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991.
992.
Huan Huang 《Information Sciences》2010,180(19):3806-3813
This paper shows that the Zadeh’s extensions of sendograph-metric-continuous fuzzy-valued functions are sendograph-metric-continuous fuzzy functions. 相似文献
993.
994.
陈涛 《数字社区&智能家居》2011,(7X):5237-5240
随着以上海石化和上海化学工业区为主体的上海石油化工生产基地及相关产业的发展,与其配套的综合服务业已成为产业区结构与功能提升的重要内容。结合国内外相关案例及区域整体发展状况,探讨并分析了上海石油化工生产基地综合配套服务业的发展模式。对服务性产业发展状况、产业发展战略、规划选址、服务功能等进行了相关研究。 相似文献
995.
996.
以Cortex—M3处理器LM3S811为核心,设计了面向森林生态监测的物联网数据采集终端分站系统。通过单总线数字式温湿度传感器、烟雾传感器、CO2传感器和环境光亮度传感器分别采集温度、湿度、可燃性颗粒物、CO2含量和光照等与林木生态相关的环境信息和林场防火的相关信息。由LM3S81l处理器处理并添加分站ID和校验码后... 相似文献
997.
Jun Wang Bormin Huang Jiaji Wu Jong‐Wha Chong 《Journal of the Society for Information Display》2011,19(8):551-560
Abstract— Overdrive is commonly used to reduce the liquid‐crystal response time and motion blur in liquid‐crystal displays (LCDs). However, overdrive requires a large frame memory in order to store the previous frame for reference. In this paper, a lapped transform‐based codec (LTC) is proposed to reduce the frame memory needed for LCD overdrive. In the latest literature, a directional prediction‐based codec (DPC) employs eight directional predictions, which takes up a large percentage of the computational complexity of the codec and does not consider the de‐correlation of the inter‐blocks. Therefore, the LTC first uses the lapped transform to decompose the correlation of the inter‐blocks in the YUV color space. A hadamard transform is then used for energy compaction. The reordered coefficients are pre‐quantized and encoded using the proposed adaptive bit‐plane coding (ABPC) method for a simple hardware implementation. The simulation results show that the proposed LTC significantly improves the DPC in both subjective and objective performance and outperforms the block truncation coding (BTC) and adaptive multi‐level BTC (AM‐BTC), which have been described in the literature. 相似文献
998.
It is difficult to find the optimal sparse solution of a manifold learning based dimensionality reduction algorithm. The lasso
or the elastic net penalized manifold learning based dimensionality reduction is not directly a lasso penalized least square
problem and thus the least angle regression (LARS) (Efron et al., Ann Stat 32(2):407–499, 2004), one of the most popular algorithms
in sparse learning, cannot be applied. Therefore, most current approaches take indirect ways or have strict settings, which
can be inconvenient for applications. In this paper, we proposed the manifold elastic net or MEN for short. MEN incorporates
the merits of both the manifold learning based dimensionality reduction and the sparse learning based dimensionality reduction.
By using a series of equivalent transformations, we show MEN is equivalent to the lasso penalized least square problem and
thus LARS is adopted to obtain the optimal sparse solution of MEN. In particular, MEN has the following advantages for subsequent
classification: (1) the local geometry of samples is well preserved for low dimensional data representation, (2) both the
margin maximization and the classification error minimization are considered for sparse projection calculation, (3) the projection
matrix of MEN improves the parsimony in computation, (4) the elastic net penalty reduces the over-fitting problem, and (5)
the projection matrix of MEN can be interpreted psychologically and physiologically. Experimental evidence on face recognition
over various popular datasets suggests that MEN is superior to top level dimensionality reduction algorithms. 相似文献
999.
Fei Wang Tao Li Xin Wang Shenghuo Zhu Chris Ding 《Data mining and knowledge discovery》2011,22(3):493-521
Complex networks exist in a wide range of real world systems, such as social networks, technological networks, and biological
networks. During the last decades, many researchers have concentrated on exploring some common things contained in those large
networks include the small-world property, power-law degree distributions, and network connectivity. In this paper, we will
investigate another important issue, community discovery, in network analysis. We choose Nonnegative Matrix Factorization
(NMF) as our tool to find the communities because of its powerful interpretability and close relationship between clustering
methods. Targeting different types of networks (undirected, directed and compound), we propose three NMF techniques (Symmetric
NMF, Asymmetric NMF and Joint NMF). The correctness and convergence properties of those algorithms are also studied. Finally
the experiments on real world networks are presented to show the effectiveness of the proposed methods. 相似文献
1000.
This paper presents an automatic stock portfolio selection system. In the proposed approach, 53 financial indices are collected
for each stock item and are consolidated into six financial ratios [Grey relational grades (GRGs)] using a Grey relational
analysis model. The GRGs are processed using a modified form of the PBMF index method (designated as the Huang index function)
to determine the optimal number of clusters per GRG. The resulting cluster indices are then processed using rough set theory
to identify the stocks within the lower approximate sets. Finally, the GRGs of each stock item in the lower approximate sets
are consolidated into a single GRG, indicating the ability of the stock item to maximize the rate of return. It is demonstrated
that the proposed stock selection mechanism yields a higher rate of return than several existing portfolio selection systems. 相似文献