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水盐体系组分数计算公式的一个条件
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作者 苑庆忠 马德茹 《山东轻工业学院学报(自然科学版)》 CAS 1997年第1期65-67,共3页
给出了水盐体系组分数计算公式(c=m+n)的一个证明。
关键词 水盐体系 组分数计算 证明
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考试分数分布的研究
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作者 于信凤 《现代教育管理》 北大核心 1989年第5期97-100,共4页
考试的分数分布是分析考生状况、据以改进教学工作的重要依据,是评价考试工作、据以改进考试设计的重要基础。那么,考试分数的什么样的分布才是正常的?正态分布是各类考试的理想的分数分布吗?为研究这个问题我们首先说明一下分数分布及... 考试的分数分布是分析考生状况、据以改进教学工作的重要依据,是评价考试工作、据以改进考试设计的重要基础。那么,考试分数的什么样的分布才是正常的?正态分布是各类考试的理想的分数分布吗?为研究这个问题我们首先说明一下分数分布及其特征的描述,分析一下决定和影响考试分数分布的因素。 展开更多
关键词 分布 考试工作 选拔考试 教学工作 资格考试 负偏态 相对优劣 组分数 峰态 既定标准
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“分数大小的比较”愉快教学设计
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作者 张光荣 《四川教育》 北大核心 1995年第1期40-41,共2页
【愉快教学片断一】创设情景,导入新课师: 今天老师给大家讲一个“猪八戒吃西瓜”的故事. 唐僧师徒四人到西天取经. 有一天, 天气十分炎热,
关键词 愉快教学 大小 生产计划 猪八戒 直观感知 西瓜 组分数 操作实践 单位 引导学生
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“分数的基本性质”教学计划
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作者 陈秀花 《青海教育》 北大核心 1996年第4期45-45,共1页
“分数的基本性质”教学计划陈秀花教学内容:六年制小学数学第十册“分数的基本性质”。教学要求:使学生理解分数的基本性质,并会把一个分数化成指定分母(或分子)做分母(或分子),而大小不变的分数。教学重、难点:导出分数的基... “分数的基本性质”教学计划陈秀花教学内容:六年制小学数学第十册“分数的基本性质”。教学要求:使学生理解分数的基本性质,并会把一个分数化成指定分母(或分子)做分母(或分子),而大小不变的分数。教学重、难点:导出分数的基本性质,应用分数的基本性质。单元划... 展开更多
关键词 基本性质 教学计划 教学要求 组分数 自学提纲 大小相同 “都” 学第十册 作业设计 导出分
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基于非负CP分解模型的边界规避任务中脑电特征提取方法研究 被引量:1
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作者 付荣荣 于宝 孙洁娣 《中国生物医学工程学报》 CAS CSCD 北大核心 2021年第1期53-59,共7页
通过建立"碗-球"模型,执行有视觉引导的边界规避任务,以提高受试者的脑电唤醒度。在与"碗-球"模型交互过程中,采集10名健康被试关于左、右手两类运动任务的脑电数据,通过对脑电的优化特征进行分类,以实现对运动意... 通过建立"碗-球"模型,执行有视觉引导的边界规避任务,以提高受试者的脑电唤醒度。在与"碗-球"模型交互过程中,采集10名健康被试关于左、右手两类运动任务的脑电数据,通过对脑电的优化特征进行分类,以实现对运动意图的解码。基于边界规避任务诱发的脑电信号进行8~13 Hz带通滤波,获得特定频带的数据,通过连续小波变换获取脑电的频率分量,生成脑电张量。采用非负CP分解模型提取脑电张量的时间组分特征,再用二维主成分分析优化特征,利用支持向量机(SVM)实现特征分类,并与采用共空间模式(CSP)和SVM的特征提取及特征分类方法进行比较。所有被试的结果显示:CP分解的通用最佳组分数为16,基于非负CP分解模型特征提取方法,利用SVM分类的准确率为95.5%±3.0%,AUC值为0.978 2±0.012 1,分类结果优于CSP+SVM的分类准确率(93.7%±3.1%),通过t检验来检验分类结果的判别分数,分类结果具有95%的置信度(P<0.05)。基于非负CP分解模型提取特征进行运动意图分类,能够反映出边界规避任务中不同状态的差异,提高分类的性能。 展开更多
关键词 边界规避 脑电 非负CP分解 最佳组分数
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三年级柜台
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作者 周洁 《数学小灵通(烧脑版)(中高年级)》 2006年第6期33-36,10,共5页
北师大版课标实验教材小朋友们,在学习了有关“面积”和“分数”的知识后,你们能应用这些知识解决问题吗?快来试试吧!
关键词 占地面积 总面积 组分数 三年级 学知识 规律 信息 柜台 香港特别行政区 长度单位
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相律的正确表达及其在特殊点的应用
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作者 赵凤云 林志宏 《吉林工学院学报(自然科学版)》 1994年第3期60-63,共4页
本文从相律推导出发,考察了如何正确表达相律。建议删除组分数C的概念,并且用相律解释了临界点的零自由度问题。
关键词 相律 临界点 组分数 零自由度 平衡体系 表达式
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DISTRIBUTED SIMULATION SYSTEM BASED ON UNIVERSAL COMPONENTS
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作者 孙知信 王汝传 王绍棣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第1期69-75,共7页
Based on MATRIXx, a universal real-time visual distributed simulation system is developed. The system can receive different input data from network or local terminal. Application models in the simulation modules can a... Based on MATRIXx, a universal real-time visual distributed simulation system is developed. The system can receive different input data from network or local terminal. Application models in the simulation modules can automatically get such data to be analyzed and calculated, and then produce real-time simulation control information. Meanwhile, this paper designs relevant simulation components to implement the input and output data, which can guarantee the real-time and universal of the data transmission. Result of the experimental system shows that the real-time performance of the simulation is perfect. 展开更多
关键词 distributed simulation data collection universal component
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An Equation of Stirling Numbers of the Second Kind 被引量:3
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作者 DU Chun-yu ZHANG Jian-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第2期261-263,共3页
In this paper, We propose and prove the following equation, where {3^n} is a stirling number of the second kind, when n ≥ 3 is given.
关键词 COMBINATIONS stirling numbers of the second kind
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A New System of Variational Inclusions with (H,η)-accretive Operators in Banach Spaces 被引量:3
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作者 LIU Ying CHEN Yong-li HE Zhen 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期565-573,共9页
In this paper, we first introduce a new class of generalized accretive operators named (H,η)-accretive in Banach space. By studying the properties of (H,η)-accretive, we extend the concept of resolvent operators... In this paper, we first introduce a new class of generalized accretive operators named (H,η)-accretive in Banach space. By studying the properties of (H,η)-accretive, we extend the concept of resolvent operators associated with m-accretive operators to the new (H,η)-accretive operators. In terms of the new resolvent operator technique, we prove the existence and uniqueness of solutions for this new system of variational inclusions. We also construct a new algorithm for approximating the solution of this system and discuss the convergence of the sequence of iterates generated by the algorithm. 展开更多
关键词 q-uniformly smooth Banach space (H η)-accretive operator resolvent operator technique system of variational inclusion iterative algorithm
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Delay-Differentiated Scheduling in Optical Packet Switches for Cloud Data Centers 被引量:2
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作者 LI Yaofang XIAO Jie +5 位作者 WU Bin WEN Hong YU Hongfang YANG Shu XIN Shanshan GUO Jianing 《China Communications》 SCIE CSCD 2015年第8期22-32,共11页
We consider differentiated timecritical task scheduling in a N×N input queued optical packet s w itch to ens ure 100% throughput and meet different delay requirements among various modules of data center. Existin... We consider differentiated timecritical task scheduling in a N×N input queued optical packet s w itch to ens ure 100% throughput and meet different delay requirements among various modules of data center. Existing schemes either consider slot-by-slot scheduling with queue depth serving as the delay metric or assume that each input-output connection has the same delay bound in the batch scheduling mode. The former scheme neglects the effect of reconfiguration overhead, which may result in crippled system performance, while the latter cannot satisfy users' differentiated Quality of Service(Qo S) requirements. To make up these deficiencies, we propose a new batch scheduling scheme to meet the various portto-port delay requirements in a best-effort manner. Moreover, a speedup is considered to compensate for both the reconfiguration overhead and the unavoidable slots wastage in the switch fabric. With traffic matrix and delay constraint matrix given, this paper proposes two heuristic algorithms Stringent Delay First(SDF) and m-order SDF(m-SDF) to realize the 100% packet switching, while maximizing the delay constraints satisfaction ratio. The performance of our scheme is verified by extensive numerical simulations. 展开更多
关键词 delay-differentiated packetscheduling optical switch data center cloudservice
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Energy Efficiency Based on Joint Data Packet Fragmentation and Cooperative Transmission 被引量:3
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作者 ZHANG Zufan YI Yinxue YANG Jing JING Xiaorong 《China Communications》 SCIE CSCD 2014年第10期96-105,共10页
Energy efficiency(EE) is a key requirement for the design of short-range communication network.In order to alleviate energy consumption(EC) constraint,a novel layered heterogeneous mobile cloud architecture is propose... Energy efficiency(EE) is a key requirement for the design of short-range communication network.In order to alleviate energy consumption(EC) constraint,a novel layered heterogeneous mobile cloud architecture is proposed in this paper.Based on the proposed layered heterogeneous mobile cloud architecture,we establish an appropriate energy consumption model,and design an energy efficiency scheme based on joint data packet fragmentation and cooperative transmission and analyze the energy efficiency corresponding to different packet sizes and the cloud size.Simulation results show that,when all nodes of the cloud are accessing the same size of data packet fragmentation,the proposed layered heterogeneous mobile cloud architecture can provide significant energy savings.The results provide useful insights into the possible operation of the strategies and show that significant energy consumption reductions are possible. 展开更多
关键词 layered heterogeneous mobilecloud energy efficiency data packetfragmentation cooperative transmission
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Fractal Uniform Circular Arrays Based Multi-Orbital-Angular-Momentum-Mode Multiplexing Vortex Radio MIMO 被引量:3
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作者 Linjun Zhao Hailin Zhang Wenchi Cheng 《China Communications》 SCIE CSCD 2018年第9期118-135,共18页
A radio wave driven by Orbital angular momentum(OAM) is called a vortex radio and has a helical wavefront. The differential helical wavefronts of several vortex radios are closely related to their topological charges ... A radio wave driven by Orbital angular momentum(OAM) is called a vortex radio and has a helical wavefront. The differential helical wavefronts of several vortex radios are closely related to their topological charges or mode numbers. In physics, two or more radio waves with different mode numbers are orthogonal to their azimuth angles. With the development of radio communication technologies, some researchers have been exploring the OAM-based multi-mode multiplexing(multi-OAM-mode multiplexing) technologies in order to enhance the channel spectrum efficiency(SE) of a radio communication system by using the orthogonal properties of vortex radios. After reviewing the reported researches of OAM-based radio communication, we find that some breakthroughs have been made in the combination of OAM and traditional Multi-Input-Multi-Output(MIMO). However, the existing technology is not sufficient to support OAM-based MIMO system to achieve maximum the channel SE. To maximize the spectrum efficiency of OAM-based MIMO system, we present a reused multi-OAM-mode multiplexing vortex radio(RMMVR) MIMO system, which is based on fractal uniform cir-cular arrays(UCAs). The scheme described in this study can effectively combine multiOAM-mode multiplexing with MIMO spatial multiplexing. First, we present the generation of RMMVR MIMO signals. Second, under line-of-sight(LOS) propagation conditions, we derive the channels of the RMMVR MIMO system. Third, we separate the RMMVR MIMO signals using an orthogonal separation method based on full azimuth sampling. Finally, we introduce the method for calculating the channel capacity of the RMMVR MIMO system. Theoretical analysis shows that the scheme proposed in this study is feasible. Moreover, the simulation results show that spatial and mode diversity are obtained by exploiting fractal UCAs. However, to enhance the channel SE of RMMVR MIMO system, an interference cancellation method needs to be introduced for zero-mode vortex radios, and some methods of multi-OAM-mode beams convergence and mode power optimization strategy should be introduced in the future. 展开更多
关键词 vortex radio reused multi-OAM-mode multiplexed vortex radio (RMMVR) MIMO fractal uniform circular arrays(UCAs) signal orthogonal separation.
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POSET: A High-Performance Application Layer Multicast Protocol Design and Implementation 被引量:1
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作者 T. Ruso C. Chellappan 《China Communications》 SCIE CSCD 2014年第12期83-93,共11页
Many research issues have been raised in Application Layer Multicasting(ALM),such as group management,security,integrity of data,link stress,link stretch,load balancing,fault tolerance and scalability,because of the s... Many research issues have been raised in Application Layer Multicasting(ALM),such as group management,security,integrity of data,link stress,link stretch,load balancing,fault tolerance and scalability,because of the shifting of the multicast protocol from the IP layer to the application layer.To address these issues many protocols have evolved by changing their topology structure.In this paper,the POSET protocol stack is proposed,which consists of three layers,such as communication control,POSET cube,and content distribution.The novelty of this paper is the lattice-based data distribution with POSET cube architecture.The results have been compared with the existing NICE and Narada protocols.The experimental results show that the proposed POSET protocol improves throughput between 7.14%and 40%and decreases the delay between 7.69%and 25%,compared to the existing NICE protocol. 展开更多
关键词 multicast link stress link stretch POSET cube
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Molecular Simulations of FCC Dry Gas Components Adsorption in Zeolite Y 被引量:1
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作者 Ding Xue Liu Yibin +2 位作者 Yang Chaohe Shan Honghong Chen Fangwen 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2016年第1期100-107,共8页
Adsorption of FCC dry gas components, hydrogen(H_2), nitrogen(N_2), methane(CH_4), ethane(C_2H_6) and ethylene(C_2H_4) in zeolite Y was studied by performing the Grant Canonical Monte Carlo(GCMC) simulations at 298K a... Adsorption of FCC dry gas components, hydrogen(H_2), nitrogen(N_2), methane(CH_4), ethane(C_2H_6) and ethylene(C_2H_4) in zeolite Y was studied by performing the Grant Canonical Monte Carlo(GCMC) simulations at 298K and 823K and under a pressure range up to 10 MPa. Simulation results were analyzed using the Langmuir model, which presented fitting of dry gas components adsorption to be suggested as the monolayer adsorption. C_2H_4 presented most single adsorption amount, which reached 7.63 mol/kg at 298K under a pressure of 200kPa. Thermodynamic parameters of the Gibbs free energy change, enthalpy change and entropy change were analyzed based on adsorption equilibrium constant obtained from the GCMC simulations. The results suggested that it was more favorable for C_2H_4 to be adsorbed in zeolite Y. Adsorption molecules were in ordered arrangement in the zeolite, and C_2H_4 exhibited a more orderly arrangement than other components. Additionally, a competition in the adsorption of a mixture of dry gas components was found, and supercages were the priority adsorption space. The competition was favorable to CH_4 and C_2H_6, and the competitive power was affected by temperature. 展开更多
关键词 adsorption dry gas zeolite molecular simulation Monte Carlo method
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Explosion limits for combustible gases 被引量:10
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作者 TONG Min-ming WU Guo-qing HAO Ji-fei DAI Xin-lian 《Mining Science and Technology》 EI CAS 2009年第2期182-184,共3页
Combustible gases in coal mines are composed of methane, hydrogen, some multi-carbon alkane gases and other gases. Based on a numerical calculation, the explosion limits of combustible gases were studied, showing that... Combustible gases in coal mines are composed of methane, hydrogen, some multi-carbon alkane gases and other gases. Based on a numerical calculation, the explosion limits of combustible gases were studied, showing that these limits are related to the concentrations of different components in the mixture. With an increase of C4H10 and C6H14, the Lower ExplosionLimit (LEL) and Upper Explosion-Limit (UEL) of a combustible gas mixture will decrease clearly. For every 0.1% increase in C4H10 and C6H14, the LEL decreases by about 0.19% and the UEL by about 0.3%. The results also prove that, by increasing the amount of H2, the UEL of a combustible gas mixture will increase considerably. If the level of HE increases by 0.1%, the UEL will increase by about 0.3%. However, H2 has only a small effect on the LEL of the combustible gas mixture. Our study provides a theoretical foundation for judging the explosion risk of an explosive gas mixture in mines. 展开更多
关键词 coal mine GAS explosive gases explosion limits
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Stability of Linear Integrodifferential Systems with Time-varied Confficients with Large Scale
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作者 蒋里强 马知恩 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第4期41-45, ,共5页
In this paper, we concertrate our efforts on discuss asymptotic stability of linear inte grodifferential systems with time-varied confficients with large scale via Liapunov functional and decomposite - aggregated meth... In this paper, we concertrate our efforts on discuss asymptotic stability of linear inte grodifferential systems with time-varied confficients with large scale via Liapunov functional and decomposite - aggregated method. A group of sufficient conditions are given to guarantee asymptotic stability of zero solutions of systems. 展开更多
关键词 integrodifferential systems Liapunov functionals decomposite-aggregated method asymptotic stability
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On a Generalization of Some Restrictive Distribution Theorems
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作者 田震 张松 《Chinese Quarterly Journal of Mathematics》 CSCD 1995年第3期78-85,共8页
This paper is on a distribution question of Ⅰ type in the combinatorics (see: 'Ke Zhao, Wei WanDi, combinatorial theory, science press, 1981. '). Suppose n distrinct balls, m distinct boxes. The capacity set... This paper is on a distribution question of Ⅰ type in the combinatorics (see: 'Ke Zhao, Wei WanDi, combinatorial theory, science press, 1981. '). Suppose n distrinct balls, m distinct boxes. The capacity set of every box is Now,place the n balls into the m boxes. Thenumber of distinct placed ways is expressed by , and simply by And it is called the distribution number.Main result is:Theorem The exponential generating function of sequence isThus .there is the recurrence relationhere (integer set). 展开更多
关键词 the distribution of Ⅰtype exponential generating function COMBINATORICS
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Membership Proof and Verification in Authenticated Skip Lists Based on Heap 被引量:1
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作者 Shuanghe Peng Zhige Chen Deen Chen 《China Communications》 SCIE CSCD 2016年第6期195-204,共10页
How to keep cloud data intact and available to users is a problem to be solved. Authenticated skip list is an important data structure used in cloud data integrity verification. How to get the membership proof of the ... How to keep cloud data intact and available to users is a problem to be solved. Authenticated skip list is an important data structure used in cloud data integrity verification. How to get the membership proof of the element in authenticated skip list efficiently is an important part of authentication. Kaouthar Blibech and Alban Gabillon proposed a head proof and a tail proof algorithms for the membership proof of elements in the authenticated skip list. However, the proposed algorithms are uncorrelated each other and need plateau function. We propose a new algorithm for computing the membership proof for elements in the authenticated skip list by using two stacks, one is for storing traversal chain of leaf node, the other is for storing authentication path for the leaf. The proposed algorithm is simple and effective without needing plateau function. It can also be applicable for other similar binary hash trees. 展开更多
关键词 authenticated skip list max heap membership proof STACK algorithms
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Flow Label-Based TPv6 Packet Classification Algorithm with Dimension Reduction Capability
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作者 黄小红 马严 《China Communications》 SCIE CSCD 2012年第5期1-9,共9页
Traditional packet classification for IPv4 involves examining standard 5-tuple of a packet header, source address, destination address, source port, destination port and protocol. With introduction of IPv6 flow label ... Traditional packet classification for IPv4 involves examining standard 5-tuple of a packet header, source address, destination address, source port, destination port and protocol. With introduction of IPv6 flow label field which entails labeling the packets belonging to the same flow, packet classification can be resolved based on 3 dimensions: flow label, source address and desti- nation address. In this paper, we propose a novel approach for the 3-tuple packet classification based on flow label. Besides, by introducing a conversion engine to covert the source-destination pairs to the compound address prefixes, we put forward an algorithm called Reducing Dimension (RD) with dimension reduction capability, which combines heuristic tree search with usage of buck- ets. And we also provide an improved version of RD, called Improved RD (IRD), which uses two mechanisms: path compression and priority tag, to optimize the perforrmnce. To evaluate our algo- rithm, extensive experiraents have been conducted using a number of synthetically generated databas- es. For the memory consumption, the two pro- posed new algorithms only consumes around 3% of the existing algorithms when the number of ill- ters increases to 10 k. And for the average search time, the search time of the two proposed algo- rithms is more than four times faster than others when the number of filters is 10 k. The results show that the proposed algorithm works well and outperforms rmny typical existing algorithms with the dimension reduction capability. 展开更多
关键词 IPV6 packet classification flow label
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