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Unbiased Estimation Formula of Unit Weight Standard Deviation in Regularization Solution 被引量:1
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作者 SHENYunzhong LIUDajie 《Geo-Spatial Information Science》 2004年第3期210-213,共4页
Regularization method is an effective method for solving ill\|posed equation. In this paper the unbiased estimation formula of unit weight standard deviation in the regularization solution is derived and the formula i... Regularization method is an effective method for solving ill\|posed equation. In this paper the unbiased estimation formula of unit weight standard deviation in the regularization solution is derived and the formula is verified with numerical case of 1 000 sample data by use of the typical ill\|posed equation, i.e. the Fredholm integration equation of the first kind. 展开更多
关键词 regularization solution unit weight standard deviation unbiased estimation
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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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Quality Analysis and Evaluation of Maize Cultivars Approved by Shanxi Province 被引量:3
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作者 智建奇 武海丽 +3 位作者 马淑文 赵力 赵鑫 焦建伟 《Agricultural Science & Technology》 CAS 2016年第3期555-560,共6页
[Objective] This study aimed to provide a theoretical basis for the genetic improvement of maize quality in Shanxi Province. [Method] The variations in unit weight, crude starch content, crude protein content, crude f... [Objective] This study aimed to provide a theoretical basis for the genetic improvement of maize quality in Shanxi Province. [Method] The variations in unit weight, crude starch content, crude protein content, crude fat content and lysine content of maize cultivars approved by Shanxi Province during 2003-2012 were analyzed. [Result] In Shanxi Province, the average unit weight and crude starch content of maize cultivars approved during 2003-2012 were trended to be increased;the crude fat contents of maize cultivars approved during 2003-2012 showed no significant changes; the lysine contents of maize cultivars approved during 2003-2008 were essentially unchanged; the crude protein contents of maize cultivars approved during 2003-2012 declined slightly. [Conclusion] The crude starch content and unit weight of maize increased with the increased yield; the crude protein content, crude fat content and lysine content showed certain stability, and they were mainly controlled by genes. Therefore, the breeding of particular maize should be strengthened. 展开更多
关键词 MAIZE Crude protein content Crude fat content Crude starch content Lysine content Unit weight
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Properties of the total least squares estimation 被引量:3
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作者 Wang Leyang 《Geodesy and Geodynamics》 2012年第4期39-46,共8页
Through theoretical derivation, some properties of the total least squares estimation are found. The total least squares estimation is the linear transformation of the least squares estimation, and the total least squ... Through theoretical derivation, some properties of the total least squares estimation are found. The total least squares estimation is the linear transformation of the least squares estimation, and the total least squares estimation is unbiased. The condition number of the total least squares estimation is greater than the least squares estimation, so the total least squares estimation is easier to be affected by the data error than the least squares estimation. Then through the further derivation, the relationships of solutions, residuals and unit weight variance estimations between the total least squares and the least squares are given. 展开更多
关键词 total least squares (TLS) least squares (LS) singular value decomposition (SVD) RESIDUALS unit weight variance
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Fuzzy Earthwork Dynamic Allocation and Optimization for Construction of High Concrete Face Rockfill Dam 被引量:2
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作者 刘宁 崔博 钟登华 《Transactions of Tianjin University》 EI CAS 2012年第6期426-431,共6页
Due to the complexity of earthwork allocation system for the construction of high concrete face rockfill dam,traditional allocation and planning are not able to function properly in the construction process with stron... Due to the complexity of earthwork allocation system for the construction of high concrete face rockfill dam,traditional allocation and planning are not able to function properly in the construction process with strong randomness.In this paper,the working mechanism of earthwork dynamic allocation system is analyzed comprehensively and a solution to fuzzy earthwork dynamic allocation is proposed on the basis of uncertain factors in the earthwork allocation of a hydropower project.Under the premise of actual situation and the experience of the construction site,an all-coefficient-fuzzy linear programming mathematical model with fuzzy parameters and constraints for earthwork allocation is established according to the structure unit weighted ranking criteria.In this way,the deficiency of certain allocation model can be overcome.The application results indicate that the proposed method is more rational compared with traditional earthwork allocation. 展开更多
关键词 high concrete face rockfill dam fuzzy number earthwork dynamic allocation structure unit weighted ranking
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Anti-interference Strategy of 20-Hi Cold Mill Automatic Gauge Control
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作者 ZHANG Zhen ZHU Bingquan CHEN Haifeng 《Instrumentation》 2022年第3期10-18,共9页
Automatic gauge control(AGC in the article)is the key technology of product thickness accuracy and flatness quality in modern cold rolling mill.Most traditional AGC control algorithms need stable external system condi... Automatic gauge control(AGC in the article)is the key technology of product thickness accuracy and flatness quality in modern cold rolling mill.Most traditional AGC control algorithms need stable external system conditions and hard to stabilize under complex interference that meets coverage requirements.This paper presents a new anti-interference strategy for AGC control of 20-Hi cold reversing mill.The proposed algorithm introduces a united dynamic weights algorithm of feed forward-mass flow to avoid the complex interference problem in AGC control,the relevant control strategy is provided to eliminate the adverse effects.At the same time,the D-value between feed forward-mass flow pre-computation and thickness measurement deviation is dynamic compared,the final gap position regulation is calculated by developing a set of united dynamic weights between feed forward control and mass flow control.Finally,the output of controllers is sent to actuator though a constant rate smoothing.The proposed strategy is compared with conventional AGC control on Experimental platform and project application,the results show that the proposed strategy is more stable than comparison method and majority of system uncertainty produced by mentioned interference is significantly eliminated. 展开更多
关键词 20-Hi Cold Mill Complex Interference AGC Control united Dynamic weights ANTI-INTERFERENCE
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EFFECTS OF CONSOLIDATION TIME AND PARTICLE SIZE ON SCOUR RATES OF COHESIVE SEDIMENT 被引量:11
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作者 TAN Guang-ming WANG Jun SHU Cai-wen LAI Yong-hui 《Journal of Hydrodynamics》 SCIE EI CSCD 2007年第2期160-164,共5页
By means of flumes, experiments have been done in order to determine the effects of consolidation time and particle size on scour rates of cohesive sediment. Experimental results shown dry unit weight increased and sc... By means of flumes, experiments have been done in order to determine the effects of consolidation time and particle size on scour rates of cohesive sediment. Experimental results shown dry unit weight increased and scour rates decreased during the course of consolidation, the resistance to scour was related to consolidation time, but it presented different consolidation properties that depended on particle size. For the finer particle, the consolidation process was longer, the range of dry unit weight altered was greater, the consolidated sediments moved in chunks. On the other hand, based on analysis of the relationship of dry unit weight change with consolidation time, the simplified analytical expressions of dry unit weight and scour rates were derived, the results were checked with experimental data in the same flow situation and good agreements were achieved. Since the effects of different particle size were considered during the process of consolidation, the variations of consolidation properties were well reflected in these formulas. 展开更多
关键词 cohesive sediment scour rates consolidation time dry unit weight
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