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Relationships Between the Distribution of Relative Canopy Light Intensity and the Peach Yield and Quality 被引量:4
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作者 HE Feng-li WANG Fei +2 位作者 WEI Qin-ping WANG Xiao-wei ZHANG Qiang 《Agricultural Sciences in China》 CAS CSCD 2008年第3期297-302,共6页
The aim of the present experiment was to study the relationship between the distribution of relative light intensity in canopy and yield and quality of Wanmi peach. The optimum relative canopy light intensity was judg... The aim of the present experiment was to study the relationship between the distribution of relative light intensity in canopy and yield and quality of Wanmi peach. The optimum relative canopy light intensity was judged to be 36.3% for high quality peaches, when canopy volumes of Wanmi peach trees with a relative light intensity 〈 30% accounted for 7.7 and 47.9% of the total canopy volume in June and September, respectively. The canopy volume with a relative light intensity 〉 80% was 27.7 and 3.1% of the total canopy volume in June and September, respectively. Peach canopies were divided into 0.5 m × 0.5 m × 0.5 m cubes, with the relative light intensity being measured at different positions of the canopy during the growing season. Yield and fruit quality were also measured at these positions at harvest. The results showed that the relative light intensity decreased gradually from outside to inside and from top to bottom of the tree canopy. Fruit were mainly distributed in the upper and middle portions of the canopy, 1.5-3.0 m above ground. Regression results showed that single fruit weight and soluble solid content were positively related to relative light intensity. 展开更多
关键词 peach (Prunus persica L.) open-centered shape relative light intensity quality CANOPY
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The Distribution of Relative Light Intensity in a Peach Tree Canopy Affects Fruit Yield and Texture 被引量:1
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作者 Zhaoyuan WANG Qihang TIAN +4 位作者 Yong GUO Ruifeng CHANG Guojian LIU Hu CHEN Yonghong LI 《Agricultural Biotechnology》 CAS 2021年第3期141-144,共4页
Light is crucial to the uniform production of high-quality fruit since it is the driving force for leaf photosynthesis and hence overall plant nutrition.The objective of this study was to evaluate the relationship bet... Light is crucial to the uniform production of high-quality fruit since it is the driving force for leaf photosynthesis and hence overall plant nutrition.The objective of this study was to evaluate the relationship between the distribution of relative light intensity in the peach tree(Prunus persica)canopy and the yield and texture of peach fruits.The canopy of 7-year-old‘Qiuyan’was divided into cubical volumes and the relative light intensity distribution was measured for each cube,along with yield distribution and fruit textural properties at different growing times.The relative light intensity decreased gradually from outside to inside the canopy and from top to bottom.The yield distribution and the relative light intensity were clearly correlated.The percentage of the canopy receiving<30%relative light intensity was 49.07%in May,56.02%in June,and 58.95%in July,whereas the percentage receiving>80%relative light intensity was 32.72%,17.28%,and 10.96%,respectively.Consistent with this,peaches were found in the upper and middle portions of the canopy,within 1.5-3.0 m of the top.The regression equation showed that fruit texture index correlated significantly with relative light intensity.Relative light intensity is the main factor affecting peach yield and texture and must be above 41.83%for good peach quality.Orchardists should carefully plan summer pruning strategies to adjust the number and spatial distribution of branches accordingly. 展开更多
关键词 CANOPY Central leader form Relative light intensity Yield Texture property
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Characterization of the pairwise correlations in different quantum networks consisting of four-wave mixers and beamsplitters
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作者 祁健 忻俊 +1 位作者 王海龙 荆杰泰 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第7期153-160,共8页
We investigate the performances of the pairwise correlations(PCs) in different quantum networks consisting of fourwave mixers(FWMs) and beamsplitters(BSs). PCs with quantum correlation in different quantum netwo... We investigate the performances of the pairwise correlations(PCs) in different quantum networks consisting of fourwave mixers(FWMs) and beamsplitters(BSs). PCs with quantum correlation in different quantum networks can be verified by calculating the degree of relative intensity squeezing for any pair of all the output fields. More interestingly, the quantum correlation recovery and enhancement are present in the FWM+BS network and the repulsion effect phenomena(signal(idler)-frequency mode cannot be quantum correlated with the other two idler(signal)-frequency modes simultaneously)between the PCs with quantum correlation are predicted in the FWM + FWM and FWM + FWM + FWM networks. Our results presented here pave the way for the manipulation of the quantum correlation in quantum networks. 展开更多
关键词 pairwise correlation four-wave mixer degree of relative intensity squeezing quantum network
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Numerical simulation of four-wave mixing efficiency and its induced relative intensity noise
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作者 陈伟 孟洲 +1 位作者 周会娟 罗洪 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期515-519,共5页
Four-wave mixing, as well as its induced intensity noise, is harmful to wavelength division multiplexing systems. The efficiency and the relative intensity noise of four-wave mixing are numerically simulated for the t... Four-wave mixing, as well as its induced intensity noise, is harmful to wavelength division multiplexing systems. The efficiency and the relative intensity noise of four-wave mixing are numerically simulated for the two-wave and the three-wave fiber transmissions. It is found that the efficiency decreases with the increase of both the frequency spacing and the fiber length, which can be explained using the quasi-phase-matching condition. Furthermore, the relative intensity noise decreases with the increase of frequency spacing, while it increases with the increase of fiber length, which is due to the considerable power loss of the pump light. This investigation presents a good reference for the practical application of wavelength division multiplexing systems. 展开更多
关键词 four-wuve mixing EFFICIENCY relative intensity noise phase matching
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Confidence Intervals for Relative Intensity of Collaboration(RIC)Indicators
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作者 Joel Emanuel Fuchs Lawrence Smolinsky Ronald Rousseau 《Journal of Data and Information Science》 CSCD 2022年第4期5-15,共11页
Purpose:We aim to extend our investigations related to the Relative Intensity of Collaboration(RIC)indicator,by constructing a confidence interval for the obtained values.Design/methodology/approach:We use Mantel-Haen... Purpose:We aim to extend our investigations related to the Relative Intensity of Collaboration(RIC)indicator,by constructing a confidence interval for the obtained values.Design/methodology/approach:We use Mantel-Haenszel statistics as applied recently by Smolinsky,Klingenberg,and Marx.Findings:We obtain confidence intervals for the RIC indicatorResearch limitations:It is not obvious that data obtained from the Web of Science(or any other database)can be considered a random sample.Practical implications:We explain how to calculate confidence intervals.Bibliometric indicators are more often than not presented as precise values instead of an approximation depending on the database and the time of measurement.Our approach presents a suggestion to solve this problem.Originality/value:Our approach combines the statistics of binary categorical data and bibliometric studies of collaboration. 展开更多
关键词 Contingency tables Confidence intervals Relative intensity of collaboration(RIC) Mantel-Haenszel statistics Science of science
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Investigation on the intensity noise characteristics of the semiconductor ring laser
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作者 康泽新 蔡鑫伦 +3 位作者 温晓东 刘超 简水生 余思远 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期262-269,共8页
Based on the frequency-domain multimode theoretical model, detailed investigations on the noise characteristic of the semiconductor ring laser (SRL) are first performed in this paper. The comprehensive nonlinear ter... Based on the frequency-domain multimode theoretical model, detailed investigations on the noise characteristic of the semiconductor ring laser (SRL) are first performed in this paper. The comprehensive nonlinear terms related to the third order nonlinear susceptibility Z3 are included in this model; the Langevin noise sources for electric field and carrier density fluctuations are also taken into account. As the injection current increases, the SRL may present several operation regimes. Remarkable and unusual low frequency noise enhancement in the form of a broad low frequency tail extending all the way to the relaxation oscillation peak is observed in any of the operation regimes of SRLs. The influences of the backscattering coefficient on the relative intensity noise (RIN) spectrum in typical operation regimes are investigated in detail. 展开更多
关键词 semiconductor ring laser relative intensity noise low frequency noise enhancement
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L-shell x-ray fluorescence relative intensities for elements with 62≤Z≤83 at 18 keV and 23 keV by synchrotron radiation
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作者 M Alqadi S AL-Humaidi +1 位作者 H Alkhateeb F Alzoubi 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期270-273,共4页
The relative intensities of L-subshell x-ray fluorescence(XRF)for elements with atomic numbers 62≤Z≤83 were measured at two excitation energies,18 keV and 23 keV,using a synchrotron radiation source at a beamline of... The relative intensities of L-subshell x-ray fluorescence(XRF)for elements with atomic numbers 62≤Z≤83 were measured at two excitation energies,18 keV and 23 keV,using a synchrotron radiation source at a beamline of the Synchrotron Light Center for Experimental Science and Applications in the Middle East(SESAME),Jordan.The experimentally measured results of the relative intensities were compared with the calculated results using the subshell fluorescence yield and the Coster-Kronig transition probabilities recommended by Campbell and the values based on the Dirac-Hartree-Slater model by Puri.The experimental and theoretical results are in agreement.In this work,L XRF relative intensities for the elements Sm,Gd,Tb,Er,Ta,W,Re,Hg,Pb and Bi at energies of 18 keV and 23 keV were measured. 展开更多
关键词 L shell x-ray fluorescence(XRF) relative intensities synchrotron radiation
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Direct measurement of the three-dimensional distribution of leaf area density and light conditions in a mature oak stand by the cube method
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作者 Chiharu Migita Yukihiro Chiba Tanaka Kenzo 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1817-1827,共11页
Although the distributions of foliage and light play major roles in various forest functions,accurate,nondestructive measurement of these distributions is difficult due to the complexity of the canopy structure.To eva... Although the distributions of foliage and light play major roles in various forest functions,accurate,nondestructive measurement of these distributions is difficult due to the complexity of the canopy structure.To evaluate the foliage and light distributions directly and nondestructively in a mature oak stand,we used the cube method by dividing the forest canopy into small cubes(50 cm per side)and directly measured leaf area density(LAD,the total one-sided leaf area per unit volume,i.e.,cube)and relative irradiance(RI)within each cube.The distribution of LAD and of RI was highly heterogeneous,even at the same canopy height.This heterogeneity reflected the presence of foliage clusters associated with multiple forking branches.The relationship between cumulative LAD at the canopy surface and average RI followed the Beer-Lambert law.The mean light extinction coefficient(K)was 0.32.However,K was overestimated by more than double(0.80)when calculated based on the classical method using RI at the forest floor.This overestimation was caused by the lower RI due to light absorption by nonleaf plant parts below the canopy.Our findings on the complex foliage and light distributions in canopy layers should help improve the accuracy of RI and K measurements and thus more accurate predictions of environmental responses and forest functions. 展开更多
关键词 Beer-Lambert law Canopy structure Foliage cluster Leaf area density Leaf area index Relative light intensity
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Raman and infrared spectroscopic quantification of the carbonate concentration in K_(2)CO_(3)aqueous solutions with water as an internal standard 被引量:2
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作者 Yunlu Ma Wei Yan +1 位作者 Qiang Sun Xi Liu 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第2期1018-1030,共13页
Carbonate-bearing fluids widely exist in different geological settings,and play important roles in transporting some elements such as the rare earth elements.They may be trapped as large or small fluid inclusions(with... Carbonate-bearing fluids widely exist in different geological settings,and play important roles in transporting some elements such as the rare earth elements.They may be trapped as large or small fluid inclusions(with the size down to<1μm sometimes),and record critical physical-chemical signals for the formations of their host minerals.Spectroscopic methods like Raman spectroscopy and infrared spectroscopy have been proposed as effective methods to quantify the carbonate concentrations of these fluid inclusions.Although they have some great technical advantages over the conventional microthermometry method,there are still some technical difficulties to overcome before they can be routinely used to solve relevant geological problems.The typical limitations include their interlaboratory difference and poor performance on micro fluid inclusions.This study prepared standard ion-distilled water and K_(2)CO_(3)aqueous solutions at different molarities(from 0.5 to 5.5 mol/L),measured densities,collected Raman and infrared spectra,and explored correlations between the K_(2)CO_(3)molarity and the spectroscopic features at ambient P-T conditions.The result confirms that the Raman O-H stretching mode can be used as an internal standard to determine the carbonate concentrations despite some significant differences among the correlations,established in different laboratories,between the relative Raman intensity of the C-O symmetric stretching mode and that of the O-H stretching mode.It further reveals that the interlaboratory difference can be readily removed by performing one high-quality calibration experiment,provided that later quantifying analyses are conducted using the same Raman spectrometer with the same analytical conditions.Our infrared absorption data were collected from thin fluid films(thickness less than~2μm)formed by pressing the prepared solutions in a Microcompression Cell with two diamond-II plates.The data show that both the O-H stretching mode and the O-H bending mode can be used as internal standards to determine the carbonate concentrations.Since the IR signals of the C-O antisymmetric stretching vibration of the CO32ion,and the O-H stretching and bending vibrations from our thin films are very strong,their relative IR absorbance intensity,if well calibrated,can be used to investigate the micron-sized carbonate-bearing aqueous fluid inclusions.This study establishes the first calibration of this kind,which may have some applications.Additionally,our spectroscopic data suggest that as the K_(2)CO_(3)concentration increases the aqueous solution forms more large water molecule clusters via more intense hydrogen-bonding.This process may significantly alter the physical and chemical behavior of the fluids. 展开更多
关键词 Carbonate aqueous solution Micro fluid inclusion K_(2)CO_(3)concentration Relative Raman intensity Relative IR absorbance
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Hysteretic energy prediction method for mainshock-aftershock sequences 被引量:1
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作者 Zhai Changhai Ji Duofa +3 位作者 Wen Weiping Li Cuihua Lei Weidong Xie Lili 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2018年第2期277-291,共15页
Structures located in seismically active regions may be subjected to mainshock-aftershock(MSAS)sequences.present study selected two kinds of MSAS sequences,with one aftershock and two aftershocks,respectively.The af... Structures located in seismically active regions may be subjected to mainshock-aftershock(MSAS)sequences.present study selected two kinds of MSAS sequences,with one aftershock and two aftershocks,respectively.The aftershocksThe MSAS sequence with one aftershock exhibited a 10%to 30%hysteretic energy increase,whereas the MSAS sequence with two aftershocks presented a 20%to 40%hysteretic energy increase.Finally,a hysteretic energy prediction equation is proposed as a function of the vibration period,ductility value,and damping ratio to estimate hysteretic energy for mainshockaftershock sequences. 展开更多
关键词 hysteretic energy mainshock-aftershock sequences SDOF system relative intensity prediction equation
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Relations of intensity just noticeable difference to intensity of tonal bursts with various durations 被引量:1
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作者 LONG Zhangcai TANG Chaoqun (Department of Physics, Huazhong University of Science & Technology Wuhan 430074) YAO Qiuping (Hubei Provincial Institute of Measurement and Test Wuhan 430071) 《Chinese Journal of Acoustics》 2000年第2期114-122,共9页
The relations of intensity Just Noticeable Difference (JND) to intensity for tone bursts maybe,depend on signal durations according to Jont B.Allen's [J. Acoust. Soc. Am. 102 3, 1997, 3628--3646.]. The intensity j... The relations of intensity Just Noticeable Difference (JND) to intensity for tone bursts maybe,depend on signal durations according to Jont B.Allen's [J. Acoust. Soc. Am. 102 3, 1997, 3628--3646.]. The intensity just noticeable differences for tone bursts with durations of 1 ms, 10 ms, 100 ms, 1000 ms, 5000 ms and 10000 ms were measured at different intensity levels of 20 dB, 30 dB, 40 dB, 50 dB, 60 dB, 70 dB, 80 dB, 90 dB, 100 dB. The data show that variance of Weber fraction (△I/I) with intensity is distinct from Riesz's result and SPIN theory, and that the relations between Weber fraction and intensity for signals of different durations are similar in spite of Weber fraction decreasing to asymptote with signal duration increasing. This means the difference of pulse measurement of intensity JND from Riesz's result and SPIN theory does not arise from the limited signal duration of pulse method and provides new cue for hearing research. 展开更多
关键词 JND relations of intensity just noticeable difference to intensity of tonal bursts with various durations
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Relationship between outcomes and relative dose intensity of lenvatinib treatment in patients with advanced hepatocellular carcinoma 被引量:1
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作者 Takamasa Ohki Koki Sato +8 位作者 Mayuko Kondo Eriko Goto Takahisa Sato Yuji Kondo Masatoshi Akamatsu Shinpei Sato Hideo Yoshida Yukihiro Koike Shuntaro Obi 《Liver Research》 2020年第4期199-205,共7页
Background and aims:Lenvatinib(LEN)is a newly developed tyrosine kinase inhibitor,and is approved as a first-line treatment for advanced hepatocellular carcinoma(HCC)in Japan.This retrospective multi-center study inve... Background and aims:Lenvatinib(LEN)is a newly developed tyrosine kinase inhibitor,and is approved as a first-line treatment for advanced hepatocellular carcinoma(HCC)in Japan.This retrospective multi-center study investigated the effect of the relative dose intensity(RDI)of LEN on response rate,progression-free survival(PFS),and overall survival(OS).Methods:This retrospective study enrolled 123 patients with advanced HCC who were treated with LEN at six hospitals in Japan between March 2018 and December 2019.These patients were divided into two groups:RDI≥70%(RDI 70 group,N=70)or RDI<70%(control group,N=53)in the first 30 days.The following data were compared between groups:patient backgrounds,adverse events,treatment out-comes,PFS,and OS.PFS and OS were analyzed using the Kaplan-Meier method,followed by the log-rank test.To identify significant factors that contributed to response,PFS,and OS,multivariate analysis was performed using factors for which P-values were<0.10 in univariate analysis.Results:The proportion of patients with Child-Pugh class 5A was significantly greater in the RDI 70 group than that in the control group(64.3%vs.28.3%,P<0.01).Dose interruption due to adverse events was significantly more common in the control group.The response rate was significantly higher in the RDI 70 group than that in the control group(35.7%vs.11.3%,P<0.01).Median PFS was significantly longer in the RDI 70 group(9.4 vs.4.7 months,P<0.01).Multivariate analysis showed that RDI≥70%(hazard ratio(HR)=0.55,P=0.025),hypertension grade≥2(HR=0.47,P=0.019),and response(HR=0.52,P=0.033)were independently associated with improved PFS.Median OS was also significantly longer in the RDI 70 group(20.0 vs.13.3 months,P=0.045).Multivariate analysis showed that female sex(HR=0.33,P=0.034)and disease control(HR=0.31,P<0.01)were independently associated with improved OS.RDI≥70%was not statistically significant in multivariate analysis.Conclusions:Our study revealed the importance of achieving RDI≥70%in the first 30 days of treatment to maximize the effects of LEN。 展开更多
关键词 Advanced hepatocellular carcinoma Lenvatinib(LEN) Relative dose intensity(RDI) CHEMOTHERAPY Tyrosine kinase inhibitor
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Wood Moisture Content Measurement by X-Ray Exposure Method
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作者 尚德库 《Journal of Forestry Research》 SCIE CAS CSCD 1997年第1期54-58,共5页
Although quite a numer of papers can be found up to now dealing with the subject of the measurement ofwood density by using the X-ray exposure methods, direet scanning or radiographic photography, the following two as... Although quite a numer of papers can be found up to now dealing with the subject of the measurement ofwood density by using the X-ray exposure methods, direet scanning or radiographic photography, the following two aspects,which are very important from both theorctical and engineering application points of view, have not yet been properly handled. One is that the elementary analyses or the experimental measurement on the mass attenuation coefficients were notspecified in regard to spectnun energv distridutions [1]. In this connection, the ambiguities in the specification of the coeffiecients and in turn for thc results among studies arise when only one of the two parameters, namely wave length and applied voltage, of detining the energy spectrum of X-ray is given. The oher is that the relationships between the relative intensity and the sample thickness as well the wood moisture content [2], which are the critical factors for the design and theselection of X-ray apparatus, were not sufficiently examined. In addition, the knowledge of the measurelnent of woodmiosture content by using the direct X-ray scanning method is also almost unavaible now. In the study, the direct X-rayscanning method of measuring wood moisture content was at first investigated theoretically with respect to the relationshipbetween the mass attenuation coefficients of wood (beech, Fagus Sylvatica) and the maximum spectrum energy of X-ray.Secondly, the dependence of the relative intensity on the sample thickness and on the wood moisture content was analysed.The main advantage of the method is on-site nondestructive measuring of wood moisture content in the processes such asdrying, impregnation and unsteady mass diffusion. Specifically for the application in the area of biomechanics, the methodcan also bc used for understanding the water pathway within wood, for example, the water around the knots and the relation between the stress distribution and the local moisture content of wood. 展开更多
关键词 Mass attenuation coefficient Maximum spectrum energy Moisture content Relative intensity Sample thickness X-ray exposure
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Chemical Effect Analyses of 3d Elements by Study of X-Ray Fluorescence Spectra
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作者 Sevil(Porikli) DURDAGI 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2018年第8期2630-2637,共8页
Spectra of KX-rays emitted from pure 3 dtransition metals and their oxide and sulfate compounds were measured using a single crystal wavelength dispersive X-ray spectroscopy(WDXRF).The measurements were performed usin... Spectra of KX-rays emitted from pure 3 dtransition metals and their oxide and sulfate compounds were measured using a single crystal wavelength dispersive X-ray spectroscopy(WDXRF).The measurements were performed using a ZSX-100 esequential spectrometer equipped with an RhX-ray tube operated.An accurate analytical representation of each line was obtained by a fit to a Lorentz function.The spectra were analyzed in order to examine the KX-ray peak parameters such as asymmetry index,peak energy and relative intensity ratios.The energy shifts and relative intensities weredetermined tobetter understand the chemical effect. 展开更多
关键词 Asymmetry index Relative intensity ratio Chemical effect Wavelength dispersive X-ray spectroscopy(WDXRF)
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Strong Earthquakes in the Yunnan-Sichuan Region: Evaluation of a Forward Long-to-intermediate-term PI Forecast
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作者 ZHANG Shengfeng ZHANG Yongxian +1 位作者 WU Zhongliang JIANG Changsheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第S01期109-111,共3页
Since the initial international cooperation in the framework of Collaboratory for the Study of Earthquake Predictability(CSEP)in 2007,a lot of forecast models have been developed and served for the earthquake forecast... Since the initial international cooperation in the framework of Collaboratory for the Study of Earthquake Predictability(CSEP)in 2007,a lot of forecast models have been developed and served for the earthquake forecasting experiment in different CSEP testing centers(Schorlemmer et al.,2018). 展开更多
关键词 pattern informatics(PI)algorithm long-to-intermediate-term forecast relative intensity(RI)algorithm relative operating characteristic(ROC)analysis Yunnan-Sichuan region
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Two-Mode Biomedical Sensor Build-up:Characterization of Optical Amplifier
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作者 Usman Masud Fathe Jeribi +3 位作者 Mohammed Alhameed Faraz Akram Ali Tahir Mohammad Yousaf Naudhani 《Computers, Materials & Continua》 SCIE EI 2022年第3期5487-5501,共15页
Intracavity absorption spectroscopy is a strikingly sensitive technique that has been integrated with a two-wavelength setup to develop a sensor for human breath.Various factors are considered in such a scenario,out o... Intracavity absorption spectroscopy is a strikingly sensitive technique that has been integrated with a two-wavelength setup to develop a sensor for human breath.Various factors are considered in such a scenario,out of which Relative Intensity Noise(RIN)has been exploited as an important parameter to characterize and calibrate the said setup.During the performance of an electrical based assessment arrangement which has been developed in the laboratory as an alternative to the expensive Agilent setup,the optical amplifier plays a pivotal role in its development and operation,along with other components and their significance.Therefore,the investigation and technical analysis of the amplifier in the system has been explored in detail.The algorithm developed for the automatic measurements of the system has been effectively deployed in terms of the laser’s performance.With this in perspective,a frequency dependent calibration has been pursued in depth with this scheme which enhances the sensor’s efficiency in terms of its sensitivity.In this way,our investigation helps us in a better understanding and implementation perspective of the proposed system,as the outcomes of our analysis adds to the precision and accuracy of the entire system. 展开更多
关键词 Biomedical sensor cavity optomechanics SPECTROSCOPY relative intensity noise semiconductor laser diode
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Analysis of Rolling Contact Bearings Test Data by the Bımodal Method
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作者 Yaakov Meged 《Advances in Materials Physics and Chemistry》 2021年第1期1-6,共6页
Lieblein J. and Zelen A. conducted a study of the fatigue life of deep groove ball bearings. This study was based on data of 4948 bearings as obtained from 5 companies and 213 test groups. Among these data is a detail... Lieblein J. and Zelen A. conducted a study of the fatigue life of deep groove ball bearings. This study was based on data of 4948 bearings as obtained from 5 companies and 213 test groups. Among these data is a detailed test report #3183, lot 73, consisting of 23 failed bearings. This report states that the Weibull slope of this group is 2.23, meaning that this distribution is mono sloped. These test data were plotted by the author on a bilinear scale plane, of endurance life versus bearing number and proved to be distinctly bi sloped. This basic difference prompted a wide study resulting in several new findings and set the grounds for a new analysis method. 展开更多
关键词 Bimodal Fatigue Mechanism Deep Groove Ball Bearings Mechanical Mode Hydraulic Mode Relative intensity Cavitation Erosion
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Relative intensity noise in high-speed hybrid square-rectangular lasers 被引量:3
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作者 FU-LI WANG XIU-WEN MA +3 位作者 YONG-ZHEN HUANG YUE-DE YANG JUN-YUAN HAN JIN-LONG XIAO 《Photonics Research》 SCIE EI 2018年第3期193-197,共5页
Relative intensity noise(RIN) and high-speed modulation characteristics are investigated for an Al Ga In As/In P hybrid square-rectangular laser(HSRL) with square side length, rectangular length, and width of 15,300, ... Relative intensity noise(RIN) and high-speed modulation characteristics are investigated for an Al Ga In As/In P hybrid square-rectangular laser(HSRL) with square side length, rectangular length, and width of 15,300, and 2 μm, respectively. Single-mode operation with side-mode suppression larger than 40 dB has been realized for the HSRL over wide variation of the injection currents. In addition, the HSRL exhibits a 3 dB modulation bandwidth of 15.5 GHz, and an RIN nearly approaches standard quantum shot-noise limit 2 hv∕P=-164 dB∕Hz at high bias currents due to the strong mode selection of the square microcavity. With the increase of the DC bias current of the Fabry–Perot section, significantly enhanced modulation bandwidth and decreased RIN are observed.Furthermore, intrinsic parameters such as resonance frequency, damping factor, and modified Schawlow–Townes linewidth are extracted from the noise spectra. 展开更多
关键词 RIN Relative intensity noise in high-speed hybrid square-rectangular lasers ISQ
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Cascaded Random Raman Fiber Laser With Low RIN and Wide Wavelength Tunability 被引量:1
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作者 Bing HAN Shisheng DONG +1 位作者 Yang LIU Zinan WANG 《Photonic Sensors》 SCIE EI CSCD 2022年第4期36-44,共9页
Cascaded random Raman fiber lasers(CRRFLs)have been used as a new platform for designing high power and wavelength-agile laser sources.Recently,CRRFL pumped by ytterbium-doped random fiber laser(YRFL)has shown both hi... Cascaded random Raman fiber lasers(CRRFLs)have been used as a new platform for designing high power and wavelength-agile laser sources.Recently,CRRFL pumped by ytterbium-doped random fiber laser(YRFL)has shown both high power output and low relative intensity noise(RIN).Here,by using a wavelength-and bandwidth-tunable point reflector in YRFL,we experimentally investigate the impacts of YRFL on the spectral and RIN properties of the CRRFL.We verify that the bandwidth of the point reflector in YRFL determines the bandwidth and temporal stability of YRFL.It is found that with an increase in the bandwidth of the point reflector in YRFL from 0.2 nm to 1.4 nm,CRRFL with higher spectral purity and lower RIN can be achieved due to better temporal stability of YRFL pump.By broadening the point reflector’s bandwidth to 1.4 nm,the lasing power,spectral purity,and RIN of the 4th-order random lasing at 1349 nm can reach 3.03 W,96.34%,and–115.19 dB/Hz,respectively.For comparison,the spectral purity and RIN of the 4th-order random lasing with the point reflector’s bandwidth of 0.2 nm are only 91.20%and–107.99 dB/Hz,respectively.Also,we realize a wavelength widely tunable CRRFL pumped by a wavelength-tunable YRFL.This work provides a new platform for the development of ideal distributed Raman amplification pump sources based on CRRFLs with both good temporal stability and wide wavelength tunability,which is of great importance in applications of optical fiber communication and distributed sensing. 展开更多
关键词 Random fiber laser Raman fiber laser relative intensity noise distributed Raman amplification
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