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Grindability Evaluation of Ultrasonic Assisted Grinding of Silicon Nitride Ceramic Using Minimum Quantity Lubrication Based SiO_(2)Nanofluid 被引量:2
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作者 Yusuf Suleiman Dambatta Changhe Li +8 位作者 Mohd Sayuti Ahmed A D Sarhan Min Yang Benkai Li Anxue Chu Mingzheng Liu Yanbin Zhang Zafar Said Zongming Zhou 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期115-136,共22页
Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL ... Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL system is affirmed to exhibit an excellent machining performance,and it is highly economical.The nanofluids are understood to exhibit excellent lubricity and heat evacuation capability,compared to pure oil-based MQL system.Studies have shown that the surface quality and amount of energy expended in the grinding operations can be reduced considerably due to the positive effect of these nanofluids.This work presents an experimental study on the tribological performance of SiO_(2)nanofluid during grinding of Si_(3)N_(4)ceramic.The effect different grinding modes and lubrication systems during the grinding operation was also analyzed.Different concentrations of the SiO_(2)nanofluid was manufactured using canola,corn and sunflower oils.The quantitative evaluation of the grinding process was done based on the amount of grinding forces,specific grinding energy,frictional coefficient,and surface integrity.It was found that the canola oil exhibits optimal lubrication performance compared to corn oil,sunflower oil,and traditional lubrication systems.Additionally,the introduction of ultrasonic vibrations with the SiO_(2)nanofluid in MQL system was found to reduce the specific grinding energy,normal grinding forces,tangential grinding forces,and surface roughness by 65%,57%,65%,and 18%respectively.Finally,regression analysis was used to obtain an optimum parameter combinations.The observations from this work will aid the smooth transition towards ecofriendly and sustainable machining of engineering ceramics. 展开更多
关键词 Minimum quantity lubrication(MQL) Ultrasonic assisted grinding(UAG) Eco-friendly lubricants NANofLUID GRINDING CERAMIC
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The Effect of Mineral Composition and Quantity of Fines on the Atterberg Limits and Compaction Characteristics of Soils
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作者 Abdalhamid Musbah Muad Mohammed Adem Alfghia 《Open Journal of Civil Engineering》 2024年第2期258-276,共19页
Because of the various elements that come into play in natural soil formation, the impact of varied proportions of mineral composition and fines amount on Atterberg limits and compaction characteristics of soils is no... Because of the various elements that come into play in natural soil formation, the impact of varied proportions of mineral composition and fines amount on Atterberg limits and compaction characteristics of soils is not well known. Three distinct soil samples were used in this investigation. The findings indicated the effect of varied mineral composition proportions and fines amount on the liquid limit, plastic limit, and plasticity index as assessed by the Casagrande test and hand-rolling method. The fluctuation of maximum dry density and optimal moisture content with these three soils has also been studied. Furthermore, correlations were established to indicate the compaction parameters and the amount of minerals and particles in the soil. The data show that the mineral content of the soil has a direct impact on the Atterberg limits and compaction characteristics. Soils containing larger percentages of expansive minerals, such as montmorillonite, have more flexibility and volume change capability. Mineral composition influences compaction parameters such as maximum dry density, ideal water content, axial strain, and axial stress. Soils with a larger proportion of fines, such as Soil 2 and Soil 3, have stronger flexibility and lower compaction qualities, with higher ideal water content and lower maximum dry density. Soil 1 has moderate flexibility and intermediate compaction qualities due to its low fines percentage. The effect of different mineral compositions and fines on the Atterberg limits and compaction characteristics of soils can be used to predict the behavior of compacted soils encountered in engineering practices, reducing the time and effort required to assess soil suitability for engineering use. 展开更多
关键词 Atterberg Limit Mineral Composition quantity of Fines Maximum Dry Unit Weight Optimum Water Content
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Quantity of plant leaf area on three major public squares in Kunming City, China 被引量:8
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作者 董燕 赵林森 赵宇翔 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期291-294,共4页
Regressive formulae to calculate the quantity of plant leaf area for 13 species of ornamental plants were set up based on investigation data of 30 species on 3 major public squares (Dongfeng square, Shengli square and... Regressive formulae to calculate the quantity of plant leaf area for 13 species of ornamental plants were set up based on investigation data of 30 species on 3 major public squares (Dongfeng square, Shengli square and Guandu square) in Kun-ming City, China, which were applied to calculate quantities of plant leaf area of these 13 species. The quantities of plant leaf area for the other 17 ornamental plant species on these squares were directly measured, and the total quantity of plant leaf area of each studied square was obtained individually. The results showed that the quantity of plant leaf area on Shengli square with ornamental plants structure composed of arbor tree species, shrub tree species and turf grass was highest among the three squares. It is believed that the design model of multi-storied vertical structure and proper tending of plant community could not only increase the quantity of plant leaf area, but also play an important role in generating ecological and landscaping benefits. Some corresponding suggestions were put forward on the basis of comprehensive analyses on the plant leaf area quantity of the three representative squares in Kunming urban area. 展开更多
关键词 SQUARE Ornamental plants quantity of plant leaf area Kunming
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Comparisons of Nectar Quantity and Sugar Concentration of Pomegranate Blossom in a Day 被引量:1
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作者 余玉生 卢焕仙 +2 位作者 宋文菲 张祖芸 张学文 《Agricultural Science & Technology》 CAS 2013年第1期69-71,共3页
[Objective] The aim was to research the rules of nectar quantity and sugar concentration of perfect and staminate flowers in a day. [Method] Based on nine Tianguang Yan pomegranate trees, nectar quantity and sugar con... [Objective] The aim was to research the rules of nectar quantity and sugar concentration of perfect and staminate flowers in a day. [Method] Based on nine Tianguang Yan pomegranate trees, nectar quantity and sugar concentration of per- fect and staminate flowers were measured and analyzed in morning and afternoon. [Result] Average nectar quantity and sugar concentration differed insignificantly in morning and afternoon of perfect flowers, which could also be applied to staminate flowers. However, average nectar quantity of perfect flower was 64.09 μI and of staminate flower was 44.07 μl. It is obvious that the two were of extremely signifi- cant differences (t=4.642, P〈0.01), and the former was significantly higher by 45,43%. On the other hand, average sugar concentration of perfect flower was 48.44% and of staminate flower was 37.16%. The two were of extremely significant differences and the former is higher by 30.36%, compared with the latter. These suggested that nectar quantity and sugar concentration would maintain unchanged in different periods for a day, if nectars are not consumed by pollinators, such as bees and butterflies. In the same period, nectar quantity and sugar concentration of per- fect flowers were higher than those of staminate flowers. [Conclusion] The research provides references for benefits increase of bee farmers and fruit farmers, as well as exploration of bee pollination. 展开更多
关键词 quantity of secreted nectar Sugar concentration MEASUREMENT Com- parisons
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Effects of Different Land Use Patterns on Soil Microbial Quantity and Activity in Hongta District,Yuxi City 被引量:1
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作者 陈艳 刘家忠 何倩倩 《Agricultural Science & Technology》 CAS 2016年第11期2535-2538,共4页
[Objective] This study aimed to investigate the effects of different land use patterns on soil ecological environment. [Method] Total three representative land use patterns (corn field, cherry tree land, wood land) ... [Objective] This study aimed to investigate the effects of different land use patterns on soil ecological environment. [Method] Total three representative land use patterns (corn field, cherry tree land, wood land) were selected from Hongta District, Yuxi City, and under these three patterns, soil microbial quantity and activity were studied. [Result] Under the three land use patterns, soil microorganisms were domi- nated by bacteria; soil microbial quantity ranked as wood land's〉cheery tree land's〉 corn field's; and total microbial activity, catalase activity and urease activity all ranked as cherry tree land's〉wood land's〉corn field's. [Conclusion] Soil microbial activity and functions are related to farmland management measures, as well as land use pattern and soil nutrients. 展开更多
关键词 Land use pattern Total quantity of microorganisms Microbial activity Hongta District of Yuxi City
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The Immuno-fluorescence Quantity Analysis of α-Tubulin and γ-Tubulin Protein in Precancerous Lesion and Carcinoma of the Breast and Its Significance 被引量:1
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作者 牛昀 张彤文 +3 位作者 王颖 韦丽 魏锡胤 牛瑞芳 《Chinese Journal of Clinical Oncology》 CSCD 2008年第1期16-21,共6页
OBJECTIVE To investigate the changes and values of the expression of α-tubulin and γ-tubulin in atypical ductal hyperplasia (ADH), ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) of the bre... OBJECTIVE To investigate the changes and values of the expression of α-tubulin and γ-tubulin in atypical ductal hyperplasia (ADH), ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) of the breast. The relationship between centrosome abnormalities and breast tumor development was further discussed. METHODS There were three groups including ADH, DCIS and IDC with 30 cases in each group. They were analyzed by immuno-fiuorescence quantity analysis. The expression levels of α-tubulin and γ-tubulin protein in these tissues were detected by flow cytometry immuno-fiuorescence analysis and compared with the results from normal tissues. Immunohistochemistry was also performed in this research. RESULTS The results showed significant differences of the average of the positive (FITC labeled) cells (P=0.000) among the four groups. The level of the IDC group was the highest, while normal breast tissue showed the lowest level. The results suggested that the expression levels of α-tubulin and γ-tubulin both increased as the grade of cellular proliferation and differentiation increased. The expressions showed significant differences among all the groups, except between the ADH and DCIS. There were no significant differences between α-tubulin and γ-tubulin expression in each group (P〈0.05), as there was agreement in the immuno-fluorescence and immunohistochemical analysis for protein expression. CONCLUSION There is abnormal expression of centrosome tubulin as an early event in the development of breast tumor. Furthermore these aberrations may play a key role during oncogenesis and promote cellular transformation to malignancy. The immuno-fiuorescence quantitive analysis and immunohistochemistry can complement each other. 展开更多
关键词 centrosome α-tubulin protein centrosome γ-tubulin protein precancerous lesion breast carcinoma immuno-fluorescence quantity analysis.
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Research of an Appropriate Sowing Quantity of Double-cropping Machine-transplanted Rice in Low and Medium Yielding District of Southern Jiangxi Province
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作者 钟珺 胡启锋 +4 位作者 李云 黎为兵 连垚 张朝阳 虞新华 《Agricultural Science & Technology》 CAS 2016年第3期526-529,543,共5页
[Objective] The aim was to research the appropriate seeding quantities of double-season machine-transplanted rice in middle and low-yielding district of southern Jiangxi Province. [Method] The research set five differ... [Objective] The aim was to research the appropriate seeding quantities of double-season machine-transplanted rice in middle and low-yielding district of southern Jiangxi Province. [Method] The research set five different seeding quantities treatments, and compared with conventional seedling treatment, and the appropriate seeding quantities of double season machine-transplanted rice in middle and lowyielding district of southern Jiangxi Province was discussed. [Result] The yields were highest when the seeding quantity was 70 g per tray of early rice by mechanical transplanting and 60 g per tray of late rice. The yield of early rice by mechanical transplanting showed significantly positive correlation with the number of productive ear and the number of seed per ear, and late rice yield showed significant correlation with the number of productive ear by mechanical transplanting. It is key for improving high yields by guaranteeing the number of productive ear. [Conclusion] The issue of proper sowing quantity should be taken into consideration for double-cropping rice in the region, which is crucial for high yields. 展开更多
关键词 Sowing quantity Double-cropping rice Machine-transplanted Rice Low and medium yielding farmlands
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Test and Research of Total Quantity of N and P Fertilizers for Maize
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作者 于立芝 叶明国 +2 位作者 王雁 于海 姜新 《Agricultural Science & Technology》 CAS 2015年第4期755-756,773,共3页
Objective] The alm was to provide scientific references for determination of optimal N and P quantities of malze. [Method] The research conducted a test in field to expIore the effects of N and P fertiIizers on malze ... Objective] The alm was to provide scientific references for determination of optimal N and P quantities of malze. [Method] The research conducted a test in field to expIore the effects of N and P fertiIizers on malze yield. [Result] Both of N and P fertiIizers have significant effects on malze yield. When malze yield reached the highest, the quantities of N fertiIizers and P fertiIizers were 530.56 and 105.44 kg/hm2, respectiveIy. [Conclusion] Malze yield keeps growing upon N or P fertiIizers to certaln extent, and excessive quantities of N and P fertiIizer wouId reduce malze yield. 展开更多
关键词 Malze N fertliizer P fertliizer ControI test of total fertliizer quantity
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Type, quantity and layout of urban peripheral green space 被引量:1
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作者 王晓俊 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第1期67-70,共5页
Urban peripheral green space (UPGS) plays more and more important rol e in sustaining urban physical and ecological environments. In this paper, a pre liminary classification of UPGS was presented for seven types and ... Urban peripheral green space (UPGS) plays more and more important rol e in sustaining urban physical and ecological environments. In this paper, a pre liminary classification of UPGS was presented for seven types and quantity index of UPGS was discussed tentatively. The quantity and layout problems in urban pe ripheral green space, and the several principles were mainly discussed in urban ventilation and sanitation, recreational opportunity and landscape ecological st ructure. 展开更多
关键词 PERIPHERAL Green space quantity Layout
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A symmetry and a conserved quantity for the Birkhoff system 被引量:11
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作者 梅凤翔 江铁强 解加芳 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第8期1678-1681,共4页
A symmetry and a conserved quantity of the Birkhoff system are studied. The symmetry is called the Birkhoff symmetry. Its definition and criterion are given in this paper. A conserved quantity can be deduced by using ... A symmetry and a conserved quantity of the Birkhoff system are studied. The symmetry is called the Birkhoff symmetry. Its definition and criterion are given in this paper. A conserved quantity can be deduced by using the symmetry. An example is given to illustrate the application of the result. 展开更多
关键词 Birkhoff system SYMMETRY conserved quantity
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Symmetry and Hojman Conserved Quantity of Tznoff Equations for Unilateral Holonomic System 被引量:12
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作者 ZHENG Shi-Wang Department of Physics and Information Engineering,Shangqiu Teachers College,Shangqiu 476000,ChinaXIE Jia-Fang Department of Mechanics,Beijing Institute of Technology,Beijing 100081,ChinaJIA Li-Qun College of Science,Southern Yangtze University,Wuxi 214122,China 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第7期43-47,共5页
Symmetry of Tzénoff equations for unilateral holonomic system under the infinitesimal transformationsof groups is investigated.Its definitions and discriminant equations of Mei symmetry and Lie symmetry of Tz... Symmetry of Tzénoff equations for unilateral holonomic system under the infinitesimal transformationsof groups is investigated.Its definitions and discriminant equations of Mei symmetry and Lie symmetry of Tzénoffequations are given.Sufficient and necessary condition of Lie symmetry deduced by the Mei symmetry is also given.Hojman conserved quantity of Tzénoff equations for the system above through special Lie symmetry and Lie symmetryin the condition of special Mei symmetry respectively is obtained. 展开更多
关键词 unilateral constraint Tzénoff equations SYMMETRY Hojman conserved quantity
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A new type of conserved quantity of Mei symmetry for the motion of mechanico electrical coupling dynamical systems 被引量:12
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作者 赵丽 傅景礼 陈本永 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期1-4,共4页
We obtain a new type of conserved quantity of Mei symmetry for the motion of mechanico--electrical coupling dynamical systems under the infinitesimal transformations. A criterion of Mei symmetry for the mechanico-elec... We obtain a new type of conserved quantity of Mei symmetry for the motion of mechanico--electrical coupling dynamical systems under the infinitesimal transformations. A criterion of Mei symmetry for the mechanico-electrical coupling dynamical systems is given. Simultaneously, the condition of existence of the new conserved quantity of Mei symmetry for mechanico-electrical coupling dynamical systems is obtained. Finally, an example is given to illustrate the application of the results. 展开更多
关键词 new conserved quantity Mei symmetry mechanico-electrical coupling systems
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Effect of sensor quantity on measurement accuracy of log inner defects by using stress wave 被引量:10
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作者 WANG Li-hai XU Hua-dong ZHOU Ci-lin LI Li YANG Xue-chun 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第3期221-225,共5页
Wood nondestructive testing (NDT) is one of the high efficient methods in utilizing wood. This paper explained the principle of log defect testing by using stress wave, and analyzed the effects of sensor quantity on... Wood nondestructive testing (NDT) is one of the high efficient methods in utilizing wood. This paper explained the principle of log defect testing by using stress wave, and analyzed the effects of sensor quantity on defect testing results by using stress wave in terms of image fitting degree and error rate. The results showed that for logs with diameter ranging from 20 to 40 cm, at least 12 sensors were needed to meet the requirement which ensure a high testing accuracy of roughly 90% of fitness with 0.1 of error rate. And 10 sensors were recommended to judge the possible locations of defects and 6 sensors were sufficient to decide whether there were defects or not. 展开更多
关键词 Sensor quantity Log defect testing Stress wave Image fitting degree
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A new type of conserved quantity of Lie symmetry for the Lagrange system 被引量:8
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作者 方建会 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期21-24,共4页
This paper studies a new type of conserved quantity which is directly induced by Lie symmetry of the Lagrange system. Firstly, the criterion of Lie symmetry for the Lagrange system is given. Secondly, the conditions o... This paper studies a new type of conserved quantity which is directly induced by Lie symmetry of the Lagrange system. Firstly, the criterion of Lie symmetry for the Lagrange system is given. Secondly, the conditions of existence of the new conserved quantity as well as its forms are proposed. Lastly, an example is given to illustrate the application of the result. 展开更多
关键词 Lagrange system Lie symmetry new conserved quantity
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Mei symmetry and Mei conserved quantity of nonholonomic systems with unilateral Chetaev type in Nielsen style 被引量:10
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作者 贾利群 解加芳 罗绍凯 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第5期1560-1564,共5页
This paper studies the Mei symmetry and Mei conserved quantity for nonholonomic systems of unilateral Chetaev type in Nielsen style. The differential equations of motion of the system above are established. The defini... This paper studies the Mei symmetry and Mei conserved quantity for nonholonomic systems of unilateral Chetaev type in Nielsen style. The differential equations of motion of the system above are established. The definition and the criteria of Mei symmetry, loosely Mei symmetry, strictly Mei symmetry for the system are given in this paper. The existence condition and the expression of Mei conserved quantity are deduced directly by using Mei symmetry. An example is given to illustrate the application of the results. 展开更多
关键词 Nielsen style unilateral nonholonomic constrained system Mei symmetry Mei conserved quantity
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A new type of conserved quantity of Mei symmetry for Lagrange system 被引量:7
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作者 方健会 丁宁 王鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第4期887-890,共4页
This paper studies a new type of conserved quantity which is directly induced by Mei symmetry of the Lagrange system. Firstly, the definition and criterion of Mei symmetry for the Lagrange system are given. Secondly, ... This paper studies a new type of conserved quantity which is directly induced by Mei symmetry of the Lagrange system. Firstly, the definition and criterion of Mei symmetry for the Lagrange system are given. Secondly, a coordination function is introduced, and the conditions of existence of the new conserved quantity as well as its forms are proposed. Lastly, an illustrated example is given. The result indicates that the coordination function can be selected properly according to the demand for finding the gauge function, and thereby the gauge function can be found more easily. Furthermore, since the choice of the coordination function has multiformity, many more conserved quantities of Mei symmetry for the Lagrange system can be obtained. 展开更多
关键词 Lagrange system Mei symmetry new conserved quantity
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The estimate of sea ice resources quantity in the Bohai Sea based on NOAA/AVHRR data 被引量:18
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作者 YUAN Shuai GU Wei +4 位作者 XU Yingjun WANG Ping HUANG Shuqing LE Zhangyan CONG Jianou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第1期33-40,共8页
The research on sea ice resources is the academic base of sea ice exploitation in the Bohai Sea. According to the ice-water spectrum differences and the correlation between ice thickness and albedo, this paper comes u... The research on sea ice resources is the academic base of sea ice exploitation in the Bohai Sea. According to the ice-water spectrum differences and the correlation between ice thickness and albedo, this paper comes up with a sea ice thickness inversion model based on the NOAA/AVHRR data. And then a sea ice resources quantity (SIQ) time series of Bohai Sea is established from 1987 to 2009. The results indicate that the average error of inversion sea ice thickness is below 30%. The maximum sea ice resources quantity is about 6×109 m3 and the minimum is 1.3×109 m3. And a preliminary analysis has been made on the errors of the estimate of sea ice resources quantity (SIQ). 展开更多
关键词 sea ice in the Bohai Sea sea ice resources quantity NOAA/AVHRR error analysis
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Conformal invariance and conserved quantity of Hamilton systems 被引量:6
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作者 蔡建乐 罗绍凯 梅凤翔 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第9期3170-3174,共5页
This paper studies conformal invariance and conserved quantities of Hamilton system. The definition and the determining equation of conformal invariance for Hamilton system are provided. The relationship between the c... This paper studies conformal invariance and conserved quantities of Hamilton system. The definition and the determining equation of conformal invariance for Hamilton system are provided. The relationship between the conformal invariance and the Lie symmetry are discussed, and the necessary and sufficient condition that the conformal invariance would be the Lie symmetry of the system under the infinitesimal one-parameter transformation group is deduced. It gives the conserved quantities of the system and an example for illustration. 展开更多
关键词 Hamilton system conformal invariance determining equation conserved quantity
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Lie symmetry and conserved quantity of a system of first-order differential equations 被引量:4
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作者 许学军 梅凤翔 张永发 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第1期19-21,共3页
This paper focuses on studying the Lie symmetry and a conserved quantity of a system of first-order differential equations. The determining equations of the Lie symmetry for a system of first-order differential equati... This paper focuses on studying the Lie symmetry and a conserved quantity of a system of first-order differential equations. The determining equations of the Lie symmetry for a system of first-order differential equations, from which a kind of conserved quantity is deduced, are presented. And their general conclusion is applied to a Hamilton system, a Birkhoff system and a generalized Hamilton system. Two examples are given to illustrate the application of the results. 展开更多
关键词 Lie symmetry conserved quantity differential equation mechanical system
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Structure equation and Mei conserved quantity for Mei symmetry of Appell equation 被引量:5
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作者 贾利群 解加芳 郑世旺 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第1期17-22,共6页
This paper investigates structure equation and Mei conserved quantity of Mei symmetry of Appell equations for non-Chetaev nonholonomic systems. Appell equations and differential equations of motion for non-Chetaev non... This paper investigates structure equation and Mei conserved quantity of Mei symmetry of Appell equations for non-Chetaev nonholonomic systems. Appell equations and differential equations of motion for non-Chetaev nonholonomic mechanical systems are established. A new expression of the total derivative of the function with respect to time t along the trajectory of a curve of the system is obtained, the definition and the criterion of Mei symmetry of Appell equations under the infinitesimal transformations of groups are also given. The expressions of the structure equation and the Mei conserved quantity of Mei symmetry in the Appell function are obtained. An example is given to illustrate the application of the results. 展开更多
关键词 Appell equation Mei conserved quantity Mei symmetry non-Chetaev nonholonomic system
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