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1.
根据路和星、圈的多重Mycielski图的结构性质,用穷染递推的方法,讨论了图Mn(Cm)和Mn(Pm),以及Mn(Sm)的邻点可区别I-全染色,得到了图Mn(Sm)和Mn(Pm)的邻点可区别I-全色数等于它们的最大度,图Mn(Cm)的邻点可区别I-全色数在m=4,5时等于它的最大度加1,其余情况等于它的最大度,即分别给出图Mn(Sm)和Mn(Cm)、Mn(Pm)一种染色方案。  相似文献   

2.
为了有效解决具有不确定性和多极小性的随机优化问题 ,提出了一类基于假设检验的遗传算法 .该方法通过多次评价来进行解性能的合理估计 ,利用遗传操作来进行解空间的有效搜索 ,采用假设检验来增加种群的多样性和算法的探索能力 ,从而避免遗传算法的早熟收敛 .基于典型的随机函数优化和组合优化问题 ,仿真研究了假设检验、性能估计次数、噪声幅度对算法性能的影响 ,验证了所提方法的有效性和鲁棒性  相似文献   

3.
为研究基于HU差别矩阵属性约简的核(HCore(C))、信息熵属性约简的核(ECore(C))、分布属性约简的核(FCore (C))、最大分布属性约简的核( MCore (C))、近似属性约简的核(ACore (C))和正区域属性约简的核(PCore (C))之间的关系,本文给出了上述各种核的简化差别矩阵计算方法,并用上述各种核的计算方法证明了如下结论:在不一致决策表中,HCore( C)(∩)ECore( C):FCore( C) (∩)ACore( C)) (∩)PCore( C);用实例说明了MCore(C))和ACore(C))之间没有关系,MCore (C))和PCore (C))之间没有关系;而在一致决策表中,各种不同核是相互等价的.  相似文献   

4.
5.
Receptor-binding affinities for the alpha(1) adrenoceptor subtypes alpha(1a), alpha(1b) and alpha(1d) for a series of 39 alpha(1) adrenoceptor antagonists derived from the antipsychotic sertindole are reported. The SAR of the compounds with respect to affinity for the alpha(1a), alpha(1b) and alpha(1d) adrenoceptor subtypes as well as affinity obtained by an alpha(1) assay (rat brain membranes) were investigated using a 3D-QSAR approach based on the GRID/GOLPE methodology. Good statistics (r(2)=0.91-0.96; q(2)=0.65-0.73) were obtained with the combination of the water (OH2) and methyl (C3) probes. The combination of steric repulsion and electrostatic attractions explain the affinities of the included molecules. The adrenergic alpha(1a) receptor seems to be more tolerant to large substituents in the area between the indole 5- and 6-positions compared to the adrenergic alpha(1b) and alpha(1d) receptor subtypes. There seems to be minor differences in the position of areas in the alpha(1b) receptor compared to alpha(1a) and alpha(1d) receptors where electrostatic interaction between the molecules and the receptor (OH2 probe) contribute to increased affinity. These observations may be used in the design of new subtype selective compounds. In addition, the model based on biological data from an alpha(1) assay (rat brain membranes) resembles the model for the alpha(1b) adrenoceptor subtype.  相似文献   

6.
神经网络用于三元分子混合物密度与粘度的预测   总被引:5,自引:3,他引:2  
以二元系实验为基础,利用反向转播算法训练神经网络,构造混合物组成,温度等与物性关系的模型,用于对4个三元混合物体系(1)邻二甲苯-间二甲苯-对二甲苯;(2)四氯化碳-环己烷-2-丙醇;(3)甲醇-丙酮-水;(4)水-甲醇-乙二醇的密度和5个三元混合物体系(1)信甲苯-间二甲苯-对二甲苯;(2)四氯化碳-环己烷-2-丙醇;(3)氯仿-2-丙醇-2-丁醇;(4)甲醇-丙酮-水;(5)乙醇-甲醇-水的粘  相似文献   

7.
拓扑指数X用于脂肪醇的QSPR研究   总被引:1,自引:0,他引:1  
为了更好地揭示脂肪醇的各种物理化学性质与结构的关系,通过对100余种饱和脂肪醇分子的拓扑结构特点的研究,提出1种新的拓扑指数X,并运用回归分析方法研究了饱和脂肪醇的沸点(BP)、空腔表面积(CSA)、折光指数(n_D)、光离子化灵敏度(SM),半数致死浓度(LC_(50)),疏水性参数(lgP)和味阀值(poL)等多种物理化学性质与拓扑指数X的相关性,建立了定量结构-性质相关(QSPR)模型。结果表明所建立的QSPR模型方程具有良好的稳定性和预测能力,较好地揭示了这些物理化学性质的变化规律。  相似文献   

8.
The effects of polymer species (poly(vinylidene fluoride)) (PVdF) homopolymer or poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF(HFP) copolymer), average molecular weight of the polymer, and the HFP content in PVdF(HFP) on the electrochemical and electromechanical properties of actuators using polymer-supported single-walled carbon nanotube (SWCNT)–ionic liquid (IL) gel electrodes were investigated. For the PVdF (Kynar 741 or 761) actuator containing 1-ethyl-3-methylimidazolium tetrafluoroborate (EMI[BF4]), the generated strain was 0.90–1.05% for the frequency range of 0.01–0.005 Hz, which was over twice as large as that for the PVdF(HFP) (Kynar Flex 2801) actuator. Furthermore, it is considered that the HFP content should be low (or zero) for large generated strain and zero for large maximum stress. The PVdF actuator performs much better than the PVdF(HFP) actuator and has a quick response, sufficient for practical application (e.g., tactile displays).  相似文献   

9.
In this paper, a novel cooperative path planning scheme of unmanned surface vehicles (USVs) for rescuing targets in a complex ocean environment is proposed. The primary objective of the rescue USVs is to bring all targets back safely on the premise of first rescuing priority targets, while optimizing the path length, the navigation time and the angular energy. The main contributions of this paper are as follows: (1) The proposed K-means-division (KMD) algorithm is able to identify a complex ocean environment with collision-free zone and static-obstacles zone; (2) The proposed path planning method with fast-marching-method-based ellipse guidance range (E-FMM) is able to optimize the angular energy while ensuring safety; (3) The proposed cooperative management system (including priority-target-assignment (PTA) with reward-mechanism genetic-optimization (RM-GO) and collision-avoidance (CA) guidance law with Tangent-based surge-varying wave-disturbances-observer (Tangent-SV-WDO)) can accomplish the mission of the rescue USVs. Comparative studies with the state-of-the-art methods demonstrate that the proposed cooperative path planning scheme is superior in terms of priority-target-assignment (PTA) and collision-avoidance (CA) of the actual rescue work.  相似文献   

10.
Predictive Maintenance is a type of condition-based maintenance that assesses the equipment's states and estimates its failure probability and when maintenance should be performed. Although machine learning techniques have been frequently implemented in this area, the existing studies disregard to the natural order between the target attribute values of the historical sensor data. Thus, these methods cause losing the inherent order of the data that positively affects the prediction performances. To deal with this problem, a novel approach, named Ordinal Multi-dimensional Classification (OMDC), is proposed for estimating the conditions of a hydraulic system's four components by taking into the natural order of class values. To demonstrate the prediction ability of the proposed approach, eleven different multi-dimensional classification algorithms (traditional Binary Relevance (BR), Classifier Chain (CC), Bayesian Classifier Chain (BCC), Monte Carlo Classifier Chain (MCC), Probabilistic Classifier Chain (PCC), Classifier Dependency Network (CDN), Classifier Trellis (CT), Classifier Dependency Trellis (CDT), Label Powerset (LP), Pruned Sets (PS), and Random k-Labelsets (RAKEL)) were implemented using the Ordinal Class Classifier (OCC) algorithm. Besides, seven different classification algorithms (Multilayer Perceptron (MLP), Support Vector Machine (SVM), k-Nearest Neighbour (kNN), Decision Tree (C4.5), Bagging, Random Forest (RF), and Adaptive Boosting (AdaBoost)) were chosen as base learners for the OCC algorithm. The experimental results present that the proposed OMDC approach using binary relevance multi-dimensional classification methods predicts the conditions of a hydraulic system's multiple components with high accuracy. Also, it is clearly seen from the results that the OMDC models that utilize ensemble-based classification algorithms give more reliable prediction performances with an average Hamming score of 0.853 than the others that use traditional algorithms as base learners.  相似文献   

11.
12.
In this paper we describe a mean value analysis algorithm to solve product form queueing network models of the Baskett, Chandy, Muntz, and Palacios type (BCMP) [5]. These networks can accommodate multiple job classes and load dependent service stations. The networks can be closed (i.e., jobs neither enter nor leave the network), open (i.e., jobs can enter and leave the network), or mixed (i.e., closed with respect to some job classes and open with respect to others). Two major aspects of this paper are:
1. (1)to present a unified approach to the solution of this class of BCMP queueing networks [5], and
2. (2)to thereby extend and consolidate the results of the work of several authors (Balbo, Bruell and Schwetman (1977), Bruell and Balbo (1980), Chandy and Sauer (1980), Krzesinki, Teunissen and Kritzinger (1981), Resier and Kobayashi (1975), Reiser and Lavenberg (1980), Reiser (1981), Sauer (1983), Schwetman (1980), Tucci and MacNair (1982) and Zahorjan and Wong (1981)).

The paper concludes by collecting together all the results into an explicit algorithm, MVALDMX (for mean value analysis load dependent mixed) that is a generalization of the original MVA algorithm of Reiser and Lavenberg (1978, 1980).  相似文献   


13.
A set of mobile devices that employs wireless transmission for communication is termed Mobile Ad hoc Networks (MANETs). Offering better communication services among the users in a centralized organization is the primary objective of the MANET. Due to the features of MANET, this can directly End-to-End Delay (EED) the Quality of Service (QoS). Hence, the implementation of resource management becomes an essential issue in MANETs. This paper focuses on the efficient Resource Allocation (RA) for many types of Traffic Flows (TF) in MANET. In Mobile Ad hoc Networks environments, the main objective of Resource Allocation (RA) is to process consistently available resources among terminals required to address the service requirements of the users. These three categories improve performance metrics by varying transmission rates and simulation time. For solving that problem, the proposed work is divided into Queue Management (QM), Admission Control (AC) and RA. For effective QM, this paper develops a QM model for elastic (EL) and inelastic (IEL) Traffic Flows. This research paper presents an AC mechanism for multiple TF for effective AC. This work presents a Resource Allocation Using Tokens (RAUT) for various priority TF for effective RA. Here, nodes have three cycles which are: Non-Critical Section (NCS), Entry Section (ES) and Critical Section (CS). When a node requires any resources, it sends Resource Request Message (RRM) to the ES. Elastic and inelastic TF priority is determined using Fuzzy Logic (FL). The token holder selects the node from the inelastic queue with high priority for allocating the resources. Using Network Simulator-2 (NS-2), simulations demonstrate that the proposed design increases Packet Delivery Ratio (PDR), decrease Packet Loss Ratio (PLR), minimise the Fairness and reduce the EED.  相似文献   

14.
The organic field effect transistors (OFETs) with regioregular poly 3-hexylthiophene (rr-P3HT) and hexafluoro-2-propanol-substituted polysiloxane (SXFA) as an organic layer, have been used for detection of explosive vapors with excellent sensitivity of less than 70 ppt for 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) and less than 100 ppt for 2,4,6-trinitrotoluene (TNT). The sensor response (% change in saturation current) was found to be 125 ± 10% for TNT and 90 ± 10% for RDX. It was also observed that the incorporation of CuII tetraphenylporphyrin (CuTPP) into rr-P3HT/SXFA matrix resulted in an improved selectivity for the vapors of nitro based analytes (TNT, RDX and DNB) as compared to the vapors of non explosive oxidizing agents such as nitrobenzene (NB), benzoquinone (BQ) and benzophenone (BP). This is attributed to the increased binding of the vapors containing nitro compound to the thin films due to the presence of CuTTP. Spin coated thin films were further characterized by Atomic Force Microscopy (AFM) and Electrostatic Force Microscopy (EFM).  相似文献   

15.
进化计算简要综述   总被引:19,自引:1,他引:18  
介绍进化计算的起源与发展历史、进化计算的特点与分类、进化计算有关研究与应用现状、进化计算有关软件与国际信息交流等方面的基本情况。  相似文献   

16.
NUSH is a block cipher as a candidate for NESSIE. NUSH is analyzed by linear crypt-analysis . The complexity δ = (ε , η) of the attack consists of data complexity ε and time complexity η. Three linear approximations are used to analyze NUSH with 64-bit block. When |K| = 128 bits, the complexities of three attacks are (258, 2124), (260, 278) and (262, 255) respectively. When |K| = 192 bits, the complexities of three attacks are (258, 2157) (260, 2%) and (262, 258) respectively. When |K| = 256 bits, the complexities of three attacks are (258, 2125), (260, 278) and (262, 253) respectively. Three linear approximations are used to analyze NUSH with 128-bit block. When |K|= 128 bits, the complexities of three attacks are (2122, 295), (2124, 257) and (2126, 252) respectively. When |K| = 192 bits, the complexities of three attacks are (2122, 2142), (2124, 275) and (2126, 258) respectively. When |K|= 256 bits, the complexities of three attacks are (2122, 2168), (2124, 281) and (2126, 264) respectively. Two l  相似文献   

17.
A comparison of the performance of three feature extraction methods was made for mapping forest crown closure (CC) and leaf area index (LAI) with EO-1 Hyperion data. The methods are band selection (SB), principal component analysis (PCA) and wavelet transform (WT). Hyperion data were acquired on October 9, 2001. A total of 38 field measurements of CC and LAI were collected on August 10-11, 2001, at Blodgett Forest Research Station, University of California at Berkeley, USA. The analysis method consists of (1) conducting atmospheric correction with High Accuracy Atmospheric Correction for Hyperspectral Data (HATCH) to retrieve surface reflectance, (2) extracting features with the three methods: SB, PCA and WT, (3) establishing multivariate regression prediction models, (4) predicting and mapping pixel-based CC and LAI values, and (5) validating the CC and LAI mapped results with photo-interpreted CC and LAI values. The experimental results indicate that the energy features extracted by the WT method are the most effective for mapping forest CC and LAI (mapped accuracy (MA) for CC=84.90%, LAI MA=75.39%), followed by the PCA method (CC MA=77.42%, LAI MA=52.36%). The SB method performed the worst (CC MA=57.77%, LAI MA=50.87%).  相似文献   

18.
根据MOPAC2009软件包中PM6算法得到的分子描述符研究半透膜仪(SPMDs)采集大气中多氯联苯(PCBs)采样速度(R_(air))的定量构效关系(QSPR)模型,并分析影响R_(air)的关键因素。以半经验PM6算法得到的分子量子化学描述符作为预测变量,采用偏最小二乘算法(PLS)构建了R_(air)的QSPR模型。根据交叉验证,所得到的最佳模型中PLS成分解释的因变量的累积变异(Q~2_(cum))为0.683,这表明该模型具有良好的预测能力和稳健性。通过外部验证和将实验测得的R_(air)与预测得到的R_(air)进行比较,对所构建模型的稳定性和可靠性进行了验证,结果表明无论是训练组还是预测组,其预测值与实测值间均具有较好的线性关系,线性相关系数均大于0.8376。对PCBs采样速度R_(air)的主要影响因素为PCBs与SPMDs中甘油三油酸酯分子间的相互作用大小和为将PCBs溶解在甘油三油酸酯中形成洞穴所需能量要求。  相似文献   

19.
裴东林  李旭 《计算机应用》2013,33(11):3244-3246
针对RSA算法中Z*φ(n)的代数结构问题,提出了一种在强素数条件下应用二次剩余理论进行研究的方法。给出了Z*φ(n)中元素阶的计算公式和元素的最大阶表达式,计算了Z*φ(n)中二次剩余的个数和二次非剩余的个数,同时估计出Z*φ(n)中元素的最大阶上限为φ(φ(n))/4并得到了Z*φ(n)中元素的最大阶达到φ(φ(n))/4的一个充要条件。另外还给出了全部二次剩余构成的子群A1成为循环子群的充分条件及Z*φ(n)的一种分解方法。最后证明了Z*φ(n)可由7个二次非剩余元素生成,商群Z*φ(n)/A1是一个Klein八元群。  相似文献   

20.
通过分析条件接收(Conditional Access System,CAS)基本原理以及关键技术,研究数字电视标准中授权控制信息发生器(ECMG)、授权管理信息发生器(EMMG)、同密同步器(SCS)和复用器(MUX)之间的通信协议等,提出一种ECMG、EMMG、SCS与MUX通信的软件解决方案,用于产生授权管理信息(ECM)和授权控制信息(EMM),实现服务器与加扰机之间多线程通信。  相似文献   

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