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从《文心雕龙·丽辞》的分类看丽辞的能指性 被引量:1
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作者 蔡莹 《韶关学院学报》 2008年第4期20-23,共4页
《文心雕龙·丽辞》在丽辞的产生、丽辞使用的语言材料、丽辞的互文特色、丽辞激发的审美联想等多方面体现了鲜明的能指性。
关键词 《文心雕龙》 丽辞 能指性
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汉字六书象形构形法
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作者 张泽渡 《大观周刊》 2011年第29期4-5,共2页
研究汉字构形理论“六书”的典籍汗牛充栋,其中象形字的研究相对比较成熟充分,但学界仍有省形、变形、增形、重形、附形等诸多歧说。各种解说或名同实异、或名异实同,互相交叉的各家学说使人对六书学理论产生疑惑。我们从说明象形字... 研究汉字构形理论“六书”的典籍汗牛充栋,其中象形字的研究相对比较成熟充分,但学界仍有省形、变形、增形、重形、附形等诸多歧说。各种解说或名同实异、或名异实同,互相交叉的各家学说使人对六书学理论产生疑惑。我们从说明象形字的构形原理出发,指出六书系统中的象形字具有具象构形与意象构形的区别。具象构形仅仅能满足“陈述”,意象构形才能实现“表达”。从分析汉字的语言性质和文化意义着眼,以联体象形的概念取代省、变、增、重、附的多种杂说,才能确认汉字象形构形法的实践价值和理论意义。 展开更多
关键词 心理赋形 形符固化 具象构形 意象构形 联体象形 所指 能指性
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汉字六书象形构形法
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作者 张泽渡 《大观周刊》 2011年第31期5-6,共2页
研究汉字构形理论“六书”的典籍汗牛充栋,其中象形字的研究相对比较成熟充分,但学界仍有省形、变形、增形、重形、附形等诸多歧说。各种解说或名同实异、或名异实同,互相交叉的各家学说使人对六书学理论产生疑惑。我们从说明象形字... 研究汉字构形理论“六书”的典籍汗牛充栋,其中象形字的研究相对比较成熟充分,但学界仍有省形、变形、增形、重形、附形等诸多歧说。各种解说或名同实异、或名异实同,互相交叉的各家学说使人对六书学理论产生疑惑。我们从说明象形字的构形原理出发,指出六书系统中的象形字具有具象构形与意象构形的区别。具象构形仅仅能满足“陈述”,意象构形才能实现“表达”。从分析汉字的语言性质和文化意义着眼,以联体象形的概念取代省、变、增、重、附的多种杂说,才能确认汉字象形构形法的实践价值和理论意义。 展开更多
关键词 心理赋形 形符固化 具象构形 意象构形 联体象形 所指 能指性
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Effects of Milk Replacer on the Performance and Blood Biochemical Indices in Lambs 被引量:13
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作者 郭爱伟 张力 +2 位作者 熊春梅 周学辉 苗小林 《Agricultural Science & Technology》 CAS 2008年第1期107-110,共4页
[Objective] In this study, the performance and blood biochemical indices in lamps fed on milk replacer were researched, the feasibility of early weaned in lamps was discussed. [Method] 37 of 10 days lambs of Suffolk... [Objective] In this study, the performance and blood biochemical indices in lamps fed on milk replacer were researched, the feasibility of early weaned in lamps was discussed. [Method] 37 of 10 days lambs of Suffolk(♂) x XiaoWeiHanYang( ♀ ) were randomly divided into group A, B, C, D for this experiment. Group A, B, C were fed by 3 milk-replacers containing milk for different protein source respectively, and ten Iambs in each group; group D (seven lambs) were fed by ewes as the control. The performance and blood biochemical indices of the lamps were determined. [ Result] The results showed that the average daily gains of 10 - 15 days of age was not significantly different between group A and D ( P 〉 O. 05 ), the control were higher significandy than the group B,C (P 〈0.05). The average daily gains of 16 -25, 26 -35 days of age were not significantly different in group A, B, C, D. The daily weight gains of Group A, B, C in 45 - 55 days of age were higher significantly than the control (P〈0.05 ). Plasma urea nitrogen (PUN) of group B and C were higher than group A significantly (P〈0.05 ) ;Total protein ( TP), Plasma albumin (ALB) and Plasma total amino acid were no significant difference among the other 3 groups (P〉0.05 ). [Conclusion] So, the milk-replacers were available for early-weaned lamb. 展开更多
关键词 Early-weaned lamb Milk replacer PERFORMANCE Blood biochemical indices
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Effects of Different Padding on Air Quality in Broiler House and Growth Physiological Index of Broilers 被引量:1
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作者 刘雪兰 张燕 +5 位作者 阎佩佩 井庆川 魏祥法 刘瑞亭 石天虹 武彬 《Agricultural Science & Technology》 CAS 2015年第12期2764-2769,共6页
[Objective] This study aimed to investigate the effects of different padding on ammonia concentration in broiler house and growth performance and blood indi- cators of broilers. [Method] A total of 480 one-day-old 817... [Objective] This study aimed to investigate the effects of different padding on ammonia concentration in broiler house and growth performance and blood indi- cators of broilers. [Method] A total of 480 one-day-old 817 broilers were selected. They were randomly divided into four groups with different paddings, and each group was in triplicate. The weights of broilers and feed were weighed weekly. The growth performance of broilers was determined. On day 30, the ammonia concentra- tions in broiler houses were determined. On day 35, 6 broilers were randomly se- lected from each group, and their vein blood was sampled. In the sampled vein blood, the concentrations of ammonia, glucose, globulin, serum total protein and urea nitrogen were determined. [Result] There were significant differences in ammo- nia concentration among broiler houses laid with different paddings (P〈0.05). The ammonia concentration in group 1 was significantly lower than those in group 3 and group 4 (P〈0.05). No significant difference was found in ammonia concentrations in broiler houses between group 2 and group 3 (P〉0.05). The ammonia concentration in group 4 was significantly higher than those in group1, group 2 and group 3 (,0〈 0.05). There were also significant differences in blood indicators among different groups (P〈0.05). The blood ammonia, blood glucose and serum urea nitrogen con- centrations in group 1 were significantly lower than those in other groups (P〈0.05), the serum total protein concentration was significantly higher than those in group 3 and group 4 (P〈0.05), and the serum globulin concentration was significantly higher than those in group 2, group 3 and group 4 (P〈0.05). Significant differences were observed in feed intake, body weight gain and slaughter weight between different groups (P〈0.05), but there were no significant differences in feed to grain ratio (P〉 0.05). [Conclusion] Under the experimental conditions, the padding of Chinese medicine residue showed better effect on reducing ammonia concentration in broiler house, which was conducive to play of production potential of broilers. 展开更多
关键词 Chinese medicine residue PADDING Ammonia concentration Production performance Blood indicators
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Effects of Probiotics on Growth Performance and Blood Biochemical Indexes of Cherry Valley Ducks 被引量:4
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作者 李小芬 杨晓志 +3 位作者 陶勇 张玲 顾文婕 袁旭红 《Agricultural Science & Technology》 CAS 2015年第8期1732-1734,1740,共4页
In order to investigate the effects of probiotics on growth performance, blood biochemical indexes and economic benefits of Cherry Valley ducks, different probiotics were added into the feed of Cherry Valley ducks. To... In order to investigate the effects of probiotics on growth performance, blood biochemical indexes and economic benefits of Cherry Valley ducks, different probiotics were added into the feed of Cherry Valley ducks. Total 240 1-d-old Cherry Valley ducks were selected, and they were randomly divided into 4 groups, including 1 control group and 3 treatment groups. There were 3 replicates for each group and there were 20 ducks for each replicate. The ducks in the control group were fed the basal diet, and the ducks in the 3 treatment groups were fed the basal diet added with Lactobacillus, Bacillus natto and florfenicol, respectively. The test lasted for 42 d. The results showed that the addition of Lactobacillus and Bacillus natto could improve the average daily weight gain and final average weight (P〈0.05) of Cherry Valley ducks, and reduce the glutamic-pyruvic transaminase ac- tivity, alkaline phosphatase activity and serum urinary nitrogen content in duck blood (P〈0.05) and reduce the creatinine content and total cholesterol content in Cherry Valley ducks (P〉0.05); at the same time, adding probiotics to feed could also in- crease the grass economic benefits of Cherry Valley ducks. In overall, the effects of adding probiotics were better than those of adding antibiotic. 展开更多
关键词 Cherry Valley duck Probiotic Growth performance Blood biochemicalindex Economic benefits
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Methods of Validating Simulation Model and Program Design
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作者 陈利 张庆明 +1 位作者 王晓英 汪于力 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期125-128,共4页
Validating simulation model is one of the important aspects for modeling and simulation. Some methods of validating model are compared and analyzed. Several typical methods, such as TIC’s inequality coefficient, gray... Validating simulation model is one of the important aspects for modeling and simulation. Some methods of validating model are compared and analyzed. Several typical methods, such as TIC’s inequality coefficient, gray interconnected analysis, direct spectrum estimation, maximum entropy spectral estimation based on Burg or Marple, are chosen and programmed in C language. Some examples by using the program are given. The results show that the program is available and it is best to adopt multi methods for validating models. 展开更多
关键词 VALIDATION simulation model interconnected analysis frequency spectrum estimation
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Analysis on the Functions and Properties of the Preliminarily Determined Characteristics Listed in DUS Test Guideline of Tagetes L.
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作者 刘艳芳 张建华 +5 位作者 杨晓洪 张惠 陈海荣 徐云 管俊娇 王江民 《Agricultural Science & Technology》 CAS 2012年第8期1789-1792,共4页
[Objective] This study aimed to investigate the functions and properties of the preliminarily determined characteristics listed in DUS test guideline of Tagetes L., and explore the representativeness and comprehensive... [Objective] This study aimed to investigate the functions and properties of the preliminarily determined characteristics listed in DUS test guideline of Tagetes L., and explore the representativeness and comprehensiveness of this group of characteristics in DUS test. [Method] Based on the functions and properties of the characteristics, the described plant part (s), observation stage, expression pattern and observation method of each characteristic were analyzed to illustrate the representativeness and comprehensiveness of the combination of this group of characteristics in above functions and properties. [Result] As for described plant part(s), there are 5 characteristics describing plant as a whole, 3 characteristics describing stem, 6 characteristics describing leaf, 23 characteristics describing flower and 1 characteristic describing physiological feature. As for observation stage, there are 1 characteristic needing to be observed in the stage of seedling, 1 characteristic in the stage of beginning of flowering and other 36 characteristics in the stage of fully flowering. As for the expression pattern, there are 10 qualitative characteristics, 9 pseudo-qualitative characteristics and 19 quantitative characteristics. As for the observation method, there are 30 characteristics using VG as the observation method, and 8 characteristics using MS. [Conclusion] In view of the variation and morphological properties of marigold, this group of characteristics are representative and comprehensive, and ensure the accuracy and easiness of DUS test of Tagetes L., thereby achieving the reasonable combination of characteristics in described plant parts, observation stages, expression patterns and observation methods. 展开更多
关键词 DUS test guideline of Tagetes L. CHARACTERISTIC Function PROPERTY
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Full tensor gravity gradiometry data inversion:Performance analysis of parallel computing algorithms 被引量:2
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作者 侯振隆 魏晓辉 +1 位作者 黄大年 孙煦 《Applied Geophysics》 SCIE CSCD 2015年第3期292-302,465,共12页
We apply reweighted inversion focusing to full tensor gravity gradiometry data using message-passing interface (MPI) and compute unified device architecture (CUDA) parallel computing algorithms, and then combine M... We apply reweighted inversion focusing to full tensor gravity gradiometry data using message-passing interface (MPI) and compute unified device architecture (CUDA) parallel computing algorithms, and then combine MPI with CUDA to formulate a hybrid algorithm. Parallel computing performance metrics are introduced to analyze and compare the performance of the algorithms. We summarize the rules for the performance evaluation of parallel algorithms. We use model and real data from the Vinton salt dome to test the algorithms. We find good match between model efficiency and feasibility of parallel computing gravity gradiometry data. and real density data, and verify the high algorithms in the inversion of full tensor 展开更多
关键词 MPI CUDA performance metrics full tensor gravity gradiometry density inversion
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Relationship between Living Rate of Bud and Emergence Rate of Ratoon Rice and Characteristics of the First Cropping Mid-season Hybrid Rice
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作者 张林 熊洪 +4 位作者 徐富贤 朱永川 郭晓艺 周兴兵 刘茂 《Agricultural Science & Technology》 CAS 2012年第9期1873-1876,1895,共5页
[Objective] The aim was to study the relationship of plant characters with bud living rate and mother stem emergence rate of ratoon rice before harvest. [Method] Eighteen mid-season hybrid rice cultivators approved re... [Objective] The aim was to study the relationship of plant characters with bud living rate and mother stem emergence rate of ratoon rice before harvest. [Method] Eighteen mid-season hybrid rice cultivators approved recently were taken as materials and relationship of plant characters including bud living rate and moth- er stem emergence rate of ratoon rice before harvest was explored, based on relat- ed data. [Result] The shorter rice with lower harvesting index is the main character of high emergence rate for first cropping rice; decline of plant height and increase of ear-bearing percentage would improve emergence of regenerative seedlings. [Conclusion] The research provided scientific reference for breeding of rice cultivars with high regenerative capacity. 展开更多
关键词 Mid-season hybrid rice Plant characters Bud living rate Emergencerate
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Performance index limits of high reinforced concrete shear wall components 被引量:1
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作者 劳晓春 韩小雷 《Journal of Central South University》 SCIE EI CAS 2011年第4期1248-1255,共8页
The deformation performance index limits of high reinforced concrete (RC) shear wall components based on Chinese codes were discussed by the nonlinear finite element method. Two typical RC shear wall specimens in th... The deformation performance index limits of high reinforced concrete (RC) shear wall components based on Chinese codes were discussed by the nonlinear finite element method. Two typical RC shear wall specimens in the previous work were first used to verify the correctness of the nonlinear finite element method. Then, the nonlinear finite element method was applied to study the deformability of a set of high RC shear wall components designed according to current Chinese codes and with shear span ratio λ≥2.0. Parametric studies were made on the influence of shear span ratio, axial compression ratio, ratio of flexural capacity to shear capacity and main flexural reinforcement ratio of confined botmdary members. Finally, the deformation performance index and its limits of high RC shear wall components under severe earthquakes were proposed by the finite element model results, which offers a reference in determining the performance status of RC shear wall components designed based on Chinese codes. 展开更多
关键词 reinforced concrete shear wall components performance index limits nonlinear finite element method Chinese codes
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A new method of characterizing equivalent strain for equal channel angular processing 被引量:1
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作者 赵军 王振华 +3 位作者 孙淑华 赵德利 任利国 傅万堂 《Journal of Central South University》 SCIE EI CAS 2009年第3期349-353,共5页
In order to establish the quantitative relationship between equivalent strain and the performance index of the deformed material within the range of certain passes for equal channel angular processing (ECAP), a new ... In order to establish the quantitative relationship between equivalent strain and the performance index of the deformed material within the range of certain passes for equal channel angular processing (ECAP), a new approach to characterize the equivalent strain was proposed. The results show that there exists better accordance between mechanical property (such as hardness or strength) and equivalent strain after rolling and ECAP in a certain range of deformation amount, and Gauss equation can be satisfied among the equivalent strain and the mechanical properties for ECAP. Through regression analysis on the data of hardness and strength after the deformation, a more generalized expression of equivalent strain for ECAP is proposed as:ε=k0exp[-(k1M-k2)^2], where M is the strength or hardness of the material, k1 is the modified coefficient (k1∈ (0, 1)), ko and k2 are two parameters dependent on the critical strain and mechanical property that reaches saturation state for the material, respectively. In this expression the equivalent strain for ECAP is characterized novelly through the mechanical parameter relating to material property rather than the classical geometry equation. 展开更多
关键词 equal channel angular processing (ECAP) equivalent strain mechanical property characterizing method
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Avian magnetic compass:Its functional properties and physical basis 被引量:2
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作者 Roswitha WILTSCHKO Wolfgang WILTSCHKO 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第3期265-276,共12页
The avian magnetic compass was analyzed in bird species of three different orders - Passeriforms, Columbiforms and Galliforms - and in three different behavioral contexts, namely migratory orientation, homing and dire... The avian magnetic compass was analyzed in bird species of three different orders - Passeriforms, Columbiforms and Galliforms - and in three different behavioral contexts, namely migratory orientation, homing and directional conditioning. The respective findings indicate similar functional properties: it is an inclination compass that works only within a functional window around the ambient magnetic field intensity; it tends to be lateralized in favor of the fight eye, and it is wavelength-dependent, requiring light from the short-wavelength range of the spectrum. The underlying physical mechanisms have been identified as radical pair processes, spin-chemical reactions in specialized photopigments. The iron-based receptors in the upper beak do not seem to be involved. The existence of the same type of magnetic compass in only very distantly related bird species suggests that it may have been present already in the common ancestors of all modem birds, where it evolved as an all-purpose compass mechanism for orientation within the home range [Current Zoology 56 (3): 265-276, 2010]. 展开更多
关键词 Magnetic compass MIGRATION HOMING Directional training Inclination compass Radical pair processes
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Hybrid particle swarm optimization with chaotic search for solving integer and mixed integer programming problems 被引量:20
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作者 谭跃 谭冠政 邓曙光 《Journal of Central South University》 SCIE EI CAS 2014年第7期2731-2742,共12页
A novel chaotic search method is proposed,and a hybrid algorithm combining particle swarm optimization(PSO) with this new method,called CLSPSO,is put forward to solve 14 integer and mixed integer programming problems.... A novel chaotic search method is proposed,and a hybrid algorithm combining particle swarm optimization(PSO) with this new method,called CLSPSO,is put forward to solve 14 integer and mixed integer programming problems.The performances of CLSPSO are compared with those of other five hybrid algorithms combining PSO with chaotic search methods.Experimental results indicate that in terms of robustness and final convergence speed,CLSPSO is better than other five algorithms in solving many of these problems.Furthermore,CLSPSO exhibits good performance in solving two high-dimensional problems,and it finds better solutions than the known ones.A performance index(PI) is introduced to fairly compare the above six algorithms,and the obtained values of(PI) in three cases demonstrate that CLSPSO is superior to all the other five algorithms under the same conditions. 展开更多
关键词 particle swarm optimization chaotic search integer programming problem mixed integer programming problem
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Application Scenarios and Enabling Technologies of 5G 被引量:13
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作者 YUAN Yifei ZHU Longming 《China Communications》 SCIE CSCD 2014年第11期69-79,共11页
Fast growth of mobile internet and internet-of-things has propelled the concept formation and research on 5G wireless communications systems which are to be standardized around 2020(IMT-2020).There will be diverse app... Fast growth of mobile internet and internet-of-things has propelled the concept formation and research on 5G wireless communications systems which are to be standardized around 2020(IMT-2020).There will be diverse application scenarios expected for 5G networks.Hence,key performance indicators(KPIs) of 5G systems would be very diverse,not just the peak data rate and average/edge spectral efficiency requirements as in previous generations.For each typical scenario,multiple technologies may be used independently or jointly to improve the transmission efficiency,to lower the cost,and to increase the number of connections,etc.Key enabling technologies are discussed which include massive MIMO,ultradense deployment specific techniques,nonorthogonal transmission,high frequency communications,etc. 展开更多
关键词 5G IMT-2020 ultra-dense networks massive MIMO non-orthogonal transmission
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Discrete element method of improved performance of railway ballast bed using elastic sleeper 被引量:8
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作者 高亮 罗奇 +2 位作者 徐旸 井国庆 蒋函珂 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期3223-3231,共9页
With the development of high-speed and heavy-haul railway in China, problems like insufficient thickness of ballast bed and overlarge track stiffness are obvious. Ballast may break into small particles and their conta... With the development of high-speed and heavy-haul railway in China, problems like insufficient thickness of ballast bed and overlarge track stiffness are obvious. Ballast may break into small particles and their contact status will deteriorate under cyclic loading, resulting in ballast degradation. Discrete element method(DEM) was used to research improved performance of ballast bed using elastic sleeper. Clusters were generated by bonding spheres to model real ballasts, while broken bonds were utilized to distinguish breakage. Two kinds of ballast beds with elastic sleeper and conventional sleeper were established, respectively. After applying cyclic loading to the models, differences of mechanical properties between two models were analyzed by contrasting their dynamic behavior indexes, such as particle contact force, sleeper settlement, vibration velocity and acceleration, breakage characteristic. The results illustrate that compared with conventional sleeper, elastic sleeper increases sleeper settlement, while reduces ballast vibration and contact force between particles, which could depress ballast breakage. 展开更多
关键词 railway ballast bed discrete element method elastic sleeper BREAKAGE mechanical property
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Detection Performance Analysis of Spectrum Sensing in Cognitive Radio Networks with Mobile Secondary Users 被引量:2
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作者 Xinyu Wang Min Jia +2 位作者 Qing Guo Xuemai Gu Jian Yang 《China Communications》 SCIE CSCD 2016年第11期214-225,共12页
The majority of existing papers about spectrum sensing have the assumption that secondary users(SUs) are stationary. However,mobility is an essential feature of mobile communications networks. In this paper,the detect... The majority of existing papers about spectrum sensing have the assumption that secondary users(SUs) are stationary. However,mobility is an essential feature of mobile communications networks. In this paper,the detection performance of spectrum sensing by mobile SUs was analyzed. Three performance metrics,i.e.,detection probability,miss detection probability and false alarm probability,were thoroughly investigated. In our analysis,a critical variable was the real-time received primary user signal power by a mobile SU. Its probability distribution and mathematical expectation were analytically derived. Moreover,the three performance metrics in single-node spectrum sensing and multi-node collaborative spectrum sensing systems were also derived. Extensive simulations were performed. The results are consistent with the theoretical analysis. And it is concluded that SU mobility has a significant impact on the detection probability and the miss detection probability,but not on the false alarm probability. 展开更多
关键词 cognitive radio spectrum sensing MOBILITY random variable analysis probability density function
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Attitude control allocation strategy of high altitude airship based on synthetic performance optimization 被引量:1
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作者 遆晓光 韩放 姚郁 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第6期746-750,共5页
This paper presents a method for solving the attitude control problem of high altitude airship (HAA) with aerodynamic fin and vectored thruster control. The algorithm is based on the synthetic optimization of dynamic ... This paper presents a method for solving the attitude control problem of high altitude airship (HAA) with aerodynamic fin and vectored thruster control. The algorithm is based on the synthetic optimization of dynamic performance and energy consumption of airship. Firstly, according to the system overall configuration, the dynamic model of HAA was established and the HAA linearized model of longitudinal plane motion was obtained. Secondly, using the classic PID control theory, the HAA attitude control system was designed. Thirdly, through analyzing the dynamic performance of airship with fin or vectored thruster control, the synthetic performance index function with different weighting functions was determined. By means of optimizing the obtained performance index function, the attitude control of high altitude airship with good dynamic performance and low energy consumption was achieved. Finally, attitude control allocation strategy was designed for the airship station keeping at an altitude of 22 km. The simulation experiment proved the validity of the proposed algorithm. 展开更多
关键词 high altitude airship attitude control synthetic performance optimization control strategy
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The Temperature Variation of a Solar Cell in Relation to Its Performance 被引量:2
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作者 M.K. EI-Adawi I.A. AI-Nuaim 《Journal of Environmental Science and Engineering》 2010年第8期56-59,共4页
The temperature of a solar cell subjected to the incident global solar radiation as a function of the local day time is determined. A heat balance equation is solved considering the heat losses due to convection and t... The temperature of a solar cell subjected to the incident global solar radiation as a function of the local day time is determined. A heat balance equation is solved considering the heat losses due to convection and thermal radiation. The cell efficiency is estimated as a measure of its performance. The results reveal that the temperature within the cell attains significant values. Nevertheless, the temperature dependence of its efficiency along the day time is not pronouncing. It slightly decreases with temperature. 展开更多
关键词 Solar cell performance diurnal solar cell temperature heat balance equation.
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Glass formation,thermal and mechanical properties of ZrCuAlNi bulk metallic glasses 被引量:1
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作者 C.E.BORJA I.A.FIGUEROA +3 位作者 O.LOZADA-FLORES M.ESTRADA G.A.LARA-RODRIGUEZ J.A.VERDUZCO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第6期1157-1165,共9页
The glass forming ability, thermal and mechanical properties of some Zr Cu Al Ni bulk metallic glasses were analyzed. The compositions of the alloys were theoretically determined with the dense packing and kinetic fra... The glass forming ability, thermal and mechanical properties of some Zr Cu Al Ni bulk metallic glasses were analyzed. The compositions of the alloys were theoretically determined with the dense packing and kinetic fragility index models. Cylindrical and conical ingots were produced by copper mould suction-casting under Ar atmosphere. The conical ingots were characterized by means of X-ray diffraction in order to determine the glassy structure. It was found that both alloys have a critical glassy diameter, Dc, of 3 mm. Thermal behaviours were investigated by differential scanning calorimetry at heating rates of 0.5, 0.67 and 0.83 K/s. The gamma parameter γ, supercooled liquid region ΔTx, and reduced glass transition temperature Trg, of the experimentally obtained glasses indicated high glass forming ability. The glassy compositions showed a fragility index of ~40 GPa. The compression test of the investigated alloys was carried out at a strain rate of 0.016 s^-1, obtaining a elastic modulus of ~83 GPa, total deformation of ~5%, yield strength of 1.6 GPa and hardness of 4 GPa. It was concluded that the use of the dense packing and kinetic fragility index models helped to predict glass-forming compositions in the family alloy investigated. 展开更多
关键词 bulk metallic glass glass formation ability fragility index packing efficiency suction casting
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