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Icon memory research under different time pressures and icon quantities based on event-related potential 被引量:5
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作者 牛亚峰 薛澄岐 +3 位作者 李雪松 李晶 王海燕 金涛 《Journal of Southeast University(English Edition)》 EI CAS 2014年第1期45-50,共6页
In order to obtain related brain electrical components and neural bases of physiology assessment of icon elements in a digital human-computer interface the modified sample-delay matching task experimental paradigm is ... In order to obtain related brain electrical components and neural bases of physiology assessment of icon elements in a digital human-computer interface the modified sample-delay matching task experimental paradigm is used under different time pressures 4 000 and 2 000 ms and different icon quantities three five and ten icons on icon memory based on event-related potential ERP technology.Experimental results demonstrate that P300 has significant volatility changes and the maximum amplitude around the middle line of the parietal area PZ and P200 has obvious volatility changes around the middle line of the frontal and central area FCZ during icon cognition.P300 and P200 amplitudes increase as tasks become more difficult.Thus P300 latency is positively correlated with task difficulty. ERP research on the characteristics of icon memory will be an important reference standard in guiding user neurocognitive behavior and physiology assessment on interface usability. 展开更多
关键词 time pressure icon quantity event-related potential ERP
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Effects of shifting time on pressure impact in hydraulic systems 被引量:5
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作者 ZHU Zhen-cai CHEN Guo-an 《Journal of Central South University of Technology》 2005年第z1期217-221,共5页
The limitations in existing measures for absorbing pressure impact in hydraulic systems were summarized in this paper. Based on the forming principle of the oil in a hydrostatic closed pressure chamber, the underlying... The limitations in existing measures for absorbing pressure impact in hydraulic systems were summarized in this paper. Based on the forming principle of the oil in a hydrostatic closed pressure chamber, the underlying reasons of the pressure impact were analyzed theoretically, the intrinsic laws that the extent of the pressure impact in hydraulic oil lines are affected by some factors, such as oil elastic modulus, oil line's geometrical volume, and changing rate of oil volume versus time etc, were discussed. Experimental investigations into pressure impact in all pressure chambers because of shifting were conducted under different working conditions by employing a special experimental system. The effects of shifting time on pressure impact were studied. A new concept with universal meaning, i.e. optimal shifting time, and its characterizing parameter and the methods of shifting at optimal shifting time were also proposed. The results show that shifting time lag △t is of rationality and maneuverablility. The higher the working pressure, the shorter the shifting time. 展开更多
关键词 HYDRAULIC system SHIFTING time pressure impact EXPERIMENT LAW
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The Relationship between Time Pressure and Burnout Syndrome: A Cross-Sectional Survey among Jordanian Nurses 被引量:2
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作者 Muhammad W. Darawad Hani Nawafleh +2 位作者 Mahmoud Maharmeh Ayman M. Hamdan-Mansour Saleh N. Azzeghaiby 《Health》 2015年第1期14-22,共9页
Burnout among nurses is well documented in literature. Precursors of burnout such as time pressure need further study for better understanding. In Jordan literature, studies regarding time pressure and burnout among J... Burnout among nurses is well documented in literature. Precursors of burnout such as time pressure need further study for better understanding. In Jordan literature, studies regarding time pressure and burnout among Jordanian nurses are scarce. This study aimed to 1) evaluate the relationship between time pressure and burnout, and 2) identify participants’ characteristics that may have relationship with time pressure and burnout. A descriptive correlational design was utilized using a self-reported cross-sectional survey to collect data from 175 Jordanian nurses. Participants reported high level of time pressure (24.8 out of 126) and burnout (72.9 out of 126). Time pressure was correlated with emotional exhaustion and depersonalization (r = 0.561, 0.491, P < 0.01, respectively). Burnout was highest on the emotional exhaustion (72%) compared to 53.9% for depersonalization and 49.2% for personal achievement. Depersonalization showed the most frequent correlation with participants’ characteristics. Burnout was found to be common among Jordanian nurses, and time pressure is a precursor of this phenomenon, giving rise to the consequences on both patients’ and nurses’ health. Healthcare administrators have to modify the nursing work environment to be less stressful and more appealing to overcome the causes of nurses’ burnout. 展开更多
关键词 time pressure BURNOUT WORK Environment Nurses JORDAN
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Particle residence time distribution and axial dispersion coefficient in a pressurized circulating fluidized bed by using multiphase particle-in-cell simulation
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作者 Jinnan Guo Daoyin Liu +2 位作者 Jiliang Ma Cai Liang Xiaoping Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期167-176,共10页
The particle residence time distribution(RTD)and axial dispersion coefficient are key parameters for the design and operation of a pressurized circulating fluidized bed(PCFB).In this study,the effects of pressure(0.1-... The particle residence time distribution(RTD)and axial dispersion coefficient are key parameters for the design and operation of a pressurized circulating fluidized bed(PCFB).In this study,the effects of pressure(0.1-0.6 MPa),fluidizing gas velocity(2-7 m·s^(-1)),and solid circulation rate(10-90 kg·m^(-2)·s^(-1))on particle RTD and axial dispersion coefficient in a PCFB are numerically investigated based on the multiphase particle-in-cell(MP-PIC)method.The details of the gas-solid flow behaviors of PCFB are revealed.Based on the gas-solid flow pattern,the particles tend to move more orderly under elevated pressures.With an increase in either fluidizing gas velocity or solid circulation rate,the mean residence time of particles decreases while the axial dispersion coefficient increases.With an increase in pressure,the core-annulus flow is strengthened,which leads to a wider shape of the particle RTD curve and a larger mean particle residence time.The back-mixing of particles increases with increasing pressure,resulting in an increase in the axial dispersion coefficient. 展开更多
关键词 pressurized circulating fluidized bed MP-PIC method Residence time distribution Axial dispersion coefficient
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Effect of pulse voltage rising time on discharge characteristics of a helium-air plasma at atmospheric pressure 被引量:1
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作者 Muyang QIAN Gui LI +4 位作者 Sanqiu LIU Yu ZHANG Shan LI Zebin LIN Dezhen WANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第6期102-107,共6页
In this paper,the influence of voltage rising time on a pulsed-dc helium-air plasma at atmospheric pressure is numerically simulated.Simulation results show that as the voltage rising time increases from 10 ns to 30 n... In this paper,the influence of voltage rising time on a pulsed-dc helium-air plasma at atmospheric pressure is numerically simulated.Simulation results show that as the voltage rising time increases from 10 ns to 30 ns,there is a decrease in the discharge current,namely 0.052 A when the voltage rising time is 10 ns and 0.038 A when the voltage rising time is 30 ns.Additionally,a shorter voltage rising time results in a faster breakdown,a more rapidly rising current waveform,and a higher breakdown voltage.Furthermore,the basic parameters of the streamer discharge also increase with voltage rise rate,which is ascribed to the fact that more energetic electrons are produced in a shorter voltage rising time.Therefore,a pulsed-dc voltage with a short rising time is desirable for efficient production of nonequilibrium atmospheric pressure plasma discharge. 展开更多
关键词 atmospheric pressure plasma discharge voltage rising time numerical simulation
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Pressure and Time Dependences of the Supercooled Liquid-to-Liquid Transition in Sulfur 被引量:1
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作者 张豆豆 刘秀茹 +1 位作者 何竹 洪时明 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第2期83-86,共4页
Thermal behavior of bulk amorphous sulfur is investigated by in situ temperature measurements at high pressures of 0.9, 1.4 and 2.1 GPa, and under different heating rates of 8, 10 and 12K/min at 0.9 GPa. The results s... Thermal behavior of bulk amorphous sulfur is investigated by in situ temperature measurements at high pressures of 0.9, 1.4 and 2.1 GPa, and under different heating rates of 8, 10 and 12K/min at 0.9 GPa. The results show that the onset temperature of the transition from the supercooled Hquid to the liquid state for sulfur increases with the pressure and the heating rate. It is deduced that the transition does not follow the Clapeyron equation, indicating considerable coupling of the molecular structure change in the transition. Along with the data at ambient pressure and high pressure, we present a dynamic diagram to demonstrate the relationship between the amorphous solid, supercooled liquid, liquid, and crystal phases of sulfur, and suggest an experimental approach to establish pressure-temperature-time transition diagrams for supercooled liquid and liquid. 展开更多
关键词 of on IT pressure and time Dependences of the Supercooled Liquid-to-Liquid Transition in Sulfur in that for IS
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Time history of seismic earth pressure response from gravity retaining wall based on energy dissipation 被引量:1
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作者 QU Hong-lue DENG Yuan-yuan +2 位作者 GAO Ya-nan HUANG Xue ZHANG Zhe 《Journal of Mountain Science》 SCIE CSCD 2022年第2期578-590,共13页
The seismic design of gravity retaining walls is based mostly on the pseudo static method.The seismic earth pressure is assumed to be a constant without considering the wave traveling effect when the seismic wave prop... The seismic design of gravity retaining walls is based mostly on the pseudo static method.The seismic earth pressure is assumed to be a constant without considering the wave traveling effect when the seismic wave propagates through the slope.However,under continuous ground motion,the actual earth pressure on the retaining wall varies with time.The present seismic earth pressure calculation method yields results that differ significantly from the actual scenario.Considering this,a slip surface curve was assumed in this study.It is more suitable for engineering practice.In addition,a theoretical calculation model based on energy dissipation was established.The time history of seismic earth pressure response under continuous ground motion was calculated using the equilibrium equation between the external power and the internal energy dissipation power of the sliding soil wedge.It can more effectively reflect the stress scenario of a retaining wall under seismic conditions.To verify the applicability of the proposed approach,a large-scale shaking table test was conducted,and the time history of the seismic earth pressure response obtained from the experiment was compared with the calculation results.The results show that the proposed approach is applicable to the calculation of the time history of seismic earth pressure response of gravity retaining walls.This lays the foundation for the seismic design of retaining structures by using dynamic time history. 展开更多
关键词 Energy dissipation time history of seismic earth pressure response Slip surface curve Gravity retaining wall Shaking table test
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Effect of working time on environmental pressures:empirical evidence from EU-15,1970-2010
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作者 Qinglong Shao 《Chinese Journal of Population,Resources and Environment》 2015年第3期231-239,共9页
There is growing interest in the correlation between working time and environmental pressures,but prior empirical studies mostly focused on static methodologies.This article used dynamic panel regression approaches to... There is growing interest in the correlation between working time and environmental pressures,but prior empirical studies mostly focused on static methodologies.This article used dynamic panel regression approaches to examine and compare the relationship among western,southern,and northern European countries over the period 1970-2010,and proved the existence of strongly significant relationships in all models.Furthermore,this article detected the relationship between working hours and environmental indicators(carbon emission and energy use) at different phases.We contribute to a further understanding of the environmental effects of the working time reduction policy by comparing the differences among various periods and country groups in a system generalized method of moments(GMM) dynamic framework. 展开更多
关键词 working time ENVIRONMENTAL pressure CARBON EMISSION system GMM
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Run by Run Control of Time-pressure Dispensing for Electronics Encapsulation 被引量:5
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作者 Cong-Ping Chen Han Ding 《International Journal of Automation and computing》 EI 2008年第4期419-424,共6页
To alleviate the influence of gas compressibility on the process performance of time-pressure dispensing for electronics encapsulation,a predictive model is developed based on power-law fluid to estimate the encapsula... To alleviate the influence of gas compressibility on the process performance of time-pressure dispensing for electronics encapsulation,a predictive model is developed based on power-law fluid to estimate the encapsulant amount dispensed.Based on the simple and effective model,a run by run (RbR) supervisory control scheme is delivered to compensate the variation resulting from gas volume change in the syringe.Both simulation and experiment have shown that the dispensing consistency has been greatly improved with the model-based RbR control strategy developed in this paper. 展开更多
关键词 time-pressure dispensing predictive model run by run (RbR) control electronics encapsulation.
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Modeling and Control of Time-pressure Dispensing for Semiconductor Manufacturing 被引量:5
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作者 Cong-Ping Chen Han-Xiong Li Han Ding 《International Journal of Automation and computing》 EI 2007年第4期422-427,共6页
To improve the consistency of the adhesive amount dispensed by the time-pressure dispenser for semiconductor manufacturing, a non-Newtonian fluid flow rate model is developed to represent and estimate the adhesive amo... To improve the consistency of the adhesive amount dispensed by the time-pressure dispenser for semiconductor manufacturing, a non-Newtonian fluid flow rate model is developed to represent and estimate the adhesive amount dispensed in each cycle. Taking account of gas compressibility, an intelligent model-based control strategy is proposed to compensate the deviation of adhesive amount dispensed from the desired one. Both simulations and experiments show that the dispensing consistency is greatly improved by using the model-based control strategy developed in this paper. 展开更多
关键词 time-pressure dispensing CONSISTENCY fluid flow rate model model-based control.
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Numerical Investigation of the Effect of Sorption Time on Coal Permeability and Gas Pressure
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作者 Yi Xue Faning Dang +1 位作者 Rongjian Li Fei Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2018年第6期345-358,共14页
Adsorption deformation significantly affects the seepage characteristics of coal.However,effect of sorption time on coal permeability and gas pressure has not been investigated systematically.In this study,the sorptio... Adsorption deformation significantly affects the seepage characteristics of coal.However,effect of sorption time on coal permeability and gas pressure has not been investigated systematically.In this study,the sorption experiment of coal samples is conducted to elaborate the importance of sorption equilibration time.Then a coupled coal deformation and gas flow model is established considering the sorption characteristic and permeability evolution.This coupled model is implemented through finite element method to analyze the effect of sorption time on coal permeability and gas pressure.The simulation results reveal that the gas pressure of the coal will change with the adsorption time.The fracture pressure maintains a high level while the matrix pressure is relatively low during the adsorption process.The sorption time has a great influence on the distribution of gas pressure.The smaller the adsorption time is,the lower the gas pressure becomes. 展开更多
关键词 PERMEABILITY POROSITY gas pressure ADSORPTION time
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Space-time analysis of the changing patterns of population pressure on the ecological environment in China 被引量:1
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作者 Dongqi Sun Jinliang Jiang +2 位作者 Jianbin Xu Liang Zhou Yi Hu 《Chinese Journal of Population,Resources and Environment》 2015年第4期341-348,共8页
This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China.We have collected sufficient data from the statistical yearbooks of 31 provincial administrat... This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China.We have collected sufficient data from the statistical yearbooks of 31 provincial administrative areas in 1990,1995,2000,2005,and 2010.Using a geographic information system(GIS) and relevant models,we analyzed the trend of the population pressure on ecological environment and the change of the gravity center of ecological environment quality.We conclude that:(1) generally,population pressure on the ecological environment in China was becoming higher during1990-2010,especially in some areas where the population and environment were in serious imbalance and the ecological environment experienced severe pollution;(2) during a certain period,population pressure on the ecological environment was becoming lower in some areas,but the ecological environment was getting worse;(3) the areas with super-high population pressure on the ecological environment were Beijing,Tianjin,and Shanghai;(4) the gravity center of population pressure on the ecological environment and the center of ecological environment quality move differently during the study time period,but the general trend was similar- both of them were moving from west to east.Based on the analysis,this paper also provides some policy suggestions on the control of ecological environment quality. 展开更多
关键词 Chinese POPULATION ECO-ENVIRONMENT ECO-ENVIRONMENTAL pressure CHANGING TREND SPACE-time analysis
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Local and Time Changes over a 66-Year Period and Annual Relocation of Saudi Arabian Subtropical High Pressure
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作者 Hasan Lashkari Ali Akbar Matkan Zainab Mohammadi 《Open Journal of Geology》 2016年第9期1080-1095,共16页
Saudi Arabian subtropical high pressure is a major system affecting general circulation of the atmosphere of west Asia. Its annual relocation affects the relocation of other systems in the area, such as Mediterranean ... Saudi Arabian subtropical high pressure is a major system affecting general circulation of the atmosphere of west Asia. Its annual relocation affects the relocation of other systems in the area, such as Mediterranean cyclones, Sudanese low pressure areas, and west wind waves. This system is known to relocate to the south and north in response to outward solar relocation, but the reasons behind its eastern and western relocation have not been studied thoroughly. The present study examined 1000 and 850 HPa levels over the course of 66 years (1948-2015) to determine a pattern of latitudinal and longitudinal relocation of the system using synoptic maps. The research showed that, after 2008, high pressure latitudinal and longitudinal swings were larger than in previous years and the annual high pressure relocation was not in concord with the apparent motion of the sun. At the onset of autumnal moderation, the high pressure core was positioned to the north of Saudi Arabia (22° - 30° north latitude and 42° - 50° south longitude). Southern movement continued until the end of March, when the core again relocated to the north. These relocations first occurred slowly, but the northern relocation occurred very quickly from May to June, such that the core moved northward 22° to 30°. After June, the core did not relocate much until the end of September. After September, it relocated strongly south in all time periods. It was noted that high pressure over Saudi Arabia had two cores from June to September in some years;in others the high pressure core was in southwestern Iran and Iraq. In still others, a southwest to northeast high pressure tab entered Iran from the southwest (Khuzestan) and continued northward with a core forming in the northern Caspian Sea. 展开更多
关键词 Analysis time and Local Change Subtropical High pressure Saudi Arabia
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Influences of Mixed Traffic Flow and Time Pressure on Mistake-Prone Driving Behaviors among Bus Drivers
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作者 Vu Van-Huy Hisashi Kubota 《Journal of Transportation Technologies》 2023年第3期389-410,共22页
Bus safety is a matter of great importance in many developing countries, with driving behaviors among bus drivers identified as a primary factor contributing to accidents. This concern is particularly amplified in mix... Bus safety is a matter of great importance in many developing countries, with driving behaviors among bus drivers identified as a primary factor contributing to accidents. This concern is particularly amplified in mixed traffic flow (MTF) environments with time pressure (TP). However, there is a lack of sufficient research exploring the relationships among these factors. This study consists of two papers that aim to investigate the impact of MTF environments with TP on the driving behaviors of bus drivers. While the first paper focuses on violated driving behaviors, this particular paper delves into mistake-prone driving behaviors (MDB). To collect data on MDB, as well as perceptions of MTF and TP, a questionnaire survey was implemented among bus drivers. Factor analyses were employed to create new measurements for validating MDB in MTF environments. The study utilized partial correlation and linear regression analyses with the Bayesian Model Averaging (BMA) method to explore the relationships between MDB and MTF/TP. The results revealed a modified scale for MDB. Two MTF factors and two TP factors were found to be significantly associated with MDB. A high presence of motorcycles and dangerous interactions among vehicles were not found to be associated with MDB among bus drivers. However, bus drivers who perceived motorcyclists as aggressive, considered road users’ traffic habits as unsafe, and perceived bus routes’ punctuality and organization as very strict were more likely to exhibit MDB. Moreover, the results from the three MDB predictive models demonstrated a positive impact of bus route organization on MDB among bus drivers. The study also examined various relationships between the socio-demographic characteristics of bus drivers and MDB. These findings are of practical significance in developing interventions aimed at reducing MDB among bus drivers operating in MTF environments with TP. 展开更多
关键词 Bus Safety Mistake-Prone Driving Behavior Mixed Traffic time pressure Factor Analyses Bayesian Model Averaging
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Real-Time Computer Analytical Application in Pressure Transient Analysis of Petroleum Reservoirs
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作者 Kanya Khatri Sadiq A. Shah +4 位作者 Agha F. H. Pathan Bilal Shams Ashfaque A. Memon Faisal Hussain Kanwal K. Pinjani 《International Journal of Geosciences》 2013年第8期1186-1192,共7页
Today with certainty, the petroleum industry is fostering sanguinely the fields’ development programs for the optimization of reservoir characterization through worth-full appliances of computer analysis techniques. ... Today with certainty, the petroleum industry is fostering sanguinely the fields’ development programs for the optimization of reservoir characterization through worth-full appliances of computer analysis techniques. The time element is of prime importance for optimistic petroleum development projects. Therefore, the frontline of “Real-time Analysis” is added into the applications of computer solving techniques for achieving and sketching up the real-time cost effectiveness in analyzing field development programs. It focuses on the phases of real-time well test data acquisition system, real-time secure access to the well test data either on field or in office and real-time data interpretation unit. This interface will yield the productive results for the field of reservoir’s pressure transient analysis and wells’ systems analysis by following the up-to-date preferred, accurate and effective well test analytical principles with modern real-time computer applications and techniques. It also lays emphasis for the comfort and reliability of data in creating best interpersonal working modes within a reputable and esteemed petroleum development organization. 展开更多
关键词 RESERVOIR pressure Transient REAL-time Analysis COMFORT COMPUTER Applications
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Pressure fluctuation and its influencing factors in circulating water pump 被引量:12
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作者 代翠 孔繁余 董亮 《Journal of Central South University》 SCIE EI CAS 2013年第1期149-155,共7页
In order to investigate the effect of sampling frequency and time on pressure fluctuations, the three-dimensional unsteady numerical simulations were conducted in a circulating water pump. Through comparison of turbul... In order to investigate the effect of sampling frequency and time on pressure fluctuations, the three-dimensional unsteady numerical simulations were conducted in a circulating water pump. Through comparison of turbulence models with hydraulic performance experiment, SST k-co model was confirmed to study the rational determination of sampling frequency and time better. The Fast Fourier Transform (FFT) technology was then adopted to process those fluctuating pressure signals obtained. On these bases, the characteristics of pressure fluctuations acting on the tongue were discussed. It is found that aliasing errors decrease at higher sampling frequency of 17 640 Hz, but not at a lower sampling frequency of 1 764 Hz. Correspondingly, an output frequency range ten-times wider is obtained at 17 640 Hz. Compared with 8R, when the sampling time is shorter, the amplitudes may be overvalued, and the frequencies and amplitudes of low-frequency fluctuations can not be well predicted. The frequencies at the tongue are in good agreement with the values calculated by formula and the frequency compositions less than the blade passing frequency are accurately predicted. 展开更多
关键词 circulating water pump turbulence model sampling frequency sampling time pressure fluctuation
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Model-scale tests to examine water pressures acting on potentially buoyant underground structures in clay strata 被引量:3
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作者 Zhisheng Ren Qixian Lu +2 位作者 Kaiwen Liu Pengpeng Ni Guoxiong Mei 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第3期861-872,共12页
Throughout the service life, underground structures are subjected to transient and sustained hydrostatic pressures. The reservoir impoundment results in an increase in water level, as well as hydraulic gradient,which ... Throughout the service life, underground structures are subjected to transient and sustained hydrostatic pressures. The reservoir impoundment results in an increase in water level, as well as hydraulic gradient,which can endanger the uplift performance of infrastructure. In uplift design, a reduction factor is often suggested for buoyant force acting on underground structures in clays due to the time lag effect.However, the mechanism of pore pressure generation in clays is not fully understood. This investigation presents a novel U-shaped test chamber to assess the pore pressure generation with time in the horizontal branch subjected to an increase in reservoir level in the left vertical branch. A mathematical model is developed to explain the time lag effect of pore pressure generation. The test program also involves the evaluation of uplift pressure acting on foundation model in the right vertical branch due to adjacent reservoir impoundment. It is found that the time lag effect of pore pressure generation in clays can be observed irrespective of hydraulic gradient, but a higher hydraulic gradient can lead to a faster response in pore pressure sensors. A reduction factor of 0.84-0.87 should be considered to reduce the conservatism of uplift design. 展开更多
关键词 Buoyant force Reservoir impoundment Pore pressure generation Reduction factor Uplift pressure time lag effect
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The effect of high-pressure and high-temperature drying treatments on the deresination ratio of Pinus massoniana 被引量:2
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作者 Jie YANG Hong-Bin WEI +1 位作者 Fan LI Song-Lin YI 《Forestry Studies in China》 CAS 2013年第1期76-80,共5页
This study investigated the possibility of using high-temperature and high-pressure schedules to treat Pinus massoniana wood in order to reduce its oil content. We discuss the effect of drying temperature, absolute pr... This study investigated the possibility of using high-temperature and high-pressure schedules to treat Pinus massoniana wood in order to reduce its oil content. We discuss the effect of drying temperature, absolute pressure and the holding time on the deresination ratio in R massoniana wood and establish a model for the deresination ratio as a function of drying temperature, absolute pressure and holding time. The results show that the deresination ratio in- creased from 7.14% to 87.04% when the temperature increased from 150 to 200℃, the absolute pressure from 0.1 to 0.6 MPa and the holding time from 1 to 3 h. The optimal model for the deresination ratio (Y) with drying temperature (t), absolute pressure (p) and holding time (r) is: Y = 0.284t + 113.424p + 3.518r - 42.486, with a coefficient of determina- tion (R2) of 0.930. Compared with drying temperature and holding time, absolute pressure plays the more significant role in the deresination process. This study could provide a theoretical basis to the practical production of R massoniana wood. 展开更多
关键词 deresination ratio high temperature high pressure holding time Pinus massoniana
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Temperature and Pressure Behaviours of Methanol, Acetonitrile/Water Mixtures on Chromatographic Systems 被引量:1
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作者 Talal Aburjai Muhammed Alzweiri Yusuf M. Al-Hiari 《American Journal of Analytical Chemistry》 2011年第8期934-937,共4页
Temperature and pressure were shown to vary significantly with solvent mixing, showing maxima at differ-ent solvent ratios. Acetonitrile/water mixing resulted in temperature reduction of solutions whereas metha-nol/wa... Temperature and pressure were shown to vary significantly with solvent mixing, showing maxima at differ-ent solvent ratios. Acetonitrile/water mixing resulted in temperature reduction of solutions whereas metha-nol/water mixing caused temperature increases. On the other hand, maximum recorded chromatographic pressure of acetonitrile:water mixtures occurred at a solvent ratio of 1:6 compared with methanol:water, which showed a maximum pressure at a solvent ratio of 1:1. These findings can be of use in stabilizing re-tention time shifts during HPLC-based studies associated with compound identification based on retention time such as analysis of complex mixtures. 展开更多
关键词 Retention time pressure TEMPERATURE METHANOL and ACETONITRILE
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Effect of Ilizarov external fixation combined with negative pressure sealing drainage and antibiotics in the treatment of infective tibial nonunion 被引量:1
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作者 Guang Li You-Qiang Wei +4 位作者 Qi-Fa Guo Hai-Yun Zhang Luosong Jiumei Zhong-Lin Lu Chang-Shuai Li 《Journal of Hainan Medical University》 2019年第22期37-41,共5页
Objective:Observation on the effect of Ilizarov external fixation combined with vacuum pressure sealing drainage and antibiotics in the treatment of infective tibial nonunion.Methods:79 patients with tibial infective ... Objective:Observation on the effect of Ilizarov external fixation combined with vacuum pressure sealing drainage and antibiotics in the treatment of infective tibial nonunion.Methods:79 patients with tibial infective nonunion who were treated in our hospital from August 2016 to August 2018 were divided into two groups according to random number table,with 39 patients in the control group treated with Ilizarov external fixation technology and 40 patients in the study group treated with vacuum pressure sealing drainage and antibiotics on the basis of the control group.Bone healing time and daily walking were recorded.Rasmussen score,serum intercellular adhesion molecule-1(ICAM-1)and IL-6 levels,lower limb Fugl-Meyer motor function score and lower limb BI index score were compared at different time.Results:The daily walking condition of the study group was significantly better than that of the control group(P<0.05),and the healing time of bone was significantly shorter than that of the control group(P<0.05);the Rasmussen score of the study group was higher than that of the control group at 1 month,6 months and 12 months after treatment(P<0.05);the levels of serum ICAM-1 and IL-6 in the two groups after treatment were lower than those before treatment(P<0.05),and the levels of serum ICAM-1 and IL-6 in the study group were lower than those in the control group after treatment(P<0.05).The lower limb Fugl-Meyer motor function score and lower limb BI index score of the two groups after treatment were higher than those before treatment(P<0.05),and the lower limb Fugl-Meyer motor function score and lower limb BI index score of the study group after treatment were higher than those of the control group(P<0.05).Conclusions:Ilizarov external fixation combined with vacuum pressure sealing drainage and antibiotics can promote the bone healing of patients with infective tibial nonunion,significantly improving their daily walking condition,alleviating inflammation,and recovering the knee joint function and lower limb function well. 展开更多
关键词 ILIZAROV external fixation technology vacuum pressure sealing drainage ANTIBIOTICS INFECTIVE tibial NONUNION bone healing time serum INTERCELLULAR adhesion MOLECULE-1 level
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