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Optimization of Extraction Conditions for Total Flavonoids from Fructus Aurantii Immaturus and Its Anti-UVB Radiation Activity
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作者 Xu CHANG Yanhui WANG +5 位作者 Ximing LIU Yunge MA Yunhao LIU Xiaobo CHEN Mengyao SUN Liyan LI 《Agricultural Biotechnology》 CAS 2023年第4期110-114,118,共6页
[Objectives]Optimum extraction conditions of total flavonoids from Fructus Aurantii Immaturus(TFFAI)and its resistance activity to ultraviolet radiation were investigated in present research.[Methods]The optimal extra... [Objectives]Optimum extraction conditions of total flavonoids from Fructus Aurantii Immaturus(TFFAI)and its resistance activity to ultraviolet radiation were investigated in present research.[Methods]The optimal extraction conditions of TFFAI were determined by single factor and orthogonal experiments,and the survival rate of TFFAI on HaCaT cells irradiated with UVB rays was investigated.It s antioxidant capacity was determined by ABTS.[Results]The results showed that the highest yield of TFFAI was obtained with 70%ethanol at a solid-to-liquid ratio of 1:50(w/v)and 40℃for 1.5 h by single-factor and orthogonal experiments.Total flavonoids(0.25-1.00 mg/ml)could significantly improve the survival rate of HaCaT cell line.Meanwhile,the maximum absorption peak of TFFAI was found at 283 nm,and in-vitro antioxidant experiment identified that TFFAI had a good clearance rate to ABTS.It suggestes that TFFAI could protect the cells from UVB damage by absorption of UVB rays and anti-oxidation.[Conclusions]TFFAI played a protective role on UVB irradiated cells through UVB ultraviolet absorption and antioxidant pathways. 展开更多
关键词 Fructus Aurantss Immaturus total flavonoids Optimization of extraction conditions UVB radiation resistance
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An SDL Design and Implementation of a Radiation Monitoring Network Using WCDMA
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作者 Ahmed M. Abbas Abdelhalim Zekry +1 位作者 Imbaby I. Mahmoud Hussein A. Elsayed 《通讯和计算机(中英文版)》 2012年第5期602-612,共11页
关键词 WCDMA 监测网络 SDL 设计 通用移动电信系统 辐射 监控单元 测量单位
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Ground-based Observations of Ultraviolet and Total Solar Radiation in Shenyang,Northeast China 被引量:2
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作者 GAO Qian HU LiWen +6 位作者 GONG HuiZhi GAO Na YU JiaMing WANG Yang CHU Chun YANG Hui LIU Yang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2011年第5期499-505,共7页
Objective This work explores the diurnal variation of Solar ultraviolet radiation (UVR) and total solar radiation (TSR) in northeast China,using daily observations of UVR and TSR in Shenyang.Methods UVR and TSR me... Objective This work explores the diurnal variation of Solar ultraviolet radiation (UVR) and total solar radiation (TSR) in northeast China,using daily observations of UVR and TSR in Shenyang.Methods UVR and TSR measurements were carried out from March 1st,2006 to December 31st,2009 in Shenyang,Liaoning province,China (41°51' N,123°27' E).Results Both TSR and UVR showed seasonal variation,reaching the highest levels in summer and the lowest in winter.They showed the greatest fluctuation in summer and autumn.The irradiance of TSR and UVR on clear days around the equinoxes and solstices increased substantially compared with the mean seasonal irradiance,especially in autumn.The whole day accumulated dose of UVR in winter was far less than that during the middle part of a summer day (i.e.between 10:00 and 14:00).It was also less than the accumulated summer dose of morning and afternoon (i.e.between 8:00 and 10:00 and 14:00 and 16:00).Conclusion The instant irradiance and daily accumulated amount of UVR are low in Shenyang,especially in autumn and winter.Thus concern about the health effects arising because shortage of UVR in northeast China is warranted. 展开更多
关键词 Ultraviolet radiation total sun radiation Broadband radiometer
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Total dose radiation response of modified commercial silicon-on-insulator materials with nitrogen implanted buried oxide 被引量:2
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作者 郑中山 刘忠立 +1 位作者 于芳 李宁 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期361-366,共6页
Nitrogen ions of various doses are implanted into the buried oxide (BOX) of commercial silicon-on-insulator (SOI) materials, and subsequent annealings are carried out at various temperatures. The total dose radiat... Nitrogen ions of various doses are implanted into the buried oxide (BOX) of commercial silicon-on-insulator (SOI) materials, and subsequent annealings are carried out at various temperatures. The total dose radiation responses of the nitrogen-implanted SOI wafers are characterized by the high frequency capacitance-voltage (C-V) technique after irradi- ation using a Co-60 source. It is found that there exist relatively complex relationships between the radiation hardness of the nitrogen implanted BOX and the nitrogen implantation dose at different irradiation doses. The experimental results also suggest that a lower dose nitrogen implantation and a higher post-implantation annealing temperature are suitable for improving the radiation hardness of SOI wafer. Based on the measured C V data, secondary ion mass spectrometry (SIMS), and Fourier transform infrared (FTIR) spectroscopy, the total dose responses of the nitrogen-implanted SOI wafers are discussed. 展开更多
关键词 SILICON-ON-INSULATOR total dose radiation hardness nitrogen implantation
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Effects of solar radiation and fine roots on suction of Amorpha fruticose-vegetated soil
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作者 GUO Han-qing CHEN Xiao-qing +4 位作者 SONG Dong-ri MU Qing-yi SADEGHI Hamed JIANG Hao LV Ming 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1790-1804,共15页
The thickness of shallow landslides is generally less than 2 m,which is of the same order of magnitude as the growth range of vegetation roots.Vegetation roots can improve the stability of shallow soil through mechani... The thickness of shallow landslides is generally less than 2 m,which is of the same order of magnitude as the growth range of vegetation roots.Vegetation roots can improve the stability of shallow soil through mechanical and hydraulic effects.Therefore,the landslide process is closely related to the plant roots growing on the slope surface.Plant roots play a dominant role in the regulation of soil suction through solar radiation induced transpiration.However,little is known about the correlation between cumulative solar radiation and soil suction.Moreover,the specific effects of fine roots on the suction distribution are not clear in most previous studies.In this study,a vegetated soil of a drought-tolerant and water-tolerant shrub,namely Amorpha fruticose,was adopted.The suction and volumetric water content of bare and vegetated soils were monitored under natural conditions for 4 months.The results demonstrate that there is a nearly linear relationship between cumulative solar radiation and suction ranging from zero to 100 kPa.Regarding the modeling of the soil-plant-atmosphere interactions,this relationship could serve a significant role in calculating the root water uptake under given solar radiation conditions.In addition,higher suctions were observed at the lower layer of the vegetated soil than those at the middle layer,which is different from the results of vegetated soil from previous investigations.This is due to the fact that the root area index(RAI)of fine roots at the lower layer is twice that of the middle layer.Importantly,the higher concentration of fine roots at the lower layer of vegetated soil sample resembles the root distribution of shrub near the soil-bedrock interface on shallow bedrock landslides.The fine roots would increase soil suction through transpiration,and hence reduce the permeability and increase shear strength of landslides.Eventually,these new findings serve as a preliminary step on the evaluation of the stability of this common type of landslides. 展开更多
关键词 Field monitoring Fine roots Solar radiation SUCTION Shallow bedrock landslide
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Study of total ionizing dose radiation effects on enclosed gate transistors in a commercial CMOS technology 被引量:1
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作者 李冬梅 王志华 +1 位作者 皇甫丽英 勾秋静 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第12期3760-3765,共6页
This paper studies the total ionizing dose radiation effects on MOS (metal-oxide-semiconductor) transistors with normal and enclosed gate layout in a standard commercial CMOS (compensate MOS) bulk process. The lea... This paper studies the total ionizing dose radiation effects on MOS (metal-oxide-semiconductor) transistors with normal and enclosed gate layout in a standard commercial CMOS (compensate MOS) bulk process. The leakage current, threshold voltage shift, and transconductance of the devices were monitored before and after γ-ray irradiation. The parameters of the devices with different layout under different bias condition during irradiation at different total dose are investigated. The results show that the enclosed layout not only effectively eliminates the leakage but also improves the performance of threshold voltage and transconductance for NMOS (n-type channel MOS) transistors. The experimental results also indicate that analogue bias during irradiation is the worst case for enclosed gate NMOS. There is no evident different behaviour observed between normal PMOS (p-type channel MOS) transistors and enclosed gate PMOS transistors. 展开更多
关键词 MOS transistors radiation effects total dose layout
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Effects of cloud,atmospheric water vapor,and dust on photosynthetically active radiation and total solar radiation in a Mongolian grassland 被引量:1
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作者 Tserenpurev BAT-OYUN Masato SHINODA Mitsuru TSUBOn 《Journal of Arid Land》 SCIE 2012年第4期349-356,共8页
Photosynthetically active radiation (PAR) is an important input parameter for estimating plant produc- tivity due to its key role in the growth and development of plants. However, a worldwide routine network for sys... Photosynthetically active radiation (PAR) is an important input parameter for estimating plant produc- tivity due to its key role in the growth and development of plants. However, a worldwide routine network for sys- tematic PAR measurements is not yet established, and PAR is often calculated as a constant fraction of total solar radiation (SR). Although the ratio of PAR to SR (PAR/SR) has been reported from many places, few studies have been performed for dry regions. The present study was therefore carried out in an arid region of Mongolia to obtain PAP-JSR and examine its dependency on sky clearness (the clearness index), water vapor in the atmosphere and aeolian dust. Continuous measurements of PAR and SR were taken every one second using quantum and pyranometer sensors, respectively, and the readings were averaged and recorded at intervals of 30 minutes for a period of 12 months. The lowest monthly mean daily PAR/SR occurred in April (0.420), while the highest ratio was observed in July (0.459). Mean daily PAR/SR during plant growing season (May-August) was estimated to be 0.442, which could be useful for modeling plant productivity in the study area. The annual mean daily PAR/SR (0.435) was lower than the values reported in many previous studies. This difference could be explained with the regional variation in climate: i.e. drier climatic condition in the study area. PAR/SR was negatively correlated with the clearness index (r= -0.36, P〈0.001), but positively with atmospheric water vapor pressure (r=0.47, P〈0.001). The average PAR/SR was significantly lower (P=0.02) on the dusty days compared to the non-dust days. Water vapor in the atmosphere was shown to be the strongest factor in the variation of PAR/SR. This is the first study examining PAR/SR under a semi-arid condition in Mongolia. 展开更多
关键词 clearness index dust storm photosynthetically active radiation total solar radiation water vapor pressure
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Numerical Experiment of Combined Infrared and Ultraviolet Radiation Remote Sensing to Determine the Profile and Total Content of Atmospheric Ozone 被引量:1
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作者 程明虎 石广玉 周秀骥 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第3期305-319,共15页
A new remote sensing method is described to determine the vertical distribution and total content of atmospheric ozone. The method combines surface infrared, satellite infrared and ultraviolet channels. The width of t... A new remote sensing method is described to determine the vertical distribution and total content of atmospheric ozone. The method combines surface infrared, satellite infrared and ultraviolet channels. The width of the infrared channels is 0.01 cm-1, less than Lorentz half-width at the earth's surface, rather than the present width, because these channels can obtain information about variations in the ozone profile below the profile main-peak. The numerical experiments show that the method has a satisfactory precision in determining total ozone content, just about I percent error, and vertical distribution from the earth to 65 km space. In addition, some semi-analysis functions lor calculating backscattered ultraviolet and a relaxation equation are described in this paper. 展开更多
关键词 FIGURE SHOW Numerical Experiment of Combined Infrared and Ultraviolet radiation Remote Sensing to Determine the Profile and total Content of Atmospheric Ozone
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Total dose radiation characteristics of n-channel MOSFETs fabricated using FIPOS technology 被引量:1
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作者 ZhuShi-Yang Gao-Jian-Xia 《Nuclear Science and Techniques》 SCIE CAS CSCD 1997年第3期170-173,共4页
TotaldoseradiationcharacteristicsofnchannelMOSFETsfabricatedusingFIPOStechnologyZhuShiYang,HuangYiPing,WuDon... TotaldoseradiationcharacteristicsofnchannelMOSFETsfabricatedusingFIPOStechnologyZhuShiYang,HuangYiPing,WuDongPing(Depart... 展开更多
关键词 多孔氧化硅 CMOS 总剂量 辐照特征
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Simple Analysis on Change Features of Total Solar Radiation in Sanjiang Plain
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作者 Na Hongyan Hou Fang +2 位作者 Lv Hongyu Guo Bing Zhao Mengran 《Meteorological and Environmental Research》 CAS 2017年第1期1-4,共4页
The yearly,quarterly,monthly and daily change tendencies of total solar radiation at Jiamusi station of Sanjiang Plain were analyzed by statistical approach such as linear tendency estimate with its hourly ground mete... The yearly,quarterly,monthly and daily change tendencies of total solar radiation at Jiamusi station of Sanjiang Plain were analyzed by statistical approach such as linear tendency estimate with its hourly ground meteorological observation data during 1986 to 2015.The research results indicated that the yearly tendency rate of total solar radiation was increasing obviously,with the velocity of 114.30 MJ/(m2·10 a),while the yearly total solar radiation was 3 667.28-4 935.88 MJ/m^2,and that of March to September was higher than the average.The summer total solar radiation was the most,followed by spring,and that of all the seasons increased except autumn which decreased.The daily total solar radiation increased rapidly from the last ten days of January and reached the peak at the end of June,while it plummeted from the beginning of September to the middle ten days of November,then tended to be gentle.The amount of 5-year total solar radiation was less after 1980s while it was more before1990s,and the total solar radiation was decreasing from 1996 to 2005 but on the contrary it kept increasing in recent ten years.Over the years the earliest record of solar radiation appeared at 05:00 and the latest at 20:00,and the daily variation of the hourly solar radiation got a normal distribution centered on 12:00 to 13:00. 展开更多
关键词 total solar radiation TENDENCY rate ABRUPT CHANGE of climate ABNORMAL years China
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Advances in Monitorinq Methods of Downward Surface Net Radiation
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作者 GUO Peng WU Fadong XU Liping 《Journal of Landscape Research》 2016年第4期77-81,共5页
Downward surface net radiation,the net energy of the earth's surface obtained through shortwave and longwave radiation process,is the main driving force for material and energy cycle in the whole earth system.In t... Downward surface net radiation,the net energy of the earth's surface obtained through shortwave and longwave radiation process,is the main driving force for material and energy cycle in the whole earth system.In this study,the main research results of monitoring methods of downward surface net radiation at home and abroad in recent decades have been summarized,and main remote sensing radiation products produced according to various sensors have been introduced.Moreover,the monitoring methods of downward shortwave and long-wave radiation have been discussed,and their principles,advantages and disadvantages have been analyzed to provide scientific references for further study of downward surface solar net radiation in future. 展开更多
关键词 Downward surface solar net radiation monitoring methods ADVANCES
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Predictive formulas expressing relationship between dose rate and survival time in total body irradiation in mice
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作者 Sung Jang Chung 《Journal of Biomedical Science and Engineering》 2011年第11期707-718,共12页
The Gompertz model is the long-time well-known mathematical model of exponential expression among mortality models in the literature that are used to describe mortality and survival data of a population. The death rat... The Gompertz model is the long-time well-known mathematical model of exponential expression among mortality models in the literature that are used to describe mortality and survival data of a population. The death rate of the “probacent” model developed by the author based on animal experiments, clinical applications and mathematical reasoning was applied to predict age-specific death rates in the US elderly population, 2001, and to express a relationship among dose rate, duration of exposure and mortality probability in total body irradiation in humans. The results of both studies revealed a remarkable agreement between “probacent”-formula-predicted and published-reported values of death rates in the US elderly population or mortality probabilities in total body irradiation in humans (p - value > 0.995 in χ2 test in each study). In this study, both the Gompertz and “probacent” models are applied to the Sacher’s comprehensive experimental data on survival times of mice daily exposed to various doses of total body irradiation until death occurs with an assumption that each of both models is applicable to the data. The purpose of this study is to construct general formulas expressing relationship between dose rate and survival time in total body irradiation in mice. In addition, it is attempted to test which model better fits the reported data. The results of the comparative study revealed that the “probacent” model not only fit the Sacher’s reported data but also remarkably better fit the reported data than the Gompertz model. The “probacent” model might be hopefully helpful in research in human tolerance to low dose rates for long durations of exposure in total body irradiation, and further in research in a variety of biomedical phenomena. 展开更多
关键词 LETHAL radiation DOSE total Body Irradiation Formula of SURVIVAL Time in MICE Dose-Survival Curve “Probacent” MODEL GOMPERTZ MODEL
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Monitoring Bridge Deformation Using Auto-Correlation Adjustment Technique for Total Station Observations
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作者 Ashraf Abd El-Wanis Beshr Mosbeh R. Kaloop 《Positioning》 2013年第1期1-7,共7页
Bridges are omnipresent in every society and they affect its human, social, ecological, economical and cultural aspects. This is why a durable and safe usage of bridges is an imperative goal of structural management. ... Bridges are omnipresent in every society and they affect its human, social, ecological, economical and cultural aspects. This is why a durable and safe usage of bridges is an imperative goal of structural management. Measurement and monitoring have an essential role in structural management. The benefits of the information obtained by monitoring are apparent in several domains. In deformation analysis, the functional relationship between the acting forces and the resulting deformations should be established. If time depending observations are given, a regression could be used as a functional model. In case of stochastic model uncorrelated observations with identical variance are assumed. Due to the high sampling rate, a small time difference arises between two observations. Thus the assumed stochastic model is not suitable. The calculation has to be effected by means of auto-correlated observations. This paper investigates an integrated monitoring system for the estimation of the deformation (i.e., static, quasi-static) behavior of bridges from total station observations and studies the effect of autocorrelation technique on the accuracy of the estimated parameters and variances. The results have shown that autocorrelation technique is reduced the standard deviation of X&Y-direction about 6.7% to 29.4% and 6.5% to 15.5% of the original value, respectively, but the situation was differ in Z direction;the standard deviation in vertical component Z was increased. 展开更多
关键词 monitoring total STATION Auto-Correlation BRIDGES DEFORMATION
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Relationship between Solar Activity, Total Ozone, and Solar Ultraviolet Radiation: Multifractal Analysis
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作者 Fumio Maruyama 《Journal of Applied Mathematics and Physics》 2022年第6期1898-1909,共12页
We investigated the relationship between solar activity, total ozone, and solar ultraviolet B (UV-B) radiation from the perspective of multi-fractality. Fractal properties are observed in the time series of the dynami... We investigated the relationship between solar activity, total ozone, and solar ultraviolet B (UV-B) radiation from the perspective of multi-fractality. Fractal properties are observed in the time series of the dynamics of complex systems. To detect the changes in fractality, we performed a multifractal analysis using a wavelet transform. The changes in fractality indicated that solar activity was closely related to the total ozone and that the total ozone had a strong effect on UV-B radiation. For high solar activity, the F10.7 flux and global total ozone exhibited monofractality. The F10.7 flux and total ozone also increased, and a change from multifractality to monofractality was observed. This corresponded to the formation of the order. The strong interactions between the solar flux and ozone occur during the high solar activity. In contrast, UV-B radiation increased and showed multifractality, when fluctuations in UV-B radiation became large. For low solar activity, the F10.7 flux and total ozone exhibited multifractality, and UV-B radiation exhibited monofractality. Hence, the change in fractality of the F10.7 flux and total ozone was the opposite of UV-B radiation. A significant change in fractality for F10.7 flux and SSN, which had a significant fluctuation and a slight change in fractality for UV-B radiation, and total ozone were identified. 展开更多
关键词 Solar Flux total Ozone UV-B radiation WAVELET MULTIFRACTAL
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Total Ionizing Dose Radiation Effects in the P-Type Polycrystalline Silicon Thin Film Transistors
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作者 刘远 刘凯 +4 位作者 陈荣盛 刘玉荣 恩云飞 李斌 方文啸 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第1期133-136,共4页
The total ionizing dose radiation effects in the polycrystalline silicon thin film transistors are studied. Transfer characteristics, high-frequency capacitance-voltage curves and low-frequency noises (LFN) are measur... The total ionizing dose radiation effects in the polycrystalline silicon thin film transistors are studied. Transfer characteristics, high-frequency capacitance-voltage curves and low-frequency noises (LFN) are measured before and after radiation. The experimental results show that threshold voltage and hole-field-effect mobility decrease, while sub-threshold swing and low-frequency noise increase with the increase of the total dose. The contributions of radiation induced interface states and oxide trapped charges to the shift of threshold voltage are also estimated. Furthermore, spatial distributions of oxide trapped charges before and after radiation are extracted based on the LFN measurements. 展开更多
关键词 total Ionizing Dose radiation Effects in the P-Type Polycrystalline Silicon Thin Film Transistors SIO
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Total dose radiation effects of pressure sensors fabricated on Unibond-SOI materials
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作者 ZHUShi-Yang HUANGYi-Ping 《Nuclear Science and Techniques》 SCIE CAS CSCD 2001年第3期209-214,共6页
Piezoresistive pressure sensors with a twin-island structure were suc- cessfully fabricated using high quality Unibond-SOI (On Insulator) materials. Since the piezoresistors were structured by the single crystalline s... Piezoresistive pressure sensors with a twin-island structure were suc- cessfully fabricated using high quality Unibond-SOI (On Insulator) materials. Since the piezoresistors were structured by the single crystalline silicon overlayer of the SOI wafer and were totally isolated by the buried SiO2. the sensors are radiation-hard. The sensitivity and the linearity of the pressure sensors keep their original values after being irradiated by 60Co γ-rays up to 2.3×104Gy (H2O). However, the offset voltage of the sensor has a slight drift, increasing with the radiation dose. The absolute value of the offset voltage deviation depends on the pressure sensor itself. For comparison, corresponding polysilicon pressure sensors were fabricated using the similar process and irradiated at the same condition. 展开更多
关键词 半导体集成电路 SOI材料 大剂量辐照效应
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Diurnal Variations in Solar Ultraviolet Radiation at Typical Anatomical Sites 被引量:4
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作者 LI-WEN HU QIAN GAO +5 位作者 WEN-YING XU YANG WANG HUI-ZHI GONG GUO-QING DONG JING-HAI LI AND YANG LIU 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2010年第3期234-243,共10页
Objective Solar ultraviolet (UV) radiation is an important environmental factor that affects human health. The understanding of diurnal variations of UV radiation at anatomical sites may be helpful in developing way... Objective Solar ultraviolet (UV) radiation is an important environmental factor that affects human health. The understanding of diurnal variations of UV radiation at anatomical sites may be helpful in developing ways to protect humans from the harmful effects of UV radiation. Methods In order to characterize the diurnal variations, the UV exposure values were measured at 30 min intervals by using Solar-UV Sensors and a rotating manikin in Shenyang city of China (41°51'N, 123°27%). Measurement data for four representative days (in each of the four seasons respectively) were analyzed. Results The diurnal variations in solar UV radiation at the shoulder, the forehead and the chest were similar to those associated with a horizontal control measurement. However, the diurnal variations at the eye and the cheek exhibited bimodal distributions with two peaks in spring, summer and autumn, and a unimodal distribution in winter. The UV exposure peaks at the eye and the cheek were measured at solar elevation angles (SEA) of about 30° and 40°, respectively. Conclusion The protection of some anatomical sites such as the eye from high UV exposure should not be focused solely on the periods before and after noon, especially in the places and seasons with high SEA. 展开更多
关键词 Ultraviolet radiation EXPOSURE monitorS radiation dose
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Synergistic effects of total ionizing dose and radiated electromagnetic interference on analog-to-digital converter 被引量:3
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作者 Ping Wu Lin Wen +3 位作者 Zhi-Qian Xu Yun-Sheng Jiang Qi Guo Cui Meng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第3期172-180,共9页
The influence of combined total ionization dose(TID)and radiated electromagnetic interference(EMI)in a commercial analog-to-digital converter(ADC)was studied.The degradation of the direct-current response,the static p... The influence of combined total ionization dose(TID)and radiated electromagnetic interference(EMI)in a commercial analog-to-digital converter(ADC)was studied.The degradation of the direct-current response,the static parameters,and the dynamic parameters caused by the TID and EMI separately and synergistically is presented.The experimental results demonstrate that the increase in TID intensifies data error and the signal-tonoise ratio(SNR)degradation caused by radiated EMI.The cumulative distribution function of EMI failure with respect to data error and SNR with different TIDs was extracted.The decreasing trend of the threshold was acquired with a small sample size of five for each TID group.The result indicates that the ADC is more sensitive in a compound radiation environment. 展开更多
关键词 Integrated circuit total ionizing dose Electromagnetic radiation Synergistic effect Combined environment
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Non-contact monitoring and analysis system for tunnel surrounding rock deformation of underground engineering 被引量:1
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作者 YANG Song-lin, WANG Bin, JI Sheng-yue, LIU Wei-ning, SHI Hong-yun (Beijing Jiaotong University, Beijing 100044, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期96-99,共4页
It is very important to monitor surrounding rock deformation in tunnel construction. The principle, function, development and application of the system composed of a total station and computer for monitoring and analy... It is very important to monitor surrounding rock deformation in tunnel construction. The principle, function, development and application of the system composed of a total station and computer for monitoring and analyzing surrounding rock deformation were discussed. The new methods of two free station of 3D measurement and its mathematic adjustment mode were presented. The development of software for total station on-board and post for computer were also described. Without centering it and measuring its height, the total station controlled by the software on-board can fulfill the whole measurements to target points. Monitoring data can be processed by the post software and results of regression analysis, forecasting information of the tunnel surrounding rock deformation can be provided in time. The practical use shows that this system is practicable, highly accurate and efficient. It satisfies the needs of safety and information construction in tunnel construction of underground engineering. 展开更多
关键词 TUNNEL construction DEFORMATION of SURROUNDING ROCK total STATION NON-CONTACT monitoring data processing and analysis
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Influence of Solar Cycle Variations on Solar Spectral Radiation 被引量:1
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作者 Usama Ali Rahoma Rabab Helal 《Atmospheric and Climate Sciences》 2013年第1期47-54,共8页
The climatic changes associated with solar variability are largely caused by variations in total solar irradiance and solar spectral irradiance with solar activity. Thus the spectral composition of solar radiation is ... The climatic changes associated with solar variability are largely caused by variations in total solar irradiance and solar spectral irradiance with solar activity. Thus the spectral composition of solar radiation is crucial in determining atomspheric structure. The variations in solar spectrum depend on the varied solar spots. Recently, evidence for a strong effect of solar activity on terrestrial isolation on ground-based measurements carried out by the National Research Institute of Astronomy and Geophysics (NRIAG), Helwan, Egypt (lat. 29?52'N and long. 31?20'E) during (1990-2000) were presented. Specifically, a strong increase of terrestrial isolation with sunspot number as well as a decline of the solar spectrum with solar activity was reported. Daily measurements of the solar radiation between 280 nm and 2800 nm were made by Eppley Pyranometer and Pyrheliometer instruments. The decreasing at the range 280 - 530 nm and 530 - 630 nm are represented less than 50% of direct solar radiation and the stability of at the range 630 - 695 nm and 695 - 2800 nm it mean that;some of difference radiation is appear in diffused radiation which allow to height of the temperature as much as the largest associated with significance as it appears from the curves of relative humidity. 展开更多
关键词 SUNSPOT Number SOLAR radiation Spectrum total SOLAR IRRADIANCE Global SOLAR radiation Meteorologi-cal Parameter SOLAR CYCLE
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