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Effect of FeSi additive in dual-chamber sample cup on thermal analysis characteristic values and vermiculating rate of compacted graphite iron
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作者 De-quan Shi Ze-yu Liu +1 位作者 Gui-li Gao Yi-cheng Feng 《China Foundry》 SCIE EI CAS CSCD 2024年第1期91-100,共10页
Thermal analysis plays a key role in the online inspection of molten iron quality.Different solidification process of molten iron can be reflected by thermal analysis curves,and silicon is one of important elements af... Thermal analysis plays a key role in the online inspection of molten iron quality.Different solidification process of molten iron can be reflected by thermal analysis curves,and silicon is one of important elements affecting the solidification of molten iron.In this study,FeSi75 was added in one chamber of the dual-chamber sample cup,and the influences of FeSi75 additive on the characteristic values of thermal analysis curves and vermiculating rate were investigated.The results show that with the increase of FeSi75,the start temperature of austenite formation TALfirstly decreases and then increases,but the start temperature of eutectic growth TSEF,the lowest eutectic temperature TEU,temperature at maximum eutectic reaction rate TEM,and highest eutectic temperature TERkeep always an increase.The temperature at final solidification point TEShas little change.The FeSi75 additive has different influences on the vermiculating rate of molten iron with different vermiculation,and the vermiculating rate increases for lower vermiculation molten iron while decreases for higher one.According to the thermal analysis curves obtained by a dual-chamber sample cup with 0.30wt.%FeSi75 additive in one chamber,the vermiculating rate of molten iron can be evaluated by comparing the characteristic values of these curves.The time differenceΔtERcorresponding to the highest eutectic temperature TERhas a closer relationship with the vermiculating rate,and a parabolic regression curve between the time differenceΔtERand vermiculating rateηhas been obtained within the range of 65%to 95%,which is suitable for the qualified melt. 展开更多
关键词 FeSi75 additive characteristic value vermiculating rate thermal analysis compacted graphite iron
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Image-based Extraction of Characteristic Value of Pathological Leaf Surface 被引量:1
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作者 程鹏飞 周春娥 刘静香 《Plant Diseases and Pests》 CAS 2010年第5期18-20,25,共4页
[ Objective] Computer image processing technology was used to distinguish the angular leaf spot and spotted disease in the agricultural production. [Method] The computer vision technology was used to carry out chromat... [ Objective] Computer image processing technology was used to distinguish the angular leaf spot and spotted disease in the agricultural production. [Method] The computer vision technology was used to carry out chromatic research on the plant pathological characteristics. The color and texture were taken as the plant disease image characteristic parameter to extract the perimeter, area and the shape of the lesion image, thus carrying out the classification judgment on the disease image. [ Result] C IE1976H IS chorma percentage histogram method was adopted to extract chromaticity characteristic parameters, the process was simple and effective with fast operation speed, eliminating the effect of leaf size and shape. The statistical characteristic parameter of chorma histogram was analyzed to obtain chroma skewness, which could significantly distinguish different symptoms of disease. [ Conclusion] The study suggested that chroma skewness could be adopted as the characteristic parameter to distinguish spotted disease with angular leaf spot. 展开更多
关键词 Image processing Contour following Plant disease characteristic value extraction CHROMA
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Effect of Sea Level Variation on Tidal Characteristic Values for the East China Sea 被引量:8
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作者 于宜法 俞聿修 +2 位作者 左军成 万振文 陈宗镛 《海洋工程:英文版》 2003年第3期369-382,共14页
Tidal waves in the East China Sea are simulated numerically with POM(Princeton Ocean Model) model for normal mean sea level, 30 cm higher, 60 cm higher, and 100 cm higher, respectively, and the simulated result is com... Tidal waves in the East China Sea are simulated numerically with POM(Princeton Ocean Model) model for normal mean sea level, 30 cm higher, 60 cm higher, and 100 cm higher, respectively, and the simulated result is compared with the harmonic analysis result of hourly sea level data from 19 tide gauges for more than 19 years. It is indicated that the long-term mean sea level variation affects notably tidal waves in this region. Generally, the tidal amplitude increases when the mean sea level rises, but this relationship may be inverse for some sea areas. The maximal variation of tidal amplitude takes place in the zones near the Fujian coast and the Zhejiang coast, rather than the shallowest Bohai Sea. The maximum increase of M2 amplitude can exceed about 15 cm corresponding to the 60 cm rise of the mean sea level along the Fujian coast. The other regions with large variations of tidal amplitude are those along the Jiangsu coast, the south-east coast of Shandong, and the south-east coast of Dalian. The propagation of tidal waves is also related to mean sea level variation, and the tidal phase-lag decreases generally when the mean sea level rises. Almost all the regions where the tidal phase-lag increases with rising mean sea level are close to amphidromic points, meanwhile the spatial area of such regions is very small. Because the influence of mean sea level variation upon tidal waves is spatially marked, such spatial effect should be considered in calculation of the tidal characteristic value and engineering water level. In the region where the amplitudes of the major tidal constituents increase, the probable maximum high water level becomes higher, the probable maximum low water level becomes lower, and both design water level andcheck water level increase obviously. For example, the design water level at Xiamen increases by 13.5 cm due to the variation of tidal waves when the mean sea level rises 60 cm, the total increase of design water level being 73.5 cm. 展开更多
关键词 East China Sea mean sea level tidal wave variation tidal characteristic value engineering water level
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A MULTICAST KEY MANAGEMENT SCHEME BASED ON CHARACTERISTIC VALUES OF MEMBERS 被引量:1
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作者 Du Xiaoqiang Bao Wansu Fu Xiangqun 《Journal of Electronics(China)》 2012年第3期294-301,共8页
A new collusion attack on Pour-like schemes is proposed in this paper. Then, we present a collusion-free centralized multicast key management scheme based on characteristic values of members. The re-keying method that... A new collusion attack on Pour-like schemes is proposed in this paper. Then, we present a collusion-free centralized multicast key management scheme based on characteristic values of members. The re-keying method that other group members calculate new keys when a member is joining or leaving is also designed. It achieves forward secrecy and backward secrecy. Compared with typical existing centralized schemes, the storage of Group Key Controller (GKC) in our scheme halves the storage overhead of others, and communication overhead of GKC is 2 in case of joining re-keying. Especially, the leaving re-keying overhead is and the overall performance is excellent. 展开更多
关键词 Security multicast Key management characteristic values COLLUSION Re-keying
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A More Effective Method of Extracting the Characteristic Value of Pulse Wave Signal Based on Wavelet Transform 被引量:1
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作者 Xuanwei Zhang Yazhou Shang +3 位作者 Daoxin Guo Tianxia Zhao Qiuping Li Xin’an Wang 《Journal of Biomedical Science and Engineering》 2016年第10期9-19,共11页
Pulse wave contains human physiological and pathological information. Different people will exhibit different characteristics, and hence determining the characteristic points of the pulse wave of human physiological h... Pulse wave contains human physiological and pathological information. Different people will exhibit different characteristics, and hence determining the characteristic points of the pulse wave of human physiological health makes sense. It is common that we extract the characteristic value of pulse wave signal with the method based on wavelet transform on a small scale, and then determine the locations of the characteristic points by modulus maxima and modulus minima. Before determining characteristic value by detecting modulus maxima and modulus minima, we need to determine every period of the pulse wave. This paper presents a new kind of adaptive threshold determination method which is more effective. It can accurately determine every period of the pulse wave, and then extract characteristic values by modulus maxima and modulus minima in every period of the pulse wave. The method presented in this paper promotes the research utilizing pulse wave on health life. 展开更多
关键词 Pulse Wave Wavelet Transform Adaptive Threshold characteristic values
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THE RELATIONSHIP OF QUARTILE CHARACTERISTIC VALUES BETWEEN DENSITY CURVE AND DISTRIBUTION CURVE
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作者 樊民强 刘丽俭 张荣曾 《Journal of Coal Science & Engineering(China)》 1998年第2期85-90,共6页
The characteristics of density yield curve of coal and distribution curve of products can be described with median, quartile deviation, the quartile measure of skewness and kurtosis like K. On the basis of 16 groups o... The characteristics of density yield curve of coal and distribution curve of products can be described with median, quartile deviation, the quartile measure of skewness and kurtosis like K. On the basis of 16 groups of coal density composition data and their jigging stratification data derived from the pilot jig, the regression analysis has been done for the relationship between the characteristic values of the density curve and the characteristic values of the distribution curve.The results show as follow: (1) The bigger the skewness of the density curve, the bigger the probable error (Ep) and imperfection (I ) are. (2) The bigger the median of density curve, the smaller the probable error or imperfection is. (3) The characteristic values of density curve have no influence on the kurtosis K of the distribution curve. 展开更多
关键词 quartile characteristic values density curve distribution curve
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Research on Traditional Village Protection Development Planning Based on Value Characteristics——Taking Heshe Village in Jiangxi Province As An Example 被引量:1
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作者 黄萍 《Agricultural Science & Technology》 CAS 2017年第11期2135-2138,2146,共5页
Traditional villages are the foundation of human history, the crystallization of agricultural civilization, the important carder of homeland feelings, and the spiritual homeland of the Chinese nation. In the important... Traditional villages are the foundation of human history, the crystallization of agricultural civilization, the important carder of homeland feelings, and the spiritual homeland of the Chinese nation. In the important period of attaching importance to the protection of traditional villages and making active plans for the protection and development of traditional villages, the planning of conservation has been stereotyped, which only cares about quantity and speed. Every traditional village has its unique value and soul, and ignoring its internal cultural connotation and value characteristics can result in the lack of scientific and comprehensive planning, making it unable not be implemented in practice. In this paper, taking Heshe Village in Jiangxi Province as an example, the value characteristics oriented planning strategy for traditional villages were proposed through the refinement of its value characteristics based on the scientific planning principles. 展开更多
关键词 value characteristics Conservation planning Heshe Village
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Time-series analysis of the characteristic pressure fluctuations in a conical fluidized bed with negative pressure 被引量:1
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作者 Sheng Fang Yanding Wei +2 位作者 Lei Fu Geng Tian Haibin Qu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第4期87-99,共13页
The negative pressure conical fluidized bed is widely used in the pharmaceutical industry.In this study,experiments based on the negative pressure conical fluidized bed are carried out by changing the material mass an... The negative pressure conical fluidized bed is widely used in the pharmaceutical industry.In this study,experiments based on the negative pressure conical fluidized bed are carried out by changing the material mass and particle size.The pressure fluctuation signals are analyzed by the time and the frequency domain methods.A method for absolutely characterizing the degree of the energy concentration at the main frequency is proposed,where the calculation is to divide the original power spectrum by the average signal power.A phenomenon where the gas velocity curve temporarily stops growing is observed when the material mass is light,and the particle size is small.The standard deviation and kurtosis both rapidly change at the minimum fluidization velocity and thus can be used to determine the flow regime,and the variation rule of the kurtosis is independent of both the material mass and particle size.In the initial fluidization stage,the dominant pressure signal comes from the material movement;with the increase in the gas velocity,the power of a 2.5 Hz signal continues to increase.A method of dividing the main frequency by the average cycle frequency can conveniently determine the fluidized state,and a novel concept called stable fluidized zone proposed in this paper can be obtained.Controlling the gas velocity within the stable fluidized zone ensures that the fluidized bed consistently remains in a stable fluidized state. 展开更多
关键词 Conical fluidized bed Negative pressure Pressure fluctuation Time-series analysis characteristic value Fluidized state
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Research and Application of High-Density Resistivity Method in Seawater Intrusion Investigation in Laizhou Bay
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作者 Yuhai HE Hongjin WANG +3 位作者 Zengcai ZHAO Biao WANG Bin ZHANG Xiaodan WANG 《Agricultural Biotechnology》 2023年第6期88-92,共5页
The disaster of seawater intrusion seriously affects people's lives and restricts economic development,so the detection and treatment of seawater intrusion is a long-term task.On the basis of field investigation a... The disaster of seawater intrusion seriously affects people's lives and restricts economic development,so the detection and treatment of seawater intrusion is a long-term task.On the basis of field investigation and water quality analysis,according to the change characteristics of apparent resistivity of groundwater after Cl-reaches 250 mg/L,the theoretical basis for the application of high-density resistivity method was determined,and the characteristic values of apparent resistivity for seawater intrusion interfaces in different geological characteristic regions in Laizhou Bay area were determined by typical profile tests.Combined with water quality investigation and other means,profiles for the high-density resistivity method were arranged,and the interfaces between saline and fresh water were accurately divided. 展开更多
关键词 High-density resistivity method Seawater intrusion Laizhou Bay characteristic value
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An approach to estimate tidal dissipation with single-point high-frequency ground wave radar data
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作者 毛华斌 陈举 +1 位作者 邱春华 练树民 《Marine Science Bulletin》 2012年第2期46-55,共10页
Using the single-point ground wave (GW) radar data at Shensi Station and the water level data at three stations (Shengsi, Luchaogang and Daishan), the authors obtained the flow vectors from the radial velocity of ... Using the single-point ground wave (GW) radar data at Shensi Station and the water level data at three stations (Shengsi, Luchaogang and Daishan), the authors obtained the flow vectors from the radial velocity of GW radar observation, and calculate four sub-tidal harmonic constants (O1, K1, M2 and S2). The tidal characteristics derived from the GW radar dataset agreed well with those from the tidal gauge data. The authors also analyzed the tidal energy flux and tidal energy dissipation rate. There was a good relationship between the tidal energy dissipation rate and topography. The study showed a good way to calculate tidal energy dissipation rate using GW radar data. 展开更多
关键词 ground wave radar characteristic value tide type tidal energy flux tidaenergy dissipation
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Study on the Distribution Law of Horizontal Seismic Forces between Slab-Column and Shear Wall
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作者 GUO Nan GUO Yihong YANG Yingwei 《沈阳建筑大学学报(自然科学版)》 CAS 北大核心 2012年第3期443-448,共6页
In slab column-shear wall structures,both the whole structure′s seismic behavior and failure mode are greatly influenced by the distribution of horizontal seismic forces between slab-column and shear wall.In this pap... In slab column-shear wall structures,both the whole structure′s seismic behavior and failure mode are greatly influenced by the distribution of horizontal seismic forces between slab-column and shear wall.In this paper,a pushover analysis of topical slab column-shear wall structure was carried out,the seismic shear force that the slab-column and shear wall should undertake was worked out,the influences of plastic internal force redistribution and structure stiffness characteristic value on horizontal seismic distribution were studied and the calculation formula was given.The analysis results showed that with the yield of the shear walls,the story shear force was undertaken by slab-columns correspondingly increased while with the decrease of characteristic value of stiffness of a structure,and the horizontal seismic force was undertaken by slab-columns correspondingly decreased.According to the code,the design of horizontal force distribution may be cause insecurity problems,so it is necessary to give the distribution law of horizontal seismic forces in slab-column shear wall structures as the supplement to the corresponding regulation of the Code. 展开更多
关键词 slab column-shear wall structure horizontal seismic force pushover analysis plastic internal force redistribution characteristic value of stiffness of structure
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The Parallel Calculation of the Ground-State Correlation Energy of Helium Atom
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作者 Liu Lianjun Xu Jingwen +1 位作者 Gu Haitao Liu Yuming 《Wuhan University Journal of Natural Sciences》 CAS 1999年第1期47-50,共4页
When we use Modified Configuration Interaction method(MCI) to calculate the correlation energy of double electron systems, for obtaining the higher precision, we always need huge calculations. In order to handle this... When we use Modified Configuration Interaction method(MCI) to calculate the correlation energy of double electron systems, for obtaining the higher precision, we always need huge calculations. In order to handle this problem, which will cost much CPU time and memory room if only using a single computer to do it, we now adopt the parallel multisection recurrence algorithm. Thus we can use several CPUs to get the ground state energy of a Helium atom at the same time. 展开更多
关键词 Parallel Partitioning Cancellation Iteration Algorithm \ characteristic value equation \ configuration interation (CI) method \ correlation energy
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Extension and Application of the Wielandt-Hoffman Theorem
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作者 DENG Qun 《Journal of China University of Mining and Technology》 EI 2006年第2期233-235,共3页
The Wielandt-Hoffman theorem of the real symmetric matrix is extended into a plural matrix. On the basis of it, a similar theory about the trace of a matrix for the arithmetic mean, geometric mean inequality, Holder i... The Wielandt-Hoffman theorem of the real symmetric matrix is extended into a plural matrix. On the basis of it, a similar theory about the trace of a matrix for the arithmetic mean, geometric mean inequality, Holder inequality and Minkowski inequality is proved. 展开更多
关键词 Hermitian matrix trace of matrix characteristic value INEQUALITY
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NEW APPROACH ON CUTTER PATH GENERATION FOR PLANE MILING
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作者 Ma Weidong, Li Peigen ,Duan Zhengchen Huazhong University, of Science and Technology 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1997年第2期112-118,共3页
A new approach on cutter path generation for plane milling is proposed. The cutter feed status at the position of each grid mesh can be determined by using a specific algorithm consisting of data pro- cessing and some... A new approach on cutter path generation for plane milling is proposed. The cutter feed status at the position of each grid mesh can be determined by using a specific algorithm consisting of data pro- cessing and some heuristic rules. From the cutter feed status and the coordinates of the grid meshes, the cutter path for milling plane can be generated. 展开更多
关键词 Cutter path Grid mesh characteristic value Feed status
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A Method to Prove Convergence of Some Nonlinear Differential Equation's Form Solution
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作者 刘钧 朱其敬 吴浩生 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第4期16-19, ,共4页
A method to prove the convergence of some nonlinear differential equation’s from solu tion and its existance.
关键词 characteristice value strong function analystic solution
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Defect Recognition in Thermosonic Imaging 被引量:4
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作者 CHEN Dapeng WU Naiming ZHANG Zheng 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2012年第4期657-662,共6页
This work is aimed at developing an effective method for defect recognition in thermosonic imaging.The heat mechanism of thermosonic imaging is introduced,and the problem for defect recognition is discussed.For this p... This work is aimed at developing an effective method for defect recognition in thermosonic imaging.The heat mechanism of thermosonic imaging is introduced,and the problem for defect recognition is discussed.For this purpose,defect existing in the inner wall of a metal pipeline specimen and defects embedded in a carbon fiber reinforced plastic(CFRP) laminate are tested.The experimental data are processed by pulse phase thermography(PPT) method to show the phase images at different frequencies,and the characteristic of phase angle vs frequency curve of thermal anomalies and sound area is analyzed.A binary image,which is based on the characteristic value of defects,is obtained by a new recognition algorithm to show the defects.Results demonstrate good defect recognition performance for thermosonic imaging,and the reliability of this technique can be improved by the method. 展开更多
关键词 thermosonic imaging defect recognition Fourier transforms characteristic value carbon fiber reinforced plastic
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A Dynamic Input- Output Model Solution
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作者 GENG Xian\|min Xinjiang Petroleum Institute, Urumqi 830000, China 《Systems Science and Systems Engineering》 CSCD 1999年第3期290-298,共9页
In this paper we research the homogeneous input output model of forward delay that lag is one production cycle. It is conformed that the necessary and sufficient conditions of economic balanced development are that t... In this paper we research the homogeneous input output model of forward delay that lag is one production cycle. It is conformed that the necessary and sufficient conditions of economic balanced development are that the output vector GENG Xian\|min Xinjiang Petroleum Institute, Urumqi 830000, ChinaAbstract:\ In this paper we research the homogeneous input output model of forward delay that lag is one production cycle. It is conformed that the necessary and sufficient conditions of economic balanced development are that the output vector X(t) is the right positive characteristic vector of (I-A) -1 (A+B), and the input vector is AX(t). We also constitute the workable economic subset S-,when the output vector of the first production cycle is X(1), the economy will surely collapse. 展开更多
关键词 input output consumption coefficient matrix investment coefficient matrix irreducible nonnegative matrix maximum characteristic value
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