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七套模拟电视关模——用不同的方式解决问题
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作者 李波 《有线电视技术》 2018年第9期112-113,共2页
本文介绍了一种非常规的关模方法,节省了大量的成本和人力资源,大大提升了关模效率,以期为同行提供一定的经验和借鉴。
关键词 关模 干扰 方案
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有线数字电视整转后分区域关模的实施方式
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作者 孙国超 鞠国山 《中国数字电视》 2011年第12期58-61,共4页
如何提高整转率,降低关模工作带来的影响,是有线电视数字化要面对的重要问题。本文结合扬州市城区关模的实践,重点介绍了扬州分区域、分批次关模的实施方案。
关键词 数字电视整转 关模 模数混传 电平调整
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A Hybrid Compensation Scheme for the Input Rate-Dependent Hysteresis of the Piezoelectric Ceramic Actuators
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作者 DONG Ruili TAN Yonghong +1 位作者 HOU Jiajia ZHENG Bangsheng 《Journal of Donghua University(English Edition)》 CAS 2024年第4期436-446,共11页
A hybrid compensation scheme for piezoelectric ceramic actuators(PEAs)is proposed.In the hybrid compensation scheme,the input rate-dependent hysteresis characteristics of the PEAs are compensated.The feedforward contr... A hybrid compensation scheme for piezoelectric ceramic actuators(PEAs)is proposed.In the hybrid compensation scheme,the input rate-dependent hysteresis characteristics of the PEAs are compensated.The feedforward controller is a novel input rate-dependent neural network hysteresis inverse model,while the feedback controller is a proportion integration differentiation(PID)controller.In the proposed inverse model,an input ratedependent auxiliary inverse operator(RAIO)and output of the hysteresis construct the expanded input space(EIS)of the inverse model which transforms the hysteresis inverse with multi-valued mapping into single-valued mapping,and the wiping-out,rate-dependent and continuous properties of the RAIO are analyzed in theories.Based on the EIS method,a hysteresis neural network inverse model,namely the dynamic back propagation neural network(DBPNN)model,is established.Moreover,a hybrid compensation scheme for the PEAs is designed to compensate for the hysteresis.Finally,the proposed method,the conventional PID controller and the hybrid controller with the modified input rate-dependent Prandtl-Ishlinskii(MRPI)model are all applied in the experimental platform.Experimental results show that the proposed method has obvious superiorities in the performance of the system. 展开更多
关键词 hybrid control input rate-dependent hysteresis inverse model neural network piezoelectric ceramic actuator
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Implicative and Fuzzy Implicative Ideals of Lattice Implication Algebras 被引量:11
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作者 赵光峰 徐扬 宋振明 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第4期104-110,共7页
In this paper, we defined the concept of implicative and fuzzy implicative ideals of lattice implication algebras, and discussed the properties of them. And then, we pointed out the relations between implicative ideal... In this paper, we defined the concept of implicative and fuzzy implicative ideals of lattice implication algebras, and discussed the properties of them. And then, we pointed out the relations between implicative ideal and LI _ideal, implicative iedal and implicative filter, implicative ideal and fuzzy implicative ideal, fuzzy implicative ideal and fuzzy implicative filter, and fuzzy implicative ideal and fuzzy LI _ideal. 展开更多
关键词 lattice implication algebra fuzzy LI _ideal fuzzy filter implicative ideal fuzzy implicative ideal
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A New Role Hierarchy Model for Role Based Access Control 被引量:2
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作者 吕宜洪 宋瀚涛 龚元明 《Journal of Beijing Institute of Technology》 EI CAS 2002年第4期409-413,共5页
A new role hierarchy model for RBAC (role-based access control) is presented and its features are illustrated through examples. Some new concepts such as private permission, public permission and special permission ar... A new role hierarchy model for RBAC (role-based access control) is presented and its features are illustrated through examples. Some new concepts such as private permission, public permission and special permission are introduced, based on the RRA97 model. Some new role-role inheriting forms such as normal inheritance, private inheritance, public inheritance and special-without inheritance are defined. Based on the ideas mentioned, the new role hierarchy model is formulated. It is easier and more comprehensible to describe role-role relationships through the new model than through the traditional ones. The new model is closer to the real world and its mechanism is more powerful. Particularly it is more suitable when used in large-scale role hierarchies. 展开更多
关键词 RBAC access control ROLE INHERIT role hierarchy
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Reservoir detection based on EMD and correlation dimension 被引量:3
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作者 文晓涛 贺振华 黄德济 《Applied Geophysics》 SCIE CSCD 2009年第1期70-76,103,104,共9页
In hydrocarbon reservoirs, seismic waveforms become complex and the correlation dimension becomes smaller. Seismic waves are signals with a definite frequency bandwidth and the waveform is affected by all the frequenc... In hydrocarbon reservoirs, seismic waveforms become complex and the correlation dimension becomes smaller. Seismic waves are signals with a definite frequency bandwidth and the waveform is affected by all the frequency components in the band. The results will not define the reservoir well if we calculate correlation dimension directly. In this paper, we present a method that integrates empirical mode decomposition (EMD) and correlation dimension. EMD is used to decompose the seismic waves and calculate the correlation dimension of every intrinsic mode function (IMF) component of the decomposed wave. Comparing the results with reservoirs identified by known wells, the most effective IMF is chosen and used to predict the reservoir. The method is applied in the Triassic Zhongyou group in the XX area of the Tahe oil field with quite good results. 展开更多
关键词 empirical mode decomposition correlation dimension intrinsic mode function RESERVOIR
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Multiplexer Design Applied to High-Speed Signal Transmission 被引量:2
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作者 曹寒梅 杨银堂 +2 位作者 蔡伟 陆铁军 王宗民 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1040-1043,共4页
A multiplexer with a low-distortion high-bandwidth analog switch is presented. The gate-to-source voltage of the switch is set by the combined on-voltage of a pMOS and an nMOS,and the difference between its gate-sourc... A multiplexer with a low-distortion high-bandwidth analog switch is presented. The gate-to-source voltage of the switch is set by the combined on-voltage of a pMOS and an nMOS,and the difference between its gate-source voltage and the threshold voltage (VGST) is guaranteed to be constant with input variation. Thus, the body effect is nearly canceled. Implemented in a TSMC 0.18μm CMOS process, results from HSPICE simulation show that the VGST is nearly constant with an input range from 0.3 to 1.7V,and the - 3dB bandwidth is larger than 10GHz;the SFDR (spurious free dynamic range) of the output is 67. lldB with 1GHz input frequency; the turn-on time is 2.98ns,and the turn-off time is 1.35ns, which indicates a break-before-make action of the multiplexer. The proposed structure can be applied to high speed signal transmission. 展开更多
关键词 low-distortion high speed MULTIPLEXER analog switch
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Yield Modeling of Rectangular Defect Outline 被引量:1
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作者 王俊平 郝跃 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第8期1514-1518,共5页
In integrated circuits, the defects associated with photolithography are assumed to be in the shape of circular discs in order to perform the estimation of yield and fault analysis. However,real defects exhibit a grea... In integrated circuits, the defects associated with photolithography are assumed to be in the shape of circular discs in order to perform the estimation of yield and fault analysis. However,real defects exhibit a great variety of shapes. In this paper,a novel yield model is presented and the critical area model of short circuit is correspondingly provided. In comparison with the circular model corrently available, the new model takes the similarity shape to an original defect, the two-dimensional distributional characteristic of defects, the feature of a layout routing and the character of yield estimation into account. As for the aspect of prediction of yield, the experimental results show that the new model may predict the yield caused by real defects more accurately than the circular model does. It is significant that the yield is accurately estimated and improved using the proposed model. 展开更多
关键词 real defect rectangular defect model critical area yield modeling
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Use of the pilodyn for assessing wood properties in standing trees of Eucalyptus clones 被引量:3
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作者 吴世军 徐建民 +4 位作者 李光友 RISTO Vuokko 陆钊华 李宝琦 王伟 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第1期68-72,I0003,共6页
The effectiveness of pilodyn was tested in evaluating wood basic density, outer wood density, heartwood density, and modulus of elasticity (MoE) at 22 four-year-old eucalyptus clones in Guangxi, China. Results indic... The effectiveness of pilodyn was tested in evaluating wood basic density, outer wood density, heartwood density, and modulus of elasticity (MoE) at 22 four-year-old eucalyptus clones in Guangxi, China. Results indicated that the mean value ranged from 9.44 to 15.41 mm for Pilodyn penetration, 0.3514 to 0.4913 g.cm^-3 for wood basic density, and 3.94 to 7.53 Giga Pascal (GPa) for MoE, respectively. There were significant differences (1% level) in pilodyn penetration between different treatments, different directions and among the clones. Generally strongly negative correlations were found between pilodyn penetration and wood properties, and the coefficients ranged from -0,433 to -0,755. Our results, together with other studies, suggest that the use of pilodyn for assessing wood density and MoE was confirmed as a possibility. 展开更多
关键词 CORRELATION EUCALYPTUS modulus of elasticity PILODYN wood density
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Change Trend of Chinese Urban Residents' Food-nitrogen Consumption 被引量:2
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作者 王俊能 许振成 彭晓春 《Agricultural Science & Technology》 CAS 2010年第4期176-179,共4页
Change trend of Chinese urban residents' per capita food-nitrogen annual consumption from 1981 to 2007 was analyzed and predicted by using ARIMA time-series model in order to reveal the change of urban food-nitrogen ... Change trend of Chinese urban residents' per capita food-nitrogen annual consumption from 1981 to 2007 was analyzed and predicted by using ARIMA time-series model in order to reveal the change of urban food-nitrogen consumption during the China's urbanization process.Results showed that after 1980s,the annual consumption of Chinese urban residents' food-nitrogen had a change trend of " increase-decrease-increase" and generally presented as a slight increasing trend;With the acceleration of rapid economic development and urbanization process,Chinese urban residents' food-nitrogen consumption will still keep a rising trend in future,and also has a large rising space. 展开更多
关键词 Food consumption NITROGEN Spearman's rank correlation coefficient ARIMA model Urban residents China
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Analysis of Driving Factors of Grain Output in Henan Province Based on Grey Correlation Model 被引量:1
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作者 贺振 《Agricultural Science & Technology》 CAS 2009年第3期123-126,147,共5页
Henan Province is an important grain production base, whose stable production is related to the economic development and social stability significantly. To summarize the primary factors of grain producing, we used gre... Henan Province is an important grain production base, whose stable production is related to the economic development and social stability significantly. To summarize the primary factors of grain producing, we used grey correlation analysis method to analyze 10 correlative factors such as grain yield, grain yield per unit area, effective irrigated area, rural employed persons, grain planting area, consumption of chemical fertilizer in 25 years. The results showed order of synthetic degree of incidence: effective irrigated area>rural electricity consumption>consumption of chemical fertilizer>disaster crop area>grain yield per unit of area>total power of agricultural machinery>afflicted crop area>grain planting area>number of the rural employed persons. Finally, according to synthetic degree of incidence between influential factors and total grain output respectively, a series of measures and the suggestions was proposed for grain production in Henan Province, which will also provide the scientific basis and help for the government correct decision-making. 展开更多
关键词 Grain yield Grey correlation analysis Driving force Henan Province
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Text categorization based on fuzzy classification rules tree 被引量:2
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作者 郭玉琴 袁方 刘海博 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期339-342,共4页
To deal with the problem that arises when the conventional fuzzy class-association method applies repetitive scans of the classifier to classify new texts,which has low efficiency, a new approach based on the FCR-tree... To deal with the problem that arises when the conventional fuzzy class-association method applies repetitive scans of the classifier to classify new texts,which has low efficiency, a new approach based on the FCR-tree(fuzzy classification rules tree)for text categorization is proposed.The compactness of the FCR-tree saves significant space in storing a large set of rules when there are many repeated words in the rules.In comparison with classification rules,the fuzzy classification rules contain not only words,but also the fuzzy sets corresponding to the frequencies of words appearing in texts.Therefore,the construction of an FCR-tree and its structure are different from a CR-tree.To debase the difficulty of FCR-tree construction and rules retrieval,more k-FCR-trees are built.When classifying a new text,it is not necessary to search the paths of the sub-trees led by those words not appearing in this text,thus reducing the number of traveling rules.Experimental results show that the proposed approach obviously outperforms the conventional method in efficiency. 展开更多
关键词 text categorization fuzzy classification association rule classification rules tree fuzzy classification rules tree
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超50°坡屋面主体结构施工技术研究 被引量:3
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作者 肖维 罗兴 +2 位作者 黄镜维 冷冬 陈海 《工程技术研究》 2021年第14期84-85,共2页
屋面工程是施工过程中的重点和难点,超50°坡屋面工程更是屋面工程施工的难点,因此坡屋面采取的施工方案及技术措施尤为关键。文章结合帝谷·公园城三期施工案例坡屋面主体结构施工采取双面关模+自密实混凝土施工方法,对超过50&... 屋面工程是施工过程中的重点和难点,超50°坡屋面工程更是屋面工程施工的难点,因此坡屋面采取的施工方案及技术措施尤为关键。文章结合帝谷·公园城三期施工案例坡屋面主体结构施工采取双面关模+自密实混凝土施工方法,对超过50°坡屋面主体结构施工的工艺流程及施工要点进行阐述,保证了坡屋面混凝土振捣密实、成型质量美观、屋面不渗漏,为类似坡屋面施工提供了参考。 展开更多
关键词 坡屋面施工 主体结构 双面关模 自密实混凝土
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Priority approach based on quadratic programming model to fuzzy preference relation 被引量:1
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作者 徐泽水 达庆利 陈琦 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期108-110,共3页
We investigate the decision-making problem with a finite set of alternatives,in which the decision information takes the form of a fuzzy preference relation. We develop asimple and practical approach to obtaining the ... We investigate the decision-making problem with a finite set of alternatives,in which the decision information takes the form of a fuzzy preference relation. We develop asimple and practical approach to obtaining the priority vector of a fuzzy preference relation. Theprominent characteristic of the developed approach is that the priority vector can generally beobtained by a simple formula, which is derived from a quadratic programming model. We utilize theconsistency ratio to check the consistency of fuzzy preference relation. If the fuzzy preferencerelation is of unacceptable consistency, then we can return it to the decision maker to reconsiderstructuring a new fuzzy preference relation until the fuzzy preference relation with acceptableconsistency is obtained. We finally illustrate the priority approach by two numerical examples. Thenumerical results show that the developed approach is straightforward, effective, and can easily beperformed on a computer. 展开更多
关键词 decision making fuzzy preference relation quadratic programming PRIORITY
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Business domain oriented AI planning for web service composition
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作者 代钰 杨雷 张斌 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期421-424,共4页
In order to improve the effectiveness of the artificial intelligence (AI) planning based web service composition problem, a business domain oriented AI planning algorithm for web service composition is introduced. T... In order to improve the effectiveness of the artificial intelligence (AI) planning based web service composition problem, a business domain oriented AI planning algorithm for web service composition is introduced. The algorithm uses the proposed business relation model to minimize the searching space and uses the proposed goal distance as a heuristic rule. Compared with other algorithms tackling web service composition such as AI planning, the proposed algorithm focuses not only on how to convert the web service composition problem to the AI planning problem, but also exerts its effort on how to apply the business feature of web service composition into planning in order to improve the effectiveness. The experiment shows the better performance of the proposed algorithm. 展开更多
关键词 AI planning web service web service composition business relation model
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Optically Activated Charge Domain Model for High-Gain GaAs Photoconductive Switches 被引量:3
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作者 施卫 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第12期1481-1485,共5页
A model for theoretical analysis of nonlinear (or high gain) mode of photoconductive semiconductor switches (PCSS's) is proposed.The switching transition of high gain PCSS's can be described with an optically... A model for theoretical analysis of nonlinear (or high gain) mode of photoconductive semiconductor switches (PCSS's) is proposed.The switching transition of high gain PCSS's can be described with an optically activated charge domain. The switching characteristics including rise time,delay and their relationship to electric field strength,optical trigger energies are discussed.The formation and radiation transit,accumulation of the charge domain are related with the triggering and sustaining phases of PCSS's,respectively.The results of the mathematical model on this mechanism agree with experimental results. 展开更多
关键词 photoconductive switches high gain mode optically activated charge domain
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COUPLING MODEL OF EXTENDED MANUFACTURING ORGANIZATION AND ITS APPLICATION 被引量:1
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作者 郭宇 安波 廖文和 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第1期137-144,共8页
For the feature of complex weapon manufacturing on internet,a coupling model is proposed.By using the model,the correlation between manufacturing cells in an extended manufacturing organization can be evaluated quanti... For the feature of complex weapon manufacturing on internet,a coupling model is proposed.By using the model,the correlation between manufacturing cells in an extended manufacturing organization can be evaluated quantitatively,so an appropriate control plan is determined.A strategy to improve and reduce the coupling relationship of the organization is studied.A correlation matrix of extended tasks is built to analyze the relationship between sub-tasks and manufacturing resources.An optimization method for manufacturing resource configuration is presented based on the coupling model.Finally,a software system for analyzing coupling model about manufacturing organization on internet is developed,and the result shows that the coupling model is effective. 展开更多
关键词 networked manufacturing manufacturing organization correlation matrix coupling model
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ESTIMATION METHOD FOR AIRCRAFT SIMILARITY BASED ON FUZZY THEORY AND GREY INCIDENCE ANALYSIS 被引量:4
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作者 李永平 陈闵叶 刘明 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第3期194-198,共5页
An estimation method for aircraft similarity based on fuzzy theory and grey incidence analysis is presented. This estimation method is made up of the triangular fuzzy transforming model of linguistic variables and the... An estimation method for aircraft similarity based on fuzzy theory and grey incidence analysis is presented. This estimation method is made up of the triangular fuzzy transforming model of linguistic variables and the method of grey incidence analysis. Nine feature attributes of aircraft are selected to estimate the similarity between the new aircraft and the existing aircraft. A new aircraft X and other six existing aircrafts are taken as examples. Analyses show that similarity estimation results obtained from the method are in accordance with practice. 展开更多
关键词 aircraft similarity fuzzy theory grey incidence analysis
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Application Comparison of Association Rules and C4.5 Rules in Land Evaluation 被引量:3
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作者 李亭 杨敬锋 陈志民 《Agricultural Science & Technology》 CAS 2010年第4期144-147,共4页
Association rules and C4.5 rules can overcome the shortage of the traditional land evaluation methods and improve the intelligibility and efficiency of the land evaluation knowledge.In order to compare these two kinds... Association rules and C4.5 rules can overcome the shortage of the traditional land evaluation methods and improve the intelligibility and efficiency of the land evaluation knowledge.In order to compare these two kinds of classification rules in the application,two fuzzy classifiers were established by combining with fuzzy decision algorithm especially based on Second General Soil Survey of Guangdong Province.The results of experiments demonstrated that the fuzzy classifier based on association rules obtain a higher accuracy rate,but with more complex calculation process and more computational overhead;the fuzzy classifier based on C4.5 rules obtain a slightly lower accuracy,but with fast computation and simpler calculation. 展开更多
关键词 Land evaluation Association rules C4.5 Algorithm Fuzzy decision
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有线电视网络搭建“关闭模拟电视”平台的技术方案
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作者 汪锐 李必虎 《中国有线电视》 2012年第3期264-266,共3页
通过对有线电视网络关闭模拟电视(简称"关模")技术方案的案例分析,为各地在推进有线电视数字化整转过程中,搭建"关模"平台技术方案的选择提供参考。
关键词 有线数字电视 数字电视整转 关模平台
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