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China’s Perspectives on the Modern Educational Value of Critical Information Literacy
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作者 Min Liao 《Journal of Contemporary Educational Research》 2024年第7期174-181,共8页
Critical information literacy is a new and important direction of information literacy education for university students in the new media era.By comparing critical information literacy between China and the West,combi... Critical information literacy is a new and important direction of information literacy education for university students in the new media era.By comparing critical information literacy between China and the West,combining with the research on information literacy education in China in the past 20 years,and based on the three major relationships that Chinese philosophy is concerned about that people need to face in the world of life,i.e.,the individual and the self,the individual and nature,and the individual and the society,this paper defines critical information literacy as that individuals,as information subjects,discover,select,confirm,and evaluate the information they are exposed to by obtaining and discriminating the content elements of the information world(information sources,information,and information assets)and using critical thinking skills and methods,creatively interpret or solve the relevant problems arising from the interaction between individuals and self,individuals and nature,individuals and society,and form the literacy that represents the knowledge,ability,attitude,habit,and level of the information subject through continuous reflection and practice.In order for human beings to better understand the world and construct it responsibly,critical information literacy can play a greater role and educational value.It not only helps contemporary college students build knowledge of“good questioning”and enhance their“reasoning”skills,but also encourages them to maintain a“firm standpoint,”cultivate a habit of“healthy skepticism,”and enhance their“decision-making”skills. 展开更多
关键词 New media University students critical information literacy Educational value Chinese philosophy
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Examination of Silicate Limitation of Primary Production in Jiaozhou Bay, China Ⅱ. Critical Value and Time of Silicate Limitation and Satisfaction of the Phytoplankton Growth 被引量:32
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作者 杨东方 张经 +2 位作者 高振会 陈豫 孙培艳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2003年第1期46-63,共18页
Analysis and comparison of Jiaozhou Bay data collected from May 1991 to February 1994 revealed the spatiotemporal variations of the ambient Si(OH) 4∶NO 3 (Si∶N) concentration ratios and the seasonal variations of (S... Analysis and comparison of Jiaozhou Bay data collected from May 1991 to February 1994 revealed the spatiotemporal variations of the ambient Si(OH) 4∶NO 3 (Si∶N) concentration ratios and the seasonal variations of (Si∶N) ratios in Jiaozhou Bay and showed that the Si∶N ratios were < 1 throughout Jiaozhou Bay in spring, autumn, and winter. These results provide further evidence that silicate limits the growth of phytoplankton (i.e. diatoms) in spring, autumn and winter. Moreover, comparison of the spatiotemporal variations of the Si∶N ratio and primary production in Jiaozhou Bay suggested their close relationship. The spatiotemporal pattern of dissolved silicate matched well that of primary production in Jiaozhou Bay. Along with the environmental change of Jiaozhou Bay in the last thirty years, the N and P concentrations tended to rise, whereas Si concentration showed cyclic seasonal variations. With the variation of nutrient Si limiting the primary production in mind, the authors found that the range of values of primary production is divided into three parts: the basic value of Si limited primary production, the extent of Si limited primary production and the critical value of Si limited primary production, which can be calculated for Jiaozhou Bay by Equations (1), (2) and (3), showing that the time of the critical value of Si limitation of phytoplankton growth in Jiaozhou Bay is around November 3 to November 13 in autumn; and that the time of the critical value of Si satisfaction of phytoplankton growth in Jiaozhou Bay is around May 22 to June 7 in spring. Moreover, the calculated critical value of Si satisfactory for phytoplankton growth is 2.15-0.76 μmol/L and the critical value of Si limitation of phytoplankton growth is 1.42-0.36 μmol/L; so that the time period of Si limitation of phytoplankton growth is around November 13 to May 22 in the next year; the time period of Si satisfactory for phytoplankton growth is around June 7 to November 3. This result also explains why critical values of nutrient silicon affect phytoplankton growth in spring and autumn are different in different waters of Jiaozhou Bay and also indicates how the silicate concentration affects the phytoplankton assemblage structure. The dilution of silicate concentration by seawater exchange affects the growth of phytoplankton so that the primary production of phytoplankton declines outside Jiaozhou Bay earlier than inside Jiaozhou Bay by one and half months. This study showed that Jiaozhou Bay phytoplankton badly need silicon and respond very sensitively and rapidly to the variation of silicon. 展开更多
关键词 PHYTOPLANKTON limitation and satisfaction critical value Jiaozhou Bay
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Minimum critical thickness of dike for ore-bearing fluid injection:A new approach applied to the Shihu gold deposit,Hebei Province,North China 被引量:6
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作者 Dedong Li Yuwang Wang +4 位作者 Jingbin Wang Zhaohua Luo Jiulong Zhou Zongfeng Yang Cui Liu 《Geoscience Frontiers》 SCIE CAS 2012年第5期717-728,共12页
According to the metallogenic theory by transmagmatic fluid (TMF), one magmatic intrusion is a channel of ore-bearing fluids, but not their source. Therefore, it is possible to use TMF's ability for injection into ... According to the metallogenic theory by transmagmatic fluid (TMF), one magmatic intrusion is a channel of ore-bearing fluids, but not their source. Therefore, it is possible to use TMF's ability for injection into and for escaping t^om the magmatic intrusion to evaluate its ore-forming potential. As the ore-bearing fluids cannot effectively inject into the magmatic intrusion when the magma fully crystal- lized, the cooling time and rates viscosity varied can be used to estimate the minimum critical thickness of the intrusion. One dimensional heat transfer model is used to determine the cooling time for three representative dikes of different composition (granite porphyry, quartz diorite and diabase) in the Shihu gold deposit. It also estimated the rates viscosity varied in these time interval. We took the thickness of dike at the intersection of the cooling time -- thickness curve and the rates viscosity varied versus thick- ness curve as the minimum critical thickness. For the ore-bearing fluids effectively injecting into the magma, the minimum critical thicknesses for the three representative dikes are 33.45 m for granite porphyry, 8.22 m for quartz diorite and 1.02 m for diabase, indicating that ore-bearing dikes must be thicker than each value. These results are consistent with the occurrence of ore bodies, and thus they could be applied in practice. Based on the statistical relationship between the length and the width of dikes, these critical thicknesses are used to compute critical areas: 0.0003--0.0016 km2 for diabase, 0.014--0.068 km2 for quartz diorite and 0.011-0.034 km2 for granite porphyry. This implies that ore- bearing minor intrusions have varied areas corresponding to their composition. The numerical simulation has provided the theoretical threshold of exposed thickness and area of the ore-bearing intrusion. These values can be used to determine the ore-forming potentials of dikes. 展开更多
关键词 Dike swarm Cooling time Numerical simulationMinor intrusion critical thickness Transmagmatic fluid
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A circular zone counting method of identifying a Duffing oscillator state transition and determining the critical value in weak signal detection 被引量:3
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作者 李梦平 许雪梅 +1 位作者 杨兵初 丁家峰 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第6期192-197,共6页
Identifying state transition and determining the critical value of the Duffing oscillator are crucial to indicating external signal existence and have a great influence on detection accuracy in weak signal detection. ... Identifying state transition and determining the critical value of the Duffing oscillator are crucial to indicating external signal existence and have a great influence on detection accuracy in weak signal detection. A circular zone counting (CZC) method is proposed in this paper, by combining the Duffing oscillator's phase trajectory feature and numerical calculation for quickly and accurately identifying state transition and determining the critical value, to realize a high- efficiency weak signal detection. Detailed model analysis and method construction of the CZC method are introduced. Numerical experiments into the reliability of the proposed CZC method compared with the maximum Lyapunov exponent (MLE) method are carried out. The CZC method is demonstrated to have better detecting ability than the MLE method, and furthermore it is simpler and clearer in calculation to extend to engineering application. 展开更多
关键词 identifying state transition determining critical value Duffing oscillator circular zone countingmethod maximum Lyapunov exponent method
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Determination of indices and critical values of gas parameters of the first gas outburst in a coal seam of the Xieqiao Mine 被引量:4
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作者 Ou Jianchun Liu Mingju +2 位作者 Zhang Chunru Liu Yanwei Wei Jianping 《International Journal of Mining Science and Technology》 2012年第1期89-93,共5页
Based on the important role in mine safety played by parameters of the first gas outburst, we propose a method of combining historic data, theoretical analysis and experimental research for the purpose of crit- ical v... Based on the important role in mine safety played by parameters of the first gas outburst, we propose a method of combining historic data, theoretical analysis and experimental research for the purpose of crit- ical values of gas parameters of the first gas outburst in a coal seam of the Xieqiao Mine. According to a characteristic analysis and a summary of the rules of coal and gas outbursts in the No.8 coal seam of a Hua- inan mine, we have investigated their effect on coal and gas outbursts in terms such as ground stress, gas, and coal structure. We have selected gas parameters and determined the critical values of each of the fol- lowing indices: gas content as 7.7 m^3/t, tectonic coal as 0.8 m thick, the absolute gas emission as 2 m3/min, the rate of change as 0.7 m3/min, the gas desorption index of a drilling chip KI as 0.26 mL/(g min^1/2) and the values of desorption indexes Ah2 as 200 Pa. From a verification of the production, the results indicate that application of each index and their critical values significantly improve the level of safety in the pro- duction process, relieve the burden upon the mine, save much labor and bring clear economic benefits. 展开更多
关键词 Parameters of first gas outburst Gas content thickness of tectonic coal critical value Coal and gas outbursts
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Determination of the Critical Value of Deflection for Embedded Cylindrical Structures
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作者 刘建起 陈滨 王海艳 《China Ocean Engineering》 SCIE EI 2005年第3期519-528,共10页
An embedded cylinder is a large-diameter cylinder embedded in a soil foundation. The state of failure of such an embedded cylindrical structure shows large deflection instead of slide and overturn of the traditional g... An embedded cylinder is a large-diameter cylinder embedded in a soil foundation. The state of failure of such an embedded cylindrical structure shows large deflection instead of slide and overturn of the traditional gravity type of structure placed on a rubble base or foundation base. The critical value of deflection of the embedded cylindrical structure, which is the maximum allowable deflection for stability calculation of the cylinder, is a vital control value. Through investigation on deflection and soil pressures on an embedded cylinder by model experiments, the variations of the angle of rotation θ of a cylinder with effective anti-overturning ratio η and moment MH of thrust are discussed. On the basis of experimental study, the critical value of deflection of the cylindrical structure is proposed in the paper. Meanwhile, the formulas for calculating deflection of cylinders are derived. 展开更多
关键词 deflection of cylinder critical value of deflection effective anti-overturning ratio moment of thrust calculation of deflection
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Integral Operator Solving Process of the Boundary Value Problem of Abstract Kinetic Equation with the First Kind of Critical Parameter and Generalized Periodic Boundary Conditions
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作者 YU De-jian 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期110-117,共8页
In this paper the concepts of the boundary value problem of abstract kinetic equation with the first kind of critical parameter γ 0 and generalized periodic boundary conditions are introduced in a Lebesgue space whic... In this paper the concepts of the boundary value problem of abstract kinetic equation with the first kind of critical parameter γ 0 and generalized periodic boundary conditions are introduced in a Lebesgue space which consists of functions with vector valued in a general Banach space, and then describe the solution of these abstract boundary value problem by the abstract linear integral operator of Volterra type. We call this process the integral operator solving process. 展开更多
关键词 abstract kinetic equation with the first kind of critical parameter boundary value problem of abstract kinetic equation generalized periodic boundary conditions abstract linear integral operator of Volterra type integral operator solving process
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Critical Discourse Analysis on the Orientation and Value of Modality in English Political Interviews
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作者 Zhang Ni 《西安翻译学院学报》 2019年第3期51-57,共7页
The paper conducts Critical Discourse Analysis on the use of Modality in political interviews. The purpose of this study is to investigate whether the use of Motlality is driven by the speakers' ideology, and thus... The paper conducts Critical Discourse Analysis on the use of Modality in political interviews. The purpose of this study is to investigate whether the use of Motlality is driven by the speakers' ideology, and thus helps lo build the power relationships between the two participants. Such a linguistic awareness can inform a capacity to resist and change exploitative and dominating linguistic practices, and it' s an issue of importance to everyone with a concem and interest in the problems of our contemporary society. With such awareness, people can get a more incisive recogni-tion and judgment of the political implications, and correctly acquire new trends in politics and developnient of current affairs. 展开更多
关键词 critical discourse analysis ORIENTATION and value of MODALITY ENGLISH POLITICAL interviews
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SOLUTIONS TO DISCRETE MULTIPARAMETER PERIODIC BOUNDARY VALUE PROBLEMS INVOLVING THE p-LAPLACIAN VIA CRITICAL POINT THEORY 被引量:8
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作者 高承华 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1225-1236,共12页
In this paper, we consider the existence of three nontrivial solutions for a discrete non-linear multiparameter periodic problem involving the p-Laplacian. By using the similar method for the Dirichlet boundary value ... In this paper, we consider the existence of three nontrivial solutions for a discrete non-linear multiparameter periodic problem involving the p-Laplacian. By using the similar method for the Dirichlet boundary value problems in [C. Bonanno and P. Candito, Appl. Anal., 88(4) (2009), pp. 605-616], we construct two new strong maximum principles and obtain that the boundary value problem has three positive solutions for λ and μ in some suitable intervals. The approaches we use are the critical point theory. 展开更多
关键词 discrete periodic boundary value problem P-LAPLACIAN MULTIPARAMETER three solutions critical point theory
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Assessment of quadriceps muscle thickness using bedside ultrasonography by nurses and physicians in the intensive care unit:Intra- and inter-operator agreement 被引量:2
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作者 Rohit Kumar Tajamul Hussain Shah +5 位作者 Vijay Hadda Pawan Tiwari Saurabh Mittal Karan Madan Maroof Ahmad Khan Anant Mohan 《World Journal of Critical Care Medicine》 2019年第7期127-134,共8页
BACKGROUND Data regarding the agreement among multiple operators for measurement of quadriceps muscle thickness by bedside ultrasonography(USG)are sparse.AIM To statistically assess the agreement among 5 operators for... BACKGROUND Data regarding the agreement among multiple operators for measurement of quadriceps muscle thickness by bedside ultrasonography(USG)are sparse.AIM To statistically assess the agreement among 5 operators for measurement of quadriceps muscle thickness on bedside USG.METHODS This was a cross-sectional observational study.The 5 operators of varied experience(comprised of 1 critical care consultant,2 fellows,and 2 nurses)independently measured quadriceps muscle thickness in triplicate for 45 critically ill patients each,using USG.Intra-and interrater agreement rates among the 5 operators were assessed using intraclass correlation coefficient(ICC)and expressed with 95%confidence interval(CI).RESULTS The 5 operators produced a total of 135 readings and 675 observations for ICC calculations to determine the intraoperator and interoperator variations respectively.For intraoperator agreement,the overall ICC(95%CI)was 0.998(0.997,0.999)for operator 1,0.998(0.997,0.999)for operator 2,0.997(0.995,0.999)for operator 3,0.999(0.998,0.999)for operator 4,and 0.998(0.997,0.999)for operator 5.For interoperator agreement,the overall ICC(95%CI)was 0.977(0.965,0.986;P<0.001)for reading 1,0.974(0.960,0.984;P<0.001)for reading 2,and 0.975(0.961,0.985;P<0.001)for reading 3.CONCLUSION USG measurement of quadriceps muscle thickness was not dependent on clinical experience,supporting training for nurses in it. 展开更多
关键词 AGREEMENT INTENSIVE care unit critical illness Muscle thickness Quadricepsmuscle ULTRASONOGRAPHY
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System Identification Method for Evaluating the Effect of Thickness Error on Backcalculated Pavement Layer Moduli 被引量:1
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作者 ZHONG Yan-hui WANG Fu-ming ZHANG Bei CAI Ying-chun 《上海交通大学学报》 EI CAS CSCD 北大核心 2004年第z2期182-187,共6页
Based on system identification theory and FWD testing data, the effect of thickness error on backcalculating pavement layer moduli is studied and the method of singular value decomposition (SVD) is presented to solve ... Based on system identification theory and FWD testing data, the effect of thickness error on backcalculating pavement layer moduli is studied and the method of singular value decomposition (SVD) is presented to solve the morbidity problem of sensitivity matrix in this paper.The results show that the thickness error has great effects on the backcalculated pavement layer moduli. The error of backcalculated moduli can be controlled within the range of ±15% by limiting the thickness error within the range of ±5%. 展开更多
关键词 system identification SINGULAR value decomposition (SVD) backcalculation PAVEMENT FALLING weight DEFLECTOMETER (FWD) MODULI thickness
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Economic Critical Resources for the Industrial Exploitation of Natural Gas Hydrate 被引量:1
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作者 CHEN Xuejun LU Hailong +2 位作者 ZHANG Jiecheng YE Jianliang XIE Wenwei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第2期663-673,共11页
Since the implementation of several pilot production tests were in natural gas hydrate(NGH) reservoirs in terrestrial and marine settings, the study of NGH has entered a new stage of technological development for indu... Since the implementation of several pilot production tests were in natural gas hydrate(NGH) reservoirs in terrestrial and marine settings, the study of NGH has entered a new stage of technological development for industrial exploitation. Prior to the industrial exploitation of any given NGH reservoir, the economic feasibility should be examined. The first step of economic evaluation of a NGH reservoir is to know whether its resource amount meets the requirement for industrial exploitation. Unfortunately, few relevant studies have been conducted in this regard. In this study, the net present value(NPV) method is employed to estimate the economic critical resources required for the industrial exploitation of NGHs under different production scenarios. Sensitivity analysis is also performed in order to specify the effects of key factors, such as the number of production wells, gas price, technological improvement and tax incentive, on the economic critical resources. The results indicate that China requires the lowest economic critical resource for a NGH reservoir to be industrially exploited, ranging from 3.62 to 24.02 billion m3 methane. Changes in gas price and tax incentives also play significant roles in affecting the threshold and timeline for the industrial exploitation of NGH. 展开更多
关键词 natural gas hydrate industrial exploitation economic critical resource net present value recovery factor
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A critical analysis of environmental evolutionin the loess-plateau area
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作者 Lu Zhongchen(Research Center for Eco - Environmental Sciences. Chinese Academy of Sciences , Beijing 100085, China)Yuan Baoyin(Institute of Geology, Chinese Academy of Bciences . Beijing 100029 . China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1995年第3期283-288,共6页
Acriticalanalysisofenvironmentalevolutionintheloess-plateauareaLuZhongchen(ResearchCenterforEco-Environmenta... Acriticalanalysisofenvironmentalevolutionintheloess-plateauareaLuZhongchen(ResearchCenterforEco-EnvironmentalSciences.Chinese... 展开更多
关键词 critical analysis geomorphologic developing stage: erosion integrated value.
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Long-term phosphorus accumulation and agronomic and environmtal critical phosphorus levels in Haplic Luvisol soil, northern China 被引量:14
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作者 XI Bin ZHAI Li-mei +5 位作者 LIU Jian LIU Shen WANG Hong-yuan LUO Chun-yan REN Tian-zhi LIU Hong-bin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第1期200-208,共9页
Sufficient soil phosphorus (P) content is essential for achieving optimal crop yields, but accumulation of P in the soil due to excessive P applications can cause a risk of P loss and contribute to eutrophication of... Sufficient soil phosphorus (P) content is essential for achieving optimal crop yields, but accumulation of P in the soil due to excessive P applications can cause a risk of P loss and contribute to eutrophication of surface waters. Determination of a critical soil P value is fundamental for making appropriate P fertilization recommendations to ensure safety of both environment and crop production. In this study, agronomic and environmental critical P levels were determined by using linear-linear and linear-plateau models, and two segment linear model, for a maize (Zea mays L.)-winter wheat (Triticum aestivum L.) rotation system based on a 22-yr field experiment on a Haplic Luvisol soil in northern China. This study included six treatments: control (unfertilized), no P (NoP), application of mineral P fertilizer (MinP), MinP plus return of maize straw (MinP+StrP), MinP plus low rate of farmyard swine manure (MinP+L.Man) and MinP plus high rate of manure (MinP+ H.Man). Based on the two models, the mean agronomic critical levels of soil Olsen-P for optimal maize and wheat yields were 12.3 and 12.8 mg kg-1, respectively. The environmental critical P value as an indicator for P leaching was 30.6 mg Olsen-P kg-1, which was 2.4 times higher than the agronomic critical P value (on average 12.5 mg P kg-1). It was calculated that soil OIsen-P content would reach the environmental critical P value in 41 years in the MinP treatment, but in only 5-6 years in the two manure treatments. Application of manure could significantly raise soil Olsen-P content and cause an obvious risk of P leaching. In conclusion, the threshold range of soil Olsen-P is from 12.5 to 30.6 mg P kg-1 to optimize crop yields and meanwhile maintain relatively low risk of P leaching in Haplic Luvisol soil, northern China. 展开更多
关键词 critical phosphorus value crop yield Olsen P phosphorus leaching soil phosphorus test water quality
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Fractal analysis on the spatial distribution of acoustic emission in the failure process of rock specimens 被引量:4
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作者 Rui-fu Yuan Yuan-hui Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2009年第1期19-24,共6页
The spatial distribution of acoustic emission (AE) events in the failure process of several rock specimens was acquired using an advanced AE acquiring and analyzing system. The box counting method (BCM) was employ... The spatial distribution of acoustic emission (AE) events in the failure process of several rock specimens was acquired using an advanced AE acquiring and analyzing system. The box counting method (BCM) was employed to calculate the fractal dimension (FD) of AE spatial distribution. There is a similar correlation between the fractal dimension and the load strength for different rock specimens. The fractal dimension presents a decreasing trend with the increase of load strength. For the same kind of specimens, their FD values will decrease to the level below a relatively same value when they reach failure. This value can be regarded as the critical value, which implies that the specimen will reach failure soon. The results reflect that it is possible to correlate the damage of rock with a macroscopic parameter, the FD value of AE signals. Furthermore, the FD value can be also used to forecast the final failure of rock. This conclusion allows identifying or predicting the damage in rock with a great advantage over the classic theory and is very crucial for forecasting rockburst or other dynamic disasters in mines. 展开更多
关键词 ROCKBURST acoustic emission spatial distribution fractal dimension critical value DAMAGE
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The Innovation Research of Financial Early-Warning Index Measurement 被引量:3
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作者 Zhang You-tang Cheng Jun-ning Liang Wei-jun 《Wuhan University Journal of Natural Sciences》 CAS 2002年第3期281-284,共4页
The period economic fluctuation is vital for an enterprise to exist and further develop, it directly affect the enterprise financial health. So, it is significant to build up financial early-warning index and measure ... The period economic fluctuation is vital for an enterprise to exist and further develop, it directly affect the enterprise financial health. So, it is significant to build up financial early-warning index and measure the warning condition that the enterprise faces and take the effective measures to eliminate. We criticize Altman’sZ calculating model and build up some new indexes for enterprise financial early-warning condition measuring and making sound decision. 展开更多
关键词 financial early-warning index critical value cash earning value cash added value
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Effects of temperature and strain rate on critical damage value of AZ80 magnesium alloy 被引量:4
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作者 夏玉峰 权国政 周杰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第B07期580-583,共4页
A series of AZ80 billets were compressed with 60%height reduction on hot process simulator at 250,300,350,400℃ under strain rates of 0.01,0.1,1 and 10 s- 1.In order to predict the occurrence of surface fracture,the v... A series of AZ80 billets were compressed with 60%height reduction on hot process simulator at 250,300,350,400℃ under strain rates of 0.01,0.1,1 and 10 s- 1.In order to predict the occurrence of surface fracture,the values of the Cockcroft-Latham equation were calculated by the corresponding finite element numerical algorithm developed.A concept about damage incremental ratio in plastic deformation was defined as the ratio of damage increment at one step to the accumulated value.A method of finding the intersection of incremental ratio varying curve and simulation step axis was brought forward to make the fracture step certain. Then,the effects of temperature and strain rate on critical damage value were achieved.The results show that the critical damage value is not a constant but changes in a range of 0.021 8-0.378 0.It decreases significantly with the increase of strain rate at a certain temperature.While under a certain strain rate,the critical damage value has little change with the increase of temperature. 展开更多
关键词 AZ80 magnesium alloy critical damage value COMPACTION finite element analysis
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THE INFLUENCE OF THE DIFFERENT DISTRIBUTEDPHASE-RANDOMIZED ON THE EXPERIMENTAL DATA OBTAINEd IN DYNAMIC ANALYSIS 被引量:1
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作者 马军海 陈予恕 刘曾荣 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第11期0-0,0-0+0-0+0-0+0-0,共10页
In this paper the influence of the differently distributed phase-randontized to the data obtained in dynamic analysis for critical value is studied.The calculation results validate that the sufficient phase-randomized... In this paper the influence of the differently distributed phase-randontized to the data obtained in dynamic analysis for critical value is studied.The calculation results validate that the sufficient phase-randomized of the different distributed random numbers are less influential on the critical value . This offers the theoretical foundation of the feasibility and practicality of the phase-randomized method. 展开更多
关键词 experimental data surrogate data critical value phaserandomized random timeseries chaotic timeseries
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Critical Value of CO of Forecasting Coal Spontaneous Combustion 被引量:7
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作者 何启林 戴广龙 王德明 《Journal of China University of Mining and Technology》 2003年第2期121-125,共5页
CO has been used widely in the production process of colliery as an index gas to predict spontaneous combustion of coal. But in some collieries there are CO gas in the upper corner of the face all the times, sometime ... CO has been used widely in the production process of colliery as an index gas to predict spontaneous combustion of coal. But in some collieries there are CO gas in the upper corner of the face all the times, sometime CO gas even exceeds the regulated critical index. This phenomenon is much more obvious in the fully-mechanized longwall face and fully-mechanized longwall and top-coal caving face. Although many measures of fire-proof and fire-extinguishing have been adopted, the flowing amount of CO gas can be only decreasd, but can not be eliminated completely. Using the different kinds of coal, the experiment of coal oxidation was made at the low temperature. The experiment indicates that some kinds of coal can produce CO under the condition of normal temperature oxidation, sometime the CO consistency is very high, and the intension of CO can be decreased with oxidation time prolonging. Selecting rational critical value of CO is the kev to predicting spontaneous combustion of coal correctly and reliably. The problem of selecting retional critical value of CO was studied. Finally, the amount of CO gas released by different kinds of coal was obtained under normal temperature condition. 展开更多
关键词 coal spontaneous combustion index gas t critical value
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Assessment of Cation Exchange Membrane Method and Estimation of Potassium Critical Values 被引量:1
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作者 SHENJIANBO J.J.SCHOENAU 《Pedosphere》 SCIE CAS CSCD 1996年第2期129-138,共10页
Soil and tissue analyses are usually used in identifying potassium(K) deficiencies and predicting K fertilizer requirements of crops.The critical levels of both soil and fresh leaf tissue at seventh leaf stage were de... Soil and tissue analyses are usually used in identifying potassium(K) deficiencies and predicting K fertilizer requirements of crops.The critical levels of both soil and fresh leaf tissue at seventh leaf stage were developed and assessed for canola,chickpea and sunflower grown on two Saskatchewan,soils,with six rates of K fertilizer supply, in a growth chamber experiment.The available potassium in soils was determined by two methods:1)resin strip extraction, and 2) NH4OAC extraction. The potassium in fresh leaves was determined at seventh leaf stage by a simple procedure using a common garlic press and injector to extract the plant sap and testing the sap with a handheld ion selection electrode meter. The results shoWed significant relationships between the resin strip extractable K and NH4OAC extractable K, and between the plant uptake of total K and the supply of available K in the soils determined by the two methods. Good relationships were also found between the potassium in fresh leaves and the plant uptake of total K for canola, chickpea and sunflower.The resin strip extraction for K was calibrated using common NH4OAC extraction, and recommended for routine analyses because of its simplicity and sensitivity. 展开更多
关键词 CANOLA cation exchange membrane CHICKPEA potassium critical values SUNFLOWER
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