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雷达干扰未确知效果的测度评价研究 被引量:13
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作者 王瑜 《系统工程与电子技术》 EI CSCD 北大核心 2002年第12期59-61,75,共4页
在未确知数学理论基础上 ,结合电子对抗的特点 ,研究了雷达干扰效果的评价指标体系和度量方法 ,以及如何识别、排序的问题。建立了基于未确知效果测度的雷达干扰效果评价模型 ,并结合有源干扰的一个实例分析 ,获得了较为成功的应用。未... 在未确知数学理论基础上 ,结合电子对抗的特点 ,研究了雷达干扰效果的评价指标体系和度量方法 ,以及如何识别、排序的问题。建立了基于未确知效果测度的雷达干扰效果评价模型 ,并结合有源干扰的一个实例分析 ,获得了较为成功的应用。未确知效果测度评价模型严谨 ,评价结果合理、精细、分辨率高 。 展开更多
关键词 雷达 干扰 未确知效果 测度评价 识别 排序
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Integrating unascertained measurement and information entropy theory to assess blastability of rock mass 被引量:15
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作者 周健 李夕兵 《Journal of Central South University》 SCIE EI CAS 2012年第7期1953-1960,共8页
Due to the complex features of rock mass blastability assessment systems, an evaluation model of rock mass blastability was established on the basis of the unascertained measurement (UM) theory and the actual charac... Due to the complex features of rock mass blastability assessment systems, an evaluation model of rock mass blastability was established on the basis of the unascertained measurement (UM) theory and the actual characteristics of the project. Considering a comprehensive range of intact rock properties and discontinuous structures of rock mass, twelve main factors influencing the evaluation blastability of rock mass were taken into account in the UM model, and the blastability evaluation index system of rock mass was constructed. The unascertained evaluation indices corresponding to the selected factors for the actual situation were solved both qualitatively and quantitatively. Then, the UM function of each evaluation index was obtained based on the initial data for the analysis of the blastability of six rock mass at a highway improvement cutting site in North Wales. The index weights of the factors were calculated by entropy theory, and credible degree identification (CDI) criteria were established according to the UM theory. The results of rock mass blastability evaluation were obtained by the CDI criteria. The results show that the UM model assessment results agree well with the actual records, and are consistent with those of the fuzzy sets evaluation method. Meanwhile, the unascertained superiority degree of rock mass blastability of samples S1-$6 which can be calculated by scoring criteria are 3.428 5, 3.453 3, 4.058 7, 3.675 9, 3.516 7 and 3.289 7, respectively. Furthermore, the proposed method can take into account large amount of uncertain information in blastability evaluation, which can provide an effective, credible and feasible way for estimating the blastability of rock mass. Engineering practices show that it can complete the blastability assessment systematically and scientifically without any assumption by the proposed model, which can be applied to practical engineering. 展开更多
关键词 rock mass BLASTABILITY unascertained measurement (UM) model information entropy PREDICTION
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Unascertained measurement classifying model of goal collapse prediction 被引量:8
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作者 董陇军 彭刚剑 +2 位作者 付玉华 白云飞 刘有芳 《Journal of Coal Science & Engineering(China)》 2008年第2期221-224,共4页
Based on optimized forecast method of unascertained classifying,a unascer- tained measurement classifying model (UMC) to predict mining induced goaf collapse was established,The discriminated factors of the model are ... Based on optimized forecast method of unascertained classifying,a unascer- tained measurement classifying model (UMC) to predict mining induced goaf collapse was established,The discriminated factors of the model are influential factors including over- burden layer type,overburden layer thickness,the complex degree of geologic structure, the inclination angle of coal bed,volume rate of the cavity region,the vertical goaf depth from the surface and space superposition layer of the goaf region.Unascertained mea- surement (UM) function of each factor was calculated.The unascertained measurement to indicate the classification center and the grade of waiting forecast sample was determined by the UM distance between the synthesis index of waiting forecast samples and index of every classification.The training samples were tested by the established model,and the correct rate is 100%.Furthermore,the seven waiting forecast samples were predicted by the UMC model.The results show that the forecast results are fully consistent with the ac- tual situation. 展开更多
关键词 unascertained measurement classifying model GOAF collapse prediction mining engineering
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Ranking method for the reciprocal judgment matrix based on the unascertained three-valued judgments 被引量:4
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作者 Wan Yucheng Ma Baoguo Sheng Zhaohan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第1期115-120,共6页
The ranking problem is studied when the pairwise comparisons values are unoertain in the analytic hierarchy process (AHP). The method of constructing the judgment matrix is presented when the pairwise comparisons va... The ranking problem is studied when the pairwise comparisons values are unoertain in the analytic hierarchy process (AHP). The method of constructing the judgment matrix is presented when the pairwise comparisons values are denoted by the unascertained three-valued reciprocal scales. By turning the reciprocal judgment matrix into attribute judgment matrix, the method to check the consistency of the pairwise comparisons judgment matrix and the calculation method of weighting coefficients are given. Finally, numerical examples are given to illustrate the effectiveness of the proposed method. 展开更多
关键词 AHP UNCERTAINTY unascertained rational number attribute judgment matrix.
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A novel recurrent neural network forecasting model for power intelligence center 被引量:6
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作者 刘吉成 牛东晓 《Journal of Central South University of Technology》 EI 2008年第5期726-732,共7页
In order to accurately forecast the load of power system and enhance the stability of the power network, a novel unascertained mathematics based recurrent neural network (UMRNN) for power intelligence center (PIC) was... In order to accurately forecast the load of power system and enhance the stability of the power network, a novel unascertained mathematics based recurrent neural network (UMRNN) for power intelligence center (PIC) was created through three steps. First, by combining with the general project uncertain element transmission theory (GPUET), the basic definitions of stochastic, fuzzy, and grey uncertain elements were given based on the principal types of uncertain information. Second, a power dynamic alliance including four sectors: generation sector, transmission sector, distribution sector and customers was established. The key factors were amended according to the four transmission topologies of uncertain elements, thus the new factors entered the power intelligence center as the input elements. Finally, in the intelligence handing background of PIC, by performing uncertain and recursive process to the input values of network, and combining unascertained mathematics, the novel load forecasting model was built. Three different approaches were put forward to forecast an eastern regional power grid load in China. The root mean square error (ERMS) demonstrates that the forecasting accuracy of the proposed model UMRNN is 3% higher than that of BP neural network (BPNN), and 5% higher than that of autoregressive integrated moving average (ARIMA). Besides, an example also shows that the average relative error of the first quarter of 2008 forecasted by UMRNN is only 2.59%, which has high precision. 展开更多
关键词 load forecasting uncertain element power intelligence center unascertained mathematics recurrent neural network
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Proposing a novel comprehensive evaluation model for the coal burst liability in underground coal mines considering uncertainty factors 被引量:7
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作者 Jian Zhou Chao Chen +1 位作者 Mingzheng Wang Manoj Khandelwal 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第5期799-812,共14页
Coal burst is a severe hazard that can result in fatalities and damage of facilities in underground coal mines.To address this issue,a robust unascertained combination model is proposed to study the coal burst hazard ... Coal burst is a severe hazard that can result in fatalities and damage of facilities in underground coal mines.To address this issue,a robust unascertained combination model is proposed to study the coal burst hazard based on an updated database.Four assessment indexes are used in the model,which are the dynamic failure duration(DT),elastic energy index(WET),impact energy index(KE)and uniaxial compressive strength(RC).Four membership functions,including linear(L),parabolic(P),S and Weibull(W)functions,are proposed to measure the uncertainty level of individual index.The corresponding weights are determined through information entropy(EN),analysis hierarchy process(AHP)and synthetic weights(CW).Simultaneously,the classification criteria,including unascertained cluster(UC)and credible identification principle(CIP),are analyzed.The combination algorithm,consisting of P function,CW and CIP(P-CW-CIP),is selected as the optimal classification model in function of theory analysis and to train the samples.Ultimately,the established ensemble model is further validated through test samples with 100%accuracy.The results reveal that the hybrid model has a great potential in the coal burst hazard evaluation in underground coal mines. 展开更多
关键词 Coal burst liability(CBL) unascertained measurement(UM) Analysis hierarchy process Information entropy Synthetic weights Comprehensive evaluation
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Optimization model of unascertained measurement for underground mining method selection and its application 被引量:6
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作者 刘爱华 董蕾 董陇军 《Journal of Central South University》 SCIE EI CAS 2010年第4期744-749,共6页
An optimization model of underground mining method selection was established on the basis of the unascertained measurement theory.Considering the geologic conditions,technology,economy and safety production,ten main f... An optimization model of underground mining method selection was established on the basis of the unascertained measurement theory.Considering the geologic conditions,technology,economy and safety production,ten main factors influencing the selection of mining method were taken into account,and the comprehensive evaluation index system of mining method selection was constructed.The unascertained evaluation indices corresponding to the selected factors for the actual situation were solved both qualitatively and quantitatively.New measurement standards were constructed.Then,the unascertained measurement function of each evaluation index was established.The index weights of the factors were calculated by entropy theory,and credible degree recognition criteria were established according to the unascertained measurement theory.The results of mining method evaluation were obtained using the credible degree criteria,thus the best underground mining method was determined.Furthermore,this model was employed for the comprehensive evaluation and selection of the chosen standard mining methods in Xinli Gold Mine in Sanshandao of China.The results show that the relative superiority degrees of mining methods can be calculated using the unascertained measurement optimization model,so the optimal method can be easily determined.Meanwhile,the proposed method can take into account large amount of uncertain information in mining method selection,which can provide an effective way for selecting the optimal underground mining method. 展开更多
关键词 mining engineering underground mining method optimization model unascertained measurement theory information entropy
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Evaluation methods of man-machine-environment system for clean and safe production in phosphorus mines: A case study 被引量:5
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作者 DONG Long-jun ZHOU Ying +2 位作者 DENG Si-jia WANG Mei SUN Dao-yuan 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第12期3856-3870,共15页
Phosphorus is an essential element in agricultural production and chemical industry. However, since the risk of casualties and economic loss by mining accidents, the application of clean and safe production in phospho... Phosphorus is an essential element in agricultural production and chemical industry. However, since the risk of casualties and economic loss by mining accidents, the application of clean and safe production in phosphorus mines encounters great challenges. For this purpose, a man-machine-environment system composed of evaluation indexes was established, and the grading standards of indexes were defined. Firstly, the measurements of 39 qualitative indexes were obtained through the survey data. According to the measured values of 31 quantitative indexes, the measurements of quantitative indexes were calculated by linear measurement function(LM) and other three functions. Then the singleindex measurement evaluation matrixes were established. Secondly, the entropy weight method was used to determine the weights of each index directly. The analytic hierarchy process(AHP) was also applied to calculate the weights of index and index factor hierarchies after the established hierarchical model. The weights of system hierarchies were given by the grid-based fuzzy Borda method(GFB). The comprehensive weights were determined by the combination method of AHP and GFB(CAG). Furthermore, the multi-index comprehensive measurement evaluation vectors were obtained.Thirdly, the vectors were evaluated by the credible degree recognition(CDR) and the maximum membership(TMM)criteria. Based on the above functions, methods, and criteria, 16 combination evaluation methods were recommended.Finally, the clean and safe production grade of Kaiyang phosphate mine in China was evaluated. The results show that the LM-CAG-CDR is the most reasonable method, which can not only determine the clean and safe production grade of phosphorus mines, but also improve the development level of clean and safe mining of phosphorus mines for guidance.In addition, some beneficial suggestions and measures were also proposed to advance the clean and safe production grade of Kaiyang phosphorus mine. 展开更多
关键词 phosphorus mines clean and safe production man-machine-environment system unascertained measurement evaluation grid-based fuzzy borda method analytic hierarchy process
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Measuring Research on County Agricultural Technological Innovation Ability Index 被引量:2
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作者 MA Li-hua YAN Hui-zhe YAN Ping-jian 《Asian Agricultural Research》 2011年第6期16-20,共5页
Taking the mechanism of technological construction guidance theory and mode which consists of "objective-construction-evaluation-construction-objective" as a starting point, on the basis of county agricultur... Taking the mechanism of technological construction guidance theory and mode which consists of "objective-construction-evaluation-construction-objective" as a starting point, on the basis of county agricultural technological innovation ability and its index definition, this paper researches the constructing system of county agricultural technological innovation ability. Firstly, on the basis of defining county agricultural technological innovation ability and the definition of index, according to the principle of purposefulness, scientificity, systematicness, integration of dynamic state and static state, integration of quantitativeness and qualitativeness and so on, we construct the multi-level measuring system of county agricultural technological innovation ability, including 4 first-level indices, namely technological innovation environment, technological innovation basis, technological innovation ability, and technological innovation efficiency; 15 second-level indices, such as technological policy, technological system mechanism, technological institution construction, ability of innovation subject, ability of industrial expansion, scale merit, technological contribution rate. Moreover, this system has 45 third-level indices. Then, by using unascertained mathematics method and AHM method, we establish the multi-level unascertained composite measuring model of county agricultural technological innovation ability index. Finally, by using the survey data of one county in Hebei Province, and the established county agricultural technological innovation ability index model, we get the county agricultural technological innovation ability index of 0.711 by calculation, that is, the innovation ability is at the intermediate level, namely the modern agricultural sub-stage. The empirical research proves the correctness and applicability of this model. 展开更多
关键词 County agriculture Technological innovation ability Index measuring AHM unascertained mathematics China
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Safety assessment of platform loadout procedures based on unascertained measures 被引量:4
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作者 李彦苍 索娟娟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2007年第4期354-358,共5页
Safety assessment of offshore platforms is an urgent task. Such assessments are now focusing on the structure, maintenance, and retirement of a platform. Some methods employed have many shortcomings. For example, they... Safety assessment of offshore platforms is an urgent task. Such assessments are now focusing on the structure, maintenance, and retirement of a platform. Some methods employed have many shortcomings. For example, they cannot make the reliability adequately explicable. Therefore, a mathematical tool, the unascertained measure, was introduced. First, the basic knowledge of the unascertained sets was introduced briefly. Second, the unascertained measure was defined and credible identification was set up. The method has been introduced into the fields for safety assessment of a jacket loadout procedure. Engineering practices showed that it can complete the safety assessment systematically and scientifically without any assumption. The work should have significance in theory and practice for offshore engineering. 展开更多
关键词 safety assessment offshore platform INSTALLATION unascertained measure information entropy
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Assessment of Traffic Safety State of Ship Based on Unascertained Measure
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作者 段爱媛 赵耀 《Journal of Southwest Jiaotong University(English Edition)》 2007年第2期138-141,共4页
Using the theory and method of unascertained measure, an unascertained measure model and the related confidence rule are established to assess the safety state of ship. Thus, the dangerous factors in the hull system c... Using the theory and method of unascertained measure, an unascertained measure model and the related confidence rule are established to assess the safety state of ship. Thus, the dangerous factors in the hull system can be identified, and the accident possibility, loss, and injury degree can be forcasted. An application result shows that the the proposed method is effective in assessment of the traffic safety of ships, and it is more simple in computation than the fuzzy synthetic evaluation method. The proposed method can provide a scientific basis for realizing shipping transportation security and formulating preventive measures. 展开更多
关键词 unascertained measure Traffic safety SHIP ASSESSMENT
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Multi-agent Blind Model and Its Application to Regional Eco-environmental Quality Assessment 被引量:2
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作者 LI Ruzhong 《Chinese Geographical Science》 SCIE CSCD 2006年第3期249-254,共6页
Through denoting each expert as an agent and viewing a multiple criteria decision-making as a synthesis problem of aggregating experts' ratings, a multi-agent blind model (MABM) is developed for regional eco-enviro... Through denoting each expert as an agent and viewing a multiple criteria decision-making as a synthesis problem of aggregating experts' ratings, a multi-agent blind model (MABM) is developed for regional eco-environmental quality assessment. In this model, the ratings of the evaluated object under an index, given by expert group, are first utilized to construct a series of blind numbers. In general, each index will correspond to different blind numbers. On the basis of aggregating index weights, the rank score in the form of a blind number is obtained for the evaluated object. Then, by means of calculating expected value of the above blind number, its rank score is further converted into a crisp value. By way of comparing the expected value with classification standards, eco-environmental quality of the evaluated sample could he identified successfully in the end. As a case, the MABM is used to evaluate the eco-environmental quality of Chaohu Lake basin. Study result shows that the MABM is a useful model for regional eco-environmental quality assessment. 展开更多
关键词 eco-environmental quality assessment multi-agent blind model (MABM) blind number unascertained rational number faith degree
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基于未确知测度的建筑工程质量对工期影响度的确定 被引量:1
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作者 李万庆 周冲 +1 位作者 孟文清 刘历波 《煤炭工程》 北大核心 2007年第1期114-116,共3页
论文建立了基于未确知测度的建筑工程施工质量对施工工期影响度确定模型,并结合工程实例客观准确地确定了建筑工程质量对施工工期的影响度大小。该模型对在处理不确定性影响因素时较模糊数学丢失信息少,运算简便,更实用、可靠。
关键词 施工工期 未确知测度 不确定性 影响度
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An Integrated Multi-Level Early Warning Method for Rainfall-Induced Shallow Landslides 被引量:1
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作者 ZHAO Binbin KONG Xiao'ang +2 位作者 OU Wenhao LIU Yi YANG Zhi 《Earthquake Research in China》 CSCD 2020年第1期136-156,共21页
Rainfall-induced landslides have occurred frequently in Southwestern China since the Wenchuan earthquake,resulting in massive loss of people’s life and property.Fortunately,landslide early-warning is one of the most ... Rainfall-induced landslides have occurred frequently in Southwestern China since the Wenchuan earthquake,resulting in massive loss of people’s life and property.Fortunately,landslide early-warning is one of the most important tools for landslide hazard prevention and mitigation.However,the accumulation of historical data of the landslides induced by rainfall is limited in many remote mountain areas and the stability of the slope is easily affected by human engineering activities and environmental changes,leading to difficulties to accurately realize early warning of landslide hazards by statistical methods.The proposed warning method is divided into rainfall warning component and deformation warning component because the deformation induced by rainfall has the characteristic of hysteretic nature.Rainfall,tilted angle and crack width are chosen as monitoring indexes.Rainfall grade level that contains rainfall intensity and duration information is graded according to the variation of the safety factor calculated by 3-D finite difference numerical simulation method,and then is applied using the strength reduction method and unascertained information theory to obtain the deformation grade level of several monitored points.Finally,based on the system reliability theory,we establish a comprehensive landslide warning level method that provides four early warning levels to reflect the safety factor reductions during and post rainfall events.The application of this method at a landslide site yield generally satisfactory results and provide a new method for performing multi-index and multi-level landslide early warnings. 展开更多
关键词 LANDSLIDES EARLY WARNING RAINFALL Deformation unascertained DEGREE theory
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The Unascertained Comprehensive Evaluation on Rationalization of Regional Industrial Structure 被引量:1
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作者 Xiaoguo Ma Fengqiu Du Kaidi Liu 《Journal of Systems Science and Information》 2006年第3期609-620,共12页
The index system of regional industrial structure is set up. There are two delaminated levels, the top layer evaluation and the bottom one on which the top evaluation is based. That is the characteristics of the evalu... The index system of regional industrial structure is set up. There are two delaminated levels, the top layer evaluation and the bottom one on which the top evaluation is based. That is the characteristics of the evaluation of regional industry structure. The distinction between the two evaluation levels involves the two essentially different two index weights, the unsscertalned comprehensive evaluating model together with division weight are used in the bottom evaluation, and expert weight in the top layer evaluation. In view of the evaluation of regional industrial structure, a sort of comparatively reasonable utility evaluation model is set up. Take the case of Beijing and other six provinces and cities is positively analyzed, which reflects the actual regional industrial structure. 展开更多
关键词 regional industrial structure index system unascertained comprehensive evaluation division weight expert weight
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混凝土抗渗性能预测的未确知判别分析模型
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作者 万正义 《混凝土》 CAS CSCD 北大核心 2011年第7期39-40,52,共3页
混凝土抗渗性直接影响着混凝土的耐久性,为解决传统试验方法耗费大量时间的不足,提出用未确知判别分析模型对多种配合比的混凝土进行渗透性仿真计算。该研究成果可以减少混凝土试配次数,节约大量的人力、物力和时间,为高性能混凝土的研... 混凝土抗渗性直接影响着混凝土的耐久性,为解决传统试验方法耗费大量时间的不足,提出用未确知判别分析模型对多种配合比的混凝土进行渗透性仿真计算。该研究成果可以减少混凝土试配次数,节约大量的人力、物力和时间,为高性能混凝土的研究发展奠定了基础。结果表明此模型的可靠度很高,可以用于混凝土渗透性的设计及评估。实例分析表明,建立的未确知判别分析模型预测精度高,为混凝土抗渗性能预测提供一条新途径。 展开更多
关键词 混凝土 抗渗性 未确知 判别分析
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Appraisal on the Regional Technological Innovation Ability Based on Unascertained Measure Method
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作者 Qingkui Cao Xiangyang Ren Yanli Yang 《Journal of Systems Science and Information》 2006年第3期477-484,共8页
In market economics, the regional technological innovation ability has become an important factor in the sustainable development of this region and important position in the region's competition. In this paper, the a... In market economics, the regional technological innovation ability has become an important factor in the sustainable development of this region and important position in the region's competition. In this paper, the application of unascertained measure method in the ability of the regional technological innovation is studied. The appraisal index system is setup and the unascertained measure model is given . At last, an example is given to verify the theory model. 展开更多
关键词 index system information entropy technological innovation ability unascertained measure
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未确知数学法在蚀变岩密集带综合变形模量取值中的应用
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作者 赵梓彤 沈军辉 +2 位作者 徐鹏 祝华平 魏伟 《成都理工大学学报(自然科学版)》 CAS CSCD 北大核心 2016年第3期372-377,共6页
针对雅砻江孟底沟水电站坝基中蚀变岩密集带岩体综合变形模量取值的不确定性,采用一种不确定信息的处理方法——未确知数学法来计算其综合变形模量。以典型蚀变岩密集带为例,计算结果表明其综合变形模量取值在17~18 GPa时,可信度最大,... 针对雅砻江孟底沟水电站坝基中蚀变岩密集带岩体综合变形模量取值的不确定性,采用一种不确定信息的处理方法——未确知数学法来计算其综合变形模量。以典型蚀变岩密集带为例,计算结果表明其综合变形模量取值在17~18 GPa时,可信度最大,保证率为83.80%。相比非线性回归法及算术平均法等传统方法的计算值为19.40GPa、保证率仅为61.36%而言,未确知数学法的计算结果更为合理、可靠。 展开更多
关键词 蚀变岩 变形模量 未确知性 保证率
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基于未确知测度的建筑工程工期影响度分析
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作者 赵丽 朱建亚 李群 《山西建筑》 2008年第4期227-228,共2页
给出未确知测度、置信度的概念,建立了基于未确知测度的建筑工程施工资源对施工工期影响度确定模型,指出该模型在处理不确定性影响因素时丢失信息少,更实用、可靠,最后给出了工程实例加以验证。
关键词 施工工期 未确知测度 不确定性 影响度
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Information fusion based on addition of unascertained rational numbers for recognization of spatial point targets
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作者 张池平 宋向勃 崔祜涛 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第3期332-334,共3页
A new uncertain information model, i.e. unascertainment, which is different from randomness,fuzziness and grayness, has been introduced into information fusion to give a reasoning method,which is basedon addition of u... A new uncertain information model, i.e. unascertainment, which is different from randomness,fuzziness and grayness, has been introduced into information fusion to give a reasoning method,which is basedon addition of unascertained rational number and can be used to recognize spatial point targets. The validity ofthe method proposed is verified through an example. 展开更多
关键词 unascertained information information fusion
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