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Clinical effects of nonconvulsive electrotherapy combined with mindfulness-based stress reduction and changes of serum inflammatory factors in depression
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作者 Zhi-Wen Gu Chun-Ping Zhang +1 位作者 Li-Ping Chen Xiong Huang 《World Journal of Psychiatry》 SCIE 2024年第5期653-660,共8页
BACKGROUND Depression is a common and serious psychological condition,which seriously affects individual well-being and functional ability.Traditional treatment methods include drug therapy and psychological counselin... BACKGROUND Depression is a common and serious psychological condition,which seriously affects individual well-being and functional ability.Traditional treatment methods include drug therapy and psychological counseling;however,these methods have different degrees of side effects and limitations.In recent years,nonconvulsive electrotherapy(NET)has attracted increasing attention as a noninvasive treatment method.However,the clinical efficacy and potential mechanism of NET on depression are still unclear.We hypothesized that NET has a positive clinical effect in the treatment of depression,and may have a regulatory effect on serum inflammatory factors during treatment.AIM To assess the effects of NET on depression and analyze changes in serum inflammatory factors.METHODS This retrospective study enrolled 140 patients undergoing treatment for depression between May 2017 and June 2022,the observation group that received a combination of mindfulness-based stress reduction(MBSR)and NET treatment(n=70)and the control group that only received MBSR therapy(n=70).The clinical effectiveness of the treatment was evaluated by assessing various factors,including the Hamilton Depression Scale(HAMD)-17,self-rating idea of suicide scale(SSIOS),Pittsburgh Sleep Quality Index(PSQI),and levels of serum inflammatory factors before and after 8 wk of treatment.The quality of life scores between the two groups were compared.Comparisons were made using t and χ^(2) tests.RESULTS After 8 wk of treatment,the observation group exhibited a 91.43%overall effectiveness rate which was higher than that of the control group which was 74.29%(64 vs 52,χ^(2)=7.241;P<0.05).The HAMD,SSIOS,and PSQI scores showed a significant decrease in both groups.Moreover,the observation group had lower scores than the control group(10.37±2.04 vs 14.02±2.16,t=10.280;1.67±0.28 vs 0.87±0.12,t=21.970;5.29±1.33 vs 7.94±1.35,t=11.700;P both<0.001).Additionally,there was a notable decrease in the IL-2,IL-1β,and IL-6 in both groups after treatment.Furthermore,the observation group exhibited superior serum inflammatory factors compared to the control group(70.12±10.32 vs 102.24±20.21,t=11.840;19.35±2.46 vs 22.27±2.13,t=7.508;32.25±4.6 vs 39.42±4.23,t=9.565;P both<0.001).Moreover,the observation group exhibited significantly improved quality of life scores compared to the control group(Social function:19.25±2.76 vs 16.23±2.34;Emotions:18.54±2.83 vs 12.28±2.16;Environment:18.49±2.48 vs 16.56±3.44;Physical health:19.53±2.39 vs 16.62±3.46;P both<0.001)after treatment.CONCLUSION MBSR combined with NET effectively alleviates depression,lowers inflammation(IL-2,IL-1β,and IL-6),reduces suicidal thoughts,enhances sleep,and improves the quality of life of individuals with depression. 展开更多
关键词 DEPRESSION Nonconvulsive electrotherapy Mindfulness-based stress reduction Serum inflammatory factors Clinical effect Hamilton Depression Scale
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基于RF和MLR的土壤重金属影响因素分析及生物有效性预测 被引量:1
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作者 潘泳兴 陈盟 +1 位作者 王櫹橦 刘楠 《农业环境科学学报》 CAS CSCD 北大核心 2024年第4期845-857,共13页
为探究影响土壤中重金属累积和生物有效性的因素,以桂北地区某铅锌矿流域为研究对象,综合运用单因子指数法、风险评价编码法(RAC)、多元线性回归模型(MLR)和随机森林模型(RF)进行土壤重金属(Pb、Zn、Cu和Cr)累积影响因素分析及生物有效... 为探究影响土壤中重金属累积和生物有效性的因素,以桂北地区某铅锌矿流域为研究对象,综合运用单因子指数法、风险评价编码法(RAC)、多元线性回归模型(MLR)和随机森林模型(RF)进行土壤重金属(Pb、Zn、Cu和Cr)累积影响因素分析及生物有效性预测。结果表明:研究区Cr含量无超标且空间分布相对均匀(变异系数为0.51);Cu、Pb和Zn的含量均值(分别为52.58、280.31 mg·kg^(-1)和654.71 mg·kg^(-1))均大于广西西江流域土壤重金属背景值,在思的河山前和地下河入口处全量和生物有效性均较大,对土壤生态环境具有一定风险;对于重金属全量分布和生物有效态的影响因素,阳离子交换量(CEC)、黏粒(Clay)、土壤有机质(SOM)和铁铝氧化物对Cr影响较大,SOM、Clay、pH和铁铝氧化物对Cu影响较大,pH、电导率(EC)和Clay对Pb影响较大,CEC、pH、土壤质地和铁铝氧化物对Zn影响较大;生物有效性预测结果显示RF和MLR均可较好地预测土壤重金属的全量与次生相,其中RF预测的R2区间为0.44~0.93,MLR预测的R2区间为0.30~0.72,RF预测结果表现更为准确。 展开更多
关键词 土壤重金属 影响因素 生物有效性预测 随机森林模型(rf) 多元线性回归模型(MLR)
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A Calculation Method of Double Strength Reduction for Layered Slope Based on the Reduction of Water Content Intensity
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作者 Feng Shen Yang Zhao +1 位作者 Bingyi Li Kai Wu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期221-243,共23页
The calculation of the factor of safety(FOS)is an important means of slope evaluation.This paper proposed an improved double strength reductionmethod(DRM)to analyze the safety of layered slopes.The physical properties... The calculation of the factor of safety(FOS)is an important means of slope evaluation.This paper proposed an improved double strength reductionmethod(DRM)to analyze the safety of layered slopes.The physical properties of different soil layers of the slopes are different,so the single coefficient strength reduction method(SRM)is not enough to reflect the actual critical state of the slopes.Considering that the water content of the soil in the natural state is the main factor for the strength of the soil,the attenuation law of shear strength of clayey soil changing with water content is fitted.This paper also establishes the functional relationship between different reduction coefficients.Then,a USDFLD subroutine is programmed using the secondary development function of finite element software.Controlling the relationship between field variables and calculation time realizes double strength reduction applicable to the layered slope.Finally,by comparing the calculation results of different examples,it is proved that the stress and displacement distribution of the critical slope state obtained by the improved method is more realistic,and the calculated safety factor is more reliable.The newly proposedmethod considers the difference of intensity attenuation between different soil layers under natural conditions and avoids the disadvantage of the strength reduction method with uniform parameters,which provides a new idea and method for stability analysis of layered and complex slopes. 展开更多
关键词 Double strength reduction slopes stability water content factor of safety numerical methods
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基于PCA-RF组合模型的福建省空气负氧离子浓度预测研究
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作者 彭继达 张春桂 《能源与环保》 2024年第1期17-24,共8页
空气负氧离子(NOI)浓度是评价空气新鲜和清洁程度的重要指标。为了提高NOI浓度的监测能力,综合考虑气象要素和遥感因子,分析NOI浓度的关键影响因子,利用皮尔逊相关分析、PCA分析和随机森林机器学习方法(RF)构建了福建区域NOI浓度的PCA-R... 空气负氧离子(NOI)浓度是评价空气新鲜和清洁程度的重要指标。为了提高NOI浓度的监测能力,综合考虑气象要素和遥感因子,分析NOI浓度的关键影响因子,利用皮尔逊相关分析、PCA分析和随机森林机器学习方法(RF)构建了福建区域NOI浓度的PCA-RF预测模型。研究发现,(1)NOI浓度分布与风速(W_(air))、空气温度(T_(air))、大气压强(P_(air))、能见度(I_(VIS))、气溶胶光学厚度(h_(AOD))、植被指数(I_(NDVI))、湿度指数1(I_(NDMI1))、植被供水指数(I_(VSWI))和亮度指数(I_(NDSI))呈显著相关(均通过0.01显著性检验),其中W_(air)、I_(VIS)、I_(NDVI)和I_(VSWI)与NOI浓度呈正相关,T_(air)、P_(air)、h_(AOD)、I_(NDMI1)和I_(NDSI)与NOI浓度呈负相关。(2)主成分数量为7时,方差累计贡献率达到93.36%,能够代表所有因子的大部分信息。(3)PCA-RF模型最佳的ntree和mtry分别为400和7。对福建区域NOI浓度影响较大的前3个因子依次为P_(air)、I_(VIS)和I_(VSWI)。(4)PCA-RF模型在验证集上的RMSE为803.73 ions/cm^(3),R^(2)为0.44,MAE为548.79 ions/cm^(3)。 展开更多
关键词 空气负氧离子 气象因子 遥感因子 PCA-rf 预测模型
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Response reduction factor of irregular RC buildings in Kathmandu valley 被引量:2
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作者 Hemchandra Chaulagain Hugo Rodrigues +3 位作者 Enrico Spacone Ramesh Guragain Radhakrishna Mallik Humberto Varum 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第3期455-470,共16页
Most current seismic design includes the nonlinear response of a structure through a response reduction factor (R). This allows the designer to use a linear elastic force-based approach while accounting for nonlinea... Most current seismic design includes the nonlinear response of a structure through a response reduction factor (R). This allows the designer to use a linear elastic force-based approach while accounting for nonlinear behavior and deformation limits. In fact, the response reduction factor is used in modem seismic codes to scale down the elastic response of a structure. This study focuses on estimating the actual 'R' value for engineered design/construction of reinforced concrete (RC) buildings in Kathmandu valley. The ductility and overstrength of representative RC buildings in Kathmandu are investigated. Nonlinear pushover analysis was performed on structural models in order to evaluate the seismic performance of buildings. Twelve representative engineered irregular buildings with a variety of characteristics located in the Kathmandu valley were selected and studied. Furthermore, the effects of overstrength on the ductility factor, beam column capacity ratio on the building ductility, and load path on the response reduction factor, are examined. Finally, the results are further analyzed and compared with different structural parameters of the buildings. 展开更多
关键词 RC buildings pushover analysis ductility reduction factor OVERSTRENGTH response reduction factor
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Strength reduction factors for seismic analyses of buildings exposed to near-fault ground motions 被引量:2
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作者 Qu Honglue Zhang Jianjing J.X. Zhao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2011年第2期195-209,共15页
To estimate the near-fault inelastic response spectra, the accuracy of six existing strength reduction factors (R) proposed by different investigators were evaluated by using a suite of near-fault earthquake records... To estimate the near-fault inelastic response spectra, the accuracy of six existing strength reduction factors (R) proposed by different investigators were evaluated by using a suite of near-fault earthquake records with directivity-induced pulses. In the evaluation, the force-deformation relationship is modelled by elastic-perfectly plastic, bilinear and stiffness degrading models, and two site conditions, rock and soil, are considered. The R-value ratio (ratio of the R value obtained from the existing R-expressions (or the R-p-T relationships) to that from inelastic analyses) is used as a measurement parameter. Results show that the R-expressions proposed by Ordaz & Perez-Rocha are the most suitable for near-fault ground motions, followed by the Newmark & Hall and the Berrill et al. relationships. Based on an analysis using the near-fault ground motion dataset, new expressions of R that consider the effects of site conditions are presented and verified. 展开更多
关键词 strength reduction factors near-fault ground motion response spectra force-deformation relationship
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Strength and stiffness reduction factors for infilled frames with openings 被引量:1
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作者 Luis D.Decanini Laura Liberatore Fabrizio Mollaioli 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第3期437-454,共18页
Framed structures are usually infilled with masonry walls. They may cause a significant increase in both stiffness and strength, reducing the deformation demand and increasing the energy dissipation capacity of the sy... Framed structures are usually infilled with masonry walls. They may cause a significant increase in both stiffness and strength, reducing the deformation demand and increasing the energy dissipation capacity of the system. On the other hand, irregular arrangements of the masonry panels may lead to the concentration of damage in some regions, with negative effects; for example soft story mechanisms and shear failures in short columns. Therefore, the presence ofinfill walls should not be neglected, especially in regions of moderate and high seismicity. To this aim, simple models are available for solid infills walls, such as the diagonal no-tension strut model, while infilled frames with openings have not been adequately investigated. In this study, the effect of openings on the strength and stiffness of infilled frames is investigated by means of about 150 experimental and numerical tests. The main parameters involved are identified and a simple model to take into account the openings in the infills is developed and compared with other models proposed by different researchers. The model, which is based on the use of strength and stiffness reduction factors, takes into account the opening dimensions and presence of reinforcing elements around the opening. An example of an application of the proposed reduction factors is also presented. 展开更多
关键词 infilled frames OPENINGS STRENGTH STIFFNESS reduction factor
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Spectra of seismic force reduction factors of MDOF systems normalized by two characteristic periods 被引量:1
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作者 Li Xiao Tong Genshu Zhang Lei 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2020年第1期53-69,共17页
Seismic force reduction factor(SFRF) spectra of shear-type multi-degree-of-freedom(MDOF) structures are investigated. The modified Clough model, capable of considering the strength-degradation/hardening and stiffnessd... Seismic force reduction factor(SFRF) spectra of shear-type multi-degree-of-freedom(MDOF) structures are investigated. The modified Clough model, capable of considering the strength-degradation/hardening and stiffnessdegradation, is adopted. The SFRF mean spectra using 102 earthquake records on a typical site soil type(type C) are constructed with the period abscissa being divided into three period ranges to maintain the peak features at the two sitespecific characteristic periods. Based on a large number of results, it is found that the peak value of SFRF spectra may also exist for MDOF, induced by large high-mode contributions to elastic base shear, besides the mentioned two peak values. The variations of the stiffness ratio λk and the strength ratio λF of the top to bottom story are both considered. It is found that the SFRFs for λF ≤λk are smaller than those for λF > λk. A SFRF modification factor for MDOF systems is proposed with respect to SDOF. It is found that this factor is significantly affected by the story number and ductility. With a specific λF(= λk0.75), SFRF mean spectra are constructed and simple solutions are presented for MDOF systems. For frames satisfying the strong column/weak beam requirement, an approximate treatment in the MDOF shear-beam model is to assign a post-limit stiffness 15%-35% of the initial stiffness to the hysteretic curve. SFRF spectra for MDOF systems with 0.2 and 0.3 times the post-limit stiffness are remarkably larger than those without post-limit stiffness. Thus, the findings that frames with beam hinges have smaller ductility demand are explained through the large post-limit stiffness. 展开更多
关键词 seismic force reduction factor multi-degree of freedom modifi ed Clough model characteristic period highmode eff ect post-limit stiff ness analysis
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Crest Factor Reduction for OFDM Using Selective Subcarrier Degradation 被引量:1
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作者 R. Neil Braithwaite 《ZTE Communications》 2011年第4期25-31,共7页
This paper describes a crest factor reduction (CFR) method that reduces peaks in the time domain by modifying selected data subcarriers within an OFDM signal. The data subcarriers selected for modification vary with... This paper describes a crest factor reduction (CFR) method that reduces peaks in the time domain by modifying selected data subcarriers within an OFDM signal. The data subcarriers selected for modification vary with each symbol interval and are limited to those subcarriers whose aata elements are mapped onto the outer boundary of the constellation. In the proposed method, a set of peaks are identified within an OFDM symbol interval. Data subcarriers whose data element has a positive or negative correlation with the set peak are selected. For a subcarrier with an outer element and a significant positive correlation, a bit error (reversal) is intentionally introduced. This moves the data element to the opposite side of the constellation. Outer elements on negatively-correlatea subcarriers are increased in magnitude along the real or imaginary axis. Experimental results show that selecting the correct subcarriers for bit reversals and outward enhancements reduces the peak-to-average power ratio (PAPR) of the OFDM signal to a target value and limits in-band degradation measured by bit error rate (BER) and error vector magnitude (EVM). 展开更多
关键词 crest factor reduction OFDM PAPR wireless communication system digital transmitter
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High-Risk Rural Road Safety Study and Determining the Crash-Reduction Factors for High-Risk Rural-Road Usage 被引量:1
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作者 Ranjit Prasad Godavarthy Eugene R. Russell 《Journal of Transportation Technologies》 2016年第1期1-8,共8页
More than 32,000 motorists are killed on U.S. roads and streets annually, and approximately 54% of the accidents occur on rural roads. In an attempt to address and reduce these fatalities, the current transportation a... More than 32,000 motorists are killed on U.S. roads and streets annually, and approximately 54% of the accidents occur on rural roads. In an attempt to address and reduce these fatalities, the current transportation act, the Safe, Accountable, Flexible, Efficient Transportation Equality Act: A Legacy for Users (SAFETY-LU), elevated the Highway Safety Improvement Program (HSIP) to a core program and included a $90,000,000 High-Risk Rural Road Program (HRRRP) to address and significantly reduce traffic fatalities and incapacitating injuries on rural major or minor collectors, and/or rural local roads. While there were many challenges to properly implement the HRRRP in counties, this study provided important information that was needed to identify the predominant crash types on HRRRP-eligible roads and compiled a list of countermeasures for the predominant crash types that were identified on Kansas’ high-risk rural roads. For the gathered countermeasures, crash reduction factors (CRFs) were also provided from the literature review, and their values were validated by conducting interviews with Kansas county engineers/officials. This study provided valuable information for the county engineers and local government officials while they worked on improving the safety of high-risk rural roads using HRRRP funds. 展开更多
关键词 HRRR HSIP Rural Road Safety Crash reduction factors
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Simulation of higher order modes and loss factor of a new type of 500-MHz single cell superconducting cavity at SSRF 被引量:1
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作者 YU Haibo LIU Jianfei +5 位作者 HOU Hongtao LU Changwang WEI Yelong MA Zhenyu FENG Ziqiang MAO Dongqing 《Nuclear Science and Techniques》 SCIE CAS CSCD 2011年第5期257-260,共4页
In this paper,higher order modes(HOMs) and loss factor of a new type of 500-MHz superconducting cavity is studied,by simulating its broadband HOMs damping at different positions of the ferrite HOM-absorber and differe... In this paper,higher order modes(HOMs) and loss factor of a new type of 500-MHz superconducting cavity is studied,by simulating its broadband HOMs damping at different positions of the ferrite HOM-absorber and different lengths of the ferrite.The results show that the impedance and Q value of the HOMs in transverse and longitudinal modes could be greatly reduced.The HOM longitudinal impedance could be damped to meet the requirement of SSRF beam instability threshold.The calculated loss factor of the new SC cavity was compared with cavities at SSRF.It was estimated that the HOM absorber could absorb a total power of 3.16 kW at 4-mm beam bunch length. 展开更多
关键词 损耗因子 高阶模 超导腔 光源 上海 模拟 单细胞 纵向阻抗
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Upper bound solutions of stability factor of shallow tunnels in saturated soil based on strength reduction technique 被引量:8
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作者 黄阜 张道兵 +1 位作者 孙志彬 金启云 《Journal of Central South University》 SCIE EI CAS 2012年第7期2008-2015,共8页
Based on the upper bound theorem of limit analysis,the factor of safety for shallow tunnel in saturated soil is calculated in conjunction with the strength reduction technique.To analyze the influence of the pore pres... Based on the upper bound theorem of limit analysis,the factor of safety for shallow tunnel in saturated soil is calculated in conjunction with the strength reduction technique.To analyze the influence of the pore pressure on the factor of safety for shallow tunnel,the power of pore pressure is regarded as a power of external force in the energy calculation.Using the rigid multiple-block failure mechanism,the objective function for the factor of safety is constructed and the optimal solutions are derived by employing the sequential quadratic programming.According to the results of optimization calculation,the factor of safety of shallow tunnel for different pore pressure coefficients and variational groundwater tables are obtained.The parameter analysis shows that the pore pressure coefficient and the location of the groundwater table have significant influence on the factor of safety for shallow tunnel. 展开更多
关键词 强度折减技术 浅埋隧道 饱和土 稳定系数 上限解 孔隙水压力 安全系数 序列二次规划
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Effect of structural characteristics distribution on strength demand and ductility reduction factor of MDOF systems considering soil-structure interaction
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作者 Behnoud Ganjavi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第2期205-220,共16页
It is known that structural stiffness and strength distributions have an important role in the seismic response of buildings. The effect of using different code-specified lateral load patterns on the seismic performan... It is known that structural stiffness and strength distributions have an important role in the seismic response of buildings. The effect of using different code-specified lateral load patterns on the seismic performance of fixed-base buildings has been investigated by researchers during the past two decades. However, no investigation has yet been carried out for the case of soil-structure systems. In the present study, through intensive parametric analyses of 21,600 linear and nonlinear MDOF systems and considering five different shear strength and stiffness distribution patterns, including three code-specified patterns as well as uniform and concentric patterns subjected to a group of earthquakes recorded on alluvium and soft soils, the effect of structural characteristics distribution on the strength demand and ductility reduction factor of MDOF fixed-base and soil-structure systems are parametrically investigated. The results of this study show that depending on the level of inelasticity, soil flexibility and number of degrees-of-freedoms (DOFs), structural characteristics distribution can significantly affect the strength demand and ductility reduction factor of MDOF systems. It is also found that at high levels of inelasticity, the ductility reduction factor of low-rise MDOF soil-structure systems could be significantly less than that of fixed-base structures and the reduction is less pronounced as the number of stories increases. 展开更多
关键词 soil-structure interaction MDOF systems structural characteristic distribution inelastic behavior strength demand ductility reduction factor
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Study on strength reduction factors consid-ering the effect of classification of design earthquake
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作者 翟长海 谢礼立 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2006年第3期299-310,共12页
The strength reduction factors are not only the key factors in determining seismic action for force-based seismic design, but also the key parameters to derive the inelastic response spectra for performance-based seis... The strength reduction factors are not only the key factors in determining seismic action for force-based seismic design, but also the key parameters to derive the inelastic response spectra for performance-based seismic design. In this paper, with a high quality ground motion database that includes a reasonable-sized set of records from China, a statistical study on the strength reduction factors is conducted and a new expression of strength reduction factors involving classification of design earthquake, which is an important concept to determine design spectra in Chinese seismic design code, is proposed. The expression of strength reduction factors can reflect the ground motion characteristics of China to a certain extent and is particularly suitable for Chinese seismic design. Then, the influence effects of site condition, classification of design earthquake, period of vibration, ductility level, earthquake magnitude and distance to fault on strength reduction factors are investigated. It is concluded that the effect of site condition on the strength reduction factors cannot be neglected, especially for the short-period structures of higher ductility. The classification of design earthquake also has an important effect on strength reduction factors and it may be unsuitable to use the existing expressions of strength reduction factors to the design spectra of current Chinese seismic code. The earthquake magnitude has no practical effect on strength reduction factors and if the near-fault records with forward directivity effect are not taken into consideration, the effect of distance to fault on strength reduction factors can also be neglected. 展开更多
关键词 strength reduction factor site condition classification of design earthquake strong ground motion regression analysis
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Properties and appropriate conditions of stress reduction factor and thermal shock resistance parameters for ceramics
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作者 李卫国 成天宝 +1 位作者 张如炳 方岱宁 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第11期1351-1360,共10页
Through introducing the analytical problem of the plate with convection into the solution of the transient heat conduction thermal stress field model of the elastic plate, the stress reduction factor is presented expl... Through introducing the analytical problem of the plate with convection into the solution of the transient heat conduction thermal stress field model of the elastic plate, the stress reduction factor is presented explicitly in its dimensionless form. A new stress reduction factor is introduced for the purpose of comparison. The proper- ties and appropriate conditions of the stress reduction factor, the first and second ther- mal shock resistance (TSR) parameters for the high and low Biot numbers, respectively, and the approximation formulas for the intermediate Blot number-interval are discussed. To investigate the TSR of ceramics more accurately, it is recommended to combine the heat transfer theory with the theory of thermoelasticity or fracture mechanics or use a numerical method. The critical rupture temperature difference and the critical rup- ture dimensionless time can be used to characterize the TSR of ceramics intuitively and legibly. 展开更多
关键词 stress reduction factor thermal shock resistance (TSR) parameter ceram-ics Biot number Fourier number
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System Reliability Evaluation for Imperfect Networks Using Polygon-to-Chain Reduction
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作者 Mohamed-Larbi Rebaiaia Daoud Ait-Kadi 《American Journal of Operations Research》 2017年第3期201-224,共24页
The purpose of this paper is to propose a computational technique for evaluating the reliability of networks subject to stochastic failures. In this computation, a mathematical model is provided using a technique whic... The purpose of this paper is to propose a computational technique for evaluating the reliability of networks subject to stochastic failures. In this computation, a mathematical model is provided using a technique which incorporates the effect of the factoring decomposition theorem using polygon-to-chain and series-parallel reductions. The algorithm proceeds by identifying iteratively one of seven polygons and when it is discovered, the polygon is immediately removed and replaced by a simple chain after having changed the individual values of the reliability of each edge and each node of the polygon. Theoretically, the mathematical development follows the results presented by Satyanarayana & Wood and Theologou & Carlier. The computation process is recursively performed and less constrained in term of execution time and memory space, and generates an exact value of the reliability. 展开更多
关键词 Reliability NETWORKS Algorithms factorIZATION Polygon-to-Chain reduction Decomposition
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Limit equilibrium method(LEM) of slope stability and calculation of comprehensive factor of safety with double strength-reduction technique 被引量:14
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作者 DENG Dong-ping LI Liang ZHAO Lian-heng 《Journal of Mountain Science》 SCIE CSCD 2017年第11期2311-2324,共14页
When the slope is in critical limit equilibrium(LE) state, the strength parameters have different contribution to each other on maintaining slope stability. That is to say that the strength parameters are not simultan... When the slope is in critical limit equilibrium(LE) state, the strength parameters have different contribution to each other on maintaining slope stability. That is to say that the strength parameters are not simultaneously reduced. Hence, the LE stress method is established to analyze the slope stability by employing the double strengthreduction(DSR) technique in this work. For calculation model of slope stability under the DSR technique, the general nonlinear Mohr–Coulomb(M–C) criterion is used to describe the shear failure of slope. Meanwhile, the average and polar diameter methods via the DSR technique are both adopted to calculate the comprehensive factor of safety(FOS) of slope. To extend the application of the polar diameter method, the original method is improved in the proposed method. After comparison and analysis on some slope examples, the proposed method's feasibility is verified. Thereafter, the stability charts of slope suitable for engineering application are drawn. Moreover, the studies show that:(1) the average method yields similar results as that of the polardiameter method;(2) compared with the traditional uniform strength-reduction(USR) technique, the slope stability obtained using the DSR techniquetends to be more unsafe; and(3) for a slope in the critical LE state, the strength parameter φ, i.e., internal friction angle, has greater contribution on the slope stability than the strength parameters c, i.e., cohesion. 展开更多
关键词 SLOPE STABILITY Nonlinear Mohr-Coulomb (M-C) criterion DOUBLE strength-reduction(DSR) technique SLOPE COMPREHENSIVE factor ofSafety (FOS) STABILITY charts
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Investigation of Oxidation-Reduction Properties of Growing Mediums for Cell Culture of Mammals under the Effect of Cosmo-Geophysical Factors 被引量:1
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作者 S. S. Moisa V. V. Tsetlin A. N. Velikanov 《Journal of Biomedical Science and Engineering》 2019年第2期85-91,共7页
In model experiments were studied the effect of cosmo-geophysical factors of environment (hypomagnetic conditions during 2 days ≈ 1 mkT;electromagnetic irradiation (10 min - 2 MHz with amplitude 5 V/m and power 30 mk... In model experiments were studied the effect of cosmo-geophysical factors of environment (hypomagnetic conditions during 2 days ≈ 1 mkT;electromagnetic irradiation (10 min - 2 MHz with amplitude 5 V/m and power 30 mkVt, background 2 - 4 mkVt), γ-quantum (10 min—from the source 137Cs) and its combined effect on the physic-chemical properties (ORP and pH) of growing medium for cell culture of mammals as nutrition medium 199 (PanEco, Russia). It was used a clear solution of medium (solution 1) and with the adding of 10% embryo bull serum—model of bio-medium (solution 2). Hypomagnetic conditions evoked the decreasing of ORP and pH value in both solutions, electromagnetic irradiation in the solution 1 which evoked the decreasing of ORP and the increasing of pH value, and in the solution 2, on the contrary, the increasing of ORP with the unchanging pH value. γ-radiation sharply decreased ORP value and didn’t change pH in solution 1, i.e. the reduction properties increased. There is insignificant increasing of ORP value and the decreasing of pH is noted in the solution 2, that it is characterized with the increasing of oxidative properties of solution. Under the combined effect of hypomagnetic conditions and electromagnetic irradiation, the values of investigating parameters in the solution 1 decreased and in the solution 2 increased. It was observed acute decreasing of ORP value in both solutions under the combined effect of hypomagnetic conditions and γ-radiation, i.e. the reductive properties of the solutions increased sharply. In this the concentration H+ significantly decreased, (p γ-radiation led to the decreasing of ORP and pH values in both solutions. Thus, the studying factors significantly change the oxidation-reduction properties of growing mediums. The investigation of the processes in biological mediums plays the important role in the assessment of environment effect during the flight in inter-planet space. 展开更多
关键词 Cosmo-Geophysical factors GROWING Mediums for Cell Culture of MAMMALS Oxidation-reduction Properties
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Retrospective Analysis of Treatment Results by Non-Invasive Radiofrequency (RF) Device with Standard and High Voltage RF Electrical Pulses Coupled with Suction for Fat Reduction and Cellulite Improvement
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作者 Judith Hellman R. Stephen Mulholland 《Journal of Cosmetics, Dermatological Sciences and Applications》 2021年第4期279-292,共14页
<strong>Introduction:</strong> The growing demand for non-surgical, non-invasive procedures for fat and circumference reduction and for cellulite treatments has led to the development of various energy-bas... <strong>Introduction:</strong> The growing demand for non-surgical, non-invasive procedures for fat and circumference reduction and for cellulite treatments has led to the development of various energy-based technologies. Bi-polar radiofrequency (RF) technology combined with additional technologies, such as vacuum, massage or infrared (IR) light is widely used in various body contouring treatments in the medical aesthetic market. The current study is based on a retrospective efficacy analysis of an RF device, combining two RF modalities, coupled with suction. <strong>Methods:</strong> Representative treatment outcomes, documented in photographs taken at baseline and post-treatment were gathered from several clinics. Photos of the various treatment areas were evaluated by independent evaluators for cellulite and contour improvement. <strong>Results:</strong> Before and after photographs were gathered from 31 patients treated in different clinics. Analysis was carried out on different body areas such as thighs, abdomen, back, buttocks and arms and analyzed by two independent evaluators. Scoring was performed according to the Global Aesthetic Improvement Scale (GAIS) scale and indicated an overall improvement in the contour of all treated body areas. In cellulite cases, improved appearance according to the cellulite grading scale was noted. <strong>Conclusion:</strong> This retrospective analysis supports the device’s efficacy for fat and circumferences reduction and cellulite improvement. The device’s unique specifications contribute to treatment safety and efficacy which is highly tolerable by the patients. 展开更多
关键词 Noninvasive Radiofrequency rf Fat reduction Adipocytes Apoptosis Adi-pose Tissue Fat reduction Cellulite Improvement ELECTROPORATION
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Stability and Influence Factors Analysis of Wharf Slope on Slippery Stratum
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作者 LI Peng-fei LIU Ming-wei DAI Ru-lin 《International Journal of Technology Management》 2014年第7期34-37,共4页
关键词 边坡稳定性 码头 影响因素 地层 有限元强度折减法 水位变化 极限平衡法 三峡库区
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