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机群系统中一种新的自适应结点分配算法:受限负载平衡结点分配(LLBA) 被引量:4
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作者 雷州 徐志伟 祝明发 《计算机学报》 EI CSCD 北大核心 1999年第8期877-881,共5页
在机群系统中结点分配策略根据一定的原则为作业确定运行结点是提高系统性能的关键.通过对机群结点分配策略的研究,作者发现当前基于负载平衡自适应结点分配策略为并行作业选择负载最轻的结点,这不利于系统性能的充分发挥.作者提出... 在机群系统中结点分配策略根据一定的原则为作业确定运行结点是提高系统性能的关键.通过对机群结点分配策略的研究,作者发现当前基于负载平衡自适应结点分配策略为并行作业选择负载最轻的结点,这不利于系统性能的充分发挥.作者提出了一种新的自适应负载平衡结点分配算法:受限负载平衡结点分配(LLBA).它的基本思想是为并行作业选取负载相近的计算结点,使得并行作业分配在各结点上的运算部分具有相同的运算速度,减少运算结点的空闲等待时间,提高系统的吞吐率.通过模拟实验,将LLBA和传统的负载平衡自适应结点分配进行比较,LLBA能够明显改善机群系统的性能. 展开更多
关键词 负载平衡 自适应分配 算法 LLBA 机群系统
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连续梁的多结点力矩分配法 被引量:2
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作者 张宇 《力学与实践》 CSCD 北大核心 2003年第5期77-80,共4页
计算了连续梁在结点力偶荷载作用下柔度矩阵的表达式,在此基础上,提出了多结点力矩分配法.对于一个承受任意荷载的N个结点的连续梁,该方法同时松开多个结点,通过迭代获得各结点转角值,然后利用杆件的转角位移方程就可获得杆端弯矩的值.... 计算了连续梁在结点力偶荷载作用下柔度矩阵的表达式,在此基础上,提出了多结点力矩分配法.对于一个承受任意荷载的N个结点的连续梁,该方法同时松开多个结点,通过迭代获得各结点转角值,然后利用杆件的转角位移方程就可获得杆端弯矩的值.该方法综合了位移法和力矩分配法的优点,较传统力矩分配法可显著减少计算工作量. 展开更多
关键词 连续梁 点力矩分配 位移法 柔度矩阵 计算方法
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Functional Equilibrium Between Photosynthetic and Above-ground Nonphotosynthetic Structures of Plants: Evidence from a Pruning Experiment with Three Subtropical Tree Species 被引量:4
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作者 曾波 《Acta Botanica Sinica》 CSCD 2003年第2期152-157,共6页
It is well known that plants have functional equilibrium between their above-ground parts (shoots) and below-ground parts (roots), but whether the above-ground parts of plants have functional equilibrium between their... It is well known that plants have functional equilibrium between their above-ground parts (shoots) and below-ground parts (roots), but whether the above-ground parts of plants have functional equilibrium between their photosynthetic structures (leaves) and non-photosynthetic structures (branches and stem) is unknown. The purpose of this study is to test the hypotheses that: (1) the above-ground parts of plants have functional equilibriums between their photosynthetic structures and non-photosynthetic structures; (2) the maintenance of the equilibriums is guaranteed by the alteration of biomass partitioning to photosynthetic and non-photosynthetic structures. To test these hypotheses, a pruning experiment with four pruning intensities (0%, 20%, 50%, and 70%) were carried out with three subtropical Chinese tree species ( Ficus microcarpa, Ficus virens, Cinnamomum camphora). Pruning treatments were conducted in two successive years. The results were in conformity with the hypothesis, i.e. above-ground parts of trees had functional equilibriums between photosynthetic and non-photosynthetic structures. Pruning decreased instantaneously the mass ratios of photosynthetic structures to non-photosynthetic structures (P/NP) of all three tree species, the reduction in P/NP was strengthened with pruning intensity. However, one year after pruning, the P/NP of all pruned trees increased and were not smaller than those of unpruned trees. In agreement with the expectation, the biomass partitioning of pruned trees was altered, more newly produced above-ground biomass was partitioned to leaf growth and less to branch and stem growth, thus enabled the damaged trees to restore their functional equilibrium between photosynthetic and non-photosynthetic structures. It is clear that the maintenance of functional equilibrium between photosynthetic and non-photosynthetic structures guaranteed by the alteration of biomass partitioning provides plants a good strategy to resist external disturbance and damage. 展开更多
关键词 biomass partitioning functional equilibrium non-photosynthetic structures photosynthetic structures tree
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海南省人民政府办公厅关于扩大灾后城镇保障性住房保障范围的指导意见
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《海南省人民政府公报》 2014年第15期16-16,共1页
琼府办[2014]110号各市、县、自治县人民政府,省政府直属各单位:今年7月18日,超强台风"威马逊"对我省部分市县城镇居民家庭住房造成严重影响,为妥善安置受灾城镇居民基本生活,切实满足中低收入住房困难家庭的基本住房需求,现... 琼府办[2014]110号各市、县、自治县人民政府,省政府直属各单位:今年7月18日,超强台风"威马逊"对我省部分市县城镇居民家庭住房造成严重影响,为妥善安置受灾城镇居民基本生活,切实满足中低收入住房困难家庭的基本住房需求,现就扩大灾后城镇保障性住房保障范围提出如下指导意见:一、结合棚户区改造,做好受灾居民受损房屋建设工作。各市县政府要将受损房屋建设列入城市棚户区改造、危旧房改造和城中村改造相关规划中统筹考虑,整合、调整改造项目。 展开更多
关键词 后城镇 棚户区改造 超强台风 城中村 城镇居民家庭 限价商品房 受灾居民 房屋建设 家庭收入 分配结
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Changes of Wage Structures in Chinese Public and Private Sectors: 1995-2007 被引量:1
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作者 Xinxin Ma 《Management Studies》 2016年第6期243-255,共13页
Using CHIP (Chinese Household Income Project Survey) data and the sample selection bias corrected wage function model, this paper estimated changes in wage structure in China by ownership types (SOEs, COEs, FEs, an... Using CHIP (Chinese Household Income Project Survey) data and the sample selection bias corrected wage function model, this paper estimated changes in wage structure in China by ownership types (SOEs, COEs, FEs, and PEs) in 1995 and 2007. The major conclusions are as follows. First, effects of education on wage levels in SOEs and FEs become greater, while education effects decrease in SOEs and PEs under economic transition periods; firm-specific human capital becomes more important in the wage determination mechanism along with market-oriented reforms in SOEs, PEs, and FEs; age effect decreases in SOEs and COEs, but it becomes greater in PEs and FEs. Second, there exist wage structure differences between sectors by wage distributions. For example, in 2007, in SOEs, education return rates are higher for the low-wage and middle-wage groups, and the effect is the highest at the 40th percentile. However in COEs and FEs, education return rates are higher for the high-wage groups, and the effect is the highest at the 70th percentile in COEs and at the 70th percentile in FEs. Tenure effects are greater in the middle-wage groups (40th-80th) in SOEs, COEs, and FEs, and age effects are greater in the low-wage groups (5th-30th) in SOEs, FEs, and PEs. 展开更多
关键词 public and private sectors wage structure human capital Chinese economic transition
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ADSORPTION ISOTHERMS AND POTENTIAL DISTRIBUTIONS OF NITROGEN ON VARIOUS ACTIVATED CARBONS 被引量:3
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作者 LI Xiang LI Zhong LUO lingai 《Chinese Journal of Reactive Polymers》 2005年第1期8-13,共6页
The adsorption isotherms of four activated carbons (Norit Rill, Chemviron BPL, Monolit, and Ambersorb-572) have been examined by nitrogen adsorption at 77.5 K. A method for adsorption potential distribution calculat... The adsorption isotherms of four activated carbons (Norit Rill, Chemviron BPL, Monolit, and Ambersorb-572) have been examined by nitrogen adsorption at 77.5 K. A method for adsorption potential distribution calculation has been proposed based on the adsorption isotherms. This distribution provides information about possible changes in the Gibbs free energy caused by the energetic and geometrical heterogeneities of an activated carbon as well as by the adsorbate-related entropic effects. The general character of the adsorption potential distribution is clearly visible by its simple relation to the micropore and mesopore distribution, 展开更多
关键词 Adsorption isotherms Adsorption potential distributions MICROPORE STRUCTURE Structural heterogeneity.
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The Least Distributive Lattice Congruence on Commutative Distributive Semiring 被引量:7
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作者 LI Shi-zheng,LI Shan-hai,YU Xiao-ming (Department of Mathematics, Shandong Normal University, Shandong 250014,China) 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第1期35-43,共9页
In this paper, we describe the least distributive lattice congruence on a commutative distributive semiring.
关键词 SEMIRING commutative distributive semiring distributive lattice congruence
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Optimizing Earth Allocation for Rock-Fill Dam Construction 被引量:1
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作者 钟登华 胡程顺 张静 《Transactions of Tianjin University》 EI CAS 2005年第2期146-151,共6页
An optimal allocation of earth is of great significance to reduce the project cost and duration in the construction of rock-fill dams. The earth allocation is a dynamic system affected by various time-space constraint... An optimal allocation of earth is of great significance to reduce the project cost and duration in the construction of rock-fill dams. The earth allocation is a dynamic system affected by various time-space constraints. Based on previous studies, a new method of optimizing this dynamic system as a static one is presented. In order to build a generalized and flexible model of the problem, some man-made constraints were investigated in building the mathematic model. Linear programming and simplex method are introduced to solve the optimization problem of earth allocation. A case study in a large-scale rock-fill dam construction project is presented to demonstrate the proposed method and its successful application shows the feasibility and effectiveness of the method. 展开更多
关键词 rock-fill dam construction earth allocation dynamic allocation linear programming
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The Empirical Analysis of the Impacts of Income Distribution Gap on Consumption Demand:Based on the Statistic Data of Chinese Urban Residents in 2000-2010
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作者 Qian Long Zhao Yong Zhong Sheng 《Chinese Journal of Population,Resources and Environment》 2012年第4期116-120,共5页
This paper analyzes the impact of income distribution gap on consumption demand from a theoretical view,and draws the conclusion that there is an inverse relationship between income distribution gap and consumption de... This paper analyzes the impact of income distribution gap on consumption demand from a theoretical view,and draws the conclusion that there is an inverse relationship between income distribution gap and consumption demand.Then,the paper finds that the existing widening income distribution gap in China has a negative impact on consumption demand,but this is not the key factor for the insufficient consumption demand because of the low level of per capital income.At last,it suggests that governments should improve the income level of entire residents and adjust income distribution structure simultaneously. 展开更多
关键词 income distribution gap consumption demand elas- ticity coefficient substitution effects
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The Novel Spectrum Allocation Algorithm in Cognitive Radio System 被引量:2
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作者 Xiangqian Che Yupeng Xie +2 位作者 Ye Tian Qijing Zhang Guizhi Sun 《China Communications》 SCIE CSCD 2017年第3期108-117,共10页
In order to reduce the disturbance on an authorizing user and lower the competition between cognitive users, assure the normal communication of a cognitive radio system, reliability theory is applied to describe if a ... In order to reduce the disturbance on an authorizing user and lower the competition between cognitive users, assure the normal communication of a cognitive radio system, reliability theory is applied to describe if a channel can be used by a cognitive user or not and the probability that the channel is continually used for a period. Three aspects including space, time domain and frequency domain are united for the research on the distribution of frequency spectrum. The simulation result shows that, in the space domain, time domain, frequency domain algorithm, the transmitted data volume and the total throughput of the system are superior to those in greedy algorithm and time domain—frequency domain algorithm, the novel algorithm is helpful to reduce the disturbance caused by a cognitive user to an authorizing user and lower the competition between cognitive users, this simulation result shows that the proposed algorithm is effective. 展开更多
关键词 reliability theory spectrum allocation cognitive radio normal communication
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Study of Competitive Chelating Reaction between Lanthanum and Tribromoarsenazo in the Medium of Weak Acid by Capillary Zone Electrophoresis
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作者 胡涌刚 周培疆 +1 位作者 邓延倬 程介克 《Journal of Donghua University(English Edition)》 EI CAS 2003年第2期83-88,共6页
Two kinds of metal chelates of rare earth elements reacted with tribrimoarsenazo formed under the condition of critic acid were observed by simultaneous technique of capillary electrophoresisphotothermal interference ... Two kinds of metal chelates of rare earth elements reacted with tribrimoarsenazo formed under the condition of critic acid were observed by simultaneous technique of capillary electrophoresisphotothermal interference spectrometry. The tendency of the conversion between these chelates as functions of the mole ratio of the reagent and the metal, pH value and the elapsing time was investigated. Kinetic equation of competitive chelating reaction between the TBA-La (Ⅲ) and La (Ⅲ) -critic acid were established. It was found that the competitive chelating reaction follows secondorder kinetics, for this second-order reaction, k=5.55 L·mol-1·S-1. 展开更多
关键词 capillary electrophoresis PHOTOTHERMAL tribrimoar- senazo competitive chelating reaction
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Dynamic selection scheme for cooperative relay under high mobility environment
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作者 赵军辉 Du Jiajiao 《High Technology Letters》 EI CAS 2014年第4期363-366,共4页
The mobility of relay has great influence on the performance of a cooperative relay system.This paper proposes a dynamic selection scheme under the amplify-and-forward communication mode in high mobility environment,b... The mobility of relay has great influence on the performance of a cooperative relay system.This paper proposes a dynamic selection scheme under the amplify-and-forward communication mode in high mobility environment,based on the estimation of channels and the power allocation for each relay node by comparing it with the pre-set threshold.This scheme is used to choose the cooperative relay dynamically for a multiple relay scenario.Simulation results show that this proposed relay selection scheme decreases the outage probability effectively,maintains system capacity well,and improves the performance of the relay system. 展开更多
关键词 high mobility cooperative relay dynamic selection
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Dynamic Time Division Multiple Access Algorithm for Industrial Wireless Hierarchical Sensor Networks
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作者 杨彦红 张晓彤 +1 位作者 罗琼 李文超 《China Communications》 SCIE CSCD 2013年第5期137-145,共9页
Industrial wireless sensor networks adopt a hierarchical structure with large numbers of sensors and routers. Time Division Multiple Access (TDMA) is regarded as an efficient method to reduce the probability of confli... Industrial wireless sensor networks adopt a hierarchical structure with large numbers of sensors and routers. Time Division Multiple Access (TDMA) is regarded as an efficient method to reduce the probability of confliction. In the intra-cluster part, the random color selection method is effective in reducing the retry times in an application. In the inter-cluster part, a quick assign algorithm and a dynamic maximum link algorithm are proposed to meet the quick networking or minimum frame size requirements. In the simulation, the dynamic maximum link algorithm produces higher reductions in the frame length than the quick assign algorithm. When the number of routers is 140, the total number of time slots is reduced by 25%. However, the first algorithm needs more control messages, and the average difference in the number of control messages is 3 410. Consequently, the dynamic maximum link algorithm is utilized for adjusting the link schedule to the minimum delay with a relatively high throughput rate, and the quick assign algorithm is utilized for speeding up the networking process. 展开更多
关键词 TDMA wireless sensor network industrial wireless sensor network
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Observation of nuclei reassembled from demembranatedXenopus sperm nuclei and analysis of their laminacomponents
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作者 QUJIAN CHUANMAOZHANG 《Cell Research》 SCIE CAS CSCD 1994年第2期163-172,共10页
A cell-free preparation obtained from extracts of activated Xenopus laevis eggs induced chromatin decondensation and nuclear formation from demembranated Xenopus sperm nuclei. Electron microscopy revealed that the rea... A cell-free preparation obtained from extracts of activated Xenopus laevis eggs induced chromatin decondensation and nuclear formation from demembranated Xenopus sperm nuclei. Electron microscopy revealed that the reassembled nucleus had a double-layered nuclear membrane, nuclear pore complexes, and decondensed chromatin etc. Indirect immunofluorescence analysis demonstrated the presence of lamina in newly assembled nuclei. Western-blotting results showed that lamin LII was present in egg extracts and in lamina of the reassembled nuclei which were previously reported to contain only eggderived lamin LIII. 展开更多
关键词 Nuclear assembly in vitro Xenopus laevis LAMINA
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Two-Stage Resource Allocation Scheme for Three-Tier Ultra-Dense Network 被引量:5
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作者 Junwei Huang Pengguang Zhou +2 位作者 Kai Luo Zhiming Yang Gongcheng He 《China Communications》 SCIE CSCD 2017年第10期118-129,共12页
In 5 G Ultra-dense Network(UDN), resource allocation is an efficient method to manage inter-small-cell interference. In this paper, a two-stage resource allocation scheme is proposed to supervise interference and reso... In 5 G Ultra-dense Network(UDN), resource allocation is an efficient method to manage inter-small-cell interference. In this paper, a two-stage resource allocation scheme is proposed to supervise interference and resource allocation while establishing a realistic scenario of three-tier heterogeneous network architecture. The scheme consists of two stages: in stage I, a two-level sub-channel allocation algorithm and a power control method based on the logarithmic function are applied to allocate resource for Macrocell and Picocells, guaranteeing the minimum system capacity by considering the power limitation and interference coordination; in stage II, an interference management approach based on K-means clustering is introduced to divide Femtocells into different clusters. Then, a prior sub-channel allocation algorithm is employed for Femtocells in diverse clusters to mitigate the interference and promote system performance. Simulation results show that the proposed scheme contributes to the enhancement of system throughput and spectrum efficiency while ensuring the system energy efficiency. 展开更多
关键词 ultra-dense network resource allocation logarithmic function K-means
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Joint routing and resource allocation in optical transport networks
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作者 SU Yang XU Zhan-qi LIU Zeng-ji 《Optoelectronics Letters》 EI 2006年第6期449-451,共3页
A layered network model for optical transport networks is proposed in this paper,which involves IP,SDH and WDM layers.The strategy of Dynamic Joint Routing and Resource Allocation (DJRRA) and its algorithm description... A layered network model for optical transport networks is proposed in this paper,which involves IP,SDH and WDM layers.The strategy of Dynamic Joint Routing and Resource Allocation (DJRRA) and its algorithm description are also presented for the proposed layered network model.DJRRA optimizes the bandwidth usage of interface links between different layers and the logic links inside all layers.The simulation results show that in contrast to the classical separate sequential routing and resource allocation solutions,DJRRA can reduce the blocking probability and increase network throughput effectively. 展开更多
关键词 点路由 资源分配 光传输网络 WDM层
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Cooperative Dynamics in Lattice-Embedded Scale-Free Networks
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作者 SHANG Li-Hui ZHANG Ming-Ji YANG Yan-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第9期411-415,共5页
We investigate cooperative behaviors of lattice-embedded scale-free networking agents in the prisoner'sdilemma game model by employing two initial strategy distribution mechanisms,which are specific distribution t... We investigate cooperative behaviors of lattice-embedded scale-free networking agents in the prisoner'sdilemma game model by employing two initial strategy distribution mechanisms,which are specific distribution to themost connected sites (hubs) and random distribution.Our study indicates that the game dynamics crucially dependson the underlying spatial network structure with different strategy distribution mechanism.The cooperators' specificdistribution contributes to an enhanced level of cooperation in the system compared with random one,and cooperationis robust to cooperators' specific distribution but fragile to defectors' specific distribution.Especially,unlike the specificcase,increasing heterogeneity of network does not always favor the emergence of cooperation under random mechanism.Furthermore,we study the geographical effects and find that the graphically constrained network structure tends toimprove the evolution of cooperation in random case and in specific one for a large temptation to defect. 展开更多
关键词 geographical networks prisoner's dilemma COOPERATION HETEROGENEITY
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Crystal Structure and Molecular Structure of Binuclear Copper(Ⅱ) Complex, [Cu (C_5H_5NO) (C_6H_5COO)_2]_2
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作者 杨瑞娜 谌了容 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1995年第2期122-126,共5页
At room temperature, dibenzoyl peroxide and pyridine N-oxide reacted with metallic copper powder in a mixed solvent(dichloromethane, trichloromethane and tetrahydrofuran), resulting in a binuclear copper(Ⅱ) complex. ... At room temperature, dibenzoyl peroxide and pyridine N-oxide reacted with metallic copper powder in a mixed solvent(dichloromethane, trichloromethane and tetrahydrofuran), resulting in a binuclear copper(Ⅱ) complex. [Cu (C_5H_5NO)-(C_6H_5COO)_2]_2. The structure of the complex was characterized by elemental analyses.IR spectra and X-ray single crystal analysis. The crystal is triclinic, space group P1,with cell parameters . a= 9. 262(4) ,b= 10. 697(2) , c=10. 881 (3 )A , a=59. 60( 2 ),β= 74. 83 ( 3 ) .Y = 72. 80 ( 2 )°. V= 880. 0 A ̄3 . D_c = 1 . 5 20 g/cm ̄3 . Z = 1 . μ= 1 2. 7 cm-1, R=0. 044 ,R_w=0. 048 for 3477 reflections with I>3σ(I), M_r=805. 78. Each copper(Ⅱ) atom is coordinated by four bridging bidentate benzoate ligands and one pyridine M-oxide. 展开更多
关键词 crystal structure binuclear copper complex oxidation addition
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Actual implementation of spectrum-sharing systems in rayleigh fading channels~
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作者 裴二荣 Wang Sheng Zhang Zhizhong 《High Technology Letters》 EI CAS 2012年第2期145-150,共6页
In actual implementation of spectrum sharing systems, due to the selfishness of primary users, primary users often refuse the access of secondary users to their licensed spectrum bands even if the access of secondary ... In actual implementation of spectrum sharing systems, due to the selfishness of primary users, primary users often refuse the access of secondary users to their licensed spectrum bands even if the access of secondary users doesn't affect their transmission. Aimed at the selfishness problem of primary users, a seller's market trading mechanism is introduced which can not only stimulate primary users to tolerate larger interference power but also give the primary users an appropriate compensation at the same time, and which has very important practical significance. Based on the mechanism, the achievable maximal gross profit of secondary users and their optimal power allocation scheme in the Rayleigh fading environment are derived, and the interference price of primary users and the average revenue of secondary users' impact on them are also studied. Numerical calculation results are conducted to verify our theoretical results. 展开更多
关键词 cognitive radio spectrum sharing power allocation seller's market trading mechanism CONVEXOPTIMIZATION
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Cage and ladder structures of silsesquioxanes characterized by UV-MALDI-TOF mass spectrometry 被引量:1
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作者 尤宏 胡立江 +2 位作者 刘琰 张兴文 张皓 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第3期295-299,共5页
The molar mass distribution of SSO in the first generation derived from the hydrolytic condensation oftwo trialkoxysilanes, [ 3- ( Methacryloxy ) propyl ] trimethoxysilane ( MPMS ) and vinyltrimethoxysilane ( VMS ) ,a... The molar mass distribution of SSO in the first generation derived from the hydrolytic condensation oftwo trialkoxysilanes, [ 3- ( Methacryloxy ) propyl ] trimethoxysilane ( MPMS ) and vinyltrimethoxysilane ( VMS ) ,are determined by UV-MALDI-TOF MS. The comparisons of theoretical masses with experimental masses arecalculated using the proposed compounds, which are assigned to formulas Tn (OH)m, Tn (OMe)y orTn(OH)x(OMe)y[T=RSiO1.5 (x+y)/2n, R=--(CH2)3OOCCH(CH3)CH2 and--CHCH2]. Both theproposed cage and ladder structures of SSO derived from similar sol-gel process of monomers are illustrated. Thecauses for the difference in structures between SSO M and SSO V is discussed as well. 展开更多
关键词 molar mass distribution hydrolytic condensation cage and ladder structure
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