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Correlation between corneal demarcation line depth in epithelium-off and trans-epithelium accelerated corneal cross linking and keratoconus progression 被引量:2
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作者 Mahmoud Abdel-Radi Zeiad Eldaly +3 位作者 Hazem Abdelmotaal Reham Abdelrahman Mohamed Sayed Kamel Soliman 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第6期907-912,共6页
AIM:To compare corneal demarcation line(DL)depth in both accelerated epithelium-off and trans-epithelium cross linking(CXL)using anterior segment optical coherence tomography(AS-OCT)and its relation to maximum keratom... AIM:To compare corneal demarcation line(DL)depth in both accelerated epithelium-off and trans-epithelium cross linking(CXL)using anterior segment optical coherence tomography(AS-OCT)and its relation to maximum keratometry(Kmax)progression in both techniques.METHODS:A prospective comparative interventional study where patients with mild to moderate keratoconus(KC)were classified into two groups:accelerated epitheliumoff and trans-epithelium CXL based on corneal pachymetry.Assessment of corneal DL depth was carried out after 3mo by AS-OCT.Kmax readings were evaluated after one year follow up using the Scheimpflug imaging system.RESULTS:Study included 74 eyes of 44 patients.Group A underwent epithelium-off CXL(41 eyes),while Group B underwent trans-epithelium CXL(33 eyes).At 3mo follow up,mean corneal DL depth in Group A was 219.9±58.4μm while in Group B was 127.2±7.8μm(P<0.05).The mean Kmaxchangedfrom51.9±3.9to51.3±4.2dioptersin Group A and from 53.1±4.1 to 53.6±5 diopters in Group B with insignificant difference in Kmax changes in either group(P>0.05).In addition,no significant change in corneal pachymetry was found in both groups(meanchange at 1y:6.4±4.7 and-10.1±2.3μm in Groups A and B respectively).CONCLUSION:Despite a significantly deeper corneal DL depth created by accelerated epithelium-off CXL technique compared to accelerated trans-epithelium CXL,there is no significant impact on keratoconus progression. 展开更多
关键词 anterior segment optical coherence tomography cross linking demarcation line KERATOCONUS
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Demarcation of Seabuckthorn Plantations in Three Northern Areas of China 被引量:1
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作者 Hu Jian-zhong 《Forestry Studies in China》 CAS 2005年第4期41-48,共8页
Seabuckthorn (Hippophae rhamnoides) planting areas in the three northern areas (north, northeast and northwest) of China are divided into five planting zones: the semi-humid forest prairie climate zone for ecolog... Seabuckthorn (Hippophae rhamnoides) planting areas in the three northern areas (north, northeast and northwest) of China are divided into five planting zones: the semi-humid forest prairie climate zone for ecological and economic types of seabuckthorn plantations in the southern part of the Loess Plateau; the semi-arid steppe climate zone for similar types of plantations in the central part of the Loess Plateau; the arid desert steppe climate zone for ecological type of seabuckthorn plantations in the northern part of the Loess Plateau; the semi-arid and semi-humid steppe climate zone again for ecological and economic types of plantations in northern Hebei and western Liaoning and the cold humid steppe climate zone for economic types of plantations in the northern part of northeast China. The aim of this demarcation is to avoid a random introduction of seabuckthorn. In each of the five zones, objectives should be set and suitable seabuckthorn species, subspecies and varieties should be planted according to site conditions, seed sources and methods of tree breeding. The cultivation centers, bases, stations, or units should be established and successful models of seedling and planting methods should be encouraged. The principle of matching trees with suitable site conditions and adjusting measures to local conditions should be practiced. From a strategic viewpoint of solving ecological and economic problems of seabuckthorn development in the three northern areas, every seabuckthorn center must have its own germplasm nursery, standard plantation for popularizing, excellent seed and seedling nurseries and sufficient afforestation areas for demonstration and propaganda purposes. These measures would improve the ecological environment and promote economic and social development in the three northern areas of China. 展开更多
关键词 demarcation PLANTATION planting model SEABUCKTHORN three northern areas
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Poor rich demarcation of Matthew effect on scale-free systems and its application
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作者 闫栋 董明 +1 位作者 Abdelaziz Bourasc 于随然 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期27-32,共6页
In a scale-free network, only a minority of nodes are connected very often, while the majority of nodes are connected rarely. However, what is the ratio of minority nodes to majority nodes resulting from the Matthew e... In a scale-free network, only a minority of nodes are connected very often, while the majority of nodes are connected rarely. However, what is the ratio of minority nodes to majority nodes resulting from the Matthew effect? In this paper, based on a simple preferential random model, the poor-rich demarcation points are found to vary in a limited range, and form a poor-rich demarcation interval that approximates to k/m E [3,4]. As a result, the (cumulative) degree distribution of a scale-free network can be divided into three intervals: the poor interval, the demarcation interval and the rich interval. The inequality of the degree distribution in each interval is measured. Finally, the Matthew effect is applied to the ABC analysis of project management. 展开更多
关键词 Matthew effect scale-free networks poor-rich demarcation project management
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The Dilemma of Scientific Demarcation and Its Possible Approach
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作者 Wenyan Lu 《Journal of Educational Theory and Management》 2020年第2期19-23,共5页
From logicism to historicism,philosophers of science have put forward different standards of scientific demarcation according to their own scientific views.However,these standards encounter problems either in theory o... From logicism to historicism,philosophers of science have put forward different standards of scientific demarcation according to their own scientific views.However,these standards encounter problems either in theory or in practice,and then fall into difficulties,thus moving towards relativism.Philosophy of scientific practice has reversed the previous image of science with scientific practice and pointed out the temporality,dynamics and locality of science.Therefore,the scientific boundary under this approach also has the above characteristics.Besides,the scientific boundary constructed by the scientific image is developmental and features temporary stability and effectiveness.Scientific demarcation is not a purely epistemological problem,but also a practical one. 展开更多
关键词 Scientific demarcation Philosophy of scientific practice PRACTICE
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Global Calibration Method for Monocular Multi-View System Using Rotational Dual-Target
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作者 Kun He Hongwei He 《Open Journal of Applied Sciences》 2024年第5期1192-1203,共12页
To make the problems of existing high requirements of calibration tools, complex global calibration process addressed for monocular multi-view visual measurement system during measurement, in the paper, a global calib... To make the problems of existing high requirements of calibration tools, complex global calibration process addressed for monocular multi-view visual measurement system during measurement, in the paper, a global calibration method is proposed for the geometric properties of rotational correlation motion and the absolute orientation of the field of view without over lap. Firstly, a dual-camera system is constructed for photographing and collecting the rotating image sequence of two flat targets rigidly connected by a long rod at different positions, and based on the known parameters, such as, target feature image, world coordinates, camera internal parameters and so on, then the global PnP optimization method is used to solve the rotation axis and the reference point at different positions;Then, the absolute orientation matrix is constructed based on the parameters of rotation axis, reference point and connecting rod length obtained by this method. In the end, the singular value decomposition method is used to find the optimal rotation matrix, and then get the translation matrix. It’s shown based on simulation and actual tests that in comparison with the existing methods, the maximum attitude and pose errors is 0.0083˚ and 0.3657 mm, respectively, which improves the accuracy by 27.8% and 24.4%, respectively. The calibration device in this paper is simple, and there are no parallel, vertical and coplanar requirements between multiple rotating positions. At the same time, in view of the calibration accuracy, the accuracy requirements of most application scenarios can be met. 展开更多
关键词 Machine Vision Accurate Demarcating Global Calibration Absolute Orientation
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Delineation of Prospecting Prospect Area Based on Maximum Entropy Model
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作者 Zhen Chen Lianwu Shi 《Journal of Geoscience and Environment Protection》 2023年第11期27-40,共14页
Taking the Dapingzhang copper-polymetallic deposit in Yunnan Province, China as the research object, the maximum entropy model was used to extract the mining information, and the mineral resource prediction model was ... Taking the Dapingzhang copper-polymetallic deposit in Yunnan Province, China as the research object, the maximum entropy model was used to extract the mining information, and the mineral resource prediction model was established by using the exploration data of the deposit and related regions in this area, so as to determine the prospecting prospect area in the study area. In this paper, the Jacknife analysis module of maximum entropy model is used to quantitatively rank the importance of 39 geochemical element variables, and finally obtain the prospecting prospect map of the study area. The research results show that the Dapingzhang mining area has the potential to find hidden ore in the deep and surrounding areas, and the northern and southern ends and western sides of the rock ore control structural belt in the eastern region of the mining area have good prospecting prospects. The research results provide an important basis for the deployment of follow-up exploration work in the study area, and the maximum entropy model has a good application effect in mineral resources exploration. 展开更多
关键词 Target Area demarcation Peripheral and Deep Exploration Maximum Entropy Exploration and Prediction Geological Big Data
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A case of neuroendocrine tumor G1 with unique histopathological growth progress 被引量:1
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作者 Misuzu Hirai Kenshi Matsumoto +6 位作者 Hiroya Ueyama Hirohumi Fukushima Takashi Murakami Hitoshi Sasaki Akihito Nagahara Takashi Yao Sumio Watanabe 《World Journal of Gastrointestinal Endoscopy》 CAS 2013年第12期605-609,共5页
A gastric neuroendocrine tumor(NET)is generated from deep within the tissue mucosal layers.In many cases,NETs are discovered as submucosal tumor(SMT)-like structures by forming a tumor mass.This case has a clear mucos... A gastric neuroendocrine tumor(NET)is generated from deep within the tissue mucosal layers.In many cases,NETs are discovered as submucosal tumor(SMT)-like structures by forming a tumor mass.This case has a clear mucosal demarcation line and developed like a polyp.A dilated blood vessel was found on the surface.The mass lacked the yellow color characteristic of NETs,and a SMT-like form was evident.Therefore,a nonspecific epithelial lesion was suspected and we performed endoscopy with magnifying narrowband imaging(M-NBI).However,this approach did not lead to the diagnosis,as we diagnosed the lesion as a NET by biopsy examination.The lesion was excised by endoscopic submucosal dissection.The histopathological examination proved that the lesion was a polypoid lesion although it was also a NET because the tumorcells extended upward through the normal gland ducts scatteredly.To our knowledge,there is no previous report of NET G1 with such unique histopathological growth progress and macroscopic appearance shown by detailed examination using endoscopy with M-NBI. 展开更多
关键词 Neuroendocrine TUMOR G1 demarcation line POLYPOID GROWTH Magnifying narrow-band imag-ing SUBMUCOSAL TUMOR
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Delineating forest stands from grid data 被引量:1
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作者 Timo Pukkala 《Forest Ecosystems》 SCIE CSCD 2020年第3期301-314,共14页
Background: Forest inventories are increasingly based on airborne laser scanning(ALS). In Finland, the results of these inventories are calculated for small grid cells, 16 m by 16 m in size. Use of grid data in forest... Background: Forest inventories are increasingly based on airborne laser scanning(ALS). In Finland, the results of these inventories are calculated for small grid cells, 16 m by 16 m in size. Use of grid data in forest planning results in the additional requirement of aggregating management prescriptions into large enough continuous treatment units. This can be done before the planning calculations, using various segmentation techniques, or during the planning calculations, using spatial optimization. Forestry practice usually prefers reasonably permanent segments created before planning. These segments are expected to be homogeneous in terms of site properties, growing stock characteristics and treatments. Recent research has developed methods for partitioning grids of ALS inventory results into segments that are homogeneous in terms of site and growing stock characteristics. The current study extended previous methods so that also the similarity of treatments was considered in the segmentation process.The study also proposed methods to deal with biases that are likely to appear in the results when grid data are aggregated into large segments.Methods: The analyses were conducted for two datasets, one from southern and the other from northern Finland.Cellular automaton(CA) was used to aggregate the grid cells into segments using site characteristics with(1)growing stock attributes interpreted from ALS data,(2) predicted cutting prescriptions and(3) both stand attributes cutting prescriptions. The CA was optimized for each segmentation task. A method based on virtual stands was used to correct systematic errors in variable estimates calculated for segments.Results: The segmentation was rather similar in all cases. The result is not surprising since treatment prescriptions depend on stand attributes. The use of virtual stands decreased biases in growth prediction and in the areas of different fertility classes.Conclusions: Automated stand delineation was not sensitive to the type of variables that were used in the process.Virtual stands are an easy method to decrease systematic errors in calculations. 展开更多
关键词 Cellular automata SEGMENTATION Stand demarcation Particle swarm optimization
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On an Axiomatic Foundation for a Theory of Everything 被引量:1
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作者 CUI Weicheng 《Journal of Philosophy Study》 2021年第4期241-267,共27页
Whether a unified theory of everything(TOE)is possible or not is a philosophical question and yes or no can be chosen in a two-valued logic system.Currently the two schools are in conflict with each other.Based on the... Whether a unified theory of everything(TOE)is possible or not is a philosophical question and yes or no can be chosen in a two-valued logic system.Currently the two schools are in conflict with each other.Based on the relativity of simultaneity axiom proposed in this paper,the present author suggests to use a midway philosophy to replace the present materialist philosophy for modern sciences;then this conflict together with many other conflicts among different theories such as classical mechanics(CM),general relativity(GR),and quantum mechanics(QM)can be solved and a unified theory of everything for the world we can observe can be constructed.In this paper,the axiomatic foundation for a TOE is proposed which contains six fundamental axioms.Various problems related to these foundational issues are discussed.It is hoped that the present paper might show a new promise and a new direction for TOE which would be helpful for the further development of modern sciences. 展开更多
关键词 AXIOM mind-body problem the demarcation problem cause-effect law theory of everything(TOE)
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Methods and procedures to determine the outer limits of the continental shelf beyond 200 nautical miles
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作者 WU Ziyin LI Jiabiao +3 位作者 JIN Xianglong FANG Yinxia SHANG Jihong LI Shoujun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第12期126-132,共7页
This paper establishes techniques and methods to determine a variety of boundaries associated with 200 nautical miles beyond the continental shelf. The methods, based on topography, slope and second-deriv- ative profi... This paper establishes techniques and methods to determine a variety of boundaries associated with 200 nautical miles beyond the continental shelf. The methods, based on topography, slope and second-deriv- ative profile integrated analysis, are now able to identify automatically the foot of the continental slope (FOS). By analyzing the sedimentary profile, the points of 1% sediment thickness are recognized. Through the intersection, cut, deletion and mergence calculation of the extrapolated data set of fLxed-point series, the method succeeds in generating automatically the extrapolated boundaries, including the FOS+60 M line, the 350 M line, and the 2500 m+100 M line. In addition, based on the automatic analysis of the topographic profile, it can be applied to determine rapidly the points of maximum water depth. Taking the northern Okinawa Trough (OT) as an example, these methods are used to calculate and examine the boundaries in- cluded in the Submission by the People's Republic of China Concerning the Outer Limits of the Continental Shelf beyond 200 Nautical miles in Part of the East China Sea (ECS); the boundaries thus derived have a solid scientific and rational basis. 展开更多
关键词 200 nautical miles continental shelf demarcation METHODOLOGY Okinawa Trough
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Research on Recognition of Color Landmark
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作者 冯秉瑞 黄庆明 +2 位作者 杨威 刘英健 张田文 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第4期25-29,共5页
ResearchonRecognitionofColorLandmarkFENGBingruiHUANGQingmingYANGWeiLIUYingjianZHANGTianwen(冯秉瑞)(黄庆明)(杨威)(刘英健... ResearchonRecognitionofColorLandmarkFENGBingruiHUANGQingmingYANGWeiLIUYingjianZHANGTianwen(冯秉瑞)(黄庆明)(杨威)(刘英健)(张田文)(Dept.ofCom... 展开更多
关键词 COLOR image SEGMENTATION NEURAL net LANDMARK RECOGNITION COLOR demarcation
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An exemplification of the Evolving Process by Studying the Chinese Character Mao
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作者 周吉红 伍光琴 《海外英语》 2013年第21期294-296,共3页
This paper tries to demarcate the evolving process of decategorization into three periods and exemplify it by studying the Chinese character Mao.The exemplification shows the correctness of the demarcation.
关键词 DECATEGORIZATION attributes demarcate Chinese CHAR
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Dispersion of the Bacterium Xylella fastidiosa in Portugal
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作者 Carla Carvalho-Luis JoséManuel Rodrigues Luís M.Martins 《Journal of Agricultural Science and Technology(A)》 2022年第1期35-41,共7页
After the first detection of the gram-negative bacterium,Xylella fastidiosa multiplex in Portugal,in January 2019,a“Demarcated Area”was delimited and an“Action Plan”to control the pathogen has been developed.It is... After the first detection of the gram-negative bacterium,Xylella fastidiosa multiplex in Portugal,in January 2019,a“Demarcated Area”was delimited and an“Action Plan”to control the pathogen has been developed.It is considered one of the greatest threats to plant health worldwide and leads to loss of forests vitality and productivity.The current study was developed till June 2020,with the objective to understand the dimension of the issue worldwide and in Portugal,analyzing the state-of-the-art on the biology,dispersion,symptoms,control and risks associated with this bacterium(Research Phase).In the Prospecting Phase,we collected 5 branches with 5-8 leaves,from the four quadrants of the tree,wrapping and labeling them-so 2,261 samples were collected and sent to the laboratory for analysis.It was possible to determine that the two initial outbreaks were not an isolated case,as 107 additional outbreaks were detected in other places,revealing a much more worrying panorama,requiring further analysis on the real impact of this bacterial strain on the natural environment.By the end of this study the demarcated area covered about 62,000 ha.The most affected species was lavender with 30%of positive outbreaks,followed by gorse with 22%,and rosemary with 11%.Spread of Phillaenus spumarius and X.fastidiosa indicates that insect vector and transport links appear to be dispersal facilitators together with Douro River.As eradication is unfeasible to achieve in the coming years,containment will be the most appropriate strategy. 展开更多
关键词 PHYTOPATHOGEN forest plant health xylem-limited BACTERIA Xylella fastidiosa multiplex biotic stressors Demarcated Area
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The gas recovery of water-drive gas reservoirs
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作者 李闽 李滔 +2 位作者 蒋琼 杨海 刘世常 《Journal of Hydrodynamics》 SCIE EI CSCD 2015年第4期530-541,共12页
This paper proposes a method for determining the gas recovery of water-drive gas reservoirs. First, the water influx coefficient B in the theoretical formula Pr =(1-Rg)/(1-RgB) is used to determine the influence o... This paper proposes a method for determining the gas recovery of water-drive gas reservoirs. First, the water influx coefficient B in the theoretical formula Pr =(1-Rg)/(1-RgB) is used to determine the influence of the aquifer behavior. According to the theoretical formula, the relationship between the norrnalized pressure Pr and the degree of the reserve recovery Rg can be obtained with different values of B, which can be used to determine the activity level of the aquifer behavior. Second, according to Pra = (1-Rga)/(1-aEva) (where a = 1-Sgr/Sgi ), the relationship between the normalized abandonment pressure Pra and the ultimate gas recovery Rga can be obtained, as the Agarwal end-point line. The intersection of the above two lines represents the value of the estimated ultimate gas recovery and the normalized abandonment pressure pra. Finally, an evaluation table and a set of demarcation charts are established, with different values of Sgr/Sgi and Eva as well as the water influx coefficient B, which can be used to determine the gas recovery of water-drive gas reservoirs with different activity levels of the aquifer behavior. 展开更多
关键词 water-drive gas reservoirs degree of reserve recovery water influx coefficient evaluation table demarcation charts
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Israel’s Mediterranean Gas Governance:Evolution of Domestic Regulations and Emerging Regional Issues
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作者 Sujata ASHWARYA 《Asian Journal of Middle Eastern and Islamic Studies》 2017年第4期76-99,I0006,共25页
In recent years,Israel has discovered commercially viable natural gas deposits in what the state considers its exclusive economic zone(EEZ)in the Eastern Mediterranean.While these gas discoveries constitute less than ... In recent years,Israel has discovered commercially viable natural gas deposits in what the state considers its exclusive economic zone(EEZ)in the Eastern Mediterranean.While these gas discoveries constitute less than 2%of the world’s proven gas reserves,they have the potential to not only meet Israel’s energy needs for several years to come but also enable Israel to export some amount of gas to neighboring countries as well as transregionally,to Europe.While these maritime gas fields have transformed Israel-from energy deficient to energy surplus country-Israeli policymakers are confronted with three main challenges-the revamping of taxation rules,allocation of an export quota for export,and the introduction of competition in the energy sector.The potential for export of gas presents Israel with both opportunities and challenges.While the possibilities include export to Egypt,Turkey and Europe,earning a significant monetary dividend for Israel,problems include territorial disputes and contesting claims over resources among regional countries.The gas supply to Jordanian companies is the only favorable trade deal yet for Israeli field developers.In the absence of differentiation of the exclusive economic zones in the Eastern Mediterranean region,given the political disputes between Turkey and Cyprus and Israel and Lebanon,Israeli gas export ideas may not materialize anytime soon. 展开更多
关键词 Israel’s Gas Regulatory Framework Gas Export Pipeline Options Risk of Conflict demarcation of EEZs
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Modelling of dynamic recrystallization kinetics of 300M steel at high strain rates during hot deformation 被引量:6
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作者 GUO Peng DENG Lei +1 位作者 WANG XinYun LI JianJun 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2019年第9期1534-1544,共11页
The flow curves of 300M steel exhibit a transition from stress peak presence to stress peak absence as the strain rate increases. It is difficult to establish dynamic recrystallization(DRX) kinetics models suitable fo... The flow curves of 300M steel exhibit a transition from stress peak presence to stress peak absence as the strain rate increases. It is difficult to establish dynamic recrystallization(DRX) kinetics models suitable for strain rates where there are no stress peaks in the flow curves using the existing Avrami equation, and the optimal processing parameters for forging can be scarcely acquired.In this study, the high-temperature flow and DRX behavior of 300M steel are investigated by performing isothermal compression tests at temperatures between 1173–1423K with strain rates between 0.001–50 s-1. Distinct stress peaks can be found in the flow curves at low strain rates, and the average grain size decreases with the increase in the strain rate at the same temperature. The DRX mechanism is a discontinuous DRX, and the grain boundary migration plays an important role in the DRX process. In contrast, no stress peak is observed in the flow curves at high strain rates, and the average grain size no longer decreases with the strain rate increase at the same temperature. The DRX mechanism in this case is a continuous DRX. The demarcated strain rate is calculated based on the characteristics of the obtained flow curves and grain sizes. The recrystallization volume fraction model and prediction grain size model at high strain rates are established. In combination with the existing DRX kinetics models at low strain rates, the processing parameters can be optimized to produce components with excellent mechanical properties. 展开更多
关键词 300M steel flow CURVES demarcated strain rate dynamic RECRYSTALLIZATION GRAIN size
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