pharaonis.This study indicated that S.pharaonis can adapt to a low-salinity environment with a li-mited extent. 展开更多
关键词 Sepia pharaonis low salinity physiological responses biochemical indicators osmoregulation-related genes
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Proprotein convertase subtilisin/kexin type 9 inhibitor non responses in an adult with a history of coronary revascularization:A case report 被引量:1
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作者 Liu Yang Yan-Yan Xiao +5 位作者 Liang Shao Chang-Sheng Ouyang Yao Hu Bin Li Li-Feng Lei Hong Wang 《World Journal of Clinical Cases》 SCIE 2022年第19期6728-6735,共8页
BACKGROUND Familial hypercholesterolemia(FH)is an autosomal dominant disorder that is characterized by severely increased low-density lipoprotein(LDL)cholesterol levels.At the same time,elevated LDL levels accelerated... BACKGROUND Familial hypercholesterolemia(FH)is an autosomal dominant disorder that is characterized by severely increased low-density lipoprotein(LDL)cholesterol levels.At the same time,elevated LDL levels accelerated the development of coronary heart disease.Several classes of drugs are currently in use to treat FH.Proprotein convertase subtilisin/kexin type 9 inhibitor(PCSK9i)is novel one of these.CASE SUMMARY This manuscript reports a case of FH that responded modestly after treatment with PCSK9i and statin drugs.Of even more concern is that the patient frequently admitted to the hospital during a 12-year follow-up period.Subsequently,we identified a heterozygous mutation,1448G>A(W483X)of the LDL receptor(LDLR)in this patient.The serum levels of PCSK9(proprotein convertase subtilisin/kexin type 9)in the patient was 71.30±26.66 ng/mL,which is close the average level reported in the literature.This LDLR mutation affects LDLR metabolism or structure,which may make it unsuitable for use of PCSK9i.CONCLUSION Our outcome demonstrates that LDLR-W483X represents a partial loss-of-function LDLR and may contribute to PCSK9i ineffective. In the meanwhile, additional measures aretherefore required (particularly with gene sequencing or change the treatment plan) must beinitiated as early as possible. Genetic testing for clinically challenging cases who do not respond toPCSK9i therapy is very helpful. 展开更多
关键词 Coronary artery disease Familial hypercholesterolemia low-density lipoprotein receptor mutation non response Proprotein convertase subtilisin/kexin type 9 inhibitor
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Predictors of non-response to cardiac resynchronization therapy implantation in patients with class Ⅰ indications: the markedly dilated left ventricular end-diastolic dimension and the presence of fragmented QRS 被引量:3
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作者 Yi-Ran HU Wei HUA +7 位作者 Sheng-Wen YANG Min GU Hong-Xia NIU Li-Gang DING Jing WANG Ran JING Xiao-Han FAN Shu ZHANG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2019年第7期514-521,共8页
Background Cardiac resynchronization therapy(CRT)is a highly effective treatment in patients with a class I recommendation.However,a small proportion of the strictly selected patients still fail to respond.This study ... Background Cardiac resynchronization therapy(CRT)is a highly effective treatment in patients with a class I recommendation.However,a small proportion of the strictly selected patients still fail to respond.This study was designed to identify predictors of non-response in patients with class I indications for CRT and determine the non-response probability of the patients.Methods A total of 296 consecutive patients with a class I recommendation received CRT from January 2009 to January 2017 were retrospectively analyzed.Multivariate logistic regression analysis was performed to identify predictors for non-response(defined as cardiac death,heart transplantation,or HF hospitalization during 1-year follow-up).Results Among 296 patients,30(10.1%)met non-response.Multivariate analysis demonstrated that non-response to CRT was associated with a fragmented QRS(odd ratio(OR)=2.86,95%CI:1.14–7.12;P=0.025)and left ventricular end-diastolic dimension(LVEDD)≥77 mm(OR=3.02,95%CI:1.17–7.82;P=0.022).Patients with both of the predictors had a non-response probability of 46.2%(95%CI:19.1%–73.3%).Conclusion In patients with left bundle branch block and wider QRS duration,the proportion of non-response to CRT is not low in real world.The presence of the dilated LVEDD or fragmented QRS is a strong predictor of non-response to CRT.The probability of non-response in the patients with the two predictors was 46.2%. 展开更多
关键词 Cardiac RESYNCHRONIZATION therapy CLASS I indication non-response PREDICTORS
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A METHOD FOR THE ANALYSIS OF DYNAMIC RESPONSE OF STRUCTURE CONTAINING NON-SMOOTH CONTACTABLE INTERFACES 被引量:3
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作者 刘晶波 刘书 杜修力 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1999年第1期63-72,共10页
A novel single-step method is proposed for the analysis of dynamic response of visco-elastic structures containing non-smooth contactable interfaces. In the method, a two-level algorithm is employed for dealing with a... A novel single-step method is proposed for the analysis of dynamic response of visco-elastic structures containing non-smooth contactable interfaces. In the method, a two-level algorithm is employed for dealing with a nonlinear boundary condition caused by the dynamic contact of interfaces. At the first level, an explicit method is adopted to calculate nodal displacements of global viscoelastic system without considering the effect of dynamic contact of interfaces and at the second level, by introducing contact conditions of interfaces, a group of equations of lower order is derived to calculate dynamic contact normal and shear forces on the interfaces. The method is convenient and efficient for the analysis of problems of dynamic contact. The accuracy of the method is of the second order and the numerical stability condition is wider than that of other explicit methods. 展开更多
关键词 non-smooth contactable interfaces visco-elastic structure dynamic response
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THE NON-AXISYMMETRICAL DYNAMIC RESPONSE OF TRANSVERSELY ISOTROPIC SATURATED POROELASTIC MEDIA 被引量:9
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作者 ZHANG Yin-ke(张引科) +1 位作者 HUANG Yi(黄义) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第1期63-78,共16页
The Blot's wave equations of transversely isotropic saturated poroelastic media excited hy non-axisymmetrical harmonic source were solved by means of Fourier expansion and Hankel transform. Then the components of ... The Blot's wave equations of transversely isotropic saturated poroelastic media excited hy non-axisymmetrical harmonic source were solved by means of Fourier expansion and Hankel transform. Then the components of total stress in porous media are expressed with the solutions of Biot's wave equations. The method of research on non-axisymmetrical dynamic response of saturated porous media is discussed, and a numerical result is presented. 展开更多
关键词 Biot's wave equations transversely isotropic saturated poroelastic media non-axisymmetrical dynamic response
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A time-domain nonlinear effective-stress non-Masing approach of ground response analysis of Guwahati city, India 被引量:2
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作者 Devdeep Basu Madhulatha Boga Arindam Dey 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第1期61-75,共15页
The response of subsoil strata subjected to seismic excitations plays an important role in governing the response of the overlying superstructures at any site. Ground response analysis(GRA) helps to assess the influen... The response of subsoil strata subjected to seismic excitations plays an important role in governing the response of the overlying superstructures at any site. Ground response analysis(GRA) helps to assess the influence of soil characteristics on the propagating seismic stress waves from the bedrock level to the ground surface during an earthquake. For the northeastern region of India, located in the highest seismic zone in the country, conducting an extensive GRA study is of prime importance. Conventionally, most of the GRA studies are carried out using the equivalent linear method, which, being a simplistic approach, cannot capture the nonlinear behavior of soil during seismic shaking. This paper presents the outcomes of a one-dimensional effective stress based nonlinear GRA conducted for Guwahati city(located in northeast India) incorporating the non-Masing load/unload/reload characteristics. The various ground response parameters evaluated from this study help in assessing the ground shaking, soil amplification, and site responses expected in this region. 2D contour maps, which are representative of the distribution of some of these parameters throughout Guwahati city, are also developed. The results presented herein can serve as guidelines for the design of foundations and superstructures in this region. 展开更多
关键词 GROUND response analysis nonlinear effective STRESS APPROACH non-masing criteria GROUND response parameters soil amplification
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Analysis of genotype differences of rice response to low Zn^(2+) activity and some morphological characteristics 被引量:5
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作者 WANG Renmin, Dept of Agro YANG Xiao’e and YANG Yuai, Dept of Agri Chemistry, ZheJiang Agri Univ, Hangzhou 310029, China 《Chinese Rice Research Newsletter》 1998年第3期11-12,共2页
Zinc deficiency is one of the most widespreadmicro-nutritional disorder for rice. To solve the problem, screening Zn-efficient cultivars isan available method and understanding geno-
关键词 Analysis of genotype differences of rice response to low Zn activity and some morphological characteristics root
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Low Frequency Dispersion Mechanism of Dielectric Response for Oil-paper Insulation Diagnosis 被引量:14
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作者 ZHOU Lijun LI Xianlang WU Guangning 《高电压技术》 EI CAS CSCD 北大核心 2013年第8期1873-1880,共8页
Both the real part and imaginary part of complex permittivity approximately have a log-linear frequency dependency at low fre- quencies, especially at ultra-low frequencies under conditions of different moisture conce... Both the real part and imaginary part of complex permittivity approximately have a log-linear frequency dependency at low fre- quencies, especially at ultra-low frequencies under conditions of different moisture concentrations and temperatures, which is recognized as the low frequency dispersion (LFD). In order to explain this dispersion, a new mechanism of dielectric response of LFD of oil-paper insula- tion is proposed. A simplified one-dimensional mathematical model of concentration polarization carrier caused by slow migration is developed and solved, which indicates that ion mobility is closely related to the size of gap and the adsorption capacity of cellulose molecu- lar chains to ions. A stochastic statistical model of the carrier mobility induced LFD is also developed. Moreover, actual tests under 50 °C and 2% moisture content were put forward, as well as simulations with according current waveforms. The simulation results agreed well with the experimental data in that concentration polarization of carriers caused by slow migration is the probable cause of low frequency dispersion of dielectric response for oil-paper insulation diagnosis. 展开更多
关键词 分散介质 油纸绝缘 绝缘诊断 低频率 机制 离子迁移率 一维数学模型 载流子迁移率
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A method for stochastic seismic response analysis of non-classically damped structures 被引量:2
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作者 徐清 高存臣 王君杰 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2004年第1期75-84,共10页
A method to calculate the stationary random response of a non-classically damped structure is proposed that features clearly-defined physical meaning and simple expression. The method is developed in the frequency dom... A method to calculate the stationary random response of a non-classically damped structure is proposed that features clearly-defined physical meaning and simple expression. The method is developed in the frequency domain. The expression of the proposed method consists of three terms, i.e., modal velocity response, modal displacement response, and coupled (between modal velocity and modal displacement response). Numerical results from the parametric study and three example structures reveal that the modal velocity response term and the coupled term are important to structural response estimates only for a dynamic system with a tuned mass damper. In typical cases, the modal displacement term can provide response estimates with satisfactory accuracy by itself, so that the modal velocity term and coupled term may be ignored without loss of accuracy. This is used to simplify the response computation of non-classically damped structures. For the white noise excitation, three modal correlation coefficients in closed form are derived. To consider the modal velocity response term and the coupled term, a simplified approximation based on white noise excitation is developed for the case when the modal velocity response is important to the structural responses. Numerical results show that the approximate expression based on white noise excitation can provide structural responses with satisfactory accuracy. 展开更多
关键词 non-classically damped structures random response modal correlation coefficients
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Low Distortion Quick Response Noise Filter Realized withAverage Peaks Method
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作者 Lei Liu Jianyue Ren +2 位作者 Ko-Wen Jwo Yu Zhang Xianfeng Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第5期39-44,共6页
The filter proposed in this paper is expected to reduce noise whose frequency is lower than higher order harmonics of real signals.It is based on the distributive characteristics of noise,and uses analog circuits to s... The filter proposed in this paper is expected to reduce noise whose frequency is lower than higher order harmonics of real signals.It is based on the distributive characteristics of noise,and uses analog circuits to select the high peak and low peak of the input signal and applies their average in order to reduce random noise.So it has no cutoff frequency and higher order harmonics of real signals are remained.As a result,it gives an instant response to changes in input signals and retains the integrity of real signals.Furthermore,it has only a small phase delay.The simulation results of slew rate,phase delay and spectral analysis under MULTISIM indicate that the quick response noise filter achieves a high slew rate of 472 V/ms and the phase shift is nearly zero.By having it used in a color tester design,it is also demonstrated that the proposed filter effectively reduces noise and remains signal integrity.With the filter 's help,the relative standard deviation of the spectrograph decreases from 1% to 0.22%,indicating better stability. 展开更多
关键词 low distortion quick response FILTER cutoff frequency
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NONLINEAR TRANSIENT RESPONSE OF STAY CABLE WITH VISCOELASTICITY DAMPER IN CABLE-STAYED BRIDGE 被引量:1
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作者 陈水生 孙炳楠 冯义卿 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第6期664-671,共8页
Taking the bending stiffness, static sag, and geometric non-linearity into consideration, the space nonlinear vibration partial differential equations were derived. The partical differential equations were discretized... Taking the bending stiffness, static sag, and geometric non-linearity into consideration, the space nonlinear vibration partial differential equations were derived. The partical differential equations were discretized in space by finite center difference approximation, then the nonlinear ordinal differential equations were obtained. A hybrid method involving the combination of the Newmark method and the pseudo-force strategy was proposed to analyze the nonlinear transient response of the inclined cable-dampers system subjected to arbitrary dynamic loading. As an example, two typical stay cables were calculated by the present method. The results reveal both the validity and the deficiency of the viscoelasticity damper for vibration control of stay cables. The efficiency and accuracy of the proposed method is also verified by comparing the results with those obtained by using Runge-Kutta direct integration technique. A new time history analysis method is provided for the research on the stay cable vibration control. 展开更多
关键词 stay cable transient response vibration control non-linearity
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Solution of false alarm and slow response in flame detector
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作者 Song Wengang Zhang Lijun +2 位作者 Zheng Zhanqi Wang Guanying Zhang Jianming 《Journal of Southeast University(English Edition)》 EI CAS 2019年第2期174-178,共5页
A new flame detector with one ultraviolet and two infrared detectors is designed. The ultraviolet detector is of rapid response(≤10 μs) while the two infrared detectors usually have a response time of more than 5 ms... A new flame detector with one ultraviolet and two infrared detectors is designed. The ultraviolet detector is of rapid response(≤10 μs) while the two infrared detectors usually have a response time of more than 5 ms. The ultraviolet detector is applied to deal with the flame of large scales. When facing the flame of mid or small scales, the three detectors cooperate. Employing the high-order derivatives of the sample data of the infrared circuits to improve the sensitivity, the response speed is greatly improved. The data of the temperature sensor is used to adjust circuit parameters in real time, thus reducing the effect of temperature drift. The flame detectors are tested at different distances and the response time is as rapid as 0.65 ms. The test results show that the new flame detector has the characteristics of high speed and a low rate of false alarms. 展开更多
关键词 flame detector rapid response low false alarm rate DERIVATIVE
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Low embankment dynamic response under vehicle traffic loads in arid-oasis areas
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作者 WAN Qi YANG Xiao-hua +1 位作者 YIN Pei-jie BAO Han 《Journal of Mountain Science》 SCIE CSCD 2020年第7期1776-1789,共14页
The use of low embankments is of significant concern for ecological protection in aridoasis areas.Based on the project of Sansha Expressway located in Kashgar City,Xinjiang,China,physical model tests were conducted in... The use of low embankments is of significant concern for ecological protection in aridoasis areas.Based on the project of Sansha Expressway located in Kashgar City,Xinjiang,China,physical model tests were conducted in this study to investigate the dynamic response of the low embankment as per the effects of road structure,load amplitude,load frequency,load cycle,and moisture content.The dynamic stress is shown to increase with load amplitude while the dynamic elastic modulus decreases with load amplitude under short-term loading.The load frequency slightly influences the soil’s dynamic behavior;higher frequencies can improve the dynamic elastic modulus of the subgrade soil.The moisture content has greater influence on the mechanical properties of the subsoil than that of subgrade layer.The subgrade bears the majority of the traffic load as the stress dissipates to 37%of the whole value on its surface.The number of load cycles has the greatest effect on the dynamic response among the influencing factors tested.The dynamic elastic modulus with the type of long-term dynamic loading is only 40%-52%of that with static loading across the entire depth range.The dynamic stress shows significant accumulation with load cycles over the long-term dynamic loading test and becomes stable after 8×10~4 cycles of loading.An equation is established to quantify the cumulative dynamic stress in the low embankment under long-term dynamic loading conditions. 展开更多
关键词 low embankment Dynamic response Model test Moisture content Dynamic elastic modulus Cumulative dynamic stress
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